Tissue Pb Concentrations Research Articles

Lead poisoning and its in vivo biomarkers in Mallard and Coot from two hunting activity areas in Poland

In this study, we aimed to present the status of lead (Pb) poisoning in birds from southern Poland and the evaluation of in vivo biomarkers which may be used in the diagnosis without killing animals. This included the activity of δ-aminolevulinic acid dehydratase (ALA-d), hemoglobin (Hb) concentration, hematocrit (Ht) level and concentrations of Pb in blood, feathers and excrements. The significance of this work is the use of hunted birds which allow us to compare the signals of the chosen biomarkers with the internal response. Birds collected in the area of lower hunting activity (the Milicz ponds) revealed statistically lower Pb concentrations than birds from the Zator area. Pb poisoning was diagnosed in almost 8% of birds (including specimens from both areas), but lead pellets were found in 3%. The highest tissue concentration found was noted in kidneys of Mallard from the Zator area (36.55 μg g(-1) d.w.). Significantly higher concentrations were noted in a few samples of gizzard content (up to 1047 μg g(-1) d.w.) and excrements (up to 82.95 μg g(-1) d.w.). Hb concentration, Ht level, concentrations in feathers and excrements seem not to be efficient biomarkers at noted Pb concentrations in internal tissues (brain, pectoral muscle, kidney, liver, spleen, bone). In contrast, we found a significant negative correlation between Pb concentration in blood and ALA-d activity which confirmed that this parameter can be used successfully as in vivo biomarker of lead poisoning also in low environmental pollution.

Tissue-specific Cd and Pb accumulation in Peruvian scallop (Argopecten purpuratus) transplanted to a suspended and bottom culture at Sechura Bay, Peru

In order to understand the effect of different culture systems on Cd and Pb accumulation, suspended long-line and bottom cultures of Argopecten purpuratus were conducted during January until April 2010 (120 days). The Cd tissue levels were the highest at the middle of the experiment (30-d till 70-d) for suspended-cultured individuals, while bottom-cultured individuals showed an increasing trend. Gonad Pb levels were also higher during the same period for all cultures, while adductor muscle exhibited no considerable variations. Cd and Pb tissue concentrations were mainly greater in deeper cultures. There were no significant differences in Cd and Pb accumulation between individual sizes. The Cd and Pb levels in edible tissue (gonad+adductor muscle) did not exceed the EU and FDA maximum levels. Based on the target hazard quotient (THQ) and the provisional tolerance weekly intake (PTWI), no risk (THQ<1 and %PTWI<30) was found for human consumption.

Heavy metal translocation and accumulation in iron plaques and plant tissues for 32 hybrid rice (Oryza sativa L.) cultivars

Rice (Oryza sativa L.) planted on heavy metal contaminated soil is a source of toxic elements entering the food chain and thereby posing a threat to human health. The main objective of this study was to investigate heavy metals uptake, translocation, and accumulation differences in iron plaque and rice tissues among the rice cultivars. In the present study, 32 hybrid rice cultivars were cultured on heavy metal contaminated paddy soil. Pb, Cd, Cu, and Zn concentrations in rice tissues (root, straw, husk, and brown rice) and in the iron plaques on rice root surfaces were measured. Significant differences of Pb, Cd, Cu, and Zn tolerance, concentrations and accumulation in 32 rice cultivars were observed. However, no significant difference was observed in concentrations of Pb, Cd, Cu, and Zn in two-line hybrid rice and three-line hybrid rice. The concentrations of Pb in iron plaques were significantly positive linearly correlated with concentrations of Pb in rice roots, and concentrations of Cd and Cu were significantly negative linearly correlated with Cd and Cu in rice roots. The concentrations of heavy metal in brown rice were significantly positively correlated with the translocation factors TFhb (from husk to brown rice) and TFsh (from straw to husk). It indicated that iron plaque plays an important role in mediating heavy metal entering into rice roots, and heavy metal accumulation in brown rice was related to its ability to transfer in the husk and straw rather than the root.

