Levels Of Metals In Seawater Research Articles

Heavy Metals in Edible Tissue of Red Mullet from Tirana Market

High levels of heavy metals in seawater deputize a warning for public health and environment. The purpose of the study was to monitor and evaluate the concentration levels of heavy metals in edible sample tissue of Red mullet. A total of 40 of muscle sample tissue of Red mullet purchased directly from the local fresh fish market of Tirana was utilized to determine by using atomic absorption spectrophotometer (AAS). The results of the study showed that mercury (p=0.049) and lead (p0.001) concentration levels varied significantly between samples of Red mullet with different weights. According to the results concentration level of mercury and lead measured in muscle samples tissue resulted below the maximum permitted levels for human consumption set by EC legislation. High levels of cadmium made an exception (0.44 mg/kg wet weight). The results of the monitoring study give relevant information on heavy metal contamination of fish species with commercially interest such a Red mullet. The results of the monitoring process suggest that Red mullet should be object of further monitoring with the goal to protect Tirana consumer’s health from heavy metals contamination

Bioaccumulation and health risk assessment of toxic metals in red algae in Sudanese Red Sea coast

This manuscript reports the bioaccumulation levels of toxic metals by five red algae (Rhodophyta) species (Corallma, Gracilaria, Hypnea, Jania, and Laurencia) at the Sudanese coastal line of the Red Sea. The mean bioaccumulation levels (µg/g) were as follows: Cr 11.71, Mn 105.51, Ni 6.00, Cu 5.90, Zn 10.47, Cd 0.09, and Pb 1.50. The skewness values of bioaccumulation levels of all metals, with the exception of Zn, were <1, indicating symmetrical distribution in terms of species and sampling locations. The bioaccumulation levels of metals were also assessed based on species. Different affinities were recorded for each metal; e.g. Jania and Hypnea had more bioaccumulation ability of Mn and Zn than Gracilaria and Laurencia. Metal levels in seawater were quantified as well. The ranges of the concentration factors in algae and seawater samples were as follows: Cr 0.1–10, Mn 10–100, Ni 0.1–10, Cu 0.1–10, Zn 1.0–10, Cd 0.1–1.0 and Pb 0.1–10. Accordingly, significant enrichment by Mn in algae species was recorded, while no enrichment by Cd was recorded. Significant positive correlation (p < .05) was observed between the combinations of Cr–Cd, Ni–Cu, Cu–Cd, and suggesting similar accumulation behavior of those metals by Jania. Significant negative correlation (p < .05) was also observed for the Mn–Zn combination. The cluster analysis suggests that Jania and Hypnea have the most similar metal accumulation behavior than other species. The overall hazard index values were less than unity, indicating no non-cancer risk to children and adult from algae consumption. The cancer risk values for Cr, Ni, cd and Pb were within the acceptable risk level (1 × 10−6). It could be recommended to avoide Jania and Hypnea in preparing diets, food supplementary, cosmetics, and fertilizers.

Biomonitoring of metallic pollution in the coast of Jijel (Algeria) by using algological biomarkers

ABSTRACTThe paper reports the biomonitoring of metallic pollution generated by Jijel city and the port of Bouddis on the coast of Jijel (Algeria) using algological species algae [C. officinalis (Linnaeus, 1758) and Ulva lactuca (Linnaeus, 1753)] as bioindicators and biomarkers, which indicated heavy metal concentrations well above international standards (USEPA) and (IAEA-392), indicating unexpected levels of metals in seawater. The bioconcentration factor calculation has shown that these algae are excluders of Cr, accumulators of (Cu, Cd and Pb) and hyperaccumulators of Zn. These algae show different responses to toxic metals, depending on station, sampling period, age and phenological stage of specimens. These algae are suitable for use in biomonitoring for metallic pollution in coastal areas by expressing a specific range of biomarkers (MTs, GST, APX, CAT, carbonyls proteins and MDA).AbbreviationCorallina officinalis - (C. officinalis)

Cadmium uptake and zinc-cadmium antagonism in Australian tropical rock oysters: Potential solutions for oyster aquaculture enterprises

Variable and occasionally high concentrations of cadmium in wild oysters at a remote location with the potential to develop aquaculture enterprises motivated research into the distribution and sources of metals in oysters, seawater, sediment, suspended solids and phytoplankton.Saccostrea mytiloides and Saccostrea mordax contained cadmium concentrations exceeding the food standard maximum level (ML) at three of four sites. At one site with high zinc levels in sediment, oyster cadmium levels were below the ML. Metal levels in seawater were not correlated with cadmium levels in oysters but high cadmium/zinc ratios were measured in Trichodesmium erythraeum blooms.We suggest that oysters accumulate cadmium mainly from annual phytoplankton blooms except at sites where zinc availability is sufficiently high to prevent uptake though a mechanism of antagonistic exclusion. Knowledge of the source and uptake mechanisms of cadmium in oysters should lead to new management strategies to reduce cadmium levels in farmed oysters.

