Biochemical effects of chlorpyrifos on two developmental stages of Xenopus laevis.
Environ Toxicol Chem
; 21(9): 1826-35, 2002 Sep.
Article
em En
| MEDLINE
| ID: mdl-12206422
ABSTRACT
Abstract-The effects of a 96-h static exposure to chlorpyrifos were examined in two developmental stages of larval Xenopus laevis (premetamorph and metamorph). Measures of effect included mortality, deformity, cholinesterase (ChE) activity, and DNA and protein concentration. All parameters indicated that metamorphs were more sensitive than were premetamorphs. For larvae exposed as premetamorphs, the median lethal concentration and median effective concentration were 14.6 mg/L and 1.71 mg/L; for those exposed as metamorphs, values were 0.56 mg/L and 0.24 mg/L, respectively. Cholinesterase activity was the most sensitive biochemical parameter. Exposure to chlorpyrifos at 0.01 mg/L caused significant decreases in the ChE activity of metamorphs; 0.1 mg/L significantly decreased premetamorph ChE activity. Metamorph DNA was significantly decreased at 0.1 mg/L; premetamorph DNA was not reduced until exposure to 1.0 mg/L. Whole-body protein was the least sensitive biochemical measure of effect. Premetamorphs did not experience a reduction in protein concentrations. Metamorph protein concentration was significantly decreased at 1.0 mg/L. Based on current surface water data, the most sensitive effect would not have a high probability (< or = 4.2%) of occurring in the environment.
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Base de dados:
MEDLINE
Assunto principal:
Anormalidades Congênitas
/
Poluentes Químicos da Água
/
Clorpirifos
/
Inseticidas
/
Metamorfose Biológica
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2002
Tipo de documento:
Article