title: Sensitivity of Costa Rica's native cladoceran Daphnia ambigua and Simocephalus serrulatus to the organophosphate pesticide ethoprophos.
abstract: The study of pesticide toxicity in aquatic environments is assessed with ecotoxicological tests and most research has been performed using species from temperate regions. In the present study, series of acute (48 hrs) toxicity tests to compare the sensibility of two indigenous cladocera of Costa Rica and two reference species were used in temperate regions to the organophosphate pesticide, Ethoprophos. Additionally, reproduction tests using S. serrulatus with sub lethal concentrations of ethoprophos and a control were assayed to check its sensitivity over a longer period exposure. The sensitivity of Costa Rica's native species Daphnia ambigua (EC50 48 hr: 12.9 +/- 3.0 microg(l(-1)) and Simocephalus serrulatus (10.6 +/- 2.1 microg l(-1)) to ethoprophos were higher (p < 0.05) when compared to the exotic species Daphnia magna (289.8 +/- 77.4 microg l(-1)), and were comparable to that of the more widely distributed species, Ceriodaphnia dubia (18.2 +/- 5.2 microg l(-1)). No effect on S. serrulatus reproduction was observed at concentrations between 1 and 4 microg l(-1). This study provides information that can be considered in the selection of species for ecosystem studies of pesticide toxicity in neotropical regions.
authors.affiliation: Instituto Regional de Estudios en Sustancias Tóxicas (IRET), Universidad Nacional de Costa Rica, Heredia 86-3000, Costa Rica. maria.arias.andres@una.cr
authors.forename: María
authors.initials: M
authors.lastname: Arias-Andrés
authors.affiliation: Instituto Regional de Estudios en Sustancias Tóxicas (IRET), Universidad Nacional de Costa Rica, Heredia 86-3000, Costa Rica.
authors.forename: Freylan Mena
authors.initials: FM
authors.lastname: Torres
authors.affiliation: Instituto Regional de Estudios en Sustancias Tóxicas (IRET), Universidad Nacional de Costa Rica, Heredia 86-3000, Costa Rica.
authors.forename: Seiling
authors.initials: S
authors.lastname: Vargas
authors.affiliation: Instituto Regional de Estudios en Sustancias Tóxicas (IRET), Universidad Nacional de Costa Rica, Heredia 86-3000, Costa Rica.
authors.forename: Karla
authors.initials: K
authors.lastname: Solano
mesh_terms: D000818:Animals; D003621:Daphnia; D063086:Organothiophosphates; D009946:Organothiophosphorus Compounds / Q000633:toxicity*; D010575:Pesticides / Q000633:toxicity*; D023382:Toxicity Tests, Acute; D036401:Toxicity Tests, Chronic
chemical_list: D063086:Organothiophosphates; D009946:Organothiophosphorus Compounds; D010575:Pesticides; C001182:ethoprop