Vulnerable windows for developmental ethanol toxicity in the Japanese medaka fish (Oryzias latipes).

Ethanol (EtOH) is a well-known developmental toxicant that produces a range of abnormal phenotypes in mammalian systems including craniofacial abnormalities, cognitive deficits and growth retardation. While the toxic potential of developmental EtOH exposure is well characterized clinically, the effect of timing on the extent of toxicity remains unknown. Fish models such as the Japanese medaka, Oryzias latipes, provide a convenient system for investigating the effects of developmental EtOH exposure in vivo.

Adapting the medaka embryo assay to a high-throughput approach for developmental toxicity testing.

Chemical exposure during embryonic development may cause persistent effects, yet developmental toxicity data exist for very few chemicals. Current testing procedures are time consuming and costly, underlining the need for rapid and low cost screening strategies. While in vitro methods are useful for screening, these methods do not replicate all the intricacies of embryonic development and should ideally be complemented by an in vivo screening strategy.

Neurochemical effects of chronic dietary and repeated high-level acute exposure to chlorpyrifos in rats.

Very little is known about the effects of chronic exposure to relatively low levels of anticholinesterase insecticides or how the effects of chronic exposure compare to those of higher, intermittent exposure. To that end, adult male rats were fed an anticholinesterase insecticide, chlorpyrifos (CPF), for 1 year at three levels of dietary exposure: 0, 1, or 5 mg/kg/day (0+oil, 1+oil, and 5+oil). In addition, half of each of these groups also received a bolus dosage of CPF in corn oil ("spiked" animals; 60 mg/kg initially and 45 mg/kg thereafter) every 2 months (0+CPF, 1+CPF, 5+CPF).