Seasonal bioaccumulation of toxic trace elements in economically important fish species from the Caspian Sea using GFAAS

This study aimed to determine the concentrations of aluminium, cadmium, lead and nickel in edible muscle of three commercially valuable fish species (Rutilus frisii kutum, Liza aurata and Cyprinus carpio) from four fishing sites of Iranian coastal waters of the Caspian Sea during winter and summer. The samples were analyzed using graphite furnace atomic absorption spectrometry (GFAAS) after wet-ashing digestion. The results were expressed as μg/g of wet weight. The resulted range of metals in fish species was between 0.89–2.46 μg/g for aluminium, 0.03–0.17 μg/g for cadmium, 0.21–0.38 μg/g for lead and 0.12–0.52 μg/g for nickel. Seasonal variation influenced concentration of the metals in fish samples of some fishing sites. The highest concentrations found were 4.63 μg/g for aluminium in winter and 0.82 μg/g for lead in summer in Cyprinus carpio; while cadmium (0.49 μg/g) and nickel (1.14 μg/g) were the highest in Rutilus frisii kutum in winter. This demonstrates that estimated daily and weekly intakes of aluminium, lead and nickel and estimated monthly intake of cadmium via consumption of fish flesh are below the established PTDI, PTWI and PTMI values.     

Investigation of heavy metal levels in economically important fish species captured from the Tuzla lagoon

Two hundred fish samples were collected seasonally from November 2000 to December 2001 from the Tuzla Lagoon. Heavy metal (Cd, Pb, Cu, Zn, and Fe) concentrations were measured in the muscle, gill, liver and gonad of three fish species (Sparus aurata, Dicentrarchus labrax and Mugil cephalus). The concentrations of heavy metals were determined by using flame atomic absorption spectrophotometry (FLAAS) and graphite furnace atomic absorption spectrophotometry (GFAAS) after wet digestion method.     

Metal levels in economically important bivalve species from Turkey

Concentrations of eight heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) were determined in economically important bivalve species: oyster (Ostrea edulis), wedge clam (Donax trunculus), manila clam (Ruditapes philippinarium) and warty clam (Venus verrucosa) from the Marmara and Aegean seas. Samples were collected seasonally between 2008 and 2009. Metal levels of bivalves were found in the following ranges: As 0.02–3.40, Cd 0.02–2.80, Cr 0.19–0.82, Cu 0.82–25.06, Hg?<?LOD–0.12, Ni 0.09–0.73, Pb 0.05–4.16 and Zn 6.85–899?mg?kg^?1. The most abundant elements were Zn?>?Cu?>?As. In addition, the results showed that oysters had the highest concentrations of Zn in all seasons. The next abundant heavy metal detected was Cu in oyster and other clam species. It was concluded that in the future, these metals should be monitored regularly.     

食用菌富集微量元素的研究进展

微量元素是一类人体所必需的营养素,在自然界中多数以无机态形式存在,且分布不平衡,不易被人体吸收利用。近年来许多研究显示,食用菌对微量元素锌、硒、碘、铁等都具有富集和将无机态微量元素转化成有机态的功能。本文对食用菌富集微量元素的机理进行了归纳总结,概述了灵芝、香菇和金针菇等各类食用菌对微量元素的富集作用的研究进展。      

鱼油中重金属元素的质谱分析

建立了电感耦合等离子体质谱(ICP-MS)法测定鱼油中Cr、Co、Ni、As、Mo、Cd、Sn、Sb、Hg、Pb等10种重金属元素的分析方法。采用微波消解法消解样品后直接进行分析,应用碰撞/反应池(ORS)技术有效地消除了多原子离子对待测元素的干扰,选用Sc、Rh、Bi等元素为内标混合液校正基体干扰和漂移。结果表明,该方法的检出限为0.008～0.073μg/L,相对标准偏差均小于4.4%,通过添加标准回收实验,回收率在89.6%～103.8%。该法简便、快速,能满足鱼油中多种微量重金属元素同时测定的分析需求。     

Seasonal evaluation of nutritional benefits of two fish species in the eastern Mediterranean Sea

Fish are a good nutritional source of proteins, essential fatty acids and minerals. Societies with high fish intake have lower rates of acute myocardial infarctions and atherosclerosis, better cognitive functions, and better neural and visual development in foetuses. In the present work, we evaluated seasonal variation in proximate composition of two commercial fish species, the rabbitfish Siganus rivulatus, an algaevore, and the white sea bream Diplodus sargus, a carnivore from the eastern Mediterranean. Fifteen fish were collected on the second weekend of each of 8 months covering the four seasons. Results show that the nutritive value of a species of fish varies throughout the year. Furthermore, rabbitfish tissue generally contains more lipids than white sea bream, and fillet yield from rabbitfish is greater than from sea bream. As both fish are sold at a similar price in Lebanese markets, results suggest that rabbitfish offers better value for the price than does white sea bream.     

