Bioaccumulation Of Zn Research Articles

Bioaccumulation of Cd, Cu, Pb, and Zn in Oyster (Saccostrea cucullata) from Qeshm Island Coast in Persian Gulf: Implications of Provisional Maximum Tolerable Daily Intake (PMTDI)

Concentrations of heavy metals (Cd, Cu, Pb, and Zn) were determined in soft tissue of 122 rock oyster (Saccostrea cucullata) collected at seven stations from the coastal zones of Qeshm Island. The exposure of the consumer is compared directly to maximum residue level and provisional maximum tolerable daily intake. Result indicated that levels of Cd, Pb, and Cu were within limits, but the level of Zn exceeded that the limit. Concentrations of Zn (1168.71 μg g−1) and Cu (105.16 μg g−1) were comparatively higher than the level recommended in the international food standards, such as Brazilian Ministry of Health, National Health Medical Research Council, Ministry of Agriculture, Fisheries and Food, and the Tasmania Public Health Regulation. The results, therefore, indicate possible risk in consuming the oysters.

Inter-site differences of zinc susceptibility of the oyster Crassostrea hongkongensis

Understanding the underlying mechanisms governing metal toxicity is crucial for predicting the risks and effects of metal pollutants. We hypothesized that metal toxicity is related to a threshold concentration of metabolically available metal but not to the total body metal concentration. Following a two-month laboratory Zn exposure, we characterized mortality and Zn bioaccumulation and subcellular partitioning in the oyster Crassostrea hongkongensis sampled from three sites with contrasting histories of Zn exposure and one multiple-metal contaminated site. Large differences in Zn sensitivity, lethal body concentration, and detoxification capability between sites were observed. Specifically, the oysters from the highly Zn-contaminated site were more tolerant to Zn exposure than those from the relatively clean ones, and the former accumulated and detoxified more Zn and had a significantly higher lethal body Zn concentration. The accumulation of Zn in the metabolically available pool (operationally defined as the metal-sensitive fraction) in the oysters from the multiple-metal contaminated site was relatively fast, and correspondingly they were highly sensitive to Zn exposure. The lethal threshold concentration of total body Zn varied significantly within the four sites, and thus total body Zn concentration could not serve as a suitable toxicity indicator. Importantly, Zn accumulation within the operationally defined metabolically available pool better explained variances in mortality than Zn accumulation in the whole body. Our results suggested that Zn toxicity is governed by its accumulation in the metabolically available pool, not the total accumulated Zn concentration.

Histopathology of cerebro neuronal cells in freshwater snail Bellamya bengalensis: impact on respiratory physiology, by acute poisoning of mercuric and zinc chloride

Mercuric (Hg) and zinc (Zn) chloride toxicity was investigated in cerebroneuronal cells and gills of Bellamya bengalensis using sublethal concentrations under lab conditions. Freshwater snail B. bengalensis was exposed to mean LC50 concentration (1.56 ppm and 12.7 ppm) of Hg and Zn chloride, respectively. Bioaccumulation of Hg and Zn was observed in nervous and gill tissue in proportion to the time of exposure. Respiratory mechanisms and rate of oxygen consumption was depleted by both metals. Histopathological alterations in cerebro neuronal cells (giant, large, medium, and small) and gill filamental epithelia were apparent in Hg and Zn-exposed snails. Histopathology demonstrated increased cytoplasmic basophilia, extreme indentation of plasma membrane, karyolitic and eccentric nuclei, nuclear envelope with irregular size, and shrunken appearance of cerebroneuronal cells. Histologically, gill filamental epithelia showed hypertrophy, enlarged ciliated margins reduced length of cilia, nuclear dilations, thickening of basal lamina, and hemocytic accumulations in induced cells and severe loss of goblet mucus cells at the tip. Histopathology was accompanied by dysfunctioning cilia with decreased rate of respiration. Overall, neuronal impairment with damaged gill filament produced improper gaseous exchange leading to sluggish movement.