Effects of Phosphate Fertilizers on Bioavailable Lead in Tea Garden Soil and Lead Absorption and Accumulation by Tea Plants

Tea is a widely consumed beverage in the world and an important economic crop in China. However in recent years tea gardens were increasingly contaminated by heavy metals such as lead (Pb). Root uptake of Pb could contribute significantly to Pb accumulation in tea leaves due to the strong acidity of tea garden soils. To reduce the Pb bioavailability and absorption by tea plants, a pot experiment was conducted to evaluate the effects of 3 phosphate fertilizers separately with a normal application rate in the field of 0.2 g (P2O5) ·kg-1soil and a high application rate of 0.5 g (P2O5) ·kg-1soil on bioavailable Pb in tea garden soil and Pb absorption and accumulation by tea plants. Results showed that application of calcium magnesium phosphate significantly increased soil pH by up to 0.6 units from 3.50 to 4.13. Phosphate fertilizers resulted in an increase of bioavailable Pb concentration in tea garden soil under our experimental conditions. Pb concentration in tissues of the tea plants under different phosphate fertilizer treatments followed the order of root&gt;stem&gt;leaf. Calcium magnesium phosphate with a high application rate of 0.5 g P2O5·kg-1soil decreased Pb concentrations of roots, stems and leaves of tea plants significantly. For one phosphate fertilizer, Pb absorption in tea plants under high application rate was much lower than it under normal application.

Histopathology related to cadmium and lead bioaccumulation in chronically exposed wood mice, Apodemus sylvaticus, around a former smelter

The ceasing of industrial activities often reduces the emission of pollutants but also often leaves disturbed areas without remediation and with persistent pollutants that can still be transferred along the food chain. This study examines the potential relationships between non-essential trace metals and histopathology in target tissues of wood mice (Apodemus sylvaticus) collected along a gradient of contamination around the former smelter, Metaleurop Nord (northern France). Cadmium and lead concentrations were measured, and histological alterations attributable to chronic trace metal exposure were assessed in the liver and the kidneys of 78 individuals. Metal concentrations quantified in the present study were among the highest observed for this species. Some histological alterations significantly increased with Cd or Pb concentrations in the soil and in the organs. Sixteen mice from polluted sites were considered at risk for metal-induced stress because their Cd and/or Pb tissue concentrations exceeded the LOAELs for single exposure to these elements. These mice also exhibited a higher severity of histological alterations in their organs than individuals with lower metal burdens. These results indicate that the Metaleurop smelter, despite its closure in 2003, still represents a threat to the local ecosystem because of the high levels and high bioavailability of Cd and Pb in the soil. However, among the mice not considered at risk for metal-induced stress based on the metal levels in their tissues, a large percentage of individuals still exhibited histological alterations. Thus, the present study suggests that the evaluation of toxic effects based only on the LOAELs for single metal exposure may result in the underestimation of the real risks when specimens are exposed to multiple stressors.

Is the tapeworm able to affect tissue Pb-concentrations in white rat?

The effect of gastrointestinal helminths on Pb accumulation in the host body is ambiguous. A laboratory experiment with Rattus norvegicus/Hymenolepis diminuta model was conducted to determine Pb toxicokinetics in a terrestrial host-parasite system. The ET-AAS or ICP-OES techniques were used to determine Pb concentrations (CPb) in both tapeworms and host tissues (kidney, liver, bone, testes, muscle and intestinal wall). Concerning the entire host-parasite system, the highest CPb were detected in H. diminuta. Rat kidneys and bone were the only two tissues whose mean Pb levels were lower in parasitized animals than they were in non-infected subjects after both levels of exposure. At low Pb exposure, parasitization slightly changed the Pb toxicokinetics in the host body. However, with respect to tissue at the same exposure level, no significant differences were detected between the parasitized and non-parasitized animals and no significant correlations were found between CPb in tapeworms and those of host tissues. The results of this study indicate that H. diminuta does not protect rat from elevated Pb exposure even if tapeworm accumulates a higher portion of ingested Pb dose compared with that of the most Pb-loaded host soft tissue. The portion of Pb dose accumulated in H. diminuta correlates positively with parasite biomass.