Total lipid content and fatty acid composition of commercially important fish species from the Mediterranean, Mar Grande Sea

The fatty acid (FA) profiles of 11 commercially important fish species from the sea of Southern Italy (Mar Grande Sea) were investigated.The results showed significant differences among the fatty acid profiles of the examined fish (p < 0.05). A relatively high proportion of n − 3 polyunsaturated fatty acids (PUFAs), of which more than 70% were accounted by docoesahexaenoic acid (DHA) and eicoesapentaenoic acid (EPA) in salema, bogue, common two-banded seabream and sand smelt, and lower proportions of oleic acid (C18:1n − 9) and palmitic acid (C16:0) also dominating. The percentages of EPA and DHA were between 5.03-8.61% and 9.85-17.39% of total lipid, respectively.The results showed that the fish examined are a good source of n − 3 PUFAs, resulting in a very favourable n3 - n6 ratio, especially in salema, sand smelt, common two-banded seabream and picarel.     

Determination of 20 trace elements in fish and other seafood from the French market

The levels of 20 essential or toxic trace elements in 159 fish, other seafood and seafood products on the French coastal market collected between January and April 2005 were measured by ICP-MS. The concentration ranges (mg/kg of fresh mass) for the elements determined were compared with previous studies. The contents of Co, Cu, Fe, Li, Mn, Se, Zn and Pb found in fish are close to or often lower than previous studies. For other seafood, comparison is difficult due to the lack of data on a more global scale. However, it should be noted that the contents of Ag were found considerably higher in this study.     

Optimisation of the supercritical extraction of toxic elements in fish oil

This study aims to optimise the operating conditions for the supercritical fluid extraction (SFE) of toxic elements from fish oil. The SFE operating parameters of pressure, temperature, CO₂ flow rate and extraction time were optimised using a central composite design (CCD) of response surface methodology (RSM). High coefficients of determination (R²) (0.897–0.988) for the predicted response surface models confirmed a satisfactory adjustment of the polynomial regression models with the operation conditions. The results showed that the linear and quadratic terms of pressure and temperature were the most significant (p < 0.05) variables affecting the overall responses. The optimum conditions for the simultaneous elimination of toxic elements comprised a pressure of 61 MPa, a temperature of 39.8ºC, a CO₂ flow rate of 3.7 ml min^?1 and an extraction time of 4 h. These optimised SFE conditions were able to produce fish oil with the contents of lead, cadmium, arsenic and mercury reduced by up to 98.3%, 96.1%, 94.9% and 93.7%, respectively. The fish oil extracted under the optimised SFE operating conditions was of good quality in terms of its fatty acid constituents.     

Metal content determination in four fish species from the Adriatic Sea

Concentrations of As, Cd, Cu, Hg and Pb were measured by atomic absorption spectrometry (AAS) in muscle tissues of four fish species: anchovy (Engraulis encrasicholus), mackerel (Scomber japonicus), red mullet (Mullus surmuletus) and picarel (Spicara smaris) from the Croatian waters of the Adriatic Sea during 2008 and 2009. Metal levels measured in anchovy were in the following ranges (mg kg⁻¹): As 0.01–54.8, Cd 0.001–0.02, Cu 0.001–6.29, Hg 0.001–0.52 and Pb 0.001–0.34 mg kg⁻¹. Metal ranges in red mullet were (mg kg⁻¹): As 0.01–70.9, Cd 0.002–0.85, Cu 0.001–57.3, Hg 0.001–2.07 and Pb 0.001–0.27 mg kg⁻¹. Metal level ranges measured in mackerel were (mg kg⁻¹): As 0.01–36.4, Cd 0.001–0.1, Cu 0.001–15.9, Hg 0.001–0.78 and Pb 0.002–0.24 mg kg⁻¹. In picarel, metal level ranges were (mg kg⁻¹): As 0.01–54.6, Cd 0.001–0.1, Cu 0.08–32.9, Hg 0.001–0.207 and Pb 0.001–0.46 mg kg⁻¹. Significant differences in metal concentrations were found among fish species. The results presented on metal contents in the examined species give an indication of the environmental conditions. Concentrations of Cd, Cu, Hg and Pb obtained were far below the established values by the European Community regulations. However, arsenic levels found in red mullet were higher than the recommended legal limits for human consumption and as such may present a human health issue.     

