Author: lcoffice

Concerns of the chemist that I am

This title is a tribute to the famous French biologist and humanist, Jean Rostand. In 1967 he published Inquiétudes d’un biologiste (Concerns of a biologist). It is sometimes well for a blatant error to draw attention to overmodest truths!

As long as 55 years ago, significant residues of DDT were found in Adélie penguins and crab-eater seals of the Antarctic [Sladen et al. 1966]. This very clearly demonstrates that DDT, as well as many other pesticides, must be highly resistant. Their residues are found several thousand kilometres away from the application areas. Many chemical contaminants are long distance travellers!

Although obviously not new, the observation highlights that assessing the exposure routes of environmental chemical contaminants that threaten health is a priority challenge for the 21st century. Because they are so widespread, we are all exposed to a huge mix of products, many of which actually worsen the effect of others. They interact and disrupt our metabolisms, even if the individual molecules have no effect. In addition, they can interact through different mechanisms. This we refer to as “cocktail effects” [Svingen & Vinggaard 2016].

There is no escaping the very pertinent question that haunts so many people. Do these chemicals threaten our health? An original study by the French Agency for Food, Environmental and Occupational Health & Safety identified the main diets and the corresponding cocktails of some twenty contaminants [Traoré et al. 2016 & 2018]. The classes of contaminants are heavy metals, mycotoxins, polycyclic aromatic hydrocarbons, pesticides and others. In a follow-up study, researchers assessed the effects of individual molecules and the effects of characteristic mixtures. Obviously, the cocktail effect exceeds the sum of the individual effects. The conclusion is not surprising: the contaminants exhibit synergistic effects [Kopp. et al. 2018].

Are these contaminants pathogens? Is the body able to repel their attacks? Is the body failing to remove the contaminants? Many experts alert us to the relationship between the omnipresence of chemicals and the marked increase in so-called societal diseases such as obesity, diabetes, infertility, behavioural and cognitive disorders, and food allergies. The increased risk of morbidity derives from contaminants in our food and consumer products. Pesticides, several brominated and fluorinated organic compounds or plasticisers and bisphenols are the most dangerous. It is true that it was first thought that to cause damage these products had to persist in the body. We see however that even if the body rapidly excretes them, they have lasting effects. The effect of an exposure can reverberate many years later and even be passed on to the next generation(s). This is known as the “hit-and-run” impact [Trasande 2019].

Our future looks bleak! Many of these chemicals are harmful and are even nastier in association with other contaminants in the mixture or in the cocktail.

Human activity has introduced thousands of tons of chemicals into the environment even though we know only too well that humans absorb contaminants and store them into their blood. How can we remedy this global catastrophe, what can we do to defuse the time bomb that has been inserted into our bodies without our consent? There is no simple answer. To remove persistent pollutants, micro and nano plastics, and several other cocktails  will be anything but easy. Cleansing will take a very long time!

It would therefore be a wise move to make sure our food is safe. It is the governments that must bear the final responsibility for the quality control of products on the market, for the necessary chemical and microbiological tests, and for risk assessment. All of this requires appropriate techniques. Limiting ourselves to determining concentrations in order to compare them with toxicological reference values is of little use. This approach is based on the evaluation of substances taken individually and does not provide any information about the reaction they cause in the presence of a complex cocktail. Nevertheless, emerging techniques, such as bio-analytical methods, multi-residue analyses and in silico techniques, offer promising prospects. Combining them with molecule-by-molecule analyses will allow us to identify the harmful effects of the cocktail as well as the most dangerous contaminants. For a secure future, it will be necessary to tackle the cocktail of contaminants with a cocktail of techniques [Goeyens 2020]. It is generally accepted that governments and industry should apply a class-based approach to chemicals rather than the molecule-by-molecule approach in order to develop safer alternatives and methods and eliminate many environmental contaminants [Blum 2016; Kwiatkowski et al. 2020].

Needless to say, the consumer also has a role to play. Let us steer clear of ultra-processed foods − they are often too sweet, too salty, too fatty − and increase our consumption of whole grains, fruits and vegetables, nuts and legumes. This can only improve our quality of life and help us survive diseases and pandemics like COVID-19. The virus that infects a person who is already suffering from pre-existing co-morbidities caused by the consumption of poor-quality food causes very serious problems [Pussemier & Goeyens 2020]. The presence of certain co-morbidities may indeed represent a potential risk factor, which can lead to serious clinical results.

The food we eat are often suppliers of invisible contaminants. Ensuring food security is essential for overcoming this crisis. Looking the other way would be a grave mistake! Toxins affect the body, but much worse than that, they affect the brain [Gaylord et al. 2020]. Could we really be heading towards an overall decline in human intelligence?

Mankind has opened Pandora’s jar and released all the (chemical) plagues contained therein. Only one thing was left behind as Hope − slower to react − remained locked up. So all hope is not lost since chemistry is both a curse AND a blessing.

This article is part of a more comprehensive publication in French [Goeyens 2021].

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Blum [2016]. Tackling toxics, Science 351, 6278, 1117

Gaylord et al. [2020]. Trends in neurodevelopmental disability burden due to early life chemical exposure in the USA from 2001 to 2016: A population-based disease burden and cost analysis, Molecular and Cellular Endocrinology 502, 110666

Goeyens [2020]. Keeping Cocktail Effects Under Control is the Number One Challenge for the 21st Century, EC Nutrition 15, 2, pp. 3

Goeyens [2021]. À défaut de donner un sens à l’Anthropocène, sachons en tirer des leçons, in Susanne & Vanaise (eds.) L’aventure humaine, MeMograMes, les éditions de la MéMoire, 301 – 320

Kopp. et al. [2018]. Genotoxicity and mutagenicity assessment of food contaminant mixtures present in the French diet, Environmental and Molecular Mutagenesis 59, 8, 742 – 754

Kwiatkowski et al. [2020]. Scientific Basis for Managing PFAS as a Chemical Class, Environmental Science & Technology Letters,, pp. 12

Pussemier & Goeyens [2020]. Gezonde eetwaren voor een hoogwaardige voeding, CIACO Imprimerie, pp. 236

Sladen et al. [1966]. DDT residues in Adelie penguins and a crabeater seal from Antarctica, Nature 210, 5037, 670 – 673

Svingen & Vinggaard [2016]. The risk of chemical cocktail effects and how to deal with the issue, Journal of Epidemiology and Community Health 70, 4, 322 – 323

Traoré et al. [2016]. To which chemical mixtures is the French population exposed? Mixture identification from the second French Total Diet Study, Food and Chemical Toxicology 98, 179 – 188

Traoré et al. [2018]. To which mixtures are French pregnant women mainly exposed? A combination of the second French total diet study with the EDEN and ELFE cohort studies, Food and Chemical Toxicology 111, 310 – 328

Trasande [2019]. Sicker, Fatter, Poorer: The Urgent Threat of Hormone-Disrupting Chemicals to Our Health and Future – and What We Can Do About It, Houghton Mifflin Harcourt, pp. 221

Trees should not be viewed as individuals, but as communities bound up in a complex set of ecological relationships

A tree’s most important means of staying connected to other trees is a “wood wide web” of soil fungi that connects vegetation in an intimate network that allows the sharing of an enormous amount of information and goods.

A few years ago, I bought a book by Peter Wohlleben, put it aside and forgot about it. Now it is on my desk and I have become really passionate about The Hidden Life of Trees, originally published in German and translated into dozens of languages including Dutch [Wohlleben 2015]. The author shares his passion for woods and forests and explains the striking processes of life, death, and regeneration he has observed in the woodland and the amazing scientific processes behind these exceptional events.


Found on Facebook

Much like human families, tree parents live together with their children, communicate with them, and support them as they grow, sharing nutrients with those who are sick or struggling and creating an ecosystem that mitigates the impact of extremes for the whole group [Gagliano et al. 2012]. As a result of such interactions, trees in a family or community are protected and can live to be very old. On the other hand, solitary trees, like street kids, have a tough time and often die much earlier than those in a community.
The author raises a number of questions, yet the answers to those questions are all but simple, they encourage reflection. Here is an example of the questions Wohlleben addresses.

How does the water get into the forest?

Gravity causes the water to flow to the lowest point. We all know that land and vegetation rise above sea level and that water flows to the sea. So, why don´t the continents dry up? This does not happen because clouds form over the sea and are carried by the wind. However, this mechanism only works well up to 600 kilometres from the coast. Further inland the climate becomes drier, because the clouds have emptied and disappeared. Without any additional force, life would only be possible in a narrow strip on the outside of the continents; the interior would be desolate and barren.

Fortunately, we have forests, which by the way we had better stop clearing and felling, because they are the vegetation form with the largest leaf surface. Some 27 square meters of foliage and needles form for every square meter of forest. Part of the precipitation remains on top of the trees and quickly evaporates again. Additionally, forests consume 2500 cubic meters of water per square kilometre during summer, which they release into the air through their respiration. The huge amounts of exhaled water vapour form new clouds that move inland and provide raindrops further on. This goes on and on and even the most remote places are still supplied with (some) moisture.