Bioaccumulation of Pb, Ni and Zn in Some Plant Species Growing In and Around a Municipal Waste Dumpsite at Allahabad, India

Bioaccumulation of Pb, Ni and Zn in Some Plant Species Growing In and Around a Municipal Waste Dumpsite at Allahabad, India

Accumulation and transfer of Hg, As, Se, and other metals in the sediment-vegetation-crab-human food chain in the coastal zone of the northern Brazilian state of Pará (Amazonia)

The high consumption of crabs (Ucides cordatus) stimulated interest in the present study on the northern coast of Brazil, which encompasses a preserved area of mangrove forest. The objective was to describe and quantify the transfer of metals from the muddy sediments to the leaves of the Rhizophora mangle, and thence the crabs and humans. The samples were collected along two transects, while samples of hair were obtained from local habitants. The pH, interstitial salinity, Eh (mV) were measured, the granulometry and mineralogical and multi-element chemical analyses were run, and the organic material determined. The sediments are silty-clayey, composed of quartz, kaolinite, iron oxides, and illite, as well as smaller portions of smectite, pyrite, halite, and high levels of SiO2 (56.5%), Al2O3 (18.5%), and Fe2O3 (7%). The elements Zn, Sr, As, and Zr are concentrated in the leaves, while the bioaccumulation of Zn, Se, Sr, and As was recorded in the crabs, of which, Se is the most concentrated in the tissue of the muscles and the hepatopancreas. The concentrations of nutrient and toxic elements were similar in all age groups (hair samples), with only Hg presenting an increasing concentration between infants and adults. The highest rates of transfer were recorded for the elements Zn and Se in the crabs and Hg in leaves and hair. The accumulation of metals in the leaves and crabs reflects the chemical composition of the sediments and low rates of sediment-vegetation-crab transfer, with the exception of Hg, which accumulated in the hair.

Changes in growth and biochemical status of common carp, Cyprinus carpio L. exposed to water-born zinc toxicity for different periods

The present study was carried out to investigate the effect of sublethal zinc (Zn) concentrations on the growth, biochemical variables, and Zn residues in common carp, Cyprinus carpio L.. Fish (18.1 – 19.1 g) were exposed to 0.0 (control), 5.0 and 10.0 mg Zn/L for 7, 14, 28, and 56 days. At each time interval and each treatment, fish were collected, weighed and sampled to measure the growth, biochemical variables, and Zn residues in whole-fish body. Growth performance was significantly reduced with increasing Zn concentrations. However, fish exposed to 10.0 mg Zn/L for 56 days grew lower than that of the control group. Likewise, the optimum feed intake and feed conversion ratio were obtained at control group at 56 days. Furthermore, glucose, AST, ALT, creatinine, and cortisol increased significantly with increasing Zn concentration and exposure time, with maximal values at 56 days. Meanwhile, the highest values of serum protein and lipids of were obtained in the control fish reared for 56 days, whereas the lowest values were observed in fish exposed to 10.0 mg Zn/L for 56 days. The content of whole-body moisture and total ash increased significantly, while crude protein and total lipid contents decreased significantly with increasing Zn concentrations. In addition, Zn exposure increased Zn residues in fish body; however, Zn bioaccumulation in fish body was Zn dose and time dependant. The present study revealed that the growth and health status of common carp were deteriorated by Zn toxicity.

Dynamics Phytoremediation of Zn and Diesel Fuel in Co-contaminated Soil using Biowastes

In phytoremediation of co-contaminated soil, developing strategies is a major challenge for simultaneous and efficient remediation of multiple pollutants. A lab-scale experiment was set up to investigate the efficiency of adding 5% (w/w) individually of three different organic waste amendments [tea leaves, soycake and potato skin] to enhance the phytoaccumulation of Zinc and diesel fuel co-contaminated soil by Dracaena reflexa for a period of 180 days. Soil contaminated with Zn (80 mg kg-1DW) was spiked with an initial concentration of diesel fuel (25000 mg kg-1DW). Application of biowastes demonstrates significant degradation of DF compared to control soil. The highest rate of oil degradation was recorded in co-contaminated soil planted with D. reflexa and amended with SC (85%) followed by PS and TL (60 and 53.3%). Although the plants did not accumulate any hydrocarbon from the contaminated soil but there was significant bioaccumulation of Zn in the root and stem of Dracaena plant which was observed. At the end of 180 days, 16.5 mg/kg and 12.2 mg/kg of Zn in the root and the steam of D. reflexa was recorded. Results indicated that the D. reflexa could effectively extract Zn from Zn-contaminated soils even in the presence of diesel fuel concentration.

