Immunoassay is recognized as a promising method for screening environm
ental contaminants. Numerous immunoassays have already been developed,
and especially the rapidity, sensitivity, and cost-effectiveness of t
his method are considered as advantageous for screening purposes to re
duce sample load for conventional analyses. A particular interesting a
pplication involves water quality control with regard to pesticides, f
or which in Europe a threshold concentration of 0.1 mu g/L applies. An
overview is given of the various pesticides for which immunoassays ha
ve been developed, including commercially available kits. Pros and con
s, applicability, and results of fields tests are discussed. Additiona
lly, a survey is given on further developments for improvement of exis
ting or new immunoassays and on the application of immunochemistry in
other embodiments (immunoaffinity chromatography, immunosensors). Part
icular emphasis is laid on validation and standardization of immunoass
ays.