Survey of total mercury and methylmercury levels in edible fish from the Adriatic Sea

Total mercury and methylmercury concentrations were measured in the muscle tissue of different fish species from the Adriatic Sea to ascertain whether the concentrations exceeded the maximum level fixed by the European Commission. Large species-dependent variability was observed. The highest total mercury mean concentrations were in benthic (0.20-0.76 microg g(-1) wet wt) and demersal fish (0.22-0.73 microg g(-1) wet wt), while pelagic species showed the lowest levels (0.09-0.23 microg g(-1) wet wt). In 15% of frost fish, in 42% of skate and in 30% of angler fish samples total mercury concentrations exceeded the maximum level fixed by the European Commission (Hg = 1 microg g(-1) wet wt); for the species for which the maximum level was set to 0.5 microg g(-1) wet wt, concentrations exceeding the prescribed legal limit were observed in 6.4% of bokkem, in 6.6% of pandora, in 20% of megrin, in 12.5% of four-spotted megrim, in 16% of striped mullet, in 5.0% of forkbeard and in 5.3% of picarel samples. In all the different species, mercury was present almost completely in the methylated form, with mean percentages between 70 and 100%. Weekly intake was estimated and compared with the provisional tolerable weekly intake recommended by the FAO/WHO Expert Committee on Food Additives. A high exposure was associated with the consumption of only skates, frost fish and angler fish, thought the consumption of the other species, such as, megrim, four spotted megrim, red fish striped mullet and forkbeard, resulted in a weekly intake slightly below the established provisional tolerable weekly intake.

Polychlorinated biphenyl and organochlorine pesticide contamination signatures in deep-sea fish from the Mediterranean Sea

Polychlorinated biphenyl (PCB) and OCP concentrations were determined in the livers of two deep-sea fish species, roughsnout grenadier and hollowsnout grenadier, from the Adriatic Sea. In both species, contaminant concentrations were in the following order: PCBs>DDTs>>HCB. Contaminant load was higher in roughsnout grenadier (PCB: 12,327ngg(-1); DDTs: 5357ngg(-1); HCB: 13.1ngg(-1)) than in hollowsnout grenadier (PCB: 1234ngg(-1); DDTs: 763ngg(-1); HCB 6.3ngg(-1)). PCB patterns were dominated by higher chlorinated congeners (hexa-CBs: 50.3-52.1%, hepta-CBs: 29.6-35.5%, penta-CBs: 8.0-11.1% and octa-CBs :5.2-5.4%). PCBs 138, 153 180 and 187 were the most abundant. Regarding the DDT pattern, p,p'-DDE was prevalent in both species (roughsnout grenadier: 99.7%, hollowsnout grenadier: 90%), suggesting no recent DDT input. In both species, the total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent (TEQ) concentrations (roughsnout grenadier: mean 43.77pg/g, hollowsnout grenadier: mean 20.49pg/g), calculated from non- and mono-ortho PCBs, reached those encountered in marine organisms at higher levels in the trophic chain.

Persistent organic pollutants (PCBs and DDTs) in small size specimens of bluefin tuna (Thunnus thynnus) from the Mediterranean Sea (Ionian Sea)

The concentration levels and pattern distribution of polychlorinated biphenyls (PCBs) and organochlorine pesticides (DDTs), were investigated in liver of small size specimens of bluefin tuna (Thunnus thynnus) from Mediterranean Sea (Ionian Sea). PCB concentrations (average: 526 ng g(-1) lipid wt) were comparable with DDT levels (average: 435 ng g(-1) lipid wt). The specific analysis of PCB congeners revealed a profile dominated by hexa-, penta- and heptachlorinated congeners, while among DDTs, the compounds with the higher concentration was p,p'-DDE, constituting 91.9% of the total DDT. The total 2,3,7,8-TCDD toxic equivalent (TEQs) of coplanar PCBs, including mono- and non-ortho congeners, was 0.55 pg g(-1) wet weight with. The congeners with highest TEQs values were non-ortho congeners followed by mono-ortho ones.