Heavy metals concentration in oyster Crassostrea sp. HZ, sediment and sea water, Musa estuary

Heavy metals are permanent pollutants that are able to accumulate in the tissues of marine organisms. Toxicity and bioaccumulation of heavy metals in aquatic organisms have been considered as a critical problem. New species oyster Crassostrea sp.HZ, that live near petrochemical complex in the Musa estuary, especially may be exposed to considerable amounts of heavy metals from surrounded environment. The primary goal of this study investigates the concentration of Cd, Cu, Zn and Pb in recently reported oyster Crassostrea sp.HZ and its habitat in Musa estuary. Oyster, sediment and sea water samples were obtained from six selected stations. The soft tissue of oysters was separated. All of the samples were acid digested and their heavy metals level were analyzed using atomic absorption spectrometer. The concentration of Cd, Cu, Zn and Pb in soft tissues ranged 12.21-17.5, 207.2-403.52, 90.43-104.12 and 0.07-0.95 (µg/g), respectively. The concentrations of the same metals in sediment were 0.15-0.85, 1.99-141.42, 60.42-122.1 and 2- 7.2 (µg/g) respectively. The concentrations of heavy metal in sea water was ND- 0.7, ND-3.1, 9.12- 23.03 and 0.15-2.27 (µg/g), respectively. The result showed that the level of heavy metals in soft tissue of C. sp.HZ was higher than general standard. * Corresponding Author: A. Safahieh  a.safahieh@kmsu.ac.ir

Bioaccumulation of Heavy Metals in Fish Sourced from Environmentally Stressed Axis of River Niger: Threat to Ecosystem and Public Health

Pollution of freshwater ecosystems is alarmingly becoming high in Nigeria with attendant public health effects on the dependent populations. Fish, a source of protein with pronounced placement on local food menu is now considered an important dietary threat of heavy metal toxicity via consumptions. Bioaccumulation of heavy metals (copper, zinc and lead) in Silver catfish (Schilbe intermedius) from River Niger was conducted. The Fish samples were collected from different sites of Onitsha axis of the River Niger owing to their environmental stresses. Samples were analyzed for heavy metal (copper- Cu, zinc- Zn, and lead- Pb) concentrations in muscle tissues using the Atomic Absorption Spectrophotometer (AAS) and compared with Food and Agriculture Organization safe limits. Margin of exposure (MOE) was estimated to measure the potential public health risk of consuming the contaminated fish. The concentrations of heavy metals (Cu- 8.92±4.748, Zn- 0.36±0.249, and Pb- 2.689±1.505) observed were significant (P Pb>Zn. Statistical Pearson moment correlation analysis showed that the concentrations of heavy metals detected were independent of the weight of sampled fish for zinc but was positively correlated for copper and lead. Relating the mean metal concentrations obtained in the study with Food and Agriculture Organization standard for fish muscles indicated that mean concentrations of copper, zinc and lead are far above safe margins for human consumption except the fish sourced from sites A4 and A9 for lead and zinc, respectively. Margin of exposure was below one and tentatively considered not to be of risk to public health. However, there is considerable contamination of the Silver catfish from the River Niger with heavy metals. It is recommended that substantial attention be paid to the heavy metal levels in freshwater fishes from the river. Measures should be put in place to regulate the indiscriminate dredging activities, discharge of raw sewage and industrial effluent into the river and regular public health check on the level of heavy metals among the populace in the communities that border the area should be employed.

Effect of El-Sail Drain Wastewater on Nile Tilapia (Oreochromis niloticus)from River Nile at Aswan, Egypt

