Sammanfattning

Agricultural land-use frequently results in short pulse exposures of insecticides such as pyrethroids in river systems, adversely affecting local invertebrate communities. In order to assess insecticide-induced effects, stream mesocosms are used within higher tier aquatic risk assessment. Regulatory acceptable concentrations (RACs) derived from those studies are often higher compared with tier 1 RACs. Hence, the present mesocosm study evaluates this aspect using a pulse exposure scenario typical for streams and the pyrethroid insecticide etofenprox. A 6-h pulse exposure with measured concentrations of 0.04, 0.3 and 5.3 mu g L-1 etofenprox was used. We considered abundance, drift and emergence of invertebrates as structural endpoints and the in situ-measured feeding rates of the isopod Asellus aquaticus as functional endpoint. Most prominent effects were visible at 5.3 mu g L-1 etofenprox which caused adverse effects of up to 100% at the individual and population level, as well as community structure alterations. Transient effects were observed for invertebrate drift (effect duration <= 24 h) and for the invertebrate community (9 days after exposure) at 0.3 mu g L-1 etofenprox. Furthermore, 0.04 mu g L-1 etofenprox affected the abundance of the mayfly Cloeon simile (decrease by 66%) and the feeding rate of A. aquaticus (decrease by 44%). Thus, implications for the functional endpoint leaf litter breakdown in heterotrophic ecosystems may be expected. A hypothetical RAC derived from the present mesocosm study (0.004 mu g L-1) is in line with the official tier 1 RAC (0.0044 mu g L-1) and thus shows that the present mesocosm study did not result in a higher RAC. (C) 2017 Elsevier B.V. All rights reserved.

Nyckelord

Functional endpoint; Aquatic guidance document; Community; Drift; Emergence

Publicerad i

Science of the Total Environment
2018, Volym: 610-611, sidor: 810-819

SLU författare

• Bundschuh, Mirco

  • Institutionen för vatten och miljö, Sveriges lantbruksuniversitet
    

Associerade SLU-program

SLU Nätverk växtskydd


Globala målen

SDG6 Säkerställa tillgången till och en hållbar förvaltning av vatten och sanitet för alla


UKÄ forskningsämne

Övrig annan naturvetenskap


Publikationens identifierare

DOI: https://doi.org/10.1016/j.scitotenv.2017.08.048

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/86680