title: The effect of subchronic metribuzin exposure to signal crayfish (Pacifastacus leniusculus Dana 1852).
abstract: OBJECTIVE
  The aim of the study was to investigate effects of the triazine herbicide metribuzin on signal crayfish Pacifastacus leniusculus Dana by determining oxidative stress (thiobarbituric acid reactive substances) and antioxidant indices (total superoxide dismutase, catalase, glutathione reductase) in hepatopancreas, muscle, and gill as well as assessing their histopathology.
  
  
  METHODS
  Crayfish were exposed to metribuzin concentrations of 0.52 μg x l(-1) (realistic environmental concentration) and 3.06 mg x l(-1) (10% 96hLC50) for 10 and 30 days followed by a 30-day depuration period without exposure to metribuzin.
  
  
  RESULTS
  In the thiobarbituric acid reactive substances, superoxide dismutase, and catalase were observed differences in all examined tissues compared to the control group. Differences from control were observed in glutathione reductase activity in hepatopancreas after 10 days for both exposure concentrations and after 30 days at 3.06 mg x l(-1). Histological examination revealed extensive focal autolytic disintegration of tubular epithelium in hepatopancreas of crayfish exposed to metribuzin for 30 days.
  
  
  CONCLUSIONS
  Chronic exposure of metribuzin resulted in oxidative damage to cell lipids, in changes of antioxidant activity in crayfish tissue, and pathological changes in hepatopancreas. The results suggest that selected oxidative stress biomarkers, antioxidant enzymes, and pathologies of hepatopancreas may have potential as biomarkers for monitoring residual triazine herbicides in the aquatic environment.
authors: Dalibor
authors: D
authors: Koutnik
authors: Alzbeta
authors: A
authors: Stara
authors: Eliska
authors: E
authors: Zuskova
authors: Antonin
authors: A
authors: Kouba
authors: Josef
authors: J
authors: Velisek
mesh_terms: D000818:Animals; D003400:Astacoidea / Q000187:drug effects*; D004781:Environmental Exposure / Q000009:adverse effects*; D006540:Herbicides / Q000633:toxicity*; D059550:Toxicity Tests, Subchronic; D014227:Triazines / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D014877:Water Pollution, Chemical / Q000009:adverse effects*
chemical_list: D006540:Herbicides; D014227:Triazines; D014874:Water Pollutants, Chemical; C009235:metribuzin