Fine-tuning metallothionein as a biomarker for arsenic exposure in feral juvenile winter flounder

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:392327

Jessen-Eller, K; Crivello, J ^[1]

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1. Univ. of Connecticut, Groton, CT (United States). Marine Science Dept.

Metallothionein (MT) is a promising biomarker for assessing metal bioavailability and synergism impact on commercially important species such as the winter flounder (Pleuronectes americanus). The authors investigated whether arsenic induces in juvenile winter flounder from the Long Island Sound because these fish showed high levels of hepatic arsenic (up to 270 ppm; mean 15 ppm). Hepatic arsenic concentrations increased in a dose dependent manner 24 hr. after juveniles (mean length of 120 mm) were subcutaneously implanted with silastic tubing containing sodium arsenite (1.5, 3.0, 6.0 and 16.0 umols/g fish). Death occurred when hepatic arsenic levels exceeded 18 ppm with 0%, 18%, 20%, and 40% mortality at each respective treatment. Both the MT message and protein were significantly elevated (p < 0.05) above baseline (7.5 fold and 2 fold respective increase) across all four treatments. However, total arsenic levels did not significantly differ from the controls at the 1.5 umols/g fish level. This suggested that MT is a more sensitive indicator of arsenic exposure than the total liver arsenic burden when the level of exposure is environmentally realistic (e.g. near baseline). It also showed that the MT cellular response had reached its maximum at the 1.5 umols/g fish sodium arsenite level. When the experiment was repeated with a lower dose regime (0.75, 1.5 and 3.0 umols/g fish) and smaller fish (mean length of 80 mm), the baseline MT message level was the same as in the previous experiment. Also, as in the previous experiment, arsenic accumulated up to 100 ppm and 21% mortality occurred at the 3.0 umols/g fish treatment. The two experiments differed that the MT levels of the vector control were significantly (p < 0.05) lower than baseline. This resulted in a respective dose dependent increase MT message of 8, 100 and 1,000 fold above the vector control and vastly improved MT`s sensitivity as a biomarker.

• OSTI ID: 392327
• Report Number(s): CONF-9511137--; ISBN 1-880611-03-1
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
ARSENIC
BIOLOGICAL INDICATORS
BIOLOGICAL MARKERS
BIOLOGICAL STRESS
BIOSYNTHESIS
DOSE-RESPONSE RELATIONSHIPS
FISHES
LONG ISLAND SOUND
METALLOTHIONEIN
TOXICITY
WATER POLLUTION