Essential elements and contaminants in tissues of commercial pelagic fish from the Eastern Mediterranean Sea

BACKGROUND: It is important to determine the concentrations of essential and non‐essential metals in fish for human health. The essential elements and contaminants (Pb and Cd) were determined seasonally in the muscle and liver of some pelagic fish species round herring (Etrumeus teres), chub mackerel (Scomber japonicus), golden grey mullet (Liza aurata) and Mediterranean horse mackerel (Trachurus mediterraneus) from the Iskenderun Bay, Eastern Mediterranean Sea. RESULTS: The Na, K, Ca and Mg were the most abundant elements in muscle and liver tissues. The Na, K, Ca and Mg concentrations in fish tissues were between 51.7 and 3426 mg kg^?1. Muscle accumulated the lowest levels of elements. Trace element and contaminant levels in muscle were highest in spring and summer. The Cu, Zn and Cr concentrations were highest in summer. The Ni, Mn and Fe concentrations were highest in spring. The maximum Pb concentrations in the muscle and liver of fish species was 0.39 and 0.80 mg kg^?1 in autumn. The maximum Cd concentration in the muscle of fish was 0.27 mg kg^?1 in spring and the maximum Cd concentration in the liver was 0.78 mg kg^?1 in summer. CONCLUSION: The Cr, Pb, Cd, Cu and Zn levels in muscle were found to be lower than permissible limits reported by various authorities. Estimated weekly and daily intake for Pb and Cd by consumption of fish muscle were far below the PTWI and PTDI values established by FAO/WHO. Copyright © 2009 Society of Chemical Industry     

Comparison of trace elements in milk of four species.

The objective of this study was to compare trace elements in milks of four species. Milk samples of 4 ml or more were obtained from guinea pigs, dairy cattle, horses, and humans. The milks were analyzed for the trace elements Al, B, Ba, Cu, Fe, Li, Mn, Mo, Si, Sr, Ti, and Zn by inductively coupled argon plasma spectroscopy. Zinc ranged from more than 4 ppm in guinea pig milk to less than 2 ppm in mare milk. Strontium was over 1 ppm in the milk of guinea pigs and less than .1 ppm for the human. Iron ranged from over .7 ppm for the guinea pig to less than .2 ppm for the cow. Copper was over .5 ppm in guinea pig milk and only .05 ppm for cow milk. Boron ranged from .59 to .10 ppm, Si from .58 to .16 ppm, Al from .45 to .10 ppm; and Ba from .22 to .08 ppm in milks of the four species studied. Titanium ranged from a trace to .11 ppm. Lithium, Mn, and Mo all were less than .04 ppm. Milk Mn was surprisingly low relative to bodily needs.     

Survey of 13 trace elements of toxic and nutritional significance in rice from Brazil and exposure assessment

Twenty-seven rice samples from Brazil, four parboiled brown, seventeen white and six parboiled white were analysed by ICP-MS for trace element determination. Concentrations of arsenic varied from 58.8 to 216.9?ng?g^?1, for cadmium from 6.0 to 20.2?ng?g^?1, for antimony from 0.12 to 1.28?ng?g^?1, and for uranium from 0.025 to 1.28?ng?g^?1. The estimated daily intake through rice consumption was 9.5?µg for As, 2.4?µg for Cd, 0.029?µg for Sb, 0.013?µg for U, 3.1?µg for Co, 0.2?µg for Cu, 85.6?mg for Mg, 1.9?mg for Mn, 333?mg for P, 3.0?µg for Se, 1.6?mg for Zn, 0.9?mg for Rb, and 0.3?µg for V. Found values represent a considerable percentage of the dietary reference intakes and provisional tolerable daily intake for essential and toxic elements, respectively.     

