MONITORING OF OYSTERS AND SEDIMENTS IN ACAJUTLA, EL SALVADOR

Oysters (Ostrea irridescens) and fine-grained sediments from Acajutla, El Salvador were analysed for petroleum hydrocarbons, chlorinated org anic compounds, pesticides and trace elements. Most oysters contained only background levels of PAHs, with the exception of those collected very close to an industrial discharge canal which were up to 100 times background levels. Only black mud accumulating in the main harbour co ntained PAHs at levels of environmental concern. Pesticides in oysters and fine-grained sediments were below the detection levels in most sa mples. PCBs were also low. Trace elements in sediments and oysters var ied widely, reflecting differences in loadings and degree of bioavaila bility. Zinc and copper in oysters were elevated to levels normally co nsidered representative of moderately polluted sites, whereas arsenic, cadmium, chromium, lead and nickel were not elevated at most sites. T hese results were generally associated with potential sources of conta mination identified through a questionnaire on product storage, handli ng and waste disposal from facilities operating in the area. (C) 1998 Elsevier Science Ltd. All rights reserved.