RESUMO
This study was performed to determine the variation of metals concentrations (Pb, Cd, Zn, and Cu) in surface sediments based on type region development from ten sites on the intertidal coastal zone of the Persian Gulf, Iran. The metals concentrations in surface sediments varied from 0.86 to 180.78 µg g(-1) for Pb, 0.61 to 6.48 µg g(-1) for Cd, 5.99 to 44.42 µg g(-1) for Zn, and 3.01 to 43.33 µg g(-1) for Cu. The quality of the sediments was evaluated based on sediment quality guidelines (effects range-low (ERL) and effects range-medium (ERM) indexes. Biological effects criteria suggest that metals concentrations in sediments were lower than ERM for all sites, but for some sites metals concentrations in sediments were higher than ERL. The present results support the concept that human activities in each region could be a major source of metals pollution input in the aquatic environment.
Assuntos
Sedimentos Geológicos/química , Metais/análise , Poluentes Químicos da Água/análise , Cádmio/análise , Cobre/análise , Monitoramento Ambiental , Oceano Índico , Irã (Geográfico) , Chumbo/análise , Água do Mar/química , Poluição Química da Água/estatística & dados numéricos , Zinco/análiseRESUMO
A total of 174 individuals of rocky oysters (Saccostrea cucullata) and 35 surface sediment samples were collected from seven stations off the intertidal zones of Qeshm Island, Persian Gulf, in order to study the concentration of mercury in oysters' tissues, and to investigate whether mercury concentrations in the edible soft tissues are within the permissible limits for public health. The average mercury concentrations were found as 3.44, 50.66 and 2.29 µg kg(-1) dw in the sediments, soft tissues and shells of the oysters, respectively. Results indicated that the levels of mercury in sediment differed significantly between the stations. In addition, results confirmed that the soft tissues of oysters could be a good indicator of mercury in the aquatic system. In comparison with food safety standards, mercury levels in oysters were well within the permissible limits for human consumption.