Emans HJB ,
Okkerman PC ,
Plassche EJ van de ,
Sparenburg PM ,
Canton JH
38 p
in Dutch
1992
Toon Nederlands
English Abstract For effects assessment several extrapolation methods
can be used to derive the concentration of toxic chemicals above which
adverse effects on terrestrial or aquatic ecosystems may occur. These
methods are based on single species toxicity data. At present, however, it
is uncertain whether the values calculated with these extrapolation methods
really represent accurate estimations of concentrations harmless to
ecosystems. Therefore a validation of extrapolation methods was carried out
by comparing No Observed Effect Concentrations derived from multiple species
(semi-) field experiments with extrapolated values. In this study
validation was restricted to the methods of Aldenberg & Slob (1991) and
Wagner & Lokke (1991) and a modification of the method of the United States
Environmental Protection Agency (OECD, 1991). Multiple species experiments
for organic compounds and metals in aquatic ecosystems were studied. For
only 29 compounds, 19 organic compounds and 10 metals, one or more multiple
species NOECs could be derived. For 11 of these compounds, an insufficient
number of single species toxicity data was available to apply the methods of
Aldenberg & Slob and Wagner & Lokke. With reservations, due to the paucity
of data, it is concluded that single species toxicity data can be used to
derive "safe" values for the aquatic ecosystem. Furthermore, extrapolation
methods seem to be a good basis for determining these values. Based on the
results of this study the best correlation between MS NOECs and extrapolated
values can be obtained with the methods of Aldenberg & Slob and Wagner &
Lokke, both with a 95& protection level and a 50% confidence
level.