John Wiley & Sons, Ltd.

Current‐use pesticides in stream water and suspended particles following runoff: Exposure, effects, and mitigation requirements

0
The EU‐Directive for sustainable use of pesticides requires implementation of risk mitigation measures at streams which are threatened by pesticide entries. The need for mitigation measures was investigated at 10 stream sites within an intensively used arable region in central Germany by characterising pesticide exposure following edge‐of‐field runoff and effects on the aquatic macroinvertebrates. Moreover, the influence of riparian buffer strip width (as a mitigation measure) at the sampling sites was considered. Generally, invertebrate fauna was dominated by pesticide‐tolerant species, suggesting a high pesticide exposure at almost all sites. This result is also reflected by the elevated levels of suspended particle contamination in terms of toxic units (logTUMax > ‐2), corresponding to 1/100 of the acute lethal concentration (LC50) to Daphnia magna. At two sites that received high aqueous‐phase entries of the pyrethroid lambda‐cyhalothrin (logTUMax > ‐0.6), the abundance and number of sensitive species in terms of the SPEAR index decreased during the pesticide application period. In contrast, no acute significant negative effects on macroinvertebrates were observed at sites characterised by low water‐phase toxicity (logTUMax < ‐3.5). An influence of riparian buffer strip width on pesticide exposure was not observed, supposedly because of the presence of erosion rills and ephemeral ditches. In conclusion, results show that mitigation measures (such as the improvement of currently present riparian buffer strips) are needed in the study area. Environ. Toxicol. Chem. © 2013 SETAC

Customer comments

No comments were found for Current‐use pesticides in stream water and suspended particles following runoff: Exposure, effects, and mitigation requirements. Be the first to comment!