Total and subcellular distribution of trace elements (Cd, Cu and Zn) in the liver and kidney of green turtles (Chelonia mydas) from the Mediterranean Sea

This study investigated the subcellular distribution of Cd, Cu and Zn in liver and kidney of green turtles (Chelonia mydas) stranded along the Italian coast of the South Adriatic Sea (Eastern Mediterranean). Cd and Zn mean concentrations did not differ significantly between liver (4.26microgg(-1) and 34.53microgg(-1), respectively) and kidney (5.06microgg(-1) and 26.39microgg(-1), respectively), whereas the levels of Cu were significantly higher in liver (32.75microgg(-1)) than in kidney (8.20microgg(-1)) (p<0.009). Most of Cd, Cu and Zn was present in hepatic and renal cytosol, and their concentrations increased with total levels in both organs, indicating that cytosol has a crucial role in metal accumulation. Cd and Cu in hepatic and renal cytosol were present mostly in metallothionein fractions (MTs), whereas Zn was fractionated into MTs and high-molecular-weight-substances (HMWS). The comparison with the results of other investigations on individuals of the same species collected in different marine areas shows good agreement relatively to essential metals. For Cd our data are comparable with those encountered in specimens from the Mediterranean Sea (Cyprus) confirming the homogeneity of the area comprising the south-eastern basin of the Mediterranean Sea from an ecological point of view.

Mercury in fish: Concentrationvs. fish size and estimates of mercury intake

Total mercury concentrations were determined in different fish size classes of commercial importance such as, conger eel (Conger conger), starry ray (Raja asterias), forkbeard (Phycis blennoides), frostfish (Lepidopus caudatus), striped mullet (Mullus barbatus), red gurnard (Aspitrigla cuculus) and yellow gurnard (Trigla lucerna) in order to evaluate variations in consumer exposure to mercury as a function of fish consumption of a spectrum of different sizes. The highest mean levels of total mercury were detected in conger eel (0.80 microg g(-1)) and starry ray (0.75 microg g(-1)). Forkbeard (0.67 microg g(-1)), frostfish (0.59 microg g(-1)) and striped mullet (0.55 microg g(-1)) showed slightly lower levels, while red gurnard (0.33 microg g(-1)) and yellow gurnard (0.22 microg g(-1)) exhibited the lowest concentrations. The results of linear regression analysis showed a significant relationship between mercury concentrations and fish size for all species. Consequently, dietary consumption of larger size specimens leads to an increase in the exposure level for consumers. Understanding by consumers of all factors leading to an increase of exposure to mercury is the first step to enable them to make decisions about eating fish.

Polychlorinated biphenyls and other chlorinated organic contaminants in the tissues of Mediterranean loggerhead turtle Caretta caretta

Polychlorinated biphenyls including coplanar congeners and DDT compounds were measured in different organs and tissues (liver, kidney, lung and muscle tissue) of loggerhead turtles Caretta caretta from the eastern Mediterranean Sea. The highest levels of these compounds were found in liver (PCBs: 52.32 ng/g; DDTs: 18.27 ng/g), followed by kidney (PCBs: 19.05 ng/g; DDTs: 5.70 ng/g), lung (PCBs: 12.75 ng/g; DDTs: 3.76 ng/g ) and muscle tissue (PCBs: 4.65 ng/g; DDTs: 1.45 ng/g). PCBs revealed a profile dominated by hexa-, penta- and hepta-chlorinated congeners, while among DDTs, the compound in the greatest concentration was p,p'-DDE, (liver: 85.2%, kidney: 93.6%, lung: 86.4%, muscle tissue: 93.2%). The estimated toxic equivalents (pg TEQs/g wet wt) of non- and mono-ortho PCBs were in the range of 1.54-5.86 pg TEQs/g wet wt. Non-ortho coplanar PCB 77 accounted for more than 90% of the total TEQs leaving to mono-ortho only 2.6-6.2%.

Concentrations and composition of organochlorine contaminants in different species of cephalopod molluscs from the Italian waters (Adriatic Sea)

