Mercury accumulation in barred sand bass (Paralabrax nebulifer) near a large wastewater outfall in the Southern California Bight

Mercury (Hg) concentrations were measured in muscle tissue of barred sand bass (Paralabrax nebulifer; Serranidae) from several locations in the Southern California Bight, including a site adjacent to a large wastewater outfall, to test the null hypothesis that there are no differences between near-outfall and other areas in growth-normalized Hg burdens. Fish otoliths were used for aging, and Hg concentrations in dorsal muscle tissue were evaluated relative to the age of individual fish and between sites. Mercury concentrations were positively correlated with length and age. Significant differences between sites (ANCOVA; p < 0.05) in tissue Hg concentrations were also found. However, length-normalized Hg concentrations in near-outfall fish were not significantly different from those at an adjacent area or from a site largely removed from the effects of wastewater discharges. These results suggest that regional differences in tissue Hg concentrations may be unrelated to the effects of wastewater discharges.