Forests are exceptionally efficient water pumps and constitute a mechanism that does not require any energy at all. They ensure that raindrops can travel for free over very long distances. The only condition is that there must be forests from the seaside to the most remote regions. This reminds me of Edward O. Wilson. In order to stave off the mass extinction of our planet (both vegetal and animal life) we must move swiftly to preserve the Planet´s biodiversity. In his visionary blueprint for saving the planet (Stephen Greenblatt in the preface) Wilson [2016] argues for half the surface of the Earth to nature.

Congratulations to the Russian scientists for the discovery of these important processes

Anastassia Makarieva and her colleague conducted research in different forests all over the world and invariably arrived at the same conclusions. Whether they studied the rainforest or the Siberian taiga, it was always the trees that passed on the vital moisture. This research team also concluded that the whole system collapses when coastal forests are cut down. In Brazil, the consequences are already there for all to see: the Amazon rainforest is becoming increasingly dry. Central Europe is still within the 600-kilometre zone and therefore within the suction range of the water pump. And we are very lucky that there are still forests there. They are however becoming sparser and replacement of the natural forest cover by a low leaf index vegetation is leading to significant reductions of the mean continental precipitation and runoff, in contrast to the previously available estimates made without accounting for the biotic moisture pump [Makarieva & Gorshkov 2007]. I can only repeat once more what I have said a number of times before: to replace depleted forests takes much more than simply planting trees!

Moreover, the conifers of the northern hemisphere have something else they can use to influence the climate and water balances. They emit terpenes, substances that were originally used to ward off diseases and parasites. If these molecules come into the air, moisture condenses on them. As a result, clouds are formed that are twice as dense as those over unforested surfaces. The chance of rain increases and about 5 % of the sunlight is reflected. Hence, the local climate becomes cooler and conifers simply love cooler conditions.

Can trees LOVE their local climate?

The Hidden Life of Trees infuriated professional forestry scientists while it was hailed by lay readers, who seem better able than forestry professionals to intuitively grasp the need for an ecological approach to forest management.

The reason for this divided response is that the strenght of Wohlleben´s argument heavily depends on eliciting an emotional response from readers through its powers of suggestion. As the author concludes, if we understand the capabilities of plant life and learn to recognize the trees’ emotional lives and needs, then we will also begin to treat plants differently, will cease to view forests as lumber factories, and will understand how forests can serve as oases of respite and recovery for us. His argument is intended to make us appreciate the benefits to us all as well as to the trees of leaving the forests undisturbed.

Our approach should change now. And if you do not believe me then maybe you will believe the famous French sociologist and philosopher, Edgar Morin, and what he says about industrial developments devastating not only the biosphere itself, but also humanity. If we do not change our ways, we will be plunging into the abyss [Morin 2007].

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Gagliano et al. [2012]. Towards understanding plant bioacoustics, Trends in plant science 17, 6, 323 – 325
Makarieva & Gorshkov [2007]. Biotic pump of atmospheric moisture as driver of the hydrological cycle on land, Hydrology and Earth System Sciences 11, 1013 – 1033
Morin [2007]. Vers l´abîme?, Éditions de l´Herne, pp. 181
Wilson [2016]. Half-earth – Our Planet´s Fight for Life, Liveright Publishing Corporation, pp. 259
Wohlleben [2015]. Das geheime Leben der Baüme, Ludwig Verlag, pp. 223

Forest restoration and wildlife conservation, easier said than done

At first I thought I was fighting to save rubber trees. Then I thought I was fighting to save the Amazon rainforest. Now I realise I am fighting for humanity (Chico Mendes) 

Although essential to the balance of the global ecosystem, forests are under severe strainSlash and burn fires destroy large sections of forests. But, as we are all aware, forests play a crucial role in the environment. They yield natural resources, provide valuable and even indispensable habitat for biodiversity, and they also influence the climate by storing carbon dioxide (CO2)Some believe raising new forests is an effective weapon to fight climate change and desertification [Peng et al. 2020]. The Intergovernmental Panel on Climate Change (IPCC) suggests that boosting the total area of the world’s forests, woodlands and woody savannahs could store around one-quarter of the atmospheric carbon (C) necessary to limit global warming to 1.5 C above preindustrial levels [IPCC 2018; Lewis et al. 2019]. 

For several years now, initiatives to help forests regain the land they have lost have multiplied all over the world: 350 million trees in Ethiopia, more than 66 million in India, 440 million to be planted in Ireland by 2040, one billion in Australia by 2050, etc. Madrid is planning a huge forest belt around the city. The Flemish Environment Minister, Zuhal Demir, recently decided to create 4000 hectares of new forest by 2024. She expects investments by the population. If only healthy natural forests  and not plantations  could enhance the Flemish landscape within three years! 

Afforestation can be very helpful provided projects are properly designed and closely monitored. Several recent studies have looked at the impact of planting new forests. They reveal that ill-prepared initiatives can have counterproductive effects on biodiversity as well as on the fight against climate change [Férard 2020]. Forests require urgent, continuing and long-term care if they are to produce lasting environmental benefits. 

Carefully enforced safeguards on the conversion of natural ecosystems could improve both the carbon and biodiversity outcomes of reforestation policies 

Initiatives such as the Bonn Challenge and the Trillion Trees Vision address the intertwined challenges of rural poverty, climate change and biodiversity loss through large-scale afforestation and reforestation [Heilmayer et al. 2020]. The Bonn Challenge [www.bonnchallenge.orgis a global effort to restore 150 million hectares of the world’s degraded and deforested lands by 2020. Trillion Trees [www.trilliontrees.orgis a joint venture of Birdlife International, Wildlife Conservation Society and World Wide Fund for Nature, founded on a vision of a world where tree cover is expanding not shrinking. 

Past policies and current commitments however indicate that governments mostly prioritise the planting of commercially valuable species over the restoration of natural forests. Although passive regeneration of natural forests may be an inexpensive and technically simple approach, government reforestation incentives have often favoured forests that produce wood for industrial uses [Rudel 2009]. For example, much of the growth has occurred in Asia where plantations that produce wood for local consumption remain highly important. 

The Chilean subsidy policy, for example, led to the conversion of natural forest plots into plantations. In their study, Heilmayer et al. [2020] assessed the impact of afforestation subsidies and calculated the effects on C rates and biodiversity across the country. They took into account the extent of Chilean forests according to three scenarios  the scenario currently observed, a second scenario without subsidies and a third one with subsidies coupled with a better application of restrictions  and concluded that subsidies increased the area covered by trees but reduced the area occupied by natural forests, compared to the scenario without subsidies. As natural forests are better C sinks and richer in species than plantations, the policy failed to increase C storage. Moreover, it did not slow down the biodiversity loss. Chile’s forest subsidies probably decreased biodiversity without increasing total C stored in aboveground biomass, a missed opportunity to stop the dramatic climate change. 

The success of the climate change mitigation goals depends on both the area of trees planted and the potential for carbon sequestration of each afforestation 

This was the message of an earlier IPCC [2014] report. Previous estimates of the carbon balance typically used a fixed ratio between biomass and soil C to estimate soil organic carbon (SOC) stocks [Pan et al. 2011]. This method led to large uncertainties in estimating C cycles. Moreover, scientific and political interests in regional aspects of the global carbon cycle triggered a strong impetus to better understand the C balance [Piao et al. 2009]. 

In order to predict the full-scale changes in the C cycle driven by afforestation Hong et al. [2020] looked more specifically at the impact of afforestation on soil C capture. Between 2012 and 2013, they collected thousands of soil samples from more than 600 pairs of reforested plots and control plots across northern China where the government has conducted extensive afforestation campaigns. 

They found that planting trees did indeed appear to have increased SOC density when it previously showed low concentrations. In contrast, rich soils seemed to have lost density with the planting of new plantations (for local wood utilisation). The authors suggest that their impact on C capture could be overestimated. This finding is of great importance to developers of afforestation projects. It clearly indicates that natural forest regeneration should be preferred to the planting of new trees where sites already feature non-negligible levels of  C in the soil. 

In general, afforestation leads to more evapotranspiration, which leads to decreased near-surface temperature 

Manmade as well as natural changes in land cover have a dual impact on climate. On the one hand, there are biogeochemical exchanges such as carbon dioxide emissions and storage, and on the other, there are biogeophysical effects due to changes in albedo, soil properties, and roughness. The biogeophysical effects include changes in radiation, evapotranspiration, and surface heat fluxes [Brovkin et al. 2013; Strandberg & Kjellström 2019]. The albedo effect generates colder temperatures as a consequence of deforestation, but this cooling effect is much smaller than the warming effect from greenhouse gas emissions. Moreover, biogeophysical parameters mainly have local effects. Hence, the response in climate can vary significantly between regions [Alexandru et al. 2016]. 

It is sometimes suggested that afforestation and reforestation measures could be taken into account in order not to reduce our quota of emissions. However, the outcome of these initiatives cannot be called an unqualified success. Earlier studies conducted with global (in other words, not on a regional or local scale) models at a coarse spatial resolution suggest that the albedo effect is the dominating biogeophysical effect leading to a colder climate when deforestation occurs in the Northern Hemisphere [Pongratz et al. 2009]. Currently, afforestation is considered as a mitigation strategy by CO2 sequestration, even though the reduced radiative forcing from reduced CO2 in the atmosphere might locally be counteracted by biogeophysical positive forcing [Mykleby et al. 2017; Strandberg & Kjellström 2019]. 