Persistent organochlorines, such as polychlorinated biphenyls including coplanar congeners and DDT compounds were measured in the liver of different species of mollusc cephalopods: broadtail squid (Illex coindetii), horned octopus (Eledone moschata) and spider octopus (Octopus salutii) collected in two different areas of the Adriatic Sea (central and southern Adriatic Sea). The concentration of PCBs exceeded DDT ones in horned octopus (PCBs: 617.0 ngg(-1) lipid weight, DDTs: 188.0 ngg(-1) lipid weight) and in spider octopus (PCBs: 590.0 ngg(-1) lipid weight, DDTs: 293.0 ngg(-1) lipid weight), while in broadtail squid PCB load (748.0 ngg(-1) lipid weight) was similar to those of DDTs (514.5 ngg(-1) lipid weight). No significant difference in PCB levels was observed among species, while DDT concentrations were higher in broadtail squid than in horned octopus and spider octopus. DDTs composition showed slight differences in relation to species, thought p,p'-DDE was the predominant compound in all cephalopod species (broadtail squid: 88.1%, horned octopus 94.1%, spider octopus: 97.5%). PCB isomer profiles were similar among species being hexachlorinated isomers the most abundant, followed by penta- and heptachlorobiphenyls, while tri- and tetrachlorobiphenyls made up a small percentage of the total PCB residues. Regarding coplanar congeners, non-ortho PCBs were below the detection limit in all samples and the 2,3,7,8-TCDD toxic equivalent (TEQ) concentrations were very low. The influence of biological and ecological factors (size/weight and location) on the bioaccumulation of organochlorine compounds has been discussed.

Occurrence and accumulation of organochlorine contaminants in swordfish from Mediterranean Sea: a case study

Polychlorinated biphenyls including coplanar congeners and DDT compounds were measured in the liver of a teleost species: namely, Xiphias gladius. PCB concentrations (median: 1121 ng/g lipid wt) were comparable with DDT levels (median: 1236 ng/g lipid wt). PCBs revealed a profile dominated by hexa-, penta- and heptachlorinated congeners. Among DDTs, the compound in the greatest concentration was p,p'-DDE, representing 70% of the total DDT burden, followed by o,p'-DDT>p,p'-DDT>p,p'-DDD=o,p'-DDD. Mean total 2,3,7,8-TCDD equivalent of five coplanar PCBs was 8.83 pg/g lipid weight. The isomers with higher TEQs values were non-ortho congeners than mono-ortho ones.

Cadmium and mercury in cephalopod molluscs: Estimated weekly intake

Cadmium and mercury concentrations were measured in the flesh and hepatopancreas of different species of cephalopod molluscs (European squid, common octopus, curled octopus, horned octopus, pink cuttlefish, common cuttlefish) in order to establish whether the concentrations exceeded the maximum levels fixed by the European Commission. In hepatopancreas, the levels of cadmium were substantially higher than those in flesh (flesh 0.11-0.87 microg g(-1) wet weight, hepatopancreas 2.16-9.39 microg g(-1) wet weight), whilst the levels of mercury (flesh 0.13-0.55 microg g(-1) wet weight, hepatopancreas 0.23-0.79 microg g(-1)) were approximately double those in flesh. Concentrations exceeding the maximum permitted limit of cadmium were found in 39.8 and 41.0% of common octopus and pink cuttlefish flesh, respectively. For mercury, concentrations above the limit were found only in octopuses, and precisely in 36.8, 50.0 and 20.0% of flesh samples of common, curled and horned octopus, respectively. In the hepatopancreas, concentrations of cadmium and mercury were above the proposed limits in all the samples examined. The estimated weekly intake of between 0.09 and 0.49 microg kg(-1) body weight for cadmium and between 0.05 and 0.24 microg kg(-1) body weight for mercury made only a small contribution to the provisional tolerable weekly intake (cadmium 1.3-7.0%, mercury 1.0-4.8%) set by the WHO.

Trace elements in loggerhead turtles (Caretta caretta) from the eastern Mediterranean Sea: overview and evaluation

Concentrations of trace elements (Hg, Cd, Pb, Zn, Cu, Fe, and Se) in different organs and tissues (liver, kidney, muscle tissue, spleen, heart, lung, and fat tissue) of loggerhead turtles Caretta caretta from eastern Mediterranean Sea were determined. The highest levels of mercury and cadmium were found in liver (Hg: 0.43 microg g(-1) wet weight; Cd: 3.36 microg g(-1) wet weight) and kidney (Hg: 0.16 microg g(-1) wet weight; Cd: 8.35 microg g(-1) wet weight). For lead the overall concentrations were low and often below the limit of detection. Copper and selenium tended to be higher in liver than in other tissues and organs, while for zinc the concentrations were quite homogenous in the different organs and tissues, except fat tissue (64.7 microg g(-1) wet weight) which showed a higher accumulation of this element. For iron the greatest concentrations were observed in liver (409 microg g(-1) wet weight) and spleen (221 microg g(-1) wet weight).

