Non-detection of enterovirus in Anadara tuberculosa (Bivalvia : Arcidae) by chemical pollution in the Pacific of Costa Rica

Anadara tuberculosa is one of the most abundant mollusks of commercial impo rtance in Costa Rica. Its habitat water is a potential source of fecal and chemical contamination to humans. We wanted to asses enterovirus, mainly po liovirus and hepatitis A virus and chemicals such as sulphates and nitrates in meat and body fluids. Thirteen samples were taken from four sites in Ni coya Gulf, three sites in the Sierpe-Terraba mangrove (Pacific of Costa Ric a) and from five fish markets in San Jose, the capital of Costa Rica. Sampl es were tested for 1) fecal coliforms (Most Probable Number/100 mi), 2) iso lation of enterovirus in cell culture (Hep-2, FrhK-4), 3) cell cytotoxicity in Vero cells and 4) the ability to inactivate 10 ID50% of poliovirus in c ell culture. The Most Probable Number/100 mi in surrounding water was highe r than the accepted standard for recreational waters, although the number o f fecal coliforms in meats and body fluids was lower than in the external w ater. No cytopathogenic agents were isolated, but we found nitrate and sulp hate concentrations that exceeded maxima for human consumption and recreati on. The intrinsic cytotoxicity of the samples was at a 1/8 dilution, but so me samples were cytotoxic at dilutions of 1/128. Body fluids were more cyto toxic than meats, but a positive correlation between cytotoxicity and chemi cal contamination was not determined: apparently other pollutants not ident ified in this study were responsible. Fluid and meat capacity to inactivate 10 ID50% of poliovirus in cell culture was demonstrated. Samples that were toxic for cell cultures also showed a higher percentage of poliovirus inac tivation. Monitoring chemical pollution in these waters is highly recommend ed.