Trace Metals In Surface Waters Research Articles

Human Risk Assessment of Trace Metals in Surface Water from Bandama, Bia and Comoé Rivers, Southeast Côte d’Ivoire

Human Risk Assessment of Trace Metals in Surface Water from Bandama, Bia and Comoé Rivers, Southeast Côte d’Ivoire

Trace metals in surface water of the Pechora River and its tributaries: Content, water quality and risks assessment (Arctic Ocean basin)

The article is devoted to the study of trace metals content in the Pechora River and its tributaries, which is the largest river in the Arctic Ocean basin. The study of physico-chemical properties of water showed aerobic conditions of low-mineralised water with pH values suitable for drinking water. Analysis of the content of trace metals has revealed that the main flow of Al, Mn, Co, Cu, Zn, V, As, Mg and Fe into the Pechora River comes from its tributaries. The average content of Cr, Mn, Cu, Zn, Pb, V, As, Mg and Fe in the water of the Pechora River delta was higher than for the main river channel, which indicates the transfer of a large mass of trace metals to the Barents Sea and the Arctic water ecosystem. For the studied river and tributaries, chronic pollution of the Pechora River with Al, Mn, Ba, Fe, Cu, U and Pb metals has adverse effects on waterborne organisms. The degree of contamination of natural waters by metals has been assessed using water quality indices (TMPI, TMEI, TMTI) and public health risks (HI and CR). Low contamination and weak toxicity of the Pechora River water has been determined, but serious contamination, toxicity and high non-carcinogenic risk of some of its tributaries have been observed. A high carcinogenic risk has been established for the consumption of all water sampled. Al, Ni, As, Fe, Mn, Cr, Cd, and Ba were found to be the highest priority contaminating trace metals. At present, contamination of the Pechora River and its tributaries with trace metals is formed under the influence of dissolution processes of rocks of the Ural Mountains, the Taminsky Ridge, underlying mineral deposits, permafrost degradation processes and glacier melting. Anthropogenic factors include oil and gas production and transportation.

Spatial variability of dissolved nickel is enhanced by mesoscale dynamics in the Gulf of Mexico

The Gulf of Mexico (GoM) is one of the most dynamic marginal seas in the world owing to the intrusion of the Loop Current and the shedding of anticyclonic eddies (LCE) that travel westward across the Gulf. However, the impacts of these mesoscale dynamics on the supply and removal of bioessential trace metals in surface waters remain unclear. We study the impact of mesoscale eddies on the distribution of dissolved nickel (Ni), a biologically active element scarcely studied in the region. The vertical distribution of Ni was determined in the deep-water region of the GoM during summer of 2017, when two anticyclonic LCE (Quantum and Poseidon) were present. Nutrient-like profiles of Ni in the GoM resemble those from the Atlantic Ocean, but they showed high spatial variability within the first 1000 m, which was associated with the impact of mesoscale eddies. Similarly to subtropical gyres, macronutrients were almost depleted in surface waters, while Ni never fell below 1.51 nmol kg-1, suggesting low Ni lability or alternatively, slow biological uptake compared to that of macronutrients. In particular, lowest levels of Ni and macronutrients (PO4 and NO3) were recorded in surface waters of the anticyclonic eddies and the Loop Current area. Anticyclonic LCEs deepened these Ni-poor waters pushing the Ni-rich core of Tropical Atlantic Central Water up to 600 m, whereas its shallowest position (up to 200 m) was recorded under cyclonic conditions in Campeche Bay. This eddy-induced vertical displacement of water masses also affected the integrated Ni and macronutrient concentrations in the upper 350 m but without modifying their stoichiometries. We suggest that a significant decrease in surface inventories of Ni and macronutrient in areas impacted by LCEs is a consequence of the trapping of the water within eddies, the biological uptake of Ni and macronutrients combined with their limited replenishment from below, which likely affects autotrophic groups. In conclusion, the mesoscale dynamic permanently present in the GoM play an important role in modifying the vertical distribution of Ni and macronutrients as well as their availability in the upper water column of this marginal sea.