Cadmium in cephalopod molluscs: implications for public health

Cadmium concentrations were measured in the flesh and hepatopancreas (digestive gland) of 1,392 specimens of different species of cephalopod molluscs (broadtail squid, spider octopus, curled octopus, horned octopus, elegant cuttlefish, and pink cuttlefish) to determine whether maximum levels fixed by the European Commission were exceeded. In all species, mean cadmium concentrations were higher in hepatopancreas than in flesh. Large differences among the different species were also observed. Pink cuttlefish and spider octopus had the highest concentrations for both flesh (spider octopus, 0.77 microg g(-1); pink cuttlefish, 0.87 microg g(-1)) and hepatopancreas (spider octopus, 9.65 microg g(-1); pink cuttlefish, 18.03 microg g(-1)), and the lowest concentrations were encountered in broadtail squid (flesh, 0.13 microg g(-1); hepatopancreas, 2.48 microg g(-1)). The other species had intermediate concentrations of 0.20 to 0.30 microg g(-1) in flesh and 5.46 to 8.01 microg g(-1) in hepatopancreas. Concentrations exceeding the limit proposed by the European Commission (1.00 microg g(-1)) were observed in 44.4 and 40.0% of flesh samples of spider octopus and pink cuttlefish, respectively. The estimated weekly intake, 0.09 to 0.66 microg/kg body weigh, was below the provisional tolerable weekly intake set by the World Health Organization.

Content of mercury and cadmium in fish (Thunnus alalunga) and cephalopods (Eledone moschata) from the south-eastern Mediterranean Sea

Mercury and cadmium concentrations were measured in the flesh and liver (or hepatopancreas) of albacore (Thunnus alalunga) and horned octopus (Eledone moschata) to establish whether the concentrations exceeded the maximum levels fixed by the European Commission. In both species, mercury and cadmium mean concentrations were higher in liver (albacore: mercury = 2.41 microg g(-1) wet wt, cadmium = 9.22 microg g(-1) wet wt; horned octopus: mercury = 0.76 microg g(-1) wet wt, cadmium = 6.72 microg g(-1) wet wt) than in flesh (albacore: mercury = 1.56 microg g(-1) wet wt, cadmium = 0.05 microg g(-1) wet wt; horned octopus: mercury = 0.36 microg g(-1) wet wt, cadmium = 0.33 microg g(-1)). Mercury concentrations exceeding the prescribed legal limit of 1 microg g(-1) wet wt were found in almost all albacore samples (flesh: 71.4%; liver: 85.7%). For horned octopus, concentrations above 0.5 microg g(-1) wet wt were observed solely in hepatopancreas, while in flesh, the concentrations were below this limit in all the samples examined. Of the flesh samples of albacore, 42.8% exceeded the proposed tolerance for cadmium for human consumption, whilst for horned octopus, the established limit was not exceeded in any sample.

Polychlorinated biphenyl residues in deep-sea fish from Mediterranean Sea

Polychlorinated biphenyls including coplanar congeners were measured in the liver of different species of skates and ghostsharks. The mean concentrations of PCBs in skates (314 ng/g wet wt) were comparable with those in ghostsharks (285 ng/g wet wt). The specific analysis of PCB congeners in skates hepatic tissue revealed a profile dominated by hexa-, penta-, and heptachlorinated congeners followed by trichlorobiphenyls, tetra- and decachlorobiphenyls. A different profile dominated by hexa-, tri-, and pentachlorinated congeners, followed by heptachlorobiphenyl and decachlorobiphenyls was found in ghostsharks liver. The estimated 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) of coplanar PCBs in skates and ghostsharks were 0.48 and 0.33 pg/g wet weight, respectively, with mono-ortho congeners PCB105, 118 and 156 contributing more than 90% to the TEQs.

Heavy metal residues in tissues of marine turtles

Heavy metal concentrations in the tissues of marine turtles are presented. The most frequently monitored elements are mercury, cadmium and lead; and the tissues mainly analysed in nearly all the stranded individuals are muscle, liver and kidney. The highest mercury and cadmium levels were found in liver and kidney respectively; the majority of the lead burden existed in bones and carapace, while arsenic was present mainly in muscle tissue. Mercury occurred quite completely as methylmercury in muscle, whereas in liver the main form was the inorganic one. Arsenic was exclusively present in the metallorganic form either in muscle tissue or in liver. Metals in the eggs were mainly present in the yolk. Significantly higher concentration of mercury, copper, zinc and iron were found in yolk than albumen, while shell contained highest levels of manganese and copper. The load of trace metals in these animals strictly correlated with the species seems to depend on their different food behaviour.

