Toxic and accumulatory effects of naphthalene on the blue crab, Callinectes sapidus
Walker, Margaret A.
Master of Science
Volatilization of soluble naphthalene proved to be a major factor in toxicity reduction. Static toxicity tests showed juvenile crabs to be resistant to moderately high initial naphthalene concentrations (48 hour TLJm= 12 ppm). However, chronic levels of naphthalene between 1 and 2 ppm proved lethal. The relevance of these two bioassay methods to investigation of oil pollution is discussed. Accumulation of naphthalene by adult blue crabs was found to be an osmotic process dependent upon the soluble naphthalene concentration. Concentration magnification did not occur. In clean seawater, depuration of accumulated naphthalene was rapid and complete within one week. Excretion of unchanged naphthalene was the major process of depuration. The threat to public health from consumption of naphthalene-contaminated crabs is minimal. Blue crabs were able to metabolize naphthalene to 1-naphthol, naphthalenediol, and an unidentified conjugate. Detoxification was carried out on less than 1% of the injected C-naphthalene. These metabolites were isolated and identified by radiography of thin layer chromatograms.