The toxicity and physiological effects of oil and petroleum hydrocarbons on estuarine grass shrimp Palaemonetes pugio (Holthuis)

Abstract

Investigations of the effects of oils and petroleum hydrocarbons on Palaemonetes pugio (Holthuis) have revealed that they are susceptible to refined oils (No. 2 fuel oil and Bunker C residual oil) when exposed to sea water containing 1 to 4 ppm oil hydrocarbons. Four day old larvae (second zoea) were more susceptible than either postlarvae or adults. Kuwait and South Louisiana crude oils were found to be less toxic. Eight petroleum hydrocarbons were lethal to adult shrimp in 48h at levels below 35 ppm. Of these, the naphthalenes were toxic at concentrations near 1 ppm. Environmental stresses of increased temperature and decreased salinity enhanced the toxicity of the hydrocarbons. Animals exposed to dodecyl sodium sulfate, a standard toxicant, varied their response with the season of capture and length of time in the laboratory. Shrimp collected from December to February were less vigorous than those collected at other times. Shrimp maintained for over two weeks in the laboratory were more sensitive to the toxicant than freshly collected organisms. Grass shrimp have been found to accumulate petroleum hydrocarbons from sea water. Ultraviolet spectrophotometry was utilized to determine the concentration of naphthalenes in sea water and shrimp tissue. This technique showed that hydrocarbons are accumulated in from 1 to 8 or less.