Total mercury and methylmercury content in edible fish from the Mediterranean Sea

The objective of this study was to determine the current levels of total mercury and methylmercury in the muscle tissues of different fish species caught in the Mediterranean Sea to ascertain whether these concentrations exceed the maximum level stipulated by the European Commission Decision. Total mercury concentrations in the muscles of skates ranged from 0.18 to 1.85 mg/kg (wet weight) (average, 1.00 mg/kg) while levels of 0.11 to 1.92 mg/kg (wet weight) (average, 0.70 mg/kg) and 0.21 to 1.74 mg/kg (wet weight) (average, 0.70 mg/kg) were recorded for blue whiting and red mullet, respectively. For 66.7% of long nose skate samples, 61.4% of thornback ray samples, 42.8% of winter skate samples, and 38% of starry ray samples, the total mercury concentrations exceeded the prescribed legal limit (1.0 mg/kg [wet weight]). Concentrations exceeding the maximum total mercury level stipulated by the European Commission Decision (0.5 mg/kg [wet weight]) were observed in 63.6 and 40% of blue whiting and striped mullet samples, respectively. Mercury was present in the different species almost completely in the methylated form at 55 to 100%. Weekly intakes were estimated and compared with the provisional tolerable weekly intake recommended by the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives.

Heavy Metal, Polychlorinated Biphenyl and Organochlorine Pesticide Residues in Marine Organisms: Risk Evaluation for Consumers

This survey provides information on the levels of heavy metal, polychlorinated biphenyl and organochlorine pesticide residues in marine organisms to ascertain whether these concentrations exceeded the prescribed legal limits. In order to assess the potential human health impact, the weekly intake was estimated. Most of the organisms analysed showed higher levels of mercury than the maximum permissible limit, while cadmium and lead were below the proposed permissible limits in all samples. The estimated intake was far above the established Provisional Tolerable Weekly Intake for all metals, except for total mercury.

Levels and congener pattern of polychlorinated biphenyls in the blubber of the Mediterranean bottlenose dolphins Tursiops truncatus

Isomer specific concentrations of individual polychlorinated biphenyls (PCBs) including toxic non-ortho (IUPAC 77, 126, 169) and mono-ortho (105, 118, 156) coplanar congeners were determined in the blubber of nine bottlenose dolphins (Tursiops truncatus) stranded along the Eastern Italian coast. The total PCB concentrations ranged from 3534 to 24375 ng/g wet wt. The PCB profile was dominated by congeners 138 and 153 collectively accounting for 55% of the total PCB concentrations. Among the most toxic congeners the order of abundance was 126>169>77. The mean total 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalent of six coplanar PCBs in the blubber of bottlenose dolphins was 45596 pg/g. Non-ortho congeners contributed greater to the 2,3,7,8-TCDD toxic equivalents than mono-ortho members. Particularly, PCB 126 was the major contributor to the estimated toxic potency of PCBs in dolphins.

Total and methylmercury residues in cartilaginous fish from Mediterranean Sea

Concentrations of mercury and methylmercury residues were determined in the muscle tissue of three cartilaginous fishes Chimaera monstrosa (ghostshark), Torpedo nobiliana (electric ray) and Myliobatis aquila (eagle ray) from the Mediterranean Sea. The highest mean levels of total mercury were detected in ghostshark (3.14 mg/kg wet weight), followed by electric ray (2.42 mg/kg wet weight), and eagle ray (0.83 mg/kg wet weight). Such a variability is influenced by quite a number of factors, among which size, fish ecology and feeding habits. The percentages of the methylated form to total mercury ranged from a minimum of 72% in eagle ray to a maximum of 83% in ghostshark. Relationship between specimen size and mercury and methylmercury concentrations were found in ghostshark species.