This study demonstrates the impact of wastewater of El-Sail Drain on the health of Oreochromis niloticus collected from two sites of River Nile at Aswan Governorate. One of these sites is before (I) and the other is after (II) the disposal point of El-Sail drain. The physicochemical parameters of water (pH, electric conductivity, total dissolved solids, dissolved oxygen, biological and chemical oxygen demands, nitrite, nitrate and ammonia) were determined. Heavy metals (Cu, Pb, Cd and Ni) concentrations in water and fish tissues (gills, muscles, liver and gonads) were detected. The microbiological, parasitological and pathological conditions of fish were also investigated. Higher values of pH, EC, BOD and COD were detected in site II than from site I. In contrast to DO, nitrite, nitrate and ammonia which were lower in site II. Heavy metals concentrations in water of both sites, especially Ni, Pb and Cd exceeded the permissible limits and its abundance followed the order: Pb>Ni>Cd>Cu. Total bacterial count, total coliform, Salmonella sp., Shigella sp. and E. coli were detected in higher numbers in water samples from site II. Moreover, the fish caught from that site revealed higher bacterial and parasitic infection. The bioaccumulation of Ni and Pb exceeded the maximum permissible limit; however, Cu and Cd concentrations were below the permissible limit in different tissues. The bioaccumulation factor of Cu showed its highest value in liver. The histopathological lesions were more prominent in fish collected from site II. So, consuming fish caught from the studied sites around El-sail drain disposal point represents serious hazard on human health.

Comparative study of the bioaccumulation and elimination of trace metals (Cd, Pb, Zn, Mn and Fe) in the digestive gland, gills and muscle of bivalve Pinna nobilis during a field transplant experiment

The purpose of this study was to investigate the long-term bioaccumulation and elimination of Cd, Pb, Mn, Zn and Fe by Pinna nobilis tissues after their 90 day-transplantation period at Téboulba fishing harbor. During the transplantation period, the Cd, Pb, Mn, Zn and Fe concentrations in the different tissues of the mussels were measured before and after exposure period. Metal (Cd, Pb, Mn, Zn and Fe) accumulation in P. nobilis mussels varied depending on the analyzed tissue and the caging times. Notable differences in Cd, Pb, Mn, Zn and Fe accumulation patterns within the digestive gland, gills and muscle were found and may be due to the ability of each tissue to accumulate metals. During the depuration phase, the elimination of Cd, Pb, Mn, Zn and Fe depended on the target tissue and the metal speciation. Cd, Pb, Mn and Fe were eliminated rapidly from one organ and increased in other when compared to those of 90 day transplanted mussels. The increase of metal loads during the elimination phase is not clear and particularly what kind of processes is responsible for such response. However, it is reasonable to assume that metals increase is related to the existence of an accumulation/detoxification mechanism, which involves the transport of metals from an organ to another. The data obtained indicate that because of the significantly high quantities of Cd, Pb, Mn, Zn and Fe accumulated during the exposure phase, the transplanted mussels are suitable bioindicators for monitoring trace metals in marine ecosystem.

Accumulation of metals in weed species grown on the soil contaminated with industrial waste and their phytoremediation potential

a b s t r a c t Phytoremediation is an eco-friendly, economically feasible and emerging technique for the restoration of environment contaminated with heavy metals. Present study was conducted to determine the heavy metal accumulation potential of twelve native weed species viz. Calotropis procera, Croton bonplandianum, Cyperus rotundus, Datura stramonium, Euphorbia hirta, Parthenium hysterophorus, Phyllanthus amarus, Sida cordifolia, Solanum nigrum, Solanum xanthocarpum, Spinacia oleracea and Tridax procumbens growing nat- urally in the field at Lucknow UP, India. Heterogeneous accumulation of metals was found among the different weeds. Moreover, metal accumulation varied within the plant tissues i.e. roots and shoots. The concentration of Cr, Cu, Ni, Pb and Cd in the root tissues were found in the range of 3.97-67.72, 3.44-45.47, 2.52-14.19, 6.13-58.28 and 0.32-3.96 g g−1 whereas the corresponding shoot values were 5.45-125.67, 2.87-19.60, 1.81-15.39, 5.18-44.28 and 0.23-3.17 g g −1 respectively. Among the different plant species the translocation factor (TF) ranged between 0.453-1.938, 0.136-3.236, 0.346-2.065, 0.277-3.857 and 0.119-3.314 for Cr, Cu, Ni, Pb and Cd respectively. All the plants were found to have an enrichment coef- ficient of >1, which reflects their high metal accumulation potential. Findings suggest that studied weed species may be used for the phytoremediation and restoration of land contaminated toxic metals.