According to Strandberg & Kjellström [2019] the local effects on climate from maximum afforestation and deforestation are comparable in magnitude. Complete afforestation of all unforested areas in Europe leads to a general cooling of 0.5 – 3 C in all seasons. And complete deforestation of all forested areas leads to a general warming in summer of 0.5–2.5 C. 


Photo Mali Maeder 

I hardly know people who like climate warming. I hardly know people who enjoy biodiversity loss. So, we must turn the tide. But afforestation should not be a short-term fad. On the contrary, it should be a carefully considered project. Only then could it be seen to curb climate change and biodiversity loss. 

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Alexandru & Sushama [2016]. Impact of land-use and land-cover changes on CRCM5 climate projections over North America for the twenty-first century, Climate dynamics 47, 3-4, 1197 – 1209 

Brovkin et al. [2013]. Effect of Anthropogenic Land-Use and Land-Cover Changes on Climate and Land Carbon Storage in CMIP5 Projections for the Twenty-First Century, Journal of Climate 26, 6859 – 6881 

Férard [2020]. Pourquoi planter des arbres à grande échelle pourrait être contre-productif pour l’environnement, GEO 

Heilmayer et al. [2020]. Impacts of Chilean forest subsidies on forest cover, carbon and biodiversity, Nature Sustainability 

Hong et al. [2020]. Divergent responses of soil organic carbon to afforestation, Nature Sustainability 

IPCC [2014]. Climate Change 2014: Synthesis Report, pp. 151 

IPCC [2018]. Warming of 1.5°C, pp. 34 

Lewis et al. [2019]. Regenerate natural forests to store carbon, Nature 568, 25 – 28Peng et al. [2020]. The ongoing cut-down of the Amazon rainforest threatens the climate and requires global tree planting projects: A short review, Environmental Research 181, 108887 

Mykleby et al. [2017]. Quantifying the trade-off between carbon sequestration and albedo in midlatitude and high-latitude North American forests, Geophysical Research Letters 44, 2493 – 2501 

Pan et al. [2011]. A large and persistent carbon sink in the world’s forests, Science 333, 988 – 993 

Piao et al. [2009]. The carbon balance of terrestrial ecosystems in China, Nature 458, 7241, 1009  1013 

Pongratz et al. [2009]. Radiative forcing from anthropogenic land cover change since A.D. 800, Geophysical Research Letters 36, 2, pp. 5 

Rudel [2009]. Tree farms: Driving forces and regional patterns in the global expansion of forest plantations, Land Use Policy 26, 545 – 550 

Strandberg & Kjellström [2019]. Climate Impacts from Afforestation and Deforestation in Europe, Earth Interactions 23, 1, pp. 27 

Plastic rain, we can no longer avoid it

Eleven billion metric tons of plastic are projected to accumulate in the environment by 2025. Because plastics are persistent, they fragment into pieces that are susceptible to wind entrainment [Brahney et al. 2020].

The presence of plastic in the environment can no longer be denied. It has become a very frightening and global problem. Plastics have outgrown most man-made materials. The world produced ~348 million metric tons of plastic in 2017, and this number is growing every year by ~5 % [Geyer et al. 2017]. However, robust global information about their processing and end-of-life fate, is lacking. A large proportion of the production accumulates as waste in the environment. Need I remind you of the huge problem created by discarded cigarette ends and soft drink bottles. Moreover, progressive fragmentation leads to the presence of secondary plastics in terrestrial, freshwater, atmospheric, and marine environments. Extremely high resilience and longevity give plastics their quality and utility, but these same characteristics lead to the unrestrained accumulation of synthetic materials in nearly every ecosystem on the planet [Rochman 2018]. Micro and nano plastics are found where they are least expected. Here I refer to a few recent observations.

Microscopic fragments of plastic have invaded the farthest reaches of the sea, from the depths of the Mariana Trench to the freezing waters off Antarctica. Now, researchers have found that such microplastics have polluted the Pyrenees mountains, expanding plastic’s dominion to previously unknown heights. [Fox 2019].

Seemingly everywhere researchers have looked, they’ve found microplastics. They’re floating in ostensibly unspoiled air over the Pyrenees Mountains and swirling in sediments taken from the remote Barents Sea, where bottom-living creatures also have been found with microplastics in their bellies. Scientists even found microplastics in Arctic snow this summer. They’re also in our food supply: Avid mussel eaters could be consuming up to 11,000 microplastics a year, one study found. Tea lovers should be wary, too. A study published in late September found brewing methods caused a single plastic teabag to release about 11.6 billion microplastic and 3.1 billion nano plastic particles into the water [Pipkin 2020].

Chemical contaminants have spread to every corner of the earth. And this we have known for a long time! As long as 55 years ago significant DDT residues were found in Adelie penguins and crabeater seals from Antarctica [Sladen et al. 1966]. DDT as well as many other pesticides must be very resistant as they are found at several thousand kilometres from the areas where they were used. And there is also the hole in the ozone layer. Since the mid-1980s it has been known that chlorofluorocarbons as well as halocarbons (compounds where carbon atoms are linked to fluorine, chlorine, bromine, or iodine, but also to hydrogen) are mainly responsible for the destruction of the ozone layer in the stratosphere [Dameris 2010]. Chemicals that were synthesised and utilised on earth can easily travel to the stratosphere, the layer of the earth’s atmosphere that lies between 10 and 50 kilometres above the earth.

Chemical contaminants are long-distance travellers, as are micro and nano plastics. Allen et al. [2019] analysed samples, taken over five months, at the Bernadouze meteorological station in the Pyrenees mountains and identified fibres up to ~750 µm long and microplastic fragments ≤300 µm. The researchers predominantly found plastics from single-use packaging. Moreover, from their samples, they determined that each day, an average of ~365 plastic particles sifted down from above into the square meter surface of the collection device. If comparable quantities of airborne microplastic fall across the rest of the country, these researchers estimate that roughly 2000 tons (or 2 million kilograms) of plastic blanket France each year. And their computer simulations corroborated the notion that the plastic fragments, films, and fibres collected could have originated in cities, suggesting the microplastics floated at least hundreds of kilometres before falling back to Earth.

And the situation is no more encouraging on the other side of the Atlantic. Looking at samples from 11 remote areas in the western United States, including the Grand Canyon and Joshua Tree National Park, Brahney et al. [2020] noticed brightly coloured fragments under the microscope. In fact, they were looking at plastic. They found a great deal of tiny fibres, probably from clothes, carpets, and other textiles. Additionally, they found tiny particles, about 30 % of which were brightly coloured spheres, smaller than the plastic microbeads that are used in cosmetics and other personal care products. These spheres are components of paints that might be released to the atmosphere during spray painting, a whole new source that so far has not been looked into.

The American research team estimated that ~132 pieces of microplastic land on every square meter of wilderness each day. This adds up to more than 1000 tons of plastic per year across national parks and other protected areas of the western United States, the equivalent of 300 million plastic water bottles. Furthermore, the authors say that most of the plastic probably comes from more distant locations, brought in via rain and high altitude winds.


Image by Bronisław Dróżka from Pixabay
Image by Bronisław Dróżka from Pixabay


Trying to understand the patterns and processes of how microplastics move around the globe is only just beginning. However, pieces of plastic small enough to sail into the atmosphere and end up in the deepest ocean trenches or in very remote terrestrial environments are virtually impossible to clean up.

The only viable solution is to produce less single-use plastic in the first place! And, by the way, don´t blame the plastic; blame the plastic waste instead.


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Allen et al. [2019]. Atmospheric transport and deposition of microplastics in a remote mountain catchment, Nature Geoscience 12, 5, 339 – 344

Brahney et al. [2020]. Plastic rain in protected areas of the United States, Science 368, 1257 – 1260

Dameris [2010]. Depletion of the Ozone Layer in the 21st Century, Angewandte Chemie 49, 489 – 491

Fox [2019]. Airborne microplastics found atop France’s remote Pyrenees mountains, Science, posted in Climate, doi:10.1126/science.aax6817

Geyer et al. [2017]. Production, use, and fate of all plastics ever made, Science Advances 3, e1700782, pp. 5

Pipkin [2020]. Microplastics: The grand reach of our tiny plastics problem, The Abell Report 33, 2, pp. 24

Rochman [2018]. Microplastics research—from sink to source, Science 360, 6384, 28 – 29

Sladen et al. [1966]. DDT residues in Adelie penguins and a crabeater seal from Antarctica, Nature 210, 5037, 670 – 673


Use your brain before it is destroyed by chemical cocktails

In March 2019, the European Food Safety Authority (EFSA) published a note entitled EFSA adopts a specific methodology for assessing chemical mixtures. The new methodological framework will provide EFSA scientists with the tools that will enable them to adopt, where appropriate, a specific approach to address mixtures of chemical contaminants. This approach will complement the current European Union regulatory provisions for the assessment of contaminant mixtures known as contaminant cocktails. Two months ago, EFSA published a report on the cumulative risks of pesticides. The pesticide residues we absorb when we eat fruit and vegetables remain far below individual toxicity thresholds. And yet, several experts believe that synergistic effects cannot be excluded. People are undeniably exposed to a wide variety of contaminants, some of which greatly compound the effect of others!