Total and methylmercury residues in tuna-fish from the Mediterranean sea

This study was carried out to determine the current levels of total mercury and methylmercury in the muscle tissue of albacore (Thunnus alalunga) and bluefin tuna (Thunnus thynnus) caught in the Mediterranean sea with the purpose of ascertaining whether the concentrations exceeded the maximum level fixed by the European Commission Decision. Total mercury concentrations ranged from 0.84 to 1.45 mg kg(-1) w.w. (av. 1.17 mg kg(-1) w.w.) and from 0.16 to 2.59 mg kg(-1) (av. 1.18 mg kg(-1) w.w.) in the muscle of albacore and bluefin tuna, respectively. In 78.6% of albacore and in 61.1% of bluefin tuna analysed, total mercury concentrations exceeded the maximum level fixed by the European Commission Decision (Hg = 1 micro g g(-1) wet wt). In the two species, mercury was present almost completely in the methylated form, with percentages between 77 and 100% (av. 91.3%) in albacore and between 75 and 100% (av. 91%) in bluefin-tuna. In order to assess the potential health impact, the estimated weekly intake was calculated. The estimated weekly intake was far above the established Provisional Tolerable Weekly Intake for both species.

Persistent organochlorine residues and toxic evaluation of polychlorinated biphenyls in sharks from the Mediterranean Sea (Italy)

Persistent organochlorines such as polychlorinated biphenyls including coplanar congeners, DDT compounds and HCB were measured in different tissues (muscle, liver and eggs) of two Mediterranean shark species: namely Centrophorus granulosus and Squalus blainvillei. The concentrations of organochlorines in the tissues and organs of both species were in the order DDTs > PCBs > HCB. The highest values of DDTs, PCBs and HCB were found in liver followed by eggs and muscle. Among DDTs the compound found in greatest concentration was p,p'-DDE. The PCB profiles were dominated by congeners 138, 153, and 180. The isomers with higher TEQs values were non- and mono-ortho congeners than di-ortho ones in muscle, liver and eggs of both species. Among the non-ortho, PCB 126 was the major contributing individual to the total TEQs in both species.

Total, organic, and inorganic arsenic in some commercial species of crustaceans from the Mediterranean Sea (Italy)

Total, organic, and inorganic arsenic were measured in the flesh of different crustacean species: Parapenaeus longirostris, Aristeus antennatus, Plesionika martia, and Nephrops norvegicus, species extensively commercialized and widely consumed as food. Among the different species of crustaceans, the highest mean value of total arsenic was detected in N. norvegicus (45.00 microg g(-1) dry wt), followed by P. martia (40.76 microg g(-1) dry wt), P. longirostris (34.00 microg g(-1) dry wt), and A. antennatus (15.45 microg g(-1) dry wt). In all the species examined, most of this element was present as organic compounds, while inorganic arsenic was only a very modest percentage (3.5 to 5.7%) of the total arsenic present. There is a substantial epidemiological evidence that inorganic arsenic may cause lung and skin cancer. For this reason, the Joint Expert Committee of the FAO-WHO recommended a maximum acceptable daily intake of inorganic arsenic for humans of 2 microg/kg of body weight. The estimated daily intake was below this limit; therefore, no direct hazard for human health due to the consumption of this seafood was found.

Total mercury levels in muscle tissue of swordfish (Xiphias gladius) and bluefin tuna (Thunnus thynnus) from the Mediterranean Sea (Italy)

This study was carried out to determine the current levels of total mercury in the muscle tissue of swordfish (Xiphias gladius) and bluefin tuna (Thunnus thynnus) caught in the Mediterranean Sea with the purpose of ascertaining whether the concentrations exceeded the maximum level fixed by the European Commission Decision. In addition, specimens of each species were divided into different ranges of weight to investigate the influence of size on mercury accumulation in order to provide data upon which commercial fishing strategies and marketing of swordfish and bluefin tuna may be based. Higher mean levels of total mercury were found in bluefin tuna (1.02 microg g(-1) wet wt) than in swordfish (0.49 microg g(-1) wet wt). In 4.3% of swordfish and in 44.3% of bluefin tuna analyzed, total mercury concentrations exceeded the maximum level fixed by the European Commission Decision (Hg = 1 microg g(-1) wet wt). Besides, for bluefin tuna the total mercury level variability observed, due to size, suggests that there should be greater regulatory control by the authorities.

