Passive dosing of triclosan in multigeneration tests with copepods - stable exposure concentrations and effects at the low µg/L range.
Environ Toxicol Chem
; 36(5): 1254-1260, 2017 05.
Article
em En
| MEDLINE
| ID: mdl-27731510
ABSTRACT
Ecotoxicity testing is a crucial component of chemical risk assessment. Still, due to methodological difficulties related to controlling exposure concentrations over time, data on long-term effects of organic chemicals at low concentrations are limited. The aim of the present study was, therefore, to test the applicability of passive dosing to maintain stable concentrations of the organochlorine bacteriocide triclosan in the water phase during a 6-wk multigeneration population development test with the harpacticoid copepod Nitocra spinipes. Triclosan was loaded into silicone (1000 mg), which was used as passive dosing phase in the exposure vials. The distribution ratio for triclosan between silicone and water (Dsilicone-water ) was 10466 ± 1927. A population development test was conducted at 3 concentration levels of triclosan that were measured to be 3 µg/L to 5 µg/L, 7 µg/L to 11 µg/L and 16 µg/L to 26 µg/L. The results demonstrate that passive dosing is applicable for long-term ecotoxicity testing of organic chemicals, including during significant growth of the test organism population. Shifts in the demographic structure of the population during exposure suggest the most severe effects were exerted on juvenile development. Progressively lower development index values in the populations exposed to increasing triclosan concentrations suggest developmental retardation. The results further stress the need for chronic exposure during ecotoxicity testing in chemical risk assessment because even the most sensitive endpoint was not significant until after 7 d of exposure. Environ Toxicol Chem 2017;361254-1260. © 2016 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Contexto em Saúde:
2_ODS3
Base de dados:
MEDLINE
Assunto principal:
Triclosan
/
Poluentes Químicos da Água
/
Copépodes
/
Anti-Infecciosos Locais
Tipo de estudo:
Risk_factors_studies
Limite:
Animals
Idioma:
En
Revista:
Environ Toxicol Chem
Ano de publicação:
2017
Tipo de documento:
Article