Estimation of heavy metal intake from seafood consumption in the population of Muang district Rayong province

Abstract

Due to increasing concern about the intake of contaminants in foods, this study was performed to determine the exposure of the 316 primary health care voluntary staff of Muang District, Rayong Province to heavy metal contaminants; cadmium (Cd), lead (Pb), arsenic (As) and mercury (Hg) in seafood, and to estimate the health risk. The concentrations of these metals were determined in the 13 most consumed marine species, yellow-tail round scad (Decapterus maruadsi), indian mackerel (Rastrelliger kanagurta), longtail tuna (Thunnus tonggol), yellow stripe trevally (Selaroides leptolepis), ornate threadfin bream (Nemipterus hexodon), black pomfret (Parastromateus niger), spanish mackerel (Scomberomorus commerson), greasy grouper (Epinephelus tauvina), blood cockle (Arca granulose), green mussel (Perna viridis), banana shrimp (Penaeus merguiensis), soft cuttle fish (Sepioteuthis lessoniana) and splendid squid (Loligo duvauceli). The samples were collected from 3 local markets of Muang District, Rayong Province, between January and February 2008. Analysis of the above contaminants was measured by atomic absorption spectrophotometry (AAS). The bivalves had the highest contents of Cd (0.731 µg/g in blood cockle and 0.140 µg/g in green mussel) and Pb (0.096 µg/g in blood cockle and 0.084 µg/g in green mussel), the cephalopods had the highest content of As (7.032 µg/g in soft cuttlefish and 5.807 µg/g in splendid squid), while the highest Hg content was in fish group (0.119 µg/g in spanish mackerel and 0.269 µg/g in greasy grouper). However, the contamination levels of heavy metals were still lower than contamination standard limited level in food issued by the Ministry of Public Health of Thailand, except the total arsenic contents in soft cuttlefish, splendid squid, yellow stripe trevally, ornate threadfin bream and green mussel, which were higher than that limit. The estimated dietary intake of Cd (66.33 µg/person/week). Pb (40.83 µg/person/week), inorganic As (317.32 µg/person/week) and Hg (46.16 µg/person/week) from 13 kinds of seafoods were within the safe limits. It appears that there is no imminent health risk due to heavy metals examined in this study. However, it should be recognized that the subjects may also be exposed to certain contaminants from other foods and sources other than the diet.