Heavy metals in the aquatic environment of the Southern Adriatic Sea, Italy: macroalgae, sediments and benthic species

Samples of sea urchins (Paracentrotus lividus), holothurians (Holothuria polii), green algae (Ulva lactuca. Codium vermilara and Enteromorpha prolifera) and sediments were collected from different coastal zones of the South Adriatic Sea (Italy). The occurrence of metals in macroalgae is poor especially if compared with that reported in other coastal areas affected by human activities, with the exception of Fe that showed high mean values (405 microg g(-1) dry wt.). Likewise, relationships between metal concentrations in holothurians and sediments were found, demonstrating that H. polii could serve as bioindicator for Hg and Cu.

Consumption of bivalve molluscs in Italy: estimated intake of cadmium and lead

Concentrations of cadmium and lead were determined in nine different species of mollusc bivalves (Modiolus barbatus, Venus verrucosa, Scapharca inaequivalvis, Tapes decussatus, Callista chione, Pecten jacobeus, Ensis siliqua, Venus gallina, Cardium tubercolata) collected from different coastal areas of the Adriatic Sea (north, middle and south Adriatic). The levels of cadmium and lead found in bivalves from the north Adriatic Sea were significantly (P < 0.001) higher than those detected in those from the middle and south Adriatic Sea. In some species of molluscan bivalves (M. barbatus and T. decussatus) from the north Adriatic Sea, concentrations of cadmium and lead exceeded the maximum limit (2 mg/kg w.w.) established by the Italian legislation. Weekly intakes were estimated and compared with the Provisional Tolerable Weekly Intake (PTWI) recommended by the FAO/WHO Expert Committee on Food Additives.

Polycyclic aromatic hydrocarbons in mussels (Mytilus galloprovincialis) from the Ionian Sea, Italy

Concentrations of eight polycyclic aromatic hydrocarbons (PAHs) (phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[ghi]perylene) were determined in mussels (Mytilus galloprovincialis) collected between June and September 1995 from 10 locations along a sound of sea formed by two inlets (Mar Piccolo) close to the Gulf of Taranto (Ionian Sea, Italy). In mussels the concentrations of total PAHs were between 14.8 and 645.3 microg/kg wet weight. Among the single identified compounds, the predominance of phenanthrene (29.5 microg/kg wet weight) and anthracene (64.7 microg/kg wet weight) was evident. Another relevant pollutant was pyrene (18.4 microg/kg wet weight) followed by fluoranthene (7.2 microg/kg wet weight), whereas the other compounds showed low levels. The mussels that showed the highest total concentrations of PAHs were collected from stations affected by stronger human activities (industrial fallout, urban wastewaters, and contaminants transported via riverine discharge). Our results were similar to those found in areas classified as moderately polluted. This observation suggests the need for an increased effort in controlling sources of pollution in this area recognized as one of the most productive mussel-farming areas in the Italy.

Fish for human consumption: risk of contamination by mercury

Total mercury concentrations were measured in the muscle of different kinds of fish: megrim (Lepidorhombus boscii), common sole (Solea vulgaris), striped mullet (Mullus barbatus), anglerfish (Lophius piscatorius), and black-bellied angler (Lophius budegassa), caught in the South Adriatic Sea (South Italy). The highest total mercury levels were found in anglerfish (0.61-2.22 mg/kg wet wt, mean 1.26 +/- 0.58), followed by black-bellied angler (0.22-1.62 mg/kg wet wt, 0.68 +/- 0.36), megrim (0.05-0.92 mg/kg wet wt, 0.39 +/- 0.30), striped mullet (0.10-0.63 mg/kg wet wt, 0.31 +/- 0.13) and common sole (0.05-0.44 mg/kg wet wt, 0.19 +/- 0.15). According to current regulations, 62.5% of anglerfish (Lophius piscatorius) and 23% of black-bellied angler (Lophius budegassa) samples showed concentrations exceeding the peak value of 1 mg/kg, while only 25% of samples of megrim (Lepidorhombus boscii), and 8.3% of striped mullet (Mullus barbatus), exceeded the peak value fixed at 0.5 mg/kg. Correlations between total mercury concentration and specimen weight were evident in all the species examined.