However, not only pesticide cocktails constitute a threat to public health. The molecules released by packaging and food contact materials could be the predominant sources of contamination of our foodstuffs. About fifteen years ago, Grob et al. [2006] arrived at the frightening conclusion that several tens of thousands of substances migrate into the packaged food in amounts exceeding the threshold of toxicological concern. These high migrant numbers were ultimately confirmed by other scientists [Rather et al. 2017; Geueke et al. 2018].

And according to the Food and Agriculture Organization of the United Nations, we should be worried about another cocktail [Eskola et al. 2019]. Toxic compounds produced by different types of fungi, or mycotoxins, contaminate 25 % and more of the world’s agricultural products. Aflatoxins, deoxynivalenol and zearalenone are well known culprits, but several hundreds of mycotoxins have been discovered in our diet. A mycotoxin contamination is bad enough, but the situation becomes even more disastrous when mycotoxins occur in mixtures containing pesticides [Eze et al. 2018]. Can anybody deny the presence of pesticide traces in our food?

There is no eluding the questions which are so important to so many people. Is it healthy? What impact do these products have on our health? An original study by the national agency for food, environmental and occupational health in France identified the main diets and their inherent contaminant cocktails, with each cocktail containing 11 to 19 contaminants [Traoré et al. 2016 & 2018]. The contaminant classes are heavy metals, mycotoxins, polycyclic aromatic hydrocarbons, pesticides and xenobiotics. A follow-up study evaluated the effects of individual contaminant molecules as well as their characteristic mixtures or cocktails [Kopp et al. 2018]. Obviously, the cocktail effects often exceeded the sum of individual effects. The contaminants reinforced one another. The conclusion that was reached by the researchers is anything but surprising: the effects of contaminants are synergistic.

Are these contaminants truly pathogenic? Is the “machinery” of the body not capable of repelling their attacks? Scientific experts point to the link with the striking increase in lifestyle diseases, such as obesity, type 2 diabetes, infertility, behavioural and cognitive problems, food allergies, and diseases associated with smoking (tobacco smoke is a complex cocktail of chemicals, many of which are endocrine disruptors) and alcohol and drug abuse [Boukris 2014; Trasande 2019]. The increased risk of morbidity results from chemical contaminants in our food; substances with the most obvious health effects are pesticides, flame retardants, fluorinated surfactants or plasticizers and bisphenols. At first, it was thought that these products must persist in the body to cause damage. It is now generally accepted however that even if the body rapidly excretes the contaminants, they leave lasting effects. Often the discernible effect occurs only years later. Worse still, it can even be passed on to the next generation(s). This is called the hit-and-run impact. Our future looks bleak: many chemical substances are harmful and more so even when they are associated with other contaminants.

Protecting ourselves from contaminants is a great challenge and a task that should not be underestimated. Human activities have introduced thousands of tonnes of chemicals into the environment even though it was no secret that humans would behave like absorbent sponges and store the contaminants in their blood. What can we do to remedy this global catastrophe? What can we do to defuse the ticking time bomb that has been inserted into our bodies without our consent? There is no simple answer and no miracle solution. A thorough cleaning – the complete degradation of persistent pollutants, micro- and nanoplastics, and other cocktails – will take much longer than a few weeks or months, and it may even last forever.

It is therefore imperative that we  address the major exposure route and guarantee the safety of our food. Governments and agencies for the safety of the food chain must monitor the quality of our foods and beverages; they are responsible for the quality control of products on the market, for necessary chemical and microbiological testings and for risk assessment. This requires permanenty updating techniques. More than ever do we need to pay attention to the metabolic reactions, to the potential toxicity of the whole diet. Molecule-by-molecule analyses to determine the concentrations of target substances and comparing these concentrations to toxicological reference values ​​is therefore of little use. Steps should be taken to develop dedicated mixtures exposure assessment [Kortenkamp 2009; Grob 2017]. The approach that is currently adopted almost everywhere is based on individual substance assessments and does not provide any information on the reaction(s) a substance can cause in the presence of a complex chemical cocktail.

However, emerging techniques, such as bio-analytical methods [Denison et al. 2004; Veyrand et al. 2017], multi-residue analyses [Nannou et al. 2019] and in silico techniques [Van Bossuyt et al. 2017], offer promising prospects. Combining them with molecule-by-molecule analyses will allow us to identify the most dangerous contaminants and determine the harmful effects of the cocktail. For a secure future, we shall need to use a cocktail of techniques to tackle the cocktail of contaminants [Goeyens 2020].

Official bodies naturally have an essential responsibility. Nevertheless, consumers also have an important part to play. Let us now turn away from ultra-processed foods – too sweet or too salty – and increase our consumption of whole grains, fruit and vegetables, nuts and legumes. This will boost our quality of life and help us overcome viral diseases such as COVID 19. Also, the share of hospitalised patients will fall since treacherous viruses will find fewer victims to contaminate, i.e. those already suffering from pre-existing comorbidities caused by poor quality food consumption [vom Saal & Cohen 2020].

Our food is often a stubborn supplier of invisible contaminants. Ensuring food security is a most effective way of dealing with the crisis. Looking the other way would be a huge mistake! Toxins affect our bodies, but worse still, there is now every reason to believe that contaminants also affect the brain [Bellinger 2012; Lam et al. 2017; Gaylord et al. 2020].

Could it really be that we are heading for a future with fewer great minds?

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Bellinger[2012]. A strategy for comparing the contributions of environmental chemicals and other risk factors to neurodevelopment of children, Environmental Health Perspectives 120, 4, 501 – 507

Boukris [2014]. Demain, vieux, pauvres et malades! Éditions du Moment, pp. 225

Denison et al. [2004]. Recombinant cell bioassay systems for the detection and relative quantitation of halogenated dioxins and related chemicals, Talanta 63, 5, 1123 – 1133

Eze et al. [2018]. Toxicological effects of regulated mycotoxins and persistent organochloride pesticides: In vitro cytotoxic assessment of single and defined mixtures on MA-10 murine Leydig cell line, Toxicology In Vitro 48, 93 – 103

Gaylord et al. [2020]. Trends in neurodevelopmental disability burden due to early life chemical exposure in the USA from 2001 to 2016: A population-based disease burden and cost analysis, Molecular and Cellular Endocrinology 502, 110666

Geueke et al. [2018]. Food packaging in the circular economy: Overview of chemical safety aspects for commonly used materials, Journal of Cleaner Production 193, 491 – 505

Goeyens [2020]. Keeping Cocktail Effects Under Control is the Number One Challenge for the 21st Century, EC Nutrition 15, 2, pp. 3

Grob et al. [2006]. Food contamination with organic materials in perspective: packaging materials as the largest and least controlled source? A view focusing on the European situation, Critical reviews in food science and nutrition 46, 7, 529 – 535

Grob [2017]. The European system for the control of the safety of foodcontact materials needs restructuring: a review and outlook for discussion, Food Additives & Contaminants: Part A, 34, 9, 1643 – 1659

Kopp. et al. [2018]. Genotoxicity and mutagenicity assessment of food contaminant mixtures present in the French diet, Environmental and Molecular Mutagenesis 59, 8, 742 – 754

Kortenkamp [2009]. Ten years of mixing cocktails: a review of combination effects of endocrine-disrupting chemicals, Environmental health perspectives 115, Suppl 1, 98 – 105

Lam et al. [2017]. Developmental PBDE exposure and IQ/ADHD in childhood: a systematic review and meta-analysis, Environmental health perspectives 125, 8, 086001, pp. 20

Nannou et al. [2019]. Analytical strategies for the determination of antiviral drugs in the aquatic environment, Trends in Environmental Analytical Chemistry, e00071

Rather et al. [2017]. The sources of chemical contaminants in food and their health implications, Frontiers in pharmacology 8, 830, pp. 8

Traoré et al. [2016]. To which chemical mixtures is the French population exposed? Mixture identification from the second French Total Diet Study, Food and Chemical Toxicology 98, 179 – 188

Traoré et al. [2018]. To which mixtures are French pregnant women mainly exposed? A combination of the second French total diet study with the EDEN and ELFE cohort studies, Food and Chemical Toxicology 111, 310 – 328

Trasande [2019]. Sicker, Fatter, Poorer: The Urgent Threat of Hormone-Disrupting Chemicals to Our Health and Future . . . and What We Can Do About It, Houghton Mifflin Harcourt, pp. 221

Veyrand et al. [2017]. Integrating bioassays and analytical chemistry as an improved approach to support safety assessment of food contact materials, Food Additives & Contaminants: Part A 31, 10, 1807 – 1816

Van Bossuyt et al. [2017]. Safeguarding human health using in silico tools, Archives of Toxicology 91, 2705 – 2706

vom Saal & Cohen [2020]. How toxic chemicals contribute to COVID-19 deaths, Environmental Health News, April 17,

What lies ahead after the coronavirus?

