title: Prosobranch snails as test organisms for the assessment of endocrine active chemicals--an overview and a guideline proposal for a reproduction test with the freshwater mudsnail Potamopyrgus antipodarum.
abstract: Recently, prosobranch snails have been recommended as promising candidates for test organisms for the assessment of endocrine active chemicals. Three prosobranch snail species, the freshwater mudsnail Potamopyrgus antipodarum, the freshwater ramshorn snail Marisa cornuarietis, and the marine netted whelk Nassarius reticulatus are portrayed and their respective biotests are presented together with results of laboratory experiments and biological effect monitoring surveys in the field. All characterized species are highly sensitive toward xeno-androgens [triphenyltin (TPT), tributyltin (TBT), methyltestosterone (MT) and fenarimol (FEN)], and xeno-estrogens [bisphenol A (BPA), octylphenol (OP), ethinylestradiol], and show effects at environmentally relevant, rather low concentrations in laboratory experiments. For exposure to the xeno-androgen TPT, EC(10) values range between 15.9 and 29.0 ng as Sn/L (sediment 0.03 mug as Sn/kg), for TBT, EC(10) values are found between 3.42 and 37.8 ng as Sn/L (sediment 2.98 microg as Sn/kg) and effect concentrations for FEN are calculated as 18.6 ng/L (EC(10)) and 0.19 microg/kg (EC(50) sediment; EC(10) not calculable). Exposure to xeno-estrogens yielded EC(10 )values of 13.9 ng/L (0.19 microg/kg) for BPA, a NOEC of <1 microg/L (EC(10) of 0.004 microg/kg) for OP and a NOEC of 1 ng/l (EC(10) sediment of 2.2 microg/kg) for ethinylestradiol. Responses to androgens comprised the development of imposex and the reduction of fertility or embryo production, effects of estrogens included the stimulation of egg production and embryo production, and the increased weight of glands. Also, biological effect monitoring studies with P. antipodarum and N. reticulatus in several rivers or estuarine areas revealed the capacity of the biotests to detect an androgenic or estrogenic potential of sediment samples. A comparison of the three test species with regard to sensitivity and practical aspects in routine application favors the freshwater mudsnail P. antipodarum for a standardized procedure, and this reproduction test will be introduced into the OECD guideline program for standardization in the near future.
authors.affiliation: Department of Ecology and Evolution--Ecotoxicology, J W Goethe University Frankfurt, Siesmayerstrasse 70, D-60054 Frankfurt am Main, Germany. m.duft@bio.uni-frankfurt.de
authors.forename: Martina
authors.initials: M
authors.lastname: Duft
authors.forename: Claudia
authors.initials: C
authors.lastname: Schmitt
authors.forename: Jean
authors.initials: J
authors.lastname: Bachmann
authors.forename: Cornelius
authors.initials: C
authors.lastname: Brandelik
authors.forename: Ulrike
authors.initials: U
authors.lastname: Schulte-Oehlmann
authors.forename: Jörg
authors.initials: J
authors.lastname: Oehlmann
mesh_terms: D000818:Animals; D052244:Endocrine Disruptors / Q000633:toxicity*; D017408:Guidelines as Topic; D023421:Models, Animal; D012098:Reproduction / Q000187:drug effects; D012908:Snails / Q000187:drug effects* / Q000502:physiology; D018675:Toxicity Tests / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000633:toxicity; D015262:Xenobiotics / Q000633:toxicity
chemical_list: D052244:Endocrine Disruptors; D014874:Water Pollutants, Chemical; D015262:Xenobiotics