Total-Hg and organic-Hg in Cephalopholis fulva (Linnaeus, 1758) from inshore and offshore waters of NE Brazil

To investigate whether source proximity or bioavailability is the major factor controlling both Hg concentration and Hg speciation in marine fishes, total- and organic-Hg content in muscle and liver tissues from different populations of Cephalopholis fulva (piraúna) from inshore and offshore waters of the Brazilian northeastern coast were analyzed. Average total-Hg in muscle (104 ng.g-1 w.w.) and liver (2,865 ng.g-1 w.w.) tissues, as well as organic-Hg concentrations in muscle (169 ng.g-1 w.w.) and liver (1,038 ng.g-1 w.w.), were much higher in the offshore population of C. fulva than in the inshore ones. In the inshore population total-Hg and organic-Hg average concentrations in muscle tissue were similar and reached only 49 ng.g-1 w.w., while in liver they reached 412 ng.g-1 w.w. for total-Hg and 180 ng.g-1 w.w., for organic-Hg. Concentrations of both Hg species in the two populations were higher in liver than in muscle. The average percentage contribution of organic-Hg to the total Hg content was higher in muscle (98-100 percent) than in liver (42-53 percent), but similar between the two populations. Total-Hg and organic-Hg concentrations in muscle and liver from the offshore population showed significant (P < 0.05) positive correlation with fish length. However, in the inshore population only the total-Hg and organic-Hg in muscle tissues correlate significantly with fish size. Although the coastal environments are enriched in total Hg relative to open waters, the significant higher Hg concentrations in the offshore population of C. fulva and the significant correlation found between organic-Hg in liver with fish size suggest higher bioavailability of Hg in offshore waters relative to inshore ones.

As concentrações de Hg-total e Hg-orgânico foram determinadas em diferentes populações de Cephalopholis fulva (piraúna) capturadas em águas costeiras e em bancos oceânicos do litoral nordeste do Brasil. A comparação entre as duas populações permitiu investigar o efeito da proximidade de fontes sobre as concentrações, e a especiação de Hg em músculo e fígado desta espécie. As concentrações médias de Hg-total em músculo (104 ng.g-1 w.w.) e fígado (2,865 ng.g-1 w.w.), assim como as concentrações de Hg-orgânico em músculo (169 ng.g-1 w.w.) e fígado (1,038 ng.g¹ w.w.) foram muito maiores na população capturada nos bancos oceânicos do que na população costeira. Nesta, as concentrações médias de Hg-total e Hg-orgânico na musculatura de C. fulva foram similares e baixas (49 ng.g-1 w.w.), enquanto que atingiram 412 ng.g-1 w.w. de Hg-total e 180 ng.g-1 w.w. de Hg-orgânico no fígado destes animais. As concentrações das duas espécies de Hg foram significativamente maiores no fígado do que na musculatura. A contribuição percentual média de Hg-orgânico para a concentração total de Hg nos peixes foi maior para músculo (98-100 por cento) que para fígado (42-53 por cento), mas semelhante entre as duas populações. As concentrações de Hg-total e Hg-orgânico na musculatura e no fígado de C. fulva mostraram-se positivamente correlacionadas com o tamanho do animal (P < 0,05). Entretanto, na população costeira somente as concentrações destas espécies de Hg na musculatura apresentaram correlações significativas com o tamanho do animal. Embora o ambiente costeiro seja relativamente enriquecido em Hg, em relação aos bancos oceânicos, as maiores concentrações de Hg foram verificadas na população oceânica de C. fulva. A correlação significativa entre Hg-orgânico no fígado e tamanho do animal no fígado sugerem uma maior biodisponibilidade do Hg em águas oceânicas quando comparada às águas costeiras.

Mercury Contents of Scalp Hair by Consumption Pattern of Fishes, Shellfishes and its Products / 예방의학회지

This study was conducted to examine the levels of total and organic mercury in the scalp hair of the elementary school children and adults, and their relalionship with the consumption pattern of fishes and shellfishes. The scalp hair samples were collected from the occipital part of 115 children and 131 adults in costal, urban and rural areas of kyungpook province from June to August 1991. The mercury content was analysed by the atomic absorption spectrophotometer (model IL. 555)with atomic vapor accessory (model IL. 440). The total and organic mercury contents of hair were significantly higher (P<0.01) among the children who prefer fish and/or shellfish (7.728ppm, 6.610ppm), and canned fish and/or fish pastes (6.969 ppm, 5.885ppm) than those who prefer meat(4.822ppm, 3.905ppm) and vegetables(3.974ppm, 3.224 ppm). The children who prefer to eat the canned fish without cooking showed a higher mercury content than the children who prefer to eat it as stew or mixed with vegetables (P<0.01l). There was a dose-response relationship between the intake frequency of canned fish, raw fish and cooked fish and the content of total and organic mercury of hair; the children who eat fish almost everyday showed 2 times higher than those who eat rarely (P<0.0l). The mercury content in the hair of the children who eat raw fish was significantly higher than that of the children who eat boiled or broiled fish (P<0.01). The total and organic mercury contents of adult scalp hair increased with age up to the forties and slightly decreased in the fifties. The mercury contents of those who were engaged in the fishery and raw fish restaurant were 2 times higher than those of the farmers. The mercury content of the persons who were favorite dishes of fish and shellfish were most high, and who prefer raw fish were 2 times higher than those of the persons who prefer vegetables and broiled fish. The contents of total and organic mercury in adult scalp hair showed also a increasing tendency with the intake frequency of raw and cooked fish.