Determination of Heavy Metal (Zn, Pb, Cd and Cr) Concentration in Benthic Fauna Tissues Collected from the Southeast Caspian Sea, Iran

The aim of the present study was to determine zinc (Zn), chromium (Cr), cadmium (Cd) and lead (Pb) content of benthic fauna in the southeast coast of the Caspian Sea, where the major fish restocking programs are conducted. Seasonal sampling was performed in three sampling sites: north Miankaleh (NM), south Miankaleh (SM) and Gharesoo coast (GC). Results showed that sampling sites, sampling seasons and sampling sites × sampling seasons interaction had a significant effect on the heavy metal levels (p < 0.05). The yearly heavy metal concentration order was as follows: Zn > Pb > Cd > Cr. Yearly Pb levels of the NM site were significantly higher than the other sites. Also, yearly Cr levels of the SM site were significantly higher than site GC. Comparison of the benthos heavy metal levels with the available reference values suggests that the benthos tissues might be highly polluted which can intoxicate the fish feeding on them.

Age-dependent accumulation of heavy metals in liver, kidney and lung tissues of homing pigeons in Beijing, China

Biomonitoring provides direct evidence of the bioavailability and accumulation of toxic elements in the environment. In the current study, 1-2, 5-6, and 9-10+ year old homing pigeons collected from the Haidian District of Beijing during 2011 were necropsied and concentrations of cadmium, lead, and mercury were measured in liver, lung, and kidney tissue. At necropsy, gray/black discoloration of the margins of the lungs was observed in 98 % of the pigeons. There were no significant differences in metal concentrations as a function of gender. Cadmium concentrations in all tissues and Pb concentrations in the lung tissues were significantly greater in 9-10+ year old pigeons compared to other age groups indicating that Cd and Pb were bioavailable. Mercury concentrations were not significantly different among age groups. Cadmium concentrations in kidney and lung tissues of 9-10+ year old pigeons were similar to or exceeded concentrations of Cd reported in pigeons from another high traffic urban area and most wild avian species from Korea suggesting that Cd in this region of Beijing may be of concern. Homing pigeons provide valuable exposure and bioaccumulation data not readily available from air monitoring alone, thus providing information regarding potential health effects in wildlife and humans in urban areas. As environmental quality standards are implemented in China, homing pigeons will serve as a valuable bio-monitor of the efficacy of these actions.

Field and laboratory assessments on dissolution and fractionation of Pb from spent and unspent shots in the rhizosphere soil

The objective of this study was to determine the effect of plant root growth on Pb dissolution from shot under laboratory and field-scale conditions. For a laboratory study, a 100-d incubation experiment was conducted to assess Pb dissolution from unspent shot (new) and spent shot (>10yr in fields) in rhizosphere and non-rhizosphere (bulk) soils using the Toxicity Characteristic Leaching Procedure (TCLP) and sequential extraction methods. This study found that increasing the soil pH value to 7.5 by liming significantly reduced Pb dissolution from unspent and spent shot (<5mgL(-1)). Dissolution of Pb from shot was induced more in rhizosphere than bulk soils. Regardless of shot types, the averaged TCLP-Pb concentration in acidic and limed soils was 12.9- and 8.1-fold greater in rhizosphere than in bulk soils, respectively. For a field-scale investigation, a total of 31 individual plant samples of 6 different species and their rhizosphere soils were collected from a clay-target shooting range (<35000mgPbkg(-1)). The Pb concentration in plant aboveground tissues depended on species with a mean value of 72mgkg(-1) (15-254mgkg(-1)), which was far smaller than that reported in previous studies. Regardless of high soil Pb levels, aboveground tissue Pb concentrations of Solidago altissima (i.e., Canada goldenrod, 15mgkg(-1)) and Andropogon virginicus (i.e., broomsedge, 18mgkg(-1)) were below the toxicity threshold, suggesting that these indigenous species could have phytostabilization potentials. The limited Pb accumulation by vegetation was attributed to the abundance of soil calcite derived from spent clay-target fragments.