A PMF-SSD based approach for the source apportionment and source-specific ecological risk assessment of Le'an river in Jiangxi Province, China

Identifying the contamination characteristics of trace metals in river and targeting their corresponding potential contamination sources and source-specific ecological risk are of very importance for putting forward effective river environment protection strategies. Here, a detailed investigation was conducted to recognize the contamination and ecological risk characteristics of trace metals in Le'an River. To attain this objective, a PMF-SSD model (Positive Matrix Factorization-Species Sensitivity Distribution) was proposed to evaluate the ecological risk of trace metals in Le'an River. The positive matrix factorization (PMF) was employed to identify the potential source of trace metals in surface water and their corresponding contributions. The ecological risks of the sources were quantitatively calculated by PMF-SSD. In addition, the spatial dissimilarity analysis of the source contribution distributions was also conducted in this study. Results showed that the water environment in Jiangxi were considerably contaminated by trace metals (Cd, Cr, Co, Al, Mn, Cu, Zn and Ni). The concentrations of these trace metals in surface water demonstrated significant spatial variations and the ecological risk lay in high level. Mining activities were identified as the main anthropogenic sources, which should to be strictly regulated.

Vanadium in groundwater aquifers increases the risk of MAC pulmonary infection in O'ahu, Hawai'i.

To identify whether trace metals influence the risk of NTM infection in O'ahu, Hawai'i. A population-based ecologic cohort study was conducted using NTM infection incidence data from patients enrolled at Kaiser Permanente Hawai'i during 2005-2019. We obtained sociodemographic, microbiologic, and geocoded residential data for all Kaiser Permanente Hawai'i beneficiaries. To estimate the risk of NTM pulmonary infection from exposure to groundwater constituents, we obtained groundwater data from three data sources: (1) Water Quality Portal; (2) the Hawai'i Department of Health; and (3) Brigham Young University, Department of Geological Science faculty. Data were aggregated by an aquifer and were associated with the corresponding beneficiary aquifer of residence. We used Poisson regression models with backward elimination to generate models for NTM infection risk as a function of groundwater constituents. We modeled two outcomes: Mycobacterium avium complex (MAC) species and Mycobacterium abscessus group species. For every 1-unit increase in the log concentration of vanadium in groundwater at the aquifer level, infection risk increased by 22% among MAC patients. We did not observe significant associations between water-quality constituents and infection risk among M. abscessus patients. Concentrations of vanadium in groundwater were associated with MAC pulmonary infection in O'ahu, Hawai'i. These findings provide evidence that naturally occurring trace metals influence the presence of NTM in water sources that supply municipal water systems.

Nontuberculous Mycobacteria Infection Risk and Trace Metals in Surface Water: A Population-based Ecologic Epidemiologic Study in Oregon.

Rationale: Nontuberculous mycobacteria (NTM) are ubiquitous environmental bacteria, and some pathogenic species cause lung disease. Environmental factors contribute to increased NTM abundance, with higher potential for exposure and infection. Objectives: To identify water-quality constituents that influence the risk of NTM infection in Oregon. Methods: We conducted a population-based cohort study using patient incidence data from the Oregon statewide NTM laboratory data collected as part of a public health surveillance project from 2007 through 2012. To estimate the risk of NTM pulmonary infection (PI) from exposure to water constituents, we extracted water-quality data from the Water Quality Portal and associated these data with corresponding patient county of residence. Using generalized linear models, we modeled two outcomes: Mycobacterium avium complex species PI and Mycobacterium abscessus group species PI. Results: For every 1-unit increase in the log concentration of vanadium in surface water, infection risk increased by 49% among persons with Mycobacterium avium complex PI. Among those with Mycobacterium abscessus PI, we observed that for every 1-unit increase in the log concentration of molybdenum in surface water, infection risk increased by 41%. The highest risk of infection due to Mycobacterium abscessus group infection was concentrated in counties within the Northwestern region of Oregon. High infection risk associated with Mycobacterium avium complex species did not show any geographic pattern. Conclusions: Concentrations of the trace metals molybdenum and vanadium in surface water sources were associated with NTM infection in Oregon. These findings may help identify regions at higher risk of NTM infection to guide risk reduction strategies.