English

  Wastes from both industrial and domestic sources, as well as habitat destruction have a substantial impact on the coastal environments. It causes serious problems in many countries and for several seas and oceans which leads to the extinction of several plant and animal species. Many water resources are no longer suitable for drinking or for agriculture as a result of pollution. The main aim of this study was to investigate the efficiency of four brown macroalage as bioindicators for toxic heavy metals (manganese (Mn), copper (Cu), zinc (Zn), arsenite (As), cadmium (Cd), and lead (Pb)) along Al-jubail industrial city coast at Persian Gulf (Saudi Arabia). Brown macroalage samples were collected from three different sites in three time points, January, March and May, 2010. The four collected brown macroalgae were identified as Sargassum angustifolium, Sargassum boveanum, Sargassum latifolium, andPadina gymnospora. The algal samples were cleaned using sea water and distilled water, dried, and the concentrations of various toxic metals were determined. The average concentrations of Mn, Co, Ni and Cd were within the expected limits of un-contaminated areas. However, the results indicate the high level of Zn ion accumulation in all tested brown algae, showing highest concentration in S. angustifolium > P. gymnospora > S. latifolium > S. boveanum with highest Zn concentration of 991 ± 49.1, 988 ± 47.5, 980 ± 44.2, and 911 ± 39.7 μg g-1 dry weights, respectively. In addition, Cu was detected at high concentration of 92.1 ± 3.7 μg g-1 dry weight in S. boveanum. These results clearly indicate the high pollution levels of Al-jubail industrial city coast with Zn and Cu toxic heavy metals, which is mostly due to uncontrolled disposal of industrial waste into coastal area. Furthermore, the consistency of Zn concentrations in all tested brown algae indicated the efficiency of the tested algae, including P. gymnospora, S. angustifolium, S. latifolium, and S. boveanum, for bioaccumulation and bio-monitoring studies of Zn.   Key words: Brown algae, heavy metals, bio-indicators, Sargassum sp., Padina sp.

Bioaccumulation of Zn, Cu and Mn in the Caviar and Muscle of Persian Sturgeon (Acipenser persicus) from the Caspian Sea, Iran

Concentrations of Zn, Cu and Mn were examined in caviar and muscle of the Persian sturgeon (Acipenser persicus) collected from coastal waters of south Caspian Sea during March and April, 2011. Mean Zn, Cu and Mn concentrations in caviar samples were 21.48, 2.05 and 1.66 μg g(-1) wet weight basis, respectively. The mean Zn, Cu and Mn concentrations in muscle tissues were 7.49, 1.00 and 0.34 μg g(-1) wet weight basis, respectively. The mean concentrations of Zn and Cu in caviar and muscle samples were under the permissible limits proposed by the United Kingdom's Ministry of Agriculture, Fisheries and Food (2000).

Bioaccumulation of Cd, Pb and Zn in the edible and inedible tissues of three sturgeon species in the Iranian coastline of the Caspian Sea

The accumulations of Cd, Pb and Zn were determined in edible and inedible tissues of Persian sturgeon (Acipenser persicus; n=27), stellate sturgeon (Acipenser stellatus; n=5) and beluga (Huso huso; n=4) collected from coastal waters of the South Caspian Sea from March to April 2011. Concentrations of metals evaluated in the caviar, muscle, liver, kidney, gills, ovary and heart of the three species of sturgeons have been assessed using the flame and graphite furnace atomic absorption spectrophotometer. Concentrations of Zn, Pb and Cd in the edible and inedible tissues were apparently different among the three species of sturgeons. Especially, beluga heart showed the highest concentrations of Zn and Pb and Cd in Persian sturgeon liver. The analyzed metals were found in the caviar and muscle samples of Persian sturgeon and likewise muscle samples two other sturgeon species at mean concentrations under the permissible limits proposed by MAFF (2000).

Variability of Heavy Metals in Wild Catfish Clarias gariepinus Collected South and North Cairo Area. II. Essential Heavy Metals.

Four surveys were undertaken to investigate the bioaccumulation of Fe, Cu, Zn and Mn in the liver, kidney, gills, skin and muscles of Clarias gariepinus from the River Nile south (Al-Aiat) and north (Barrage) areas of Cairo. Metals bioaccumulation were analyzed then applied to differentiate between the concentrations found at the two locations, between all of the surveys, and the two sexes. No significant seasonal variations detected in the water metals. Fe and Cu are the highest elements and Mn is the least element. Cu is the more element affected by the locality with higher concentrations in Al-Aiat than Barrage. No hazardous effect on the environmental ecosystem observed. Higher concentrations of metals were observed in the tissues of C. gariepinus than the water in which they live. All heavy metals in all organs are present in measurable quantities and still within the safe limits for consumption. Concentrations of the analyzed metals revealed large numbers of significant values concerning location, sex and season differences. Discussion is focused on the significant results.

