Sampling and in situ exposure of Neomysis integer in the Westerschelde estuary for use with the selected biomarkers, will show if effects of exposure to endocrine disrupting chemicals are present in the field. Chemical analyses of the body burden of the sampled species will establish concentration-response relationships between a possible response of the selected biomarkers and the chemicals in question. This field study will provide an evaluation of the utility of the selected biomarkers for screening of endocrine disrupting effects in N. integer.