Hazard Analysis of Trace Metals in Muscle of Sarotherodon Melanotheron and Chrysichthys Nigrodigitatus from Okulu River, Rivers State, Nigeria

Introduction: An instance of fish deaths in marine waters surrounding some communities in Bonny and Andoni Local Government Areas in Rivers State was reported in March-April 2020. This study investigated trace metals hazard in muscle of Tilapia (Sarotherodon melanotheron) and Silver Catfish (Chrysichthys nigrodigitatus) from Okulu River, Rivers State, Nigeria. Materials and Methods: Tissues of 24 samples of Sarotherodon melanotheron and Chrysichthys nigrodigitatus obtained from the river were analyzed using atomic adsorption spectrophotometer, and the health risk was estimated based on estimated daily intake (EDI), target hazard quotient (THQ), and total target hazard quotient (TTHQ). Results: The concentration (mg/kg) of iron, zinc, manganese, copper, cadmium, lead, and chromium in both species ranged 4.00 – 197.30, 9.20 – 35.30, 0.20 – 5.00, 0.00 – 73.10, 0.00 – 1.30, 0.00 – 54.70, and 0.00 – 0.50, respectively. The EDI of trace metals resulting from the consumption of both fish species was higher than the permissible tolerance intake (PTI) mg/day/60kg body weight. The THQ and TTHQ were < 1, indicating that the consumption of this food fish portends no known health concern. However, the carcinogenic risks exceeded the threshold level of 10-6 - 10-4, thus, reflecting carcinogenic tendency. Based on the results obtained, it must be ensured that the effluents discharged into open water bodies meet the recommended limits. Conclusion: There is a need to create awareness among consumers of food fish in the study area. There should be periodic monitoring of trace metals in surface waters and its food fish population to forestall potential health impact on humans.

Time-series sampling of trace metals in surface waters using osmotic sampler with air segmentation and preservative addition

High-resolution time-series concentrations (CTS) are very important for the investigation of the biogeochemical processes of trace metals in the aquatic environment. However, the acquisition of CTS of trace metals in water is still challenging because of the lack of suitable samplers. In this study, an osmotic sampler coupled with air segment injection and preservative addition was employed for time-series sampling of trace metals in surface waters. In the sampler, water sampling and preservative adding are both driven by osmotic pumps (OPs), while air segment injection is accomplished by a timer-controlled micro diaphragm pump. During deployment, the sampling OP continuously draws water through a filter and stores it in a narrow-bore coil. Simultaneously, a preservative OP slowly pushes 30% HNO3 (v/v) into the collected sample for in situ preservation. Periodically, the micro diaphragm pump injects air into the continuous water stream to divide it into water segments, enabling accurate time-stamping. After retrieval, the time-series samples were pumped out from the coil and re-collected to analyze the CTS of analytes. The sampler was deployed in river, reservoir, and marine waters for 26 h and one week to measure CTS of trace metals at time resolutions of 2 h and 12 h. Results showed that the recoveries of a preloaded standard mixture (1.0 μg/L) in all samplers ranged from 93.1% to 117.8%. The measured CTS of Cd, Co, Cr, Cu, Mn, and Ni in the waters only varied in small ranges. Accordingly, the measured CTS data from the sampler were consistent with the obtained concentrations from grab sampling. The relative percent differences between the measurements from two samplers were less than 37.4%. These results demonstrate the reliability and accuracy of the sampler for time-series sampling of the chosen trace metals in surface waters.

Flow-sediment regulation regime influencing mobilization of trace metals in shallow aquifer and surface water in the Yellow River Delta, China

The Yellow River Delta (YRD) is a typical case of frequent interaction between surface water and groundwater under the seasonal flow-sediment regulation regime. A total of 40 samples (20 surface water samples, 19 groundwater samples, and 1 seawater sample), were collected during the high flow (October, 2019). Trace metals, hydrochemical indicators (EC, pH, major ion of Na+, K+, Mg2+, Ca2+, Cl−, SO4 2−, and HCO3 −) and stable isotopes (δ18O and δD) were determined. The impