Aj. Morgan et al., A short overview of molecular biomarker strategies with particular regard to recent developments in earthworms, PEDOBIOLOG, 43(6), 1999, pp. 574-584
Biomarkers are increasingly used, especially in aquatic toxicology, as sub-
lethal. stress indicators for hazard assessment. The objective of the prese
nt overview was to seek some patterns in this rapidly expanding field so as
to facilitate progress toward a flexible framework within which earthworm
biomarkers can be deployed to maximal terrestrial ecotoxicological advantag
e. Three trends were evident. Trend I - the application of biomarkers seque
ntially as a hierarchial series : Tier I biomarkers responding indiscrimina
tely to general stress; Tier IT biomarkers responding to a family of(chemic
ally) related stressors; Tier III biomarkers responding discriminately to s
pecific stressors. Trend 2 - the linkage between levels, whereby limited ef
forts have been made to establish relationships that are (ideally) mechanis
tic rather than merely statistically correlative between low-organisational
-level (i.e. molecular and cellular) responses and higher level (i.e. life-
cycle parameters, population, community) alterations. Trend 3 - the derivat
ion of 'value added' information from biomarker arrays or suites analysed b
y multivariate techniques to yield more information than from biomarkers de
ployed and interpreted individually. Trend I is useful for rapid screening
of new agrochemicals, early warning of perturbations in habitats contaminat
ed, with single and multiple stressors, and to quickly assess recovery afte
r ameliorative or remediative interventions. Trend 2 is potentially useful
for predicting the long-term L ecological consequences of toxicant release
based on short-tr;nn biological effects. Trend 3 will increasingly be usefu
l in comprehensive, perhaps macro-scale, environmental diagnostics.