Effects of hexavalent chromium on development of crabs rhithropanopeus harrisii and callinectes sapidus
Bookhout, C.G.; Monroe, R.J.; Forward, R.B.Jr; Costlow, J.D.Jr
Water Air and Soil Pollution 21(1-4): 199-216
ISSN/ISBN: 0049-6979 DOI: 10.1007/bf00163624
Survival of R. harrisii larvae from hatching to 1st crab stage occurred at Na2CrO4 concentrations from 1.1-29.1 ppm. Estimated LC50 for complete zoeal development was 17.8 ppm Na2CrO4 and it was 13.7 ppm for development to 1st crab stage. A concentration of 1.1 ppm Na2CrO4 was nontoxic, while Na2CrO4 concentrations of 7.2 and 14.5 ppm were sublethal and concentrations of 29.1-58.1 ppm were acutely toxic. Low concentrations of Na2CrO4 caused an increase in swimming speed and high concentrations caused a decline. Survival of C. sapidus larvae occurred in Na2CrO4 concentrations from 1.1 to 4.7 ppm. The LC50 for complete zoeal development was estimated to be 2.9 ppm Na2CrO4 and the LC50 for development to 1st crab stage was estimated to be 1.0 ppm Na2CrO4. The total Cr in sodium chromate was 32% by weight (Tacey, 1981), and the total Cr concentrations tested were 32% of the Cr salts given above. Statistical analyses of the data on survival, duration and mortality of larvae were presented.