COVID-19, we are talking about nothing else!
As the number of confirmed cases of COVID-19 surges past 2.2 million globally and deaths surpass 150000, clinicians and pathologists are struggling to understand the damage wrought by the coronavirus as it tears through the body. They are realizing that although the lungs are ground zero, its reach can extend to many organs including the heart and blood vessels, kidneys, gut, and brain [Wadman et al. 2020].

The virus tears through the body

Its reach can extend to many organs. This is a very disconcerting message [Ledford 2020; Wadman et al. 2020].

The novel coronavirus can enter the nose and throat. It finds a home in cells that are rich in a cell-surface receptor called angiotensin-converting enzyme 2 (ACE2). Throughout the body, the presence of ACE2, which normally helps regulate blood pressure, marks tissues that are vulnerable to infection, because the virus requires that receptor to enter a cell. Once inside, the virus hijacks the cell machinery, making copies of itself and invading new cells.

If the immune system fails to beat back the virus during the initial phase, it may reach the windpipe and attack the lungs. The lungs make sure the oxygen is carried to the rest of the body, but as the immune system is busy waging war against the invader, this healthy oxygen transfer is disrupted. Front-line white blood cells release inflammatory molecules called chemokines, a family of small cytokines, which in turn summon more immune cells that target and kill virus-infected cells, leaving behind a mash of fluid and dead cells − pus. This is the underlying pathology of pneumonia, with its corresponding symptoms of cough, fever, and rapid and shallow respiration. Some COVID-19 patients recover with no more support than oxygen breathed in through nasal prongs, while others deteriorate, often quite suddenly.

A number of infected patients develop heart-related problems either for no apparent reason or as a complication of a pre-existing cardiac disease. A report dating back to the early days of the pandemic describes the extent of cardiac injury among patients hospitalised with COVID-19 in Wuhan [Huang et al. 2020]. Moreover, according to a retrospective study by Shi et al. [2020] many hospitalised patients in Wuhan suffered from kidney failure. Those with acute kidney injury were more than 5 times as likely to die as COVID-19 patients without the condition. Another striking set of symptoms in COVID-19 patients concerns the brain and central nervous system (CNS). While neurological manifestations of COVID-19 have not yet been studied appropriately, it is highly likely that some of these patients, particularly those who suffer from a severe illness, have CNS involvement and neurological manifestations [Asadi-Pooya & Simani 2020]. A growing body of evidence also suggests that the new coronavirus, as is the case with its cousin SARS, can infect the lining of the lower digestive tract, where the crucial ACE2 receptors are abundant [Ng & Tilg 2020]. But the intestines is not where the march of the disease through the body ends. For example, up to one-third of hospitalised patients develop conjunctivitis − pink, watery eyes − although it is not clear whether the virus directly invades the eye. And other reports suggest liver damage. More than half COVID-19 patients hospitalised in two Chinese centres had elevated levels of enzymes indicating injury to the liver or bile ducts [Wadman et al. 2020].

Do face masks really reduce coronavirus spread?

Several experts suggest that it might not be the virus alone that rages through the body and kills. It may well be the case that an overactive immune response also contributes. Some critically ill patients with COVID-19 had high blood levels of cytokines, which can trigger a disastrous overreaction of the immune system known as “cytokine storm”. Cytokines are chemical signaling molecules that guide a healthy immune response. In a cytokine storm, however, levels of certain cytokines soar far beyond what is needed and immune cells start to attack healthy tissues. Blood vessels leak, blood pressure drops, clots form, and catastrophic organ failure can ensue.

Many people living in the Western world suffer from one more chronic diseases

These chronic diseases − obesity, diabetes, respiratory diseases, liver, kidney and cardio-vasular diseases, auto-immune diseases, and many others − involve disruption of the normal immune function, resulting in inflammation. Chronic inflammation primes the body to react with a heightened response to immune system insults such as COVID-19 infections. A terrifying observation, all the more since these chronic diseases have been steadily increasing over the past 50 years in association with the dramatic increase in chemical production for use in plastics, construction materials, pesticides, personal care products, furniture, cookware, food packaging, textiles, and many other products that are steadily infiltrating every aspect of human life.

Many of these chemicals are categorised as endocrine disrupting chemicals (EDC) that can interfere with the normal functioning of hormones involved in cell communication, including regulating immune responses and inflammation. We are exposed to such chemicals through a myriad of consumer products, e.g. our drinking water and highly processed food. However, the dangers posed by continuous exposure to EDC [Yang et al. 2006] are insufficiently acknowledged.

vom Saal & Cohen [2020] conclude, in their Environmental Health News communication, that the combination of EDC and insufficient amounts of antioxidants and micronutrients create the perfect setting for an abnormal inflammatory response. Moreover, several of the nutrients (e.g. zinc, vitamin B3, vitamin C, vitamin D) and antioxidants from fruits and vegetables are among the many therapeutic interventions currently being looked at to reduce the length and severity of coronavirus infections.

COVID-19 confirms my worst fears!

As it happens, I have already repeatedly expressed my concern about the ubiquitous nature of chemical contamination and the consequences of our exposure to it. And to make matters worse, we are not properly prepared to tackle the chemical contamination problem [Goeyens 2020].

Belgian politicians recently told newspaper journalists that scientists were being given too much room to maneuver. I believe − and I may not be the only one − that science and a genuine desire to protect public health will be more than necessary in the post-corona era. With steadily increasing chronic diseases, it is hardly possible not to establish a link between chemical contaminants and disease. We have to redress this global disaster situation and defuse the ticking time bomb that has been inserted into our bodies without our consent. We must immediately stop polluting our planet. Let us make that our first priority!

We were not intended by providence to rule the world. The biosphere does not belong to us; we belong to it [Wilson 2016].

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Asadi-Pooya & Simani [2020]. Central nervous system manifestations of COVID-19: A systematic review, Journal of the Neurological Sciences 413, 116832, pp. 4.
Goeyens [2020]. Keeping Cocktail Effects Under Control is the Number One Challenge for the 21st Century, EC Nutrition 15, 2, 01 – 03
Huang et al. [2020]. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China, Lancet 395, 497 – 506
Ledford [2020]. How does COVID-19 kill? Uncertainty hampers doctors´ability to choose treatments, Nature 580, 311 – 312
Ng & Tilg [2020]. COVID-19 and the gastrointestinal tract: more than meets the eye, Gut, gutjnl-2020-321195, pp. 2
Shi et al. [2020]. Clinical characteristics of 101 COVID-19 nonsurvivors in Wuhan, China: a retrospective study, medRxiv preprint, doi:
vom Saal & Cohen [2020]. How toxic chemicals contribute to COVID-19 deaths, Environmental Health News, April 17,
Wadman et al. [2020]. How does coronavirus kill? Clinicians trace a ferocious rampage through the body, from brain to toes, Science DOI: 10.1126/science.abc3208
Wilson [2016]. Half-earth, Liverlight Publishing Corporation, pp. 259
Yang et al. [2006]. Endocrine disrupting chemicals: human exposure and health risks, Journal of Environmental Science and Health Part C 24, 2, 183 – 224

If you never buy packaged food, you can safely skip this article

Food contact and packaging articles are made up of a very large number of different food contact materials (FCM), each of them consisting of numerous food contact chemicals (FCC). Inevitably, FCC migrate from any type of material into the food and consequently, they are absorbed along with the food. Muncke et al. [2020] emphasise their concern based on scientific evidence that FCM and articles are a relevant exposure pathway for known hazardous substances as well as for a plethora of toxicologically uncharacterised chemicals.

There are flaws in our packaged food safety control

It has been quite a long time since Grob et al. [2006] called for a more realistic perception and more coherent legal measures because of sufficient evidence to suggest that FCC can be transferred from food contact materials and articles into food. It is now very clear that a substantial majority of the human population is exposed to a number of these chemicals. Indeed, for many FCC there is evidence of human exposure from biomonitoring.

When FCM regulations were first developed, it was generally assumed that low-level chemical exposures for example, the exposures below the toxicologically established no-effect level pose negligible risks to consumers, except for carcinogens [Crump 2011]. Recent scientific information however demonstrates that this assumption is not generally valid: for example, exposure to low levels of endocrine disrupting chemicals can generate adverse health effects [Kortenkamp 2007; Vandenberg et al. 2012; Gore et al. 2015]. Additionally, chemical mixtures play a predominant role in the development of adverse effects. Very often, cumulative effects exceed the sum of individual effects [Kortenkamp & Faust 2018; Goeyens 2019; Trasande 2019]. This is of the utmost importance: human exposure to chemical mixtures is the norm, but this is currently not considered when assessing health impacts of FCC. And another critical aspect for understanding the development of chronic diseases is the timing of exposures during foetal and child development [Heindel & Vandenberg 2015].
These highly important insights are insufficiently considered in the risk assessment of chemicals in general and of FCC in particular [Muncke et al. 2020 and references herein]. What we must do is look beyond the presence of one particular molecule or other and focus on the biological activity carcinogenicity, hormonal disruption, immunotoxic properties, neurobehavioural disturbances, etc. of the food and drinks we consume. Control agencies generally highlight the only molecule whose concentration exceeds the threshold value, but it is the mixture of highly different molecules that constitutes the threat.

