title: Dominant lethal effects of 2,4-D in Biomphalaria glabrata.
abstract: Dominant lethal effects of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) were evaluated in the freshwater snail Biomphalaria glabrata. Wild-type snails were exposed during 10 days to 50, 75 and 100ppm of 2,4-D dimethylamine salt (2,4-D DMA) and paired with non-exposed albino snails 1, 11, 25 and 40 days after the exposure. The offspring of the non-exposed albino snails was scored for lethal malformations. One day after the exposure, a significant effect was observed at 75 and 100ppm without a dose-response relationship. After 11 days, the effect was observed only at the highest dose. After 25 days, significant increases in the dominant lethal effects occurred at 50 and 75ppm; effects were directly related to the doses. Background levels of lethal malformations were resumed after 40 days. Although the major and direct measure of dominant lethal mutations is the rate of lethal malformations in the heterozygous offspring of the albino snails, the sensitivity of the assay was substantially increased with the evaluation of all non-viable embryos, that are the sum of those with lethal malformations, identified or not as wild-type.
authors.affiliation: Instituto Butantan, Laboratorio de Parasitologia, Avenida Vital Brasil, 1500, 05503-900 Sao Paulo, Brazil. eliananakano@butantan.gov.br
authors.forename: Ethiene Castellucci
authors.initials: EC
authors.lastname: Estevam
authors.forename: Eliana
authors.initials: E
authors.lastname: Nakano
authors.forename: Toshie
authors.initials: T
authors.lastname: Kawano
authors.forename: Carlos Alberto
authors.initials: CA
authors.lastname: de Bragança Pereira
authors.forename: Francisco Fernandes
authors.initials: FF
authors.lastname: Amancio
authors.forename: Ana Maria Mendonça
authors.initials: AM
authors.lastname: de Albuquerque Melo
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000633:toxicity*; D000818:Animals; D001700:Biomphalaria / Q000187:drug effects* / Q000196:embryology / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D004625:Embryo, Nonmammalian / Q000002:abnormalities / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005799:Genes, Dominant / Q000235:genetics; D005804:Genes, Lethal / Q000235:genetics; D005854:Germ Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D006540:Herbicides / Q000633:toxicity; D008297:Male; D009152:Mutagenicity Tests / Q000379:methods; D009153:Mutagens / Q000633:toxicity; D013997:Time Factors
chemical_list: D006540:Herbicides; D009153:Mutagens; D015084:2,4-Dichlorophenoxyacetic Acid