Dietary (periphyton) and aqueous Zn bioaccumulation dynamics in the mayfly Centroptilum triangulifer

Diet is often the predominant route of trace metal exposure in aquatic insects. In freshwater ecosystems, periphyton serves as a primary source of food to many aquatic insects and is a major sink for trace metals. We investigated the bioconcentration of the essential metal Zn by periphyton using (65)Zn as a radiotracer. At relatively low dissolved concentrations (2-20 μg L(-1)), non steady state Zn bioconcentration by periphyton averaged 6,099 ± 2,430-fold, with much of the variability determined by loading regime (number of renewals and duration of exposures). Labeled periphyton was used as a food source for dietary accumulation studies with the mayfly Centroptilum triangulifer. After 29 days, larvae concentrated Zn 19-, 16- and 17-fold relative to dietary Zn concentrations of 8.1, 43.2 and 82.3 μg g(-1) (dry weight), respectively. Adults from that same cohort only concentrated Zn 8-, 3- and 3- fold relative to those same dietary concentrations, revealing that mayflies lose significant Zn prior to reaching adulthood. Anecdotal evidence suggests that this loss occurs prior to emergence to the subimago, as negligible Zn was found in the subimago to imago exuvium. Across a range of adult tissue concentrations, maternal transfer consistently averaged 26.7 %. Uptake (k(u), 0.26 L g(-1 )d(-1)) and efflux rate constants (k(e), 0.001-0.007 d(-1)) were measured and assimilation efficiencies from dietary Zn concentrations of 4.9 and 59.7 μg Zn g(-1) were estimated to be 88 ± 4 % and 64 ± 15 %, respectively. Both life cycle and biodynamic modeling approaches point towards diet being the primary route of Zn bioaccumulation in this mayfly.

Assessment of phytotoxicity of ZnO NPs on a medicinal plant, Fagopyrum esculentum

Fagopyrum esculentum commonly named as buckwheat plant is pseudocereal food crops and healthy herbs but is not known as a bioindicator of environmental condition. In the present study, the effects of ZnO nanoparticles (NPs) and microparticles (MPs) on plant growth, bioaccumulation, and antioxidative enzyme activity in buckwheat were estimated under hydroponic culture. The significant biomass reduction at concentrations of 10–2,000 mg/L was 7.7–26.4 % for the ZnO NP and 11.4–23.5 % for the ZnO MP treatment, (p < 0.05). ZnO NPs were observed in root cells and root cell surface by scanning electron microscopy and transmission electron microscopy analysis. Zn bioaccumulation in plant increased with increasing treatment concentrations. The upward translocation (translocation factor <0.2) of Zn in plant was higher with the ZnO NP treatment than that with the ZnO MP treatment. Additionally, reactive oxygen species generation by ZnO NPs was estimated as the reduced glutathione level and catalase activity, which would be a predictive biomarker of nanotoxicity. The results are the first study to evaluate the phytotoxicity of ZnO NPs to medicinal plant. F. esculentum can be as a good indicator of plant species in NP-polluted environment.Electronic supplementary materialThe online version of this article (doi:10.1007/s11356-012-1069-8) contains supplementary material, which is available to authorized users.

Heavy metal accumulation by recombinant mammalian metallothionein within Escherichia coli protects against elevated metal exposure

Metallothioneins (MTs) are ubiquitous metal-binding, cysteine-rich, small proteins known to provide protection against toxic heavy metals such as cadmium. In an attempt to increase the ability of bacterial cells to accumulate heavy metals, sheep MTII was produced in fusion with the maltose binding protein (MBP) and localized to the cytoplasmic or periplasmic compartments of Escherichia coli. For all metals tested, higher levels of bioaccumulation were measured with strains over-expressing MBP-MT in comparison with control strains. A marked bioaccumulation of Cd, As, Hg and Zn was observed in the strain over-expressing MBP-MT in the cytoplasm, whereas Cu was accumulated to higher levels when MBP-MT was over-expressed in the periplasm. Metal export systems may also play a role in this bioaccumulation. To illustrate this, we over-expressed MBP-MT in the cytoplasm of two mutant strains of E. coli affected in metal export. The first, deficient in the transporter ZntA described to export numerous divalent metal ions, showed increasing quantities of Zn, Cd, Hg and Pb being bioaccumulated. The second, strain LF20012, deficient in As export, showed that As was bioaccumulated in the form of arsenite. Furthermore, high quantities of accumulated metals, chelated by MBP-MT in the cytoplasm, conferred greater metal resistance levels to the cells in the presence of added toxic metals, such as Cd or Hg, while other metals showed toxic effects when the export systems were deficient. The strain over-expressing MBP-MT in the cytoplasm, in combination, with disruption of metal export systems, could be used to develop strategies for bioremediation.

Heavy Metal Concentrations in Surface Sediments and Manila Clams (Ruditapes philippinarum) from the Dalian Coast, China after the Dalian Port Oil Spill

We conducted an investigation of heavy metal concentrations in Manila clams (Ruditapes philippinarum) and surface sediments after the Dalian Port oil spill. Samples were collected from three mariculture zones (Jinshitan, Dalijia, and Pikou) along the Dalian coast. Heavy metal concentrations in R. philippinarum were consistent and ranked in decreasing order of Zn > Cu > As > Cr > Pb > Cd > Hg, while concentrations in surface sediments were ranked as Zn > Cr > Cu > Pb > As > Cd > Hg, respectively. Bioaccumulation of Zn, Cd, and Hg had obviously occurred in R. philippinarum. Statistically significant correlations (p < 0.05) between concentrations of Pb, Cd, and Hg in R. philippinarum and in surface sediments were observed. Except for Cr and As, heavy metal concentrations in R. philippinarum were well within the legal limits for human consumption.

Bioaccumulation of heavy metals Cu, Zn, and Hg in muscles and liver of the stellate sturgeon (Acipenser stellatus) in the Caspian Sea and their correlation with growth parameters

Bioaccumulation of Cu, Zn, Hg in muscles and liver tissues of stellate sturgeon (Acipenser stellatus) from the southern Caspian Sea was measured. Effects of condition factor (CF), age and hepatosomatic index (HSI) on metal accumulation were also determined. Some 40 stellate sturgeons were collected using gill nets in winter and spring 2007-2008 from the southern shores of the Caspian Sea. Total (TL) and fork (FL) length and weight of all specimens were measured. Cross sections of first ray of pectoral fins were used for age determination. Muscle and liver samples were taken and transported to the laboratory in ice packs and kept in -20 oC prior to analyses. In the laboratory samples were oven dried, digested with HClO3 and HNO3 and diluted with dionized water to 50cc to measure Cu, Zn, and Hg concentration with a flame spectrophotometer. Sequence of metals in Acipenser stellatus was Zn>Hg> Cu in muscle tissues and Zn> Cu> Hg in liver samples. Concentration of Zn was slightly in correlation with age (R= 0.3). A negative correlation was observed between Zn concentrations with condition factor (R= -0.3). Zn concentrations were negatively correlated in muscle tissues (R=-0.3). The results were compared to international standards proposed by MAAF, EEC and NHMRC. Our study showed that accumulation of heavy metals in sturgeon tissues was influenced by concentration of metals in sediment and the physiological state of fish.

Organic Acid Enhanced Soil Risk Element (Cd, Pb and Zn) Leaching and Secondary Bioconcentration in Water Lettuce (Pistia Stratiotes L.) in the Rhizofiltration Process

The use of natural chelates to enhance risk element mobility combined with rhizofiltration by free floating macrophytes have not been thoroughly studied in recent years. The aim of this study was to investigate the efficiency of organic acids in soil by conducting flushing experiments to enhance the mobility of Cd, Pb, and Zn from soil to solution. In addition, the bioaccumulation of Cd, Pb, and Zn, in water lettuce (Pistia stratiotes L.) will be studied as they affect the biomass in the rhizofiltration process. The results revealed that citric and tartaric acids mobilised the highest amount of all risk elements. In comparison to control, citric acid mobilised 71%, 181%, and 112% of Cd, Pb, and Zn while tartaric acid mobilised 70%, 155%, and 135% of Cd, Pb, and Zn respectively. The bioconcentration factor was approximately 2–5 times higher for juvenile plants than mature plants for all treatments as well as for both parts (leaves and roots). The risk element translocation into aerial parts decreased with increased time. Juvenile and mature plants proved a high accumulation potential and a 3 week growth period was observed as a sufficient time period to remove more than 80% of Cd, Pb, and Zn.

Antioxidant enzyme activities as biomarkers of Zn pollution in fluvial biofilms

The potential of the antioxidant enzyme catalase (CAT) and ascorbate peroxidase (APX) as molecular biomarkers of Zn toxicity in freshwater biofilms has been explored in this study jointly with other classical functional and structural endpoints (photosynthetic parameters, algal group composition and bioaccumulation). Biofilms were colonized in an indoor microcosm system for 5 weeks and then exposed to Zn for 5 weeks. To evaluate Zn effects, biofilms were sampled 5 and 3 days before exposure, just before exposure (time 0), and after 6h, 1, 3, 7, 21 and 35 days of metal exposure. Most endpoints measured were affected by Zn exposure (320μgZnL−1) during both periods of exposure. APX was the only functional parameter responding after a few hours of Zn exposure, highlighting its use as an early toxicity biomarker. Structural changes began after 3 days of exposure, starting with a decrease in algal biomass and an increase in the OD 430:665 ratio. Structural changes in biofilm communities were observed after 1 week, leading to a shift from diatoms to cyanobacteria and green algae-dominated communities. CAT activity was thereafter enhanced (after three weeks of exposure) and attributed not only to a direct effect of Zn bioaccumulation but also to an indirect effect of the community composition changes driven by chronic metal exposure. It can be concluded that biofilm antioxidant enzyme activities may provide evidence of early stress caused by metal exposure and also provide information about the mechanism of community adaptation. This information can be of great interest to improve current tools used for risk assessment.

The effect of metals on photosynthesis processes and diatom metrics of biofilm from a metal-contaminated river: A translocation experiment

With the aim of evaluating cause-effect relationships between metal pollution and biofilm structure and function, a translocation study was performed in a metal-polluted stream (the Osor stream “la riera d’Osor”, NE Spain). Biofilm responses were measured as temporal changes in chl-a fluorescence parameters, pigment composition and diatom species composition. Biofilms from a non-polluted site were translocated to four downstream sites presenting a gradient of metal pollution, corresponding to scenarios of low and moderate metal pollution. Metal effects (Zn bioaccumulation, Fe bioaccumulation and Zn in water) were distinguished from other stressors (phosphate concentration in water). Based on the results obtained, a fast bioaccumulation of Zn (after few hours of exposure) was linked to a decrease in photosynthetic efficiency and an enhancement of mechanisms of protection through the xanthophyll cycle. After longer exposure, differences in Zn and Fe bioaccumulation and Zn water concentration between sites were linked to diatom community changes; decrease in diatom cell biovolume, along with a decrease in the IPS index of diatoms. Based on our results, we recommend including Zn in the list of priority pollutant substances of the European Water Framework Directive (2000/60/EC), due to its occurrence and toxicity. In addition, our study supports the use of chl-a fluorescence parameters together with the analysis of photosynthetic pigments of biofilms as suitable functional endpoints of early toxicity. Furthermore, diatom community studies are recommended for their clear response after chronic exposure. However, new diatom indices beyond the use of the IPS are required to increase their sensitivity to metal pollution, e.g. to identify the damage caused by moderate to low metal pollution.

Trace metal pollution and its influence on the community structure of soft bottom molluscs in intertidal areas of the Dar es Salaam coast, Tanzania

The influence of trace metal pollution on the community structure of soft bottom molluscs was investigated in intertidal areas of the Dar es Salaam coast. Significant enrichment of As, Mn, Mo, Sb, and Zn in sediments was recorded. Redundancy analysis indicated that trace metal pollution contributed 68% of the variation in community structure. Monte Carlo permutation test showed that As and Sb contributed significantly to variation in species composition. T-value biplots and van Dobben circles showed that the gastropods Acteon fortis, Assiminea ovata, and Littoraria aberrans, were negatively affected by As and Sb, while the bivalve Semele radiata and the gastropod Conus litteratus were only negatively affected by As. Bioaccumulation of As, Cd, Cu, Mo and Zn occurred in the bivalve Mactra ovalina and the gastropod Polinices mammilla. This calls for regular monitoring and management measures.