Wageningen University & Research is investigating the crop-protection products produced by manufacturers and the ecotoxicological effects of fungicides in sediments in waterways. This TKI Delta Technology project is part of the Sustainable Water Management programme.
Reason for the project
In a recently published scientific opinion from the European Food Safety Authority (EFSA), proposals are made for evaluating the environmental risks of pesticides accumulating in sediment, with the aim of protecting benthic organisms in freshwater ecosystems. These proposals are most likely to be applied in the near future within the scope of the crop protection-product authorisation policy. However, the decision trees proposed by EFSA are yet to be accredited and require new research data, since the toxicological data for benthic organisms is limited, particularly for fungicides accumulating in the sediment. Both for the authorities – European and national – and for the chemical industry it is important to gain an understanding of whether the proposed decision trees for assessing effects on sediment-dwelling organisms are over- or under-protective.
Aim of the project
- Conducting a semi-field experiment in microcosms with sediment spiked with the fungicide Fludioxonil (benchmark compound) with the aim of determining a concentration-response relationship for benthic organisms (population and community).
- Performing sediment-spike laboratory toxicity tests with standard and additional benthic organisms to evaluate the first stage (standard test species approach) and the second stage (Species Sensitivity Distribution approach) effect assessment by comparing the results with those of the semi-field experiment.
Description of the activities
- Summer 2016: Conducting semi-field experiment on the Sinderhoeve (Renkum);
- Autumn 2016: Conducting sediment toxicity tests with standard test organisms proposed by EFSA (Chironomus riparius, Hylalella azteca, Lumbriculus variegatus);
- First half of 2017; Conducting additional toxicity tests with benthic organisms – such as benthic nematodes, oligochaete worms, snails and arthropods – and elaborating results of the semi-field experiment.
- Second half of 2017: Writing scientific publications.
Data that can be used to calibrate/validate the EFSA methodology for assessing the effect of pesticides on sediment-dwelling aquatic organisms. Critically evaluating the productive value of the proposed EFSA methodology for effect assessment in authorising crop protection products. Data and scientific publications made available to all stakeholders with interest in the authorisation of crop protection agents such as government, agricultural companies and the chemical industry. Suggestions for an efficient and cost-effective assessment of the effect of exposure to pesticides for sediment-dwelling organisms based on the EFSA proposals.
State-of-the-art knowledge relating to the ecotoxicology risk assessment can be found in the following scientific publications:
- Deneer JW, Arts GHP, Brock TCM (2013). Sediment toxicity data for benthic organisms and plant protection products. Alterra report 2485, ISSN 1566-7197, Wageningen, 48 pp.;
- Diepens NJ, Koelmans AA, Baveco H, van den Brink PJ, van den Heuvel-Greve MJ, Brock TCM (2016). Prospective environmental risk assessment for sediment-bound organic chemicals: A proposal for tiered effect assessment. Reviews of Environmental Contamination and Toxicology DOI 10.1007/398_2015_5004;
- EFSA PPR (2015). Scientific Opinion on the effect assessment for pesticides on sediment organisms in edge-of-field surface water. EFSA Journal 2015;13(7):4176, 145 pp. doi :10.2903/j.efsa.2015.4176.
These reports demonstrate that the knowledge relating to the ecotoxicology of benthic organisms and crop protection products accumulating in sediment are indeed limited. However, government requires that a thorough risk assessment for sediment-dwelling organisms is conducted while the chemical industry wants the assessment methods to be sufficiently validated and cost-effective.
The partners within the consortium hope that the results of the project – which are made available as open domain publications – will be used by EFSA and authorisation bodies for further developing an efficient and cost-effective assessment in authorising crop-protection products and that these insights will be translated into Guidance Documents.