In the European Union (EU), regulation EU 10/2011 on plastic materials and articles intended to come into contact with food includes a list of authorised substances for the manufacture of plastic materials and articles. It also sets acceptable maximum concentrations for some of the chemicals in the plastic FCM or in the packaged food (i.e. after migration). Many substances present in plastics, however, are non-intentionally added substances (NIAS). Even though regulations EU 10/2011 and EU 1935/2004 require a risk assessment of NIAS, this is a an almost impossible task. Identifying the NIAS is extremely demanding, if not impossible [Nerin et al. 2013; Pieke et al. 2018] as is studying the human health effects of NIAS. Most chemicals are currently unavailable as pure substances, and testing would prove too expensive.

So, what can we do?

People face an essentially un-quantified risk: food processing and packaging procedures have introduced high numbers of chemical contaminants into our diets, even though it is common knowledge that consumers will be serving as human sponges, soaking up and storing the contaminants in their bloodstreams. Is there anything we can do to defuse the ticking time bomb that has been inserted into our bodies without our consent? Muncke et al. [2020] highlight a number of points that will require the commitment of all the stakeholders concerned.

Our current risk assessment system is lagging behind and simply does not meet today’s living standards. Regulatory agencies should update whatever hazard and exposure data are necessary to produce safety standards based on current scientific know-how and understanding [Muncke et al. 2017 & 2020]. The current approach to pre-market, prospective risk assessment of chemicals in FCM is insufficient to ensure public health protection since it relies on assumptions that do not reflect contemporary scientific knowledge and is sometimes based on inadequate industrial self-monitoring. Even the GLP (good laboratory practice) labs do not always deliver reliable data [Pesticide Action Network 2020]. Since food packaging is an essential link in the food supply chain, regulatory mechanisms and risk assessment approaches should be updated and strengthened.

Endocrine disruption, as a specific hazard, is not routinely assessed for FCC. Several chemical migrants are known to be endocrine disruptors, however [Nerin et al. 2018]. Screening assays for endocrine disruption should be developed and/or optimised. Deriving a safe threshold may not be easy, however, since endocrine disrupting chemicals with non-monotonic dose responses do not only have increasing effects with increasing doses, but may also have effects in the low-dose range [Gore et al. 2015]. Also, the mixture toxicity of the overall migrate, i.e. all chemicals migrating from FCM, should be determined for a relevant set of hazards such as genotoxicity, mutagenicity, reprotoxicity, and endocrine disruption. This means that finished food contact articles should also be tested for their biological activity. Hence, regulators and other stakeholders should invest in research and development for fast or high-throughput approaches in order to screen the overall migrate (the complex contaminant mixture).

Finally, enforceable new regulations and sufficient resources for compliance control must be made available to authorities.

The current situation contradicts our dominant economic model based on unlimited growth and non-restrictive use of resources

Food packaging has become an important issue in discussions on circular economy [Ellen MacArthur Foundation 2017]. Priority projects include reuse, recycling or replacing plastic food packaging with alternative materials. Circular economy is a trilogy: (1) waste should become a starting material, (2) consumables should be non-toxic and possibly even beneficial, whereas durables should be reused, recycled or re-manufactered, and (3) energy sources should be sustainable, renewable by nature. Known hazardous chemicals should preferably not be used in the manufacture of food contact articles; moreover, if the use of known hazardous chemicals is essential and currently no suitable substitutes are available, research into developing safer alternatives should be a first priority. The development of safer alternatives could be based on current scientific principles, such as the Tiered Protocol for Endocrine Disruption [Shug et al. 2013].

For all of this, a multi-stakeholder dialogue should be established to identify solutions that are sustainable and focus on protecting humans and the environment while providing effective, efficient and affordable food packaging in a circular economy. Stakeholder needs are likely to vary between countries and cultural regions; diversity will not enable a “global” solution, but it must be respected.

Sustainable food packaging in the circular economy

It may only be achieved by combining efforts. All conflicting goals must be considered, and all stakeholders, including food and packaging manufacturers, recyclers, decision makers, civil society, and consumers must be involved [Geueke et al. 2018]. Why? Because food packaging is an issue that concerns us all.

It would be utterly wrong to claim that food packaging serves no useful purpose. Imagine taking home a litre of wine and a kilo of peanuts without being able to rely on any form of packaging.


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Crump [2011]. Use of threshold and mode of action in risk assessment, Critical Reviews in Toxicology 41, 8, 637 – 650
Ellen MacArthur Foundation [2017]. Towards the circular economy, pp. 99
Geueke et al. [2018]. Food packaging in the circular economy: Overview of chemical safety aspects for commonly used materials, Journal of Cleaner Production 193, 491 – 505
Goeyens [2019]. Good and bad food science – separating the wheat from the chaff, Academic and Scientific Publishers, pp. 366
Gore et al. [2015]. Executive summary to EDC-2: the Endocrine Society’s second scientific statement on endocrine-disrupting chemicals, Endocrine reviews 36, 6, 593 – 602
Grob et al. [2006]. Food Contamination with Organic Materials in Perspective: Packaging Materials as the Largest and Least Controlled Source? A View Focusing on the European Situation, Critical Reviews in Food Science and Nutrition 46, 1 – 7
Heindel & Vandenberg [2015]. Developmental origins of health and disease: a paradigm for understanding disease etiology and prevention, Current opinion in pediatrics 27, 2, 248, pp. 10
Kortenkamp [2007]. Ten years of mixing cocktails: a review of combination effects of endocrine-disrupting chemicals, Environmental health perspectives 115, Suppl 1, 98 – 105
Kortenkamp & Faust [2018]. Regulate to reduce chemical mixture risk, Science 361, 6399 224 – 226
Muncke et al. [2017]. Scientific challenges in the risk assessment of food contact materials, Environmental health perspectives 125, 9, 095001, pp. 9
Muncke et al. [2020]. Impacts of food contact chemicals on human health: a consensus statement, Environmental Health 19, 25, pp. 12
Nerin et al. [2013]. The challenge of identifying non-intentionally added substances from food packaging materials: A review, Analytica Chimica Acta 775, 14 – 24
Nerin et al. [2018]. A common surfactant used in food packaging found to be toxic for reproduction in mammals, Food and Chemical Toxicology 113, 115 –124
Pesticide Action Network [2020]. Fraud in German laboratory casts additional doubts on the 2017 re-approval of glyphosate and on the entire EU pesticide safety evaluation procedure,
Pieke et al. [2018]. Exploring the chemistry of complex samples by tentative identification and semiquantification: A food contact material case, Journal of Mass Spectrometry 53, 4, 323 – 335
Schug et al. [2013]. A new approach to synergize academic and guideline-compliant research: the CLARITY-BPA research program, Reproductive toxicology 40, 35 – 40
Trasande [2019]. Sicker, fatter, poorer, Houghton Mifflin Harcourt, pp. 221
Vandenberg et al. [2012]. Hormones and endocrine-disrupting chemicals: low-dose effects and nonmonotonic dose responses, Endocrine reviews 33, 3, 378 – 455

Insect fat: could it replace butter in cakes and cookies?

Something weird is going on
The fear and revulsion you may feel towards insects was probably instilled in you when you were very young, but the feeling is now beginning to dissipate. The thought of holding a grasshopper, a praying mantis, or a caterpillar no longer puts you off. More so even, if you are researching entomophagy, even the idea of eating bugs is becoming more acceptable. It is surprising how easily fear and disgust can be overcome if you really think about what actually causes your negative reactions. Insects are touted for their nutritional benefits and low environmental footprint. Quite a few varieties, including crickets, grasshoppers and mealworms, are high in protein, fat and fibre, as well as minerals such as calcium, iron, and phosphorus. Some people even say they are very tasty. For all their seemingly good qualities, many Western consumers are still not keen to include edible insects as part of their diet. Not all consumers however find insects disgusting and several start-ups and social entrepreneurs have identified this opportunity in the market [Videbæk & Grunert 2020].

Most successful product launches would probably use insects as ingredients
Quite a few studies have already shown that our acceptance of food with insects increases with decreasing insect visibility. Scientists at Gent University now also believe that boosting the development of insect ingredients will significantly increase their consumption. They surveyed reactions to cakes, cookies, and waffles containing an ingredient made from insect fat [Delicato  et al. 2020].

Black Soldier Fly ( freely available on )

Black Soldier Fly larvae fat (BSF LF) contains about 70 % saturated fatty acids, with lauric acid accounting for more than 40 %. Lauric acid or dodecanoic acid is a medium-length long-chain fatty acid. BSF LF is solid at room temperature and more digestible than long chain fatty acids. It also prevents the growth of several gram-positive bacteria, fungi and viruses [Dayrit 2015]. As is  he case with high quality farm butter, BSF LF is thought to enhance baked goods in terms of tenderness, mouthfeel, and gluten structure reduction.

