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While a number of studies have addressed bioaccumulation of the flame retardant Dechlorane Plus (DP), little information is available regarding the adverse effects of DP on animals, especially on bird species. In the present study, male common quails ( Coturnix coturnix) were consecutively exposed to commercial DP-25 by gavage for 90 d at 1-mg/kg/d, 10-mg/kg/d, and 100-mg/kg/d dosages. Concentrations of DP isomers in liver, muscle, and serum were determined after exposure. Liver enzyme activity involved in xenobiotic biotransformation processes and oxidative stress was measured, as well as glutathione and maleic dialdehyde content. The results showed that DP was more prone to accumulate in the liver than in muscle and serum in all exposed groups. In tested tissues, syn-DP dominated in the high-exposure groups (10 and 100 mg/kg/d), whereas anti-DP tended to accumulate in the low-exposure group (1 mg/kg/d). The concentration ratios of anti-DP to total DP ( f anti values) in the tissues examined were close to commercial DP in the low-exposure group; however, the f anti values were significantly decreased in the high-exposure groups. Enzyme activity of 7-pentoxyresorufin-O-demethylase (PROD) decreased significantly in all exposed groups compared with the control group, whereas activity of erythromycin N-demethylase (ERND) and the antioxidant enzyme catalase significantly increased in high-exposure groups. The results implied that DP exposure levels influenced isomeric compositions in organs and that DP exposure altered hepatic alkoxyresorufin O-dealkylase (AROD) activity and contributed to the biological effects of DP. Environ Toxicol Chem 2013;32:1649-1654. © 2013 SETAC [ABSTRACT FROM AUTHOR]

Chlorpyriphos (13 mg/kg) was administered to quail (Coturnix coturnix), and the responses of brain acetylcholinesterase (AChE) and plasmacholinesterase (ChE) were studied. Both enzymes responded rapidly, and the maximal inhibition (76.6 and 80.1%, respectively) occurred 8 hpostadministration. Plasma ChE recovered rapidly, and even on day 4,ChE values of quail that had received chlorpyriphos were higher thanthose of controls. The recovery of brain AChE activity was slower than that of plasma; it reached 59% of controls 2 d after chlorpyriphosadministration, then it recovered slowly, and only at day 11 was itslevel not depressed with respect to controls. This recovery followedthe logarithmic pattern Y= a + b(log X), where Y is the AChE activity expressed as the percentage with respect to controls and X is the day after closing, giving a significant correlation (r = 0.9746, p< 0.001 when using group means and r = 0.9219, p < 0.001 when using individual values). No clinical signs or mortality were observed, and histopathological observations in the central nervous system (encephalytic reaction, necrotic Purkinje cells), liver (congestion, vacuolation), and kidney (congestion, nephrosis) were not severe and did not endanger the life of the quail. Sixteen hours after chlorpyriphos administration, some quail were treated with pralidoxime, which significantly reactivated brain AChE but not plasma ChE. However, this effect didnot last for the rest of the experiment; because no signs of toxicosis appeared, the experiment was not repeated. [ABSTRACT FROM AUTHOR]