The effect of lead exposure on tracheal responsiveness to methacholine and ovalbumin, total and differential white blood cells count, and serum levels of immunoglobulin E, histamine, and cytokines in guinea pigs

The effect of exposure to inhaled lead acetate in guinea pigs was evaluated. The present study comprised of five groups of guinea pigs including control (C), sensitized to ovalbumin (OA; S) and three groups exposed to 0.1, 0.2, and 0.4 M inhaled lead (Pb; n = 6 for each group). Tracheal responsiveness to methacholine and OA, total and differential white blood cells (WBCs) count in lung lavage, serum levels of cytokines (interferon γ (IFN-γ) and interleukin 4 (IL-4)), histamines, and immunoglobulin E (IgE), and Pb concentration in lung were measured. Tracheal responsiveness to methacholine, OA, total and differential WBC types as well as IL-4, IFN-γ, histamine, and IgE were significantly increased but IFN-γ/IL-4 were significantly decreased in sensitized animals as well as those exposed to high Pb concentrations when compared with the control group (from p < 0.05 to p < 0.001). In addition, there was not a significant difference in most measured values between animals exposed to high Pb concentration and group S. The Pb concentration in lung tissues of animals exposed to all three Pb concentrations was significantly higher than that of group C (p < 0.001 for all cases).These results showed that inhaled lead acetate exposure can induce lung inflammatory changes similar to sensitized animals. Therefore, exposure to environmental Pb pollution may cause asthma-like changes.

Toxic Exposure of Songbirds to Lead in the Southeast Missouri Lead Mining District

Mining and smelting in the Southeast Missouri Lead Mining District has caused widespread contamination of soils with lead (Pb) and other metals. Soils from three study sites sampled in the district contained from approximately 1,000-3,200 mg Pb/kg. Analyses of earthworms [33-4,600 mg Pb/kg dry weight (dw)] collected in the district showed likely high Pb exposure of songbirds preying on soil organisms. Mean tissue Pb concentrations in songbirds collected from the contaminated sites were greater (p < 0.05) than those in songbirds from reference sites by factors of 8 in blood, 13 in liver, and 23 in kidney. Ranges of Pb concentrations in livers (mg Pb/kg dw) were as follows: northern cardinal (Cardinalis cardinalis) = 0.11-3.0 (reference) and 1.3-30 (contaminated) and American robin (Turdus migratorius) = 0.43-8.5 (reference) and 7.6-72 (contaminated). Of 34 adult and juvenile songbirds collected from contaminated sites, 11 (32%) had hepatic Pb concentrations that were consistent with adverse physiological effects, 3 (9%) with systemic toxic effects, and 4 (12%) with life-threatening toxic effects. Acid-fast renal intranuclear inclusion bodies, which are indicative of Pb poisoning, were detected in kidneys of two robins that had the greatest renal Pb concentrations (952 and 1,030 mg/kg dw). Mean activity of the enzyme delta-aminolevulinic acid dehydratase (ALAD) in red blood cells, a well-established bioindicator of Pb poisoning in birds, was decreased by 58-82% in songbirds from the mining sites. We conclude that habitats within the mining district with soil Pb concentrations of ≥1,000 mg Pb/kg are contaminated to the extent that they are exposing ground-feeding songbirds to toxic concentrations of Pb.

Tissue Distribution of Metals in White-fronted Geese and Spot-Billed Ducks from Korea

This study presents concentrations of Fe, Zn, Mn, Cu, Pb and Cd in livers, kidneys, muscles and bones of white-fronted geese Anser albifrons (geese) and spot-billed ducks Anas poecilorhyncha (ducks). Iron in livers, kidneys and muscles, Zn in muscles, Mn and Cd in every tissue, Cu in livers, muscles and bones and Pb in bones differed between species, and there were significant differences among tissues in both species. Essential elements such as Fe, Zn, Mn and Cu concentrations were within the background levels. Lead concentrations in livers of 7 of 14 geese and 7 of 19 ducks and in bones of 4 of 19 ducks exceeded background concentrations for waterfowl (5μg/g dw for the liver, 10μg/g dw for the bone). Almost all samples of both species had the background Cd concentrations in the liver (33 of 33 geese and ducks) and kidney (14 geese and 18 ducks). Tissue concentrations of Cd were greater in geese than ducks. In contrast, tissue concentrations of Pb in bones were greater in ducks than in geese. These different trends for Cd and Pb reflect a short and/or long term difference in exposure and degree of accumulation of these metals.

