2024-06-162024-06-162015https://doi.org/10.60810/openumwelt-2175https://openumwelt.de/handle/123456789/8236In its recent guidance document on tiered risk assessment for plant protection products for aquatic organisms, the EuropeanFood SafetyAuthority (EFSA) proposed to use Glyceriamaximaas monocotyledonous grass species for the testing of special herbicide groups. However, published toxicity data for this species is very limited and there is no test guideline for Glyceriasp. For this reason a microcosm study was conducted in order to gain experience on the degree of sensitivity of G.maximato the herbicidal substances clodinafop-propargyl (grass herbicide) and fluroxypyr (auxin) in comparison to the already established test organism water milfoil Myriophyllum spicatumand the duckweed species Landoltiapunctata. Five concentrations without replicates were tested for each test substance using 10 microcosms and three microcosms served as controls. The experiment was run for 8 weeks. Morphological endpoints were used to determine growth and EC50values. The results show that M. spicatumwas most sensitive to fluroxypyr (37 days EC50for roots: 62 ng/L) and G.maximamost sensitive to clodinafop-propargyl (22 days EC50for total shoot length: 48 ng/L) whereas the duckweed species was considerable less sensitive. Hence, G.maximaturns out to be a good candidate for testing grass specific herbicides, supporting its inclusion as an additional macrophyte test for the risk assessment of herbicides as proposed by the EFSA. Quelle: http://link.springer.comgerhttp://rightsstatements.org/vocab/InC/1.0/TausendblattToxizitätWissenschaftlicher Artikel