Organic and inorganic arsenic and lead in fish from the South Adriatic Sea, Italy

Total, organic and inorganic arsenic and lead were measured from the muscle of different kinds of fish: skate (Raje spp.), hake (Merluccius merluccius) and blue whiting (Micromesistius poutassou), caught in the South Adriatic Sea (South Italy) in the period June-August 1995. The highest levels of total arsenic were found in skate (Raje spp.) whose values ranged from 14.4 to 61.5 mg/kg ww, followed by blue whiting (M. poutassou) and hake (M. merluccius) that showed lower levels ranging from 8.5 to 21.5 mg/kg ww and from 5.9 to 16.1 mg/kg ww, respectively. In all the species examined most of this element was present as organic compounds while inorganic arsenic was only a very modest percentage (0.47-3.5%) of the total arsenic present. Lead in all species analysed was at small concentrations with mean values ranging from 0.12 to 0.15 mg/kg ww. According to the rules in force in Italy no samples showed concentrations of lead exceeding the peak value of 2 mg/kg.

Heavy metals in mussels (Mytilus galloprovincialis) from the lonian Sea, Italy

Concentrations of six heavy metals (Hg, Pb, Cd, Cr, Zn, and Sn) were determined in mussels (Mytilus galloprovincialis) collected between June and September 1997 from 10 locations along a sound formed by two inlets (Mar Piccolo) near the Gulf of Taranto (Ionian Sea, Italy). The average concentrations of the heavy metals found in mussels samples were 0.15 mg/kg for Hg, 1.19 mg/kg for Pb, 0.64 mg/kg for Cd, 0.31 mg/kg for Cr, 5.15 mg/kg for Zn, and 0.54 mg/kg for Sn. The concentrations of heavy metals in mussels from the first inlet did not differ greatly from those observed in mussels from the second inlet. The concentrations of heavy metals in the mussels analyzed were below acceptable levels for human consumption.

Cadmium and total mercury in some cephalopods from the South Adriatic Sea (Italy)

In the framework of a wide monitoring programme on the presence of heavy metals in marine organisms caught in the South Adriatic Sea, cadmium and total mercury concentrations were determined in flesh and hepatopancreas of 512 specimens of two species of cephalopods. The aim of the study was to establish the quality of the marine food with respect to the health of consumers and to investigate cadmium and mercury distribution in organisms representing different habitats. For both elements, higher levels were found in spider octopus (Octopus salutii) than in broadtail squid (Illex coindeti). Between the two different tissues analysed, higher concentrations were observed in hepatopancreas than flesh. According to the rules in force, no flesh sample showed cadmium and total mercury concentrations exceeding the peak permitted values of 2 mg/kg wet wt and 0.5 mg/kg wet wt respectively.

Total mercury in muscle of benthic and pelagic fish from the South Adriatic Sea (Italy)

Total mercury concentrations were measured from the muscle of different kinds of fish: yellow gurnard (Trigla lucerna), red gurnard (Aspitrigla cuculus) red fish (Helicolenus dactylopterus), skate spp. (Raje spp.), goldline (Sarpa salpa), atlantic bonito (Sarda sarda), mackerel (Scomber scombrus), chub mackerel (Scomber japonicus) caught in the South Adriatic Sea (south Italy) in the period June/August 1995. The highest total mercury levels were found in the benthic marine organisms and particularly in skates (Raje spp.) whose values ranged from 0.05 to 2.65 mg/kg wet wt with a mean value of 1.02 mg/kg wet wt. As for pelagic species, the highest mean levels were observed in Atlantic bonito (0.34 mg/kg wet wt), while in goldline the mean content of total mercury was the lowest (0.07 mg/kg wet wt). According to the rules in force (Official Journal of the European Communities 1994) 53% of skate and Atlantic bonito samples showed concentrations exceeding the peak value of 1 mg/kg, while for the other species, only 28% of samples exceeded the peak value fixed at 0.5 mg/kg. Correlations between total mercury concentration and specimen weight were evident in all examined species except for goldline and skates.

Pharmacokinetics of N-methylglucamine antimoniate after intravenous, intramuscular and subcutaneous administration in the dog

The pharmacokinetic profile of antimony in dogs was defined by administering it intravenously, intramuscularly and subcutaneously as N-methylglucamine antimoniate at a dose of about 25.65 mg of antimony kg-1 bodyweight. The results showed a different half-life for the three routes of administration: 20.5, 42.1 and 121.6 minutes for the intravenous, intramuscular and subcutaneous routes, respectively; peak time values (Tmax) were also different for the intramuscular (90 to 120 minutes) and subcutaneous (210 to 240 minutes) injection. The apparent bioavailability of antimony was > 100 per cent for the intramuscular and 100 per cent for the subcutaneous routes. The data obtained showed a relevant difference in the behaviour of the drug in the dog in comparison to that in humans.