Premium
Mode of action and aquatic exposure thresholds of no concern
Author(s) -
de Wolf Watze,
SiebelSauer Angela,
Lecloux Andre,
Koch Volker,
Holt Martin,
Feijtel Tom,
Comber Mike,
Boeije Geert
Publication year - 2005
Publication title -
environmental toxicology and chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.1
H-Index - 171
eISSN - 1552-8618
pISSN - 0730-7268
DOI - 10.1897/04-133r.1
Subject(s) - risk assessment , percentile , environmental science , toxicology , environmental toxicology , aquatic toxicology , hazard , hazard analysis , ecotoxicology , mode of action , environmental chemistry , statistics , toxicity , computer science , mathematics , biology , ecology , chemistry , engineering , computer security , organic chemistry , aerospace engineering
Threshold concepts of toxicological concern are based on the possibility of establishing an exposure threshold value for chemicals below which no significant risk is to be expected. The objective of the present study is to address environmental thresholds of no toxicological concern for freshwater systems (ETNC aq ) for organic chemicals. We analyzed environmental toxicological databases (acute and chronic endpoints) and substance hazard assessments. Lowest numbers and 95th‐percentile values were derived using data stratification based on mode of action (MOA; 1 = inert chemicals; 2 = less inert chemicals; 3 = reactive chemicals; 4 = specifically acting chemicals). The ETNC aq values were derived by multiplying the lowest 95th percentile values with appropriate application factors; ETNC aq,MOA1–3 is approximately 0.1 μg/L. A preliminary analysis with complete MOA stratification of the databases shows that in the case of MOA1 or MOA2, the ETNC aq value could be even higher than 0.1 μg/L. A significantly lower ETNC aqMOA4 value was observed based on the long‐term toxicity information in the European Centre for the Ecotoxicology and Toxicology of Chemicals database. Application of the ETNC aq value in a tiered risk‐assessment scheme may help chemical producers to set data‐generation priorities and to refine or reduce animal use. It also may help to inform downstream users concerning the relative risk associated with their specific uses and be of value in putting environmental monitoring data into a risk‐assessment perspective.