Recreational and subsistence stream fisheries of Puerto Rico: Are there contaminant concerns?

Thousands of chemicals are released annually into the environment with a variety of adverse effects.  Water pollution is of particular concern for densely populated areas like Puerto Rico, but few contaminant studies have been conducted on the island and none have examined stream ecosystems.  Our objectives were to quantify occurrences of PAHs, pesticides, PCBs, and heavy metals in the habitat and biota of Puerto Rico streams.  We sampled water, sediment, and native fish and shrimp species that may be pursued in fisheries and evaluated their contaminant burdens in relation to ecological and human health at 13 sites spanning diverse land use patterns.  Overall, water contaminant concentrations were below available established protective criteria.  All organic and most metal (cadmium, lead, mercury, zinc, selenium) contaminants in stream sediment were below criteria values.  However, sediment at 8 of 13 sites exceeded nickel criteria, and sediment at all sites exceeded copper criteria.  Organic contaminant concentrations were generally greater in mountain mullet (<i>Agonostomus monticola</i>), river goby (<i>Awaous banana</i>), and American eel (<i>Anguilla rostrata</i>).  Metal concentrations varied among species.  These results and more intensive sampling will provide natural resource managers with the scientific information needed to guide fisheries management and human health risk assessments.