Study of heavy metal levels in seawater in the vicinity of Single Buoy Moorings at Mina Al Fahal, Sultanate of Oman

ABSTRACTThis study was conducted to determine the concentrations of cadmium, copper, lead, and vanadium in seawater samples taken from the vicinity of Single Buoy Mooring 3 (SBM3) at Mina Al Fahal in the Sultanate of Oman. SBM3 is one of three locations at Mina Al Fahal (SBM1 and SBM2) associated with importing and exporting refined petroleum products. Using graphite furnace atomic absorption spectrophotometry, concentrations of these four metals in seawater samples were measured in six samples. None of the metals was present in concentrations greater than the European Commission/United Kingdom Environmental Quality Standards, but a comparison to previous data collected at SBM2 indicates that concentrations have increased approximately 40% over the past two decades. To better identify sources of the metals, it is imperative to monitor effluents and collect more targeted samples at and/or near discharge points.

Measurement of environmental trace-metal levels in Mediterranean coastal areas with transplanted mussels and DGT techniques

Mussels (Mytilus galloprovincialis) and diffusive gradients in thin films (DGT) devices were deployed together for three one-month periods in coastal waters of Sardinia (Italy), in order to assess the levels of Cd, Cu, Ni, and Pb in areas differently affected by anthropogenic activities. DGT devices were more sensitive than mussels in detecting differences in metal concentrations between sites, while interpretation of the biomonitoring data revealed difficulties related to the biotic and abiotic factors that can influence the measurements. Regression analysis showed a significant correlation between Cd and Pb concentrations measured in the mussel tissues and bioavailable metal levels in seawater. Moreover transplanted mussels did not accumulate Cu and Ni following pre-exposure, although DGT showed significant concentrations of bioavailable forms of these metals in seawater. The results provided an estimate of the water quality with respect to dissolved metals and pointed out the usefulness of a combination of biomonitoring and DGT techniques for a better understanding of trace metal availability in coastal waters.

Assessment of Heavy Metal Contamination of Seawater and Marine Limpet, Patella vulgata L., from Northwest Spain

In the present work, both seawater and limpets (Patella vulgata L.) were collected from different sampling points in the Vigo estuary area (Galicia, NW Spain) and their heavy metal concentrations (Zn, Cd, Pb, Cu) were determined by means of a voltammetric technique. The results showed a direct relationship between the heavy metal levels in seawater and the content in biological samples, especially those obtained from limpet soft tissues, directly related to the increasing importance of anthropogenic environmental contamination. Heavy metal concentrations were usually higher in soft tissues than in shell, with a maximum difference corresponding to Cd and Zn (average of 93.6 and 86 folds, respectively). As expected, heavy metal content was higher in animal samples situated in inner part of the estuary zone, except for cadmium content in soft tissues, where a maximum of 5.62 ppm was quantified in limpet soft tissues collected next to the open sea area. Statistical analysis allowed the establishment of a clear relationship between Zn and Cd content in both shells and soft tissues from limpet, and especially between Zn and Cu in soft tissues (p<0.001).

Effects of heavy metals on the respiratory proteins of marine organisms in relation to environmental pollution.

Seawater is a fluid medium containing measurable concentrations of many heavy metals that are potentially toxic to organisms. From the diversity of species and the complexity of life histories of marine animals, it is obvious that biochemical, physiological and behavioral adaptations have evolved to allow these animals to exist in what is a potentially toxic environment. In marine organisms the pathological effects of heavy metals have only been observed at locations where the activities of man have significantly increased the concentrations of heavy metals in the marine environment and in laboratory systems where animals have been isolated and subjected to increased levels of metals in seawater or in their diet. In unstressed or unpolluted areas, marine organisms have evolved the capability to deal with the fluctuations of metal availability in the environment. Adaptation to metal pollution sometimes occurs if the change to higher metal concentrations takes place slowly. A better understanding of the detoxification process utilized in normal and metal-stressed environments is necessary for proper interpretation of the consequences to man’s health of using metal-dosed organisms as part of the food supply.

Use of the mussel Mytilus edulis planulatus (Lamarck) in monitoring heavy metal levels in seawater

The accumulation of cadmium, copper; lead and zinc in tissues of M.e.planulatus was examined at a number of metal concentrations in seawater. In every case, a linear relationship was found, in some cases after exposure to the metal for up to 86 days. The relationship between rate of accumulation of a metal over a 40- day period and its concentration in seawater was determined for each metal. From the results of field trials, it was concluded that the rate of accumulation could be used as a sensitive method of estimating concentrations of metals in seawater, with greater convenience than methods involving direct analysis. A monitoring program, in which M.e. planulatus is used to quantify levels of heavy metals in seawater; is proposed with certain limitations. The effects of extraneous parameters, both biological and physicochemical, on the accumulation of the metals were examined in relation to the ways in which they might limit the usefulness of this mussel in such a monitoring program.