title: Tissue distribution, metabolism and hepatic tissue injury in Chinese lizards (Eremias argus) after a single oral administration of lambda-cyhalothrin.
abstract: Lambda-cyhalothrin (LCT) is a widely used pyrethroid with neurotoxicity. However, little is known about the toxicokinetics of LCT in reptiles. In this study, the absorption, distribution, metabolism and excretion of LCT in Chinese lizards (Eremias Argus) were determined following a single dose (10 mg kg-1) treatment. In the liver, brain, gonads and skin, LCT levels peaked within several hours and then decreased rapidly. However, the concentration of LCT gradually increased in the fat tissue. More than 90% of the LCT dose was excreted in the faeces. One LCT metabolite, 3-phenoxybenzoic acid (PBA), was detected in lizard plasma and tissues. PBA preferentially accumulates in the brain and plasma. The half-life of PBA in the brain was 3.2 days, which was 35.4-fold greater than that of LCT. In the plasma, the concentration of PBA was significantly higher than that of LCT. The bioaccumulation of LCT in tissues was enantioselective, and the enantiomeric fractions (EF) ranged from 0.72 to 0.26. The preferential accumulation of enantiomers changed according to exposure time, but the reasons behind this phenomenon were not clear. For pathological analysis, vacuolation of the cytoplasm and large areas of necrosis were observed in the liver sections after 168 h of dosing. The liver tissues exhibited both decreases in the hepatosomatic index and histopathological lesions during the exposure period. In this study, the effect concentration of LCT in lizards was 200-fold lower than its LD50value used in risk assessments for birds. These results may provide additional information for the risk assessment of LCT for reptiles and indicate that birds may not be an ideal surrogate for reptile toxicity evaluation.
authors: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China; University of Chinese Academy of Sciences, Yuquan RD 19 a, Beijing, 100049, China.
authors: Jing
authors: J
authors: Chang
authors: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China; University of Chinese Academy of Sciences, Yuquan RD 19 a, Beijing, 100049, China.
authors: Jitong
authors: J
authors: Li
authors: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China.
authors: Huili
authors: H
authors: Wang
authors: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China.
authors: Yinghuan
authors: Y
authors: Wang
authors: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China.
authors: Baoyuan
authors: B
authors: Guo
authors: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China; University of Chinese Academy of Sciences, Yuquan RD 19 a, Beijing, 100049, China.
authors: Jing
authors: J
authors: Yin
authors: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China; University of Chinese Academy of Sciences, Yuquan RD 19 a, Beijing, 100049, China.
authors: Weiyu
authors: W
authors: Hao
authors: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China.
authors: Wei
authors: W
authors: Li
authors: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China.
authors: Jianzhong
authors: J
authors: Li
authors: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China. Electronic address: pengxu@rcees.ac.cn.
authors: Peng
authors: P
authors: Xu
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000284:Administration, Oral; D000818:Animals; D001565:Benzoates / Q000378:metabolism / Q000493:pharmacokinetics*; D001717:Birds; D001921:Brain / Q000378:metabolism; D056486:Chemical and Drug Induced Liver Injury / Q000473:pathology*; D006207:Half-Life; D007306:Insecticides / Q000493:pharmacokinetics / Q000633:toxicity; D008099:Liver / Q000378:metabolism / Q000473:pathology*; D008116:Lizards / Q000097:blood / Q000378:metabolism*; D008297:Male; D009570:Nitriles / Q000493:pharmacokinetics* / Q000633:toxicity*; D011722:Pyrethrins / Q000493:pharmacokinetics* / Q000633:toxicity*; D012867:Skin / Q000378:metabolism; D013237:Stereoisomerism; D014018:Tissue Distribution
chemical_list: D001565:Benzoates; D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; C017618:3-phenoxybenzoic acid; C037304:cyhalothrin
keywords: Distribution; Histopathology; Lambda-cyhalothrin; Lizard; Metabolism