By Natasha Foote
The European Food Safety Authority (EFSA) has published the results of its two pilot assessments on the risks posed to humans by residues of multiple pesticides in food, but an EU association advocating for a reduction of pesticides has deemed them “unfit for purpose.”
The assessments – one considering chronic effects on the thyroid system and the other acute effects on the nervous system – are the culmination of a multi-year collaboration between EFSA and the Dutch National Institute for Public Health and the Environment (RIVM).
The overall conclusion for both assessments is that consumer risk from dietary cumulative exposure is, with varying degrees of certainty, below the threshold that triggers regulatory action for all the population groups covered.
The documents were finalised following a two-month consultation period during which EFSA received valuable feedback from a variety of stakeholders, including national institutions, academia, non-governmental organisations and commercial associations, which included meetings held to help clarify the methodology and explain the results of the work.
The substances considered in the assessments were identified by EFSA’s pesticide experts using a methodology specially devised for classifying pesticides into “cumulative assessment groups”.
EFSA developed this methodology for pesticides in 2013 as a new approach for grouping pesticides. It paves the way for the implementation of cumulative risk assessment to assess the risk posed by exposure to multiple pesticide residues, as many fruit and vegetables are exposed to more than one kind of pesticide.
According to EFSA’s latest report, more than 65% of common fruits like table grapes, strawberries, cherries and pears, contain two or more pesticide residues.
EU regulation on maximum levels of pesticides in food (MRLs) stipulates that decisions on MRLs should take into account cumulative effects of pesticides as and when the methods to assess such effects become available.
In addition, the regulation covering the placing of pesticides on the market stipulates that pesticides should have no harmful effects – including cumulative effects – on humans.
However, Pesticide Action Network Europe (PAN), a group of more than 600 NGOs, said that the studies presented by EFSA seemed “unfit for purpose,” that is, to ensure that pesticides mixtures cause “no impact to human health and particularly to the most vulnerable groups in the population.”
PAN criticised the studies for being “completely hypothetical,” saying that no experimental studies using pesticide mixtures took place at any step of the assessment.
They added that, when examined in detail, they raise “major concerns on their adequacy to objectively and independently assess the toxicity of pesticide mixtures.”
PAN’s environmental toxicologist, Dr Angeliki Lyssimachou, said that “the most sensitive tests, which examine endocrine-related diseases following low-dose, continuous exposures, during sensitive or vulnerable periods of life-time have not been taken into account”.
“In a time where reducing pesticide dependency is a political priority, regulators have to stop pretending that pesticide cocktails are safe.”
“An additional safety factor for mixtures must urgently be placed in the pesticide safety assessment, which will inevitably reduce what levels of pesticide residues in food are considered safe,” she stressed.
Asked by EURACTIV about the choice not to include experimental studies, a spokesperson for EFSA said that experimental in vivo testing on vertebrate animals with pesticide mixtures “cannot be envisaged in view of the animal sufferings and the infinite number of combinations of individual compounds within a dietary mixture.”
They added that EFSA supports risk assessment approaches which “minimise and refine the use of experimental animals (in-vivo testing) and that promote the use of data derived from alternative approaches, where possible.”
“The methodology used to evaluate the combined toxicological effects of pesticides on the nervous system and the thyroid were based on existing scientific work in the area of mixture toxicology.”
“Alternative in vitro testing methods are under development, as part the Euromix project, for example,” the EFSA spokesperson added.
The spokesperson also said that the fact that some tests were left out was “explicitly recognised in the EFSA outputs,” specifying that some effects, in particular thyroid-mediated developmental neurotoxicity, “could not be considered because of lack of data.”
They added that EFSA recommends producing this kind of data, but limited its conclusions to the effects which were actually addressed in the published reports.
Assessments covering the effects of pesticides on other organs and body functions are due to follow in the coming years and EFSA is currently defining a comprehensive implementation plan with the European Commission.