An Example of Effect Biomonitoring

In the following section, an example of effect monitoring that fulfils the requirements of Sections 12.4.2 to 12.4.4, where precision, calibration, and harmonization will be discussed in the use of snails to monitor bisphenol A (BPA). The more detailed experimental features of this investigation may be found elsewhere (Schulte-Oehl-mann et al. 2001). 

Within a federal Environmental Agency research project to develop a biological test for hormone-mimetic compounds using the freshwater snail Marisa comuarietis, the effects of the suspected xenoestrogenic substance BPA, not only on freshwater but also on marine prosobranch snails, were investigated (Schulte-Oehlmann et al. 2001). 

For the laboratory experiments the rams-horn snail M. comuarietis and the ovovivipar-ous snail Potamopyrgus antipodarum were considered as freshwater species, and two marine prosobranchs - the netted whelk Nassarius reticulatus and the dog whelk Nucella lapillus - were additionally employed. N. reticulatus, as a typical sediment-living species, was exposed via artificial sediments, while the three other prosobranchs were exposed via water. 

The test series with M. comuarietis covered a nominal concentration range between 1 

3 ng a No Observed Effect Concentration (NOEC) of 7.9ng and an Effective Concentration 10 (ECm) of 13.9 ng were calculated. Super females occurred also in the BPA exposure experiment with the other snail species, but comparable oviduct malformations as in Marisa were not found, probably due to species differences in the gross anatomical structure of the pallial oviduct. 

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