Functionality, sensory perception and acceptance of BSF LF in bakery products has to be explored
Sensory and emotional profiling, willingness to pay, liking and product preference were examined by a total of 344 respondents for cakes, cookies, and waffles. Each of the bakery products was respectively formulated with 0 %, 25 % and 50 % BSF LF. According to the research findings, BSF LF can replace 25 % of butter in these bakery products without changing the overall food experience and liking. In waffles – and potentially in a few other bakery products with direct heat content – up to 50 % could be substituted without affecting consumer acceptance. However,  formulations with 50 % BSF LF were associated with sensory challenges. It was observed that off-flavour, rancid aroma, rancid taste and bad aftertaste were more closely related to the  formulation with 50 % BSF LF. A higher percentage of BSF LF in food could possibly be achieved using refined BSF LF. Regarding texture and colour, the investigation by Delicato et al. [2020]  found they were hardly affected. This indicates that BSF LF provides a similar structure and functionality to butter when used in bakery products. To include insect fats in bakery products could lower the barriers for consumers to include insect-based foods in the rest of their diet. Incidentally, there are already plenty of examples: butter cookies based on ground beetles [Tan et al. 2015], tortilla made with cricket flour [Gmuer et al. 2016], beef stew and brownies with not visible mealworms added [Tan et al. 2016], and many more.

So what do we think about the safety of insect-based food products?
Farmed insects as well as parts of insects for food fall under the definition of novel food in the EU. This means that insect products require pre-market authorisation from the European Food Safety Authority. Authorisation is dependent on the completion of a full scientific dossier demonstrating that the novel food is safe. Even if none has yet been approved, a number of applications is currently under review, including an application for black soldier fly meal [Southey 2020]. Insect meal and insect lipids are two different products, meaning that they require different safety evaluations. One of the main differences is related to allergenicity, since allergies are predominantly caused by proteins, which are present in meal. This risk of allergenicity of lipids is very low, since only traces of protein are present in crude oils and fats. Moreover, the risk completely disappears in refined lipids.

Does the idea of eating insects bug you?
Think about it: the United Nations predicts that, if current trends continue, the world’s population will reach ~9.8 billion by 2050. As a result, global demand for food and feed is expected to increase by 70 %, putting additional pressure on already overexploited agricultural resources. Global demand for meat in particular will continue to increase as dietary habits in developing countries change, due to rapid urbanisation and economic growth. Moreover, the oceans are already overfished and climate change will have a profound impact on food production. Meanwhile, nearly one billion people worldwide suffer from chronic food deprivation. So not to do anything is simply not an option. Among the possible solutions, one is slowly catching the public’s attention: eating insects.


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Dayrit [2015]. The properties of lauric acid and their significance in coconut oil, Journal of the
American Oil Chemists' Society 92, 1, 1 – 15
Delicato et al. [2020]. Consumers’ perception of bakery products with insect fat as partial butter
replacement, Food Quality and Preference 79, 103755, pp. 9
Gmuer et al. [2016]. Effects of the degree of processing of insect ingredients in snacks on expected
emotional experiences and willingness to eat, Food Quality and Preference 54, 117 – 127
Southey [2020]. Insect fat the new butter replacement? Researchers see potential in bakery
products, available on
Tan et al. [2015]. Insects as food: Exploring cultural exposure and individual experience as
determinants of acceptance, Food Quality and Preference 42, 78 – 89
Tan et al. [2016]. The influence of product preparation, familiarity and individual traits on the
consumer acceptance of insects as food, Food Quality and Preference 52, 222 – 231
Videbæk & Grunert [2020]. Disgusting or Delicious? Examining Attitudinal Ambivalence towards
Entomophagy among Danish Consumers, Food Quality and Preference 103913, pp. 12

Scientists have tried to do things the nice way but you, my dear policymakers, are still not prepared to take the message on board

In 2018, total greenhouse gas emissions in Belgium amounted to 118.3 megatons of CO2 equivalents, a slight increase of 0.28 per cent compared to 2017

I can only assume that you did not read this alarming message that was published in several Belgian newspapers. And yet, a substantial decrease in greenhouse gas emissions is needed to live up to our ambitious pledge. It required a great deal of effort to achieve small progress before 2018, but now it appears that the figures are beginning to rise again. Increases could be due to a number of nuclear power plants that were shut down in 2018 []. Whatever the reasons may be, Belgium is simply not on track to meet European climate ambitions. It seems that Belgian governments – Belgium has six parliaments and six governments – lack the will and the way.

Global Carbon Dioxide emissions [Ritchie & Roser 2020]
available on

Globally, the primary sources of greenhouse gas emissions are electricity and heat, agriculture, transportation, forestry and manufacturing [Rockström et al. 2020]. The global food system is a predominant greenhouse gas emitting sector in the world [IPCC 2019a&b] and by far the largest cause of biodiversity loss, terrestrial ecosystem destruction [IPBES 2019], freshwater consumption, and waterway pollution because of the huge overuse of synthetic fertilizers and pesticides [Rockström & Karlberg 2010]. The food system holds the stability of humanity in its grips. Can the predicted rise in global food demand by 2050 be met sustainably? The answer must be yes, but growth and sustainability do not come automatically. Fisher [2018] recommends a combination of interventions to tackle the associated environmental challenges.


There must be a significant improvement in the quality of our food

Unhealthy food is the world’s biggest killer [GBD 2017 Diet Collaborators 2019], with diet-related chronic diseases estimated to be responsible for 11 million premature deaths in 2017 alone. Moreover, 255 million disability-adjusted life-years (DALY) were attributable to dietary risk factors. High intake of sodium (3 million deaths and 70 million DALY), low intake of whole grains (3 million deaths and 82 million DALY), and low intake of fruits (2 million deaths and 65 million DALY) are the leading dietary risk factors for deaths and DALY.

The global food system is obviously letting us down! The system is not only responsible for polluting the natural environment, but falls short of providing us with healthy and diversified food. To make matters worse, escalating obesity, diabetes, learning disorders, autism, infertility, and food allergies result from endocrine disrupting chemicals in our food, but also in our homes and personal care products [Trasande 2019].

An urgent shift in mindset is therefore required to recognize that agricultural ecosystems are huge biomes of the Earth that have an enormous impact on the planet’s elemental cycles. Contemporary agriculture was able to develop through the benign climatic conditions and abundant biodiversity of the Holocene. During the current Anthropocene [Crutzen & Stoermer 2000; Crutzen 2002], however, the food system became a predominant driver of our contemporary Earth trajectory that could trigger a cascade of interacting non-linear processes propelling the planet towards a radically different climatic state [Svingen & Vinggaard 2016; Rockström et al. 2020]. There is little doubt that this will impact the future of humanity!


What is likely to happen

It is now clearly evidenced that warming beyond 1.5 C would put us in the danger zone [IPCC 2019a]. The world has already warmed by 1 C above pre-industrial levels; at 1.5 C tropical coral reefs are very likely to collapse. At 2 C, the Arctic summer sea ice would disappear and the Greenland Ice Sheet could disintegrate; several glaciers of the West Antarctic Ice Sheet might already have passed tipping points, contributing to over two metres of unstoppable sea-level rise in the long-term [IPCC 2019b]. The oceans have buffered the effects of global warming by absorbing more than 90 % of human-caused excess heat. However, social and environmental costs are mounting and, as oceans grow warmer, more acidic and less productive, coastal extreme events and sea-levels are on the rise [IPCC 2019b]. The powerful Storm Gloria, which battered much of eastern Spain and southern France, is seen as a harbinger of more hardship and calamity. And Ciara, the storm that recently assailed the British Islands and the Benelux came as yet another reminder of the impending disaster.

The diversity of species and ecosystems is now declining faster than at any time in human history [IPBES 2019]. Moreover, there is convincing evidence that tipping elements are connected and can trigger cascading effects. Steffen et al. [2018] explore the risk that self-reinforcing feedbacks could push the Earth System toward a planetary threshold that, if crossed, could prevent stabilization of the climate at intermediate temperature rises and cause continued warming on a “Hothouse Earth” pathway even as human emissions are reduced. Crossing the threshold would lead to a much higher global average temperature than at any interglacial age in the past 1.2 million years and to sea levels significantly higher than at any time in the Holocene. For example, Arctic sea-ice melt amplifies regional warming, accelerating Greenland ice sheet melt, which in turn may have contributed to the recent 15 % slowdown in the Atlantic Meridional Overturning Circulation [Caesar et al. 2018]. This circulation is connected to both regional rainfall dynamics in the Amazon and the West African monsoon [Parsons et al. 2014]. A further slowdown potentially triggers drought, amplifies global warming and generates food shortages. Without a major transformation across sectors and scales, we risk crossing points of irreversibility that will threaten the Earth system as we know it.


History began when humans invented gods, and will end when humans become gods

These are the words of Yuval Noah Harari [], who was recently awarded an honorary doctorate by my university, the Vrije Universiteit Brussel. In her speech, Rector Caroline Pauwels praised the renowned author of Sapiens, Homo Deus and 21 Lessons for the 21st Century, as a historian who looks beyond borders and not only reports history, but builds on it: In Harari we have an outstanding guide to show us the possibilities and dangers of future developments.

The ceremony was attended by a large audience, which of course can only be seen as a good thing. But attending official events is obviously not enough. Much better to read and reflect on what thinkers of the calibre of Harari have written and to spread their message.

The emergence of essentially global problems, such as the melting of the polar caps, nibbles on the last leftovers of the independent states. No sovereign state will ever be able to combat global warming on its own [Harari 2016].

To encourage recycled office furniture for the Flemish administration is just about as useful as a plaster cast on a wooden leg! Any action plan should include a programme of consultation and cooperation across a whole range of areas, and procrastination must be avoided at all cost.

It is high time we stopped playing games!


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Caesar et al. [2018]. Observed fingerprint of a weakening Atlantic Ocean overturning circulation, Nature 556, 191 – 196

Crutzen [2002]. Geology of mankind: the Anthropocene, Nature 415, 23

Crutzen & Stoermer [2000]. The Anthropocene, Global Change Newsletter 41, 17 – 18

Fisher [2018]. Transforming the global food system, Nature 562, 501 – 502

GBD 2017 Diet Collaborators [2019]. Health effects of dietary risks in 195 countries, 1990–2017: a systematic analysis for the Global Burden of Disease Study, Lancet 393, 1958 – 1972

Harari [2016]. Sapiens, Thomas Rap, pp. 462

IPBES [2019]. Nature’s Dangerous Decline ‘Unprecedented’; Species Extinction Rates ‘Accelerating’, available on

IPCC [2019a]. Special Report on Global Warming of 1.5°C, available on

IPCC [2019b]. Special Report on the Ocean and Cryosphere in a Changing Climate, available on

Parsons et al. [2014]. Influence of the Atlantic Meridional Overturning Circulation on the monsoon rainfall and carbon balance of the American tropics, Geophysical Research Letters 41, 146 – 151

Ritchie & Roser [2020]. CO₂ and Greenhouse Gas Emissions, published online at, retrieved from

Rockström & Karlberg [2010]. The Quadruple Squeeze: Defining the safe operating space for freshwater use to achieve a triply green revolution in the Anthropocene, Ambio 39, 3, 257 – 265

Rockström et al. [2020]. Planet-proofing the global food system, Nature Food 1, 1, 3 – 5

Steffen et al. [2018]. Trajectories of the Earth System in the Anthropocene, Proceedings of the National Academy of Sciences 115, 33, 8252 – 8259

Svingen & Vinggaard [2016]. The risk of chemical cocktail effects and how to deal with the issue, Journal of Epidemiology and Community Health 70, 322 – 323

Trasande [2019]. Sicker, fatter, poorer, Houghton Mifflin Harcourt, pp. 208

How do you respond to political intransigence?

2019 was another tough year for the environment [Castelvecchi et al. 2019]

Up to one million plant and animal species now face extinction owing to habitat destruction and/or climate change, warns a recently published report of the Intergovernmental Science–Policy Platform on Biodiversity and Ecosystem Services (IPBES). The overwhelming evidence of the IPBES Global Assessment, from a wide range of different fields of knowledge, presents an ominous picture, said IPBES Chair, Sir Robert Watson. The health of ecosystems on which we and all other species depend is deteriorating more rapidly than ever. We are eroding the very foundations of our economies, livelihoods, food security, health and quality of life worldwide [IPBES 2019].

Moreover, the Intergovernmental Panel on Climate Change (IPCC) special report calls for drastic efforts to curb our demand for agricultural land and to promote the adoption of a plant-based diet for humans. Without such action, the IPCC says, governments will fall short of their collective goals under the 2015 Paris climate accord, in which nations agreed to limit global warming to no more than 2 C above pre-industrial levels. The IPCC Special Report on the Ocean and Cryosphere in a Changing Climate [IPCC 2019], approved on the 24th of September 2019 by the 195 IPCC member governments, provides new evidence for the benefits of limiting global warming to the lowest possible level in line with the goal that governments set themselves in the 2015 Paris Agreement. Urgently reducing greenhouse gas emissions can limit the scale of ocean and cryosphere changes.

The open sea, the Arctic, the Antarctic and the high mountains may seem far away to many people, said Hoesung Lee, Chair of the IPCC, but we depend on them and are influenced by them directly and indirectly in many ways – for weather and climate, for food and water, for energy, trade, transport, recreation and tourism, for health and wellbeing, for culture and identity… If we reduce emissions sharply, consequences for people and their livelihoods will still be challenging, but potentially more manageable for those who are most vulnerable, Lee said. We increase our ability to build resilience and there will be more benefits for sustainable development.


Unfortunately political trends seemed to be moving in the opposite direction

The Brazilian president, Jair Bolsonaro, took over the helm in January with a fiery anti-environmental agenda. He slashed federal funding for science and in July he even accused his own government’s scientists of lying about a deforestation peak in the Amazon.

In the United States (US), President Donald Trump continued his efforts to dismantle environmental regulations. In June, the US Environmental Protection Agency (EPA) finalised a plan to relax limits on greenhouse gas emissions from power plants, eviscerating one of former president Barack Obama’s flagship climate policies [Tollefson 2019]. In August, the EPA followed suit with a proposal to freeze fuel-efficiency standards for automobiles. In addition, the president announced that his administration was revoking a decision by California’s authority to introduce stricter car emission rules than those issued by federal regulators. Critics had claimed that the move would result in less fuel-efficient cars that would result in more planet-heating pollution. And in November, the administration began the official process of pulling the United States out of the Paris agreement. The Trump administration had already announced that it planned to pull out in its first year in office, but a country cannot formally even begin to withdraw until three years after the agreement goes into force. As far as the United States was concerned, that was November 4, 2019. Even so, the US is not quite out yet. It takes exactly one extra year for the withdrawal notice to become official, meaning that the US will formally pull out of the Paris agreement one day after the 2020 US presidential election!

The ambition of the Belgian climate policy is inversely proportional to the number of delegates to COP25 in Madrid. Frans Timmermans, Executive Vice-President responsible for the European Green Deal, was not impressed with the Belgian plan: all Member States of the European Union have subscribed to the Paris climate targets and must make national plans to achieve those targets. And that also applies to Belgium and Flanders (Alle lidstaten van de Europese Unie hebben de klimaatdoelstellingen van Parijs onderschreven en moeten nationale plannen maken om die doelstellingen te realiseren. En dat geldt ook voor België en Vlaanderen). In the margins of the climate summit in Madrid, our country was awarded the unenviable Fossil of the Day prize. The prize is awarded by the global network of NGOs, Climate Action Network, to the country that performs worst at the UN Climate Talks. Was the Belgian delegation embarrassed? Not that we could notice.

The end result of the Madrid summit is poor to say the least and comes nowhere near fulfilling the necessary requirements. Apart from the European Union ‒ and even though the European action plan still has to be implemented ‒ no major greenhouse gas emitter has announced a serious plan to achieve carbon dioxide neutrality in 2050. Jean-Pascal Vanypersele, the respected Belgian climatologist, concludes that what should have been the summit of ambition eventually became the summit of disappointment.


Dutch judge, Kees Streefkerk, brings some light into darkness

In May, the Dutch Supreme Court heard the government’s appeal against a lawsuit brought by the Urgenda Foundation, a citizens’ climate organisation that in the lower courts has successfully argued that the Dutch government must do more to combat climate change. On Friday, December 20, the Supreme Court of the Netherlands ordered the Dutch government to cut the nation’s greenhouse gas emissions by 25 per cent of 1990 levels by the end of 2020. It is the first time a nation has been required by its courts to take action against climate change. Because of climate change, the lives, well-being and living circumstances of many people around the world, including in the Netherlands are being threatened, the Chief Justice said in commenting the decision. The decision made by the Supreme Court is final: … The Supreme Court decides that the order to the Dutch state, issued by the district court and confirmed by the court of appeal, is definitively upheld… Given the presence of a large number of foreign attendees, Streefkerk passed judgement in English.

It was a historic moment. Never before had a judge forced a country to pursue a stricter climate policy. Dutch Prime Minister, Mark Rutte, did not wish to give any guarantees and preferred to adopt a non-committal attitude and talk about “a decent job in a short time” (een behoorlijke klus in korte tijd).


Stop the Greta- and Anuna-bashing

Despite four decades of warnings, far too little has happened to stop global warming. Our greenhouse gas emissions continue to rise; the physical process we ourselves started has gone on undisturbed. Since the beginning of the new millenium, the list of successive heat, drought and flood records has become much too long for us to continue to ignore global warming. Natural disasters were always there, but global warming has made them more frequent and more extreme. We can see its effects everywhere, also in Belgium. More and more tons of sand are being used to protect our coast against rising sea levels. Belgian farmers are having to cope with more and more extreme droughts and downpours that destroy their crops.

Anyone who persists in claiming that we can solve the problem later, that we have the technology and that we should not be so alarmist is unrealistic and unethical [Debusschere 2019].


I would have loved to wish you all a happy, care-free New Year

However, in a world that continues to generate misfortune and disaster, my New Year wishes can only sound a little hollow.


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Castelvecchi et al. [2019]. 2019 in review, Nature 576, 350 – 353

Debusschere [2019]. Wie nog beweert dat we ‘niet zo alarmistisch moeten doen over de opwarming ‘ is onethisch, De Morgen, December 24

IPBES [2019]. Nature’s Dangerous Decline ‘Unprecedented’; Species Extinction Rates‘Accelerating’, Media Release, pp. 9

IPCC [2019]. The Ocean and Cryosphere in a Changing Climate, Summary for Policymakers, pp. 45

Tollefson [2019]. Trump Administration Relaxes Emissions Limits on Power Plants, Scientific American, pp. 5