Proximate composition and selected mineral content of commercially important fish species from the black sea

Proximate composition, selected mineral (Zn, Fe, Cd, As, Hg, Pb, Ni, Cu) content and fatty acid profiles were determined in some widely consumed fish species obtained from the Black Sea. All fish species analysed individually were fairly high in protein (14·1–25·1%) and lipid (7·4–18·4%). Moisture and ash content varied within a narrow range. The mineral content was highly variable. The most abundant microelements in fish were Zn and Fe followed by Cu, and the remaining elements were present in amounts below toxic levels. Eight fatty acids (16: 0, 16:1, n-7, 18: 0, 18:1 n-9, 18: 2 n-6, 20:1 n-9, 20: 5 n-3, 22: 6 n-3) represented more than 60% of the fatty acid content. Saturated fatty acids ranged from 25·8 to 45·1%. Anchovy and whiting contained almost 35% of polyunsaturated fatty acids. The percentage of docosahexaenoic acid (DHA) exceeded that of eicosapentaenoic acid (EPA) in almost all the fish species examined, and the actual content of these acids has shown that sprat, whiting, garfish, red mullet, shad and sea bream provide the recommended daily intake of 1 g of EPA+DHA with reasonable amounts of fillet. These results indicate that biological differences existing in fish species can influence the values to be set for the standards and composition. © 1998 Society of Chemical Industry.     

Fatty acid profiles of commercially important fish species from the Mediterranean, Aegean and Black Seas

The fat content and fatty acid compositions in the flesh of eight commercially important fish species from the seas of Turkey were evaluated. The fatty acid compositions of wild fish species ranged from 25.5% to 38.7% saturated (SFA), 13.2–27.0% monounsaturated (MUFAs) and 24.8–46.4% polyunsaturated acids (PUFAs). Among them, those occurring in the highest proportions were myristic acid (C14:0, 1.70–10.9%), palmitic acid (C16:0, 15.5–20.5%), palmitoleic acid (C16:1, 2.86–17.0%), stearic acid (C18:0, 3.32–8.18%), oleic acid (C18:1n9 cis, 6.11–20.8%), linoleic acid (C18:2n6, 0.93–4.03%), octadecatetraenoic acid (C18:4n3, 0.02–4.55%), cis-5, 8, 11, 14, 17-eicosapentaenoic acid (EPA, C20:5n3, 4.74–11.7%) and cis-4, 7, 10, 13, 16, 19-docosahexaenoic acid (DHA, C22:6n3, 7.69–36.2%). The proportions of PUFAs-n3 (ranging from 21.7 for mullet to 43.7 for scad) were higher than those of PUFAs-n6 (ranging from 1.24 for bogue to 4.34 for red scorpion fish). EPA and DHA were high in all fish species, increasing the value of these fish species.     

Comparative study of trace elements in certain fish, meat and meat products

Selenium, copper, nickel, zinc, cadmium, manganese, iron, copper and lead contents of certain fish, meat and meat products consumed in Turkey were determined using inductively coupled plasma-optical emission spectrometry (ICP-OES). The order of the elements in the meat, meat products and fish samples and their concentration ranges in μg 100 g⁻¹ was Fe (57.7–156.4) > Zn (20–159) > Ni (8.2–24) > Pb (11.5–13.5) > Cr (8.44–9.51) > Cu (7.18–10.01) > Cd (0.77–1.04) > Mn (3.98–10) > Se (1.32–4.6). The elemental concentrations of fish studied seemed to be close to the international standards. The highest trace element concentrations were obtained from past?rma, meat and sausage while the lowest value was observed in Trachurus trachurus (saurel). Iron concentrations in all samples were higher than the recommended values.     

Determination of trace metal levels in sediment and five fish species from lakes in Tokat,Turkey

In this study, concentrations of trace metals in five fish species (Cyprinus carpio, Capoeta tinca, Leiciscus cephalus, Carassius gibelio and Silurus glanis) and sediments collected from some lakes in Tokat were determined by atomic absorption spectrometry. The fish species and sediment samples were collected from six lakes (Bedirkale, Boztepe, Belp?nar?, Avara, Ataköy and Ak?n) in Tokat, Turkey in spring and summer during 2003–2004. The samples were digested with a microwave digestion system. The maximum Fe, Mn, Zn, Cu, Pb, Cr and Ni concentrations of sediment samples were 2138, 232, 38.9, 8.2, 7.0, 10.7 and 55.4 μg/g, respectively. The maximum Fe, Zn, Cu, Pb, Cr, Mn and Ni concentrations of the fish samples were 167, 48.6, 3.6, 2.8, 1.6, 64.3 and 5.6 μg/g, respectively.