18 December 2020 - Trouw: Interview Professor Annemarie van Wezel

From the North Pole to Mount Everest, chemicals can be found everywhere. “Thanks to our sensitive measuring methods, we always measure something, even if it is very little, you come across those substances everywhere because we use them all,” says Annemarie van Wezel, professor of environmental ecology and director of the Institute for Biodiversity and Ecosystem Dynamics ( IBED) from the University of Amsterdam. "We would love to go back to Adam and Eve, but we can't." Yet she is hopeful. A turnaround is feasible, although this will not be easy.

“Chemicals have brought us a lot, in agriculture, fire safety and the shelf life of materials and food. Ultimately, we must move towards less dependence and better restriction to essential use. But you have to look at that as a whole, not per substance. Because if you prohibit one substance, another that looks a lot like it, will replace it. ”

That makes it so difficult to prevent the spread of toxins, explains Van Wezel. “Compared to biocides, which are now widely used because of the corona pandemic, pesticides are receiving a lot of attention. Upon approval, we assess one product, which may be used in one crop. The problem is that the same substance can also be used in a different crop, end up in a different place or be used in a completely different context. But we don't look at that.”

Violette Geissen's SPRINT project may be able to change the European standards for the approval of chemical substances, Van Wezel thinks. For the authorization of one substance, the accumulation effect of several chemical substances is not considered. Geissen is looking at that cocktail effect. Furthermore, now it is not examined whether a substance is necessary, only what it does.


“There is no consideration of a possible non-chemical alternative,” explains Van Wezel. “Except for candidates for substitution, these are substances that we would prefer to ban but for which there are no alternatives yet. This applies, for example, to substances that remain in the environment for a long time, accumulate in the food chain or are easily soluble in water and can therefore pose a threat to drinking water. If there are insufficient alternatives, there is also a risk of resistance. Ultimately, the total volume of use is also very important. You see this for example with glyphosate, which is in many weed killers. It is not very toxic in itself, but it is widely used. ”

One substance, one assessment
European countries are trying to remove substances that are carcinogenic or endocrine disrupting or mutagenic. "Nearly 750 substances such as pesticides or biocides are now banned, but some of them will still be placed on the market through a different authorization framework." That is why Van Wezel advocates a general admission test for all applications. In an article in the scientific journal Journal Environmental Management, one of her colleagues, Joanke van Dijk, compares the authorization frameworks for medicines, veterinary medicines, pesticides, biocides and industrial use in relation to the Green Deal of European Commissioner Frans Timmermans. Main conclusion: one substance, one assessment. And then as green as possible, so biodegradable or in a closed circuit.

“It helps to filter the very bad substances and avoid use where possible,” says Van Wezel. And yet that does not always make sense. Producers regularly challenge the assessment by the Ctgb, "and we do not always win that because we cannot go further than the regulations allow". Users also often request an exemption from an unauthorized substance, out of agricultural necessity or for public health reasons. The latter happened, for example, when combating the tiger mosquito. "We advise on this, but the minister decides."

“We want to move towards a non-toxic environment. Then as a consumer you also need to know how dependent you are on those substances, what role they play in our daily life, our hygiene, and in pest prevention. Washing your hands with soap also destroys the virus, so you don't need any chemicals. ”


Soap is a nice toxic free alternative for chemicals. Beeld Colourbox


Read the full article here (Dutch)