Use of sedimentary metals to predict metal concentrations in black mussel (Mytilus galloprovincialis) tissue and risk to human health (Sydney estuary, Australia)

Filter-feeding bivalves have been used extensively as an indicator of ecosystem condition and in management of estuarine environments. The current study aimed to determine whether sedimentary metals could predict metal concentrations in tissue of filter-feeding mussels (Mytilus galloprovincialis) and to identify areas of the estuary where mussel consumption posed a human health risk. Mussel tissue Cu and Zn concentrations (wet weight) were below guideline values for human consumption in all parts of the waterway, whereas Pb tissue concentrations exceed these guidelines (2.0 μg g(-1) wet weight) in the upper reaches of some embayments of the estuary. Concentrations of Cu and Pb in the fine fraction (<62.5 μm) of bottom sediment reasonably predicted concentrations (dry weight) of these metals in mussel tissue (r (2) =0.460 and p=0.001 and r (2) =0.669 and p<0.0001, respectively) as these materials are resuspendable and available to filter-feeding estuarine animals, whereas total sediment and mussel tissue were poorly related. Lead concentrations (>350 μg g(-1)) in fine sediments indicated areas of this estuary where human health was at risk due to high tissue concentrations of this metal. These results give encouragement for the use of the metal concentration in fine sediments as an indicator of estuarine condition and risk to human health in this waterway. Mussels were distributed in all parts of the estuary, even in areas where metal concentrations exceeded sediment quality guidelines.

Metal concentrations and pathological responses of wild native fish exposed to sewage discharge in a Mediterranean river

The requirements of the Water Framework Directive suggest the need for further research to test and develop sensitive tools that will allow freshwater managers to detect impacts on fish communities. Diagnostic refinement often encompasses the use of lethal diagnostic tools that are incompatible with the conservation of native ichthyofauna. Here we determine the metal concentration and the pathological response of Squalius laietanus exposed to sewage discharges in the Ripoll river (north-eastern Spain), and compare these findings with our previous studies on Barbus meridionalis using lethal and non-lethal diagnostic tools. Metals concentrations (Zn, Cu, Pb, Hg, Fe, Cd and Ni) were determined in liver and muscle. A complete blood cell profile (haematocrit, haemoglobin, differential leukocyte count, erythrocytic nuclear abnormalities, erythrocytes in division and the development stage of erythrocytes) was used as a non-lethal diagnostic tool to determine early warning signs of disease in these two fish species. As the reference range for these haematological variables is lacking, liver histology, calculation of body condition (CF) and organosomatic indices (HSI and GSI) were employed to support the findings of the blood analyses. Compared to our previous results on B. meridionalis, S. laietanus appeared to have fewer pathological responses than B. meridionalis under the environmental conditions measured and the fish size range examined in this study. Both species showed a similar bioaccumulation pattern, but B. meridionalis stored high Hg and Cu concentrations in muscle and liver, respectively. Hg, Cu and Pb concentrations in fish tissues exceeded the thresholds of European and Spanish legislation. Our findings pinpoint the potential suitability of the blood variables determined in the health diagnoses of these species. Further research will be necessary to establish the natural variability of these and other haematological variables to convert haematology into a sensitive and useful non-lethal diagnostic tool in wild fish populations.

Essential and toxic elements in meat of wild and bred animals

Essential and toxic elements were determined by Energy Dispersive Polarized X-Rays Fluorescence Spectrometry (EDPXRF) in the meat of 145 wild and bred animals to provide the baseline data regarding meat of wild and bred animals consumed in central Italy. As far as K, Fe, Ni, Zn, and Cu are concerned, no significant differences resulted between young and adults and between males and females for farmed and wild animals. No marked differences were found between hunted and non-hunted animals groups. In all samples analyzed, Mn, Cr, and Mo were below the detection limit. As far as the non-essential or toxic elements are concerned, As, Cd, V, and Hg concentrations in muscle from wild and bred animals were low and always below the detection limits. Among the wild animals killed with lead (Pb) bullets, elevated Pb concentrations in tissues were detected. This finding may result in elevated Pb levels in meat ingested by humans.