Chronic Toxicity of Chloroform to Japanese Medaka Fish

Abstract

Materials and Methods Test materials. Chloroform (CAS No. 67-66-3) of 99.8% purity was obtained from Aldrich Chemical Company (Milwaukee, WI). Weekly chemical analyses of aquaria water demonstrated that chloroform did not break down to form other compounds. Under the continuous flow-through dosing regimen, sufficient chloroform remained in solution during testing to maintain dosage levels. Approximately 10 L of 100 mg/L chloroform stock were prepared each day. Processed well water was the diluent used. The chloroform stocks were stirred for 24 ± 2 hr in a sealed glass container, and then pumped into a diluter dosing bottle. BrdU (CAS No. 59-14-3) of 99% purity was obtained from Sigma Chemical Co. (St. Louis, MO). BrdU is water soluble, not volatile, and stable under test conditions. A stock solution of 10 g/L BrdU was prepared in ASTM Type I water on the day of exposure. Animal care. Research was conducted in compliance with the Animal Welfare Act and other federal statutes and regulations relating to animals and experiments involving animals, and adheres to principles stated in the Guide for the Care and Use of Laboratory Animals (27). The facilities are fully accredited by the Association for the Assessment and Accreditation of Laboratory Animal Care, International. Japanese medaka fish (Oryzias latipes) were supplied from the U.S. Army Center for Environmental Health Research (USACEHR) in-house cultures and were reared according to USACEHR standing operating procedures. Fish were fed flake food (Aquatox Certified Diet, Ziegler Brothers, Gardners, PA) and live 24-hr brine shrimp daily. Fish were fasted 24 hr before the 6-and 9-month histopathology sacrifices

Evidence of Bioactivation of Halomethanes and its Relation to Oxidative Stress Response in Chirostoma riojai, an Endangered Fish from a Polluted Lake in Mexico

“…Darnerud et al (1989) showed the presence of nonvolatile metabolites of carbon-14-labeled 1,2-dibromoethane and CHCl 3 mainly in liver and kidney of rainbow trout and, to lesser extent, in gill and intestinal mucosa. The hepatic bioaccumulation of BrCHCl 2 occurring with chronic exposure in medaka (Oryzias latipes) was dependent on body levels (Toussaint et al 2001a), but apparently CHCl 3 is not bioaccumulated in liver (Toussaint et al 2001b). Both previous and present results suggest that HM metabolism depends on the species involved as well as on patterns of chlorination (Birge and Cassidy 1983) and body levels (Hendriks 1995).…”

“…Dependency of the patterns of HM halogenation on sex-linked response may nevertheless exist. Chronic exposure to CHCl 3 induced biliary carcinogenesis in female medaka, but early hepatocellular necrosis and concomitant compensatory hyperplasia did not occur (Toussaint et al 2001b). Although a histopathological study of C. riojai was not made, the greater HSI values obtained in summer may be associated with canalicular cholestasis and hyperplasias.…”

Growth and Haematological Changes in African Catfish Clarias gariepinus Juveniles Exposed to Mercuric Chloride

“…The exposure of Oreochromis niloticus Thiobencarp herbicide for 8 weeks revealed that, fish showed a reduction in body weight gain compared to the control group parameters such as specific growth rate (SGR), food conversion efficiency (FCE), protein efficiency ratio (PER), food conversion rate (FCR) decreased with increased concentration of mercuric chloride. Decrease growth rate as observed by Toussain et al [32] and Onusiriuka, [33] that exposed Japanese Medaka fish and…”

Exposure to the synthetic FXR agonist GW4064 causes alterations in gene expression and sublethal hepatotoxicity in eleutheroembryo medaka (Oryzias latipes)

“…Studies from this and other laboratories have shown that hepatocytes and biliary epithelial cells are sensitive responders under conditions of acute and chronic toxicity in medaka (Toussaint et al, 2001a, 2001b; Wolf and Wolfe 2005; Hardman et al, 2008; Volz et al, 2008). The role of BPDECs in the hepatobiliary toxicity after exposure to GW4064 required use of a tiered histopathological approach.…”