Quantitative analysis of morphological damage (QuAMoDa): a tool for effects assessment

For evaluating the ecotoxicological risk of environmental chemicals there is the need for quantitative assessment of the effects, in order to produce concentration-effects relationships. Many tests for assessing histological damages often report results in qualitative terms. For covering the gap between these results and the requirement of risk assessment procedures, a quantitative method is necessary. The present study was designed to set up a methodological protocol for a Quantitative Analysis of Morphological Damage (QuAMoDa) that will serve as guidelines for scoring tissue or organ morphological alterations in organisms exposed to xenobiotics (i.e. environmental pollutants, drugs etc.). The performance of the procedure has been tested by examining in Xenopus laevis larvae (stage 47, 120 h post fertilization) a morphological alteration of tail skeletal muscle caused by exposure to the organophosphorothioate insecticide chlorpyrifos (CPF). Three sets of 60 longitudinal sections each, two exposed for 24 h and 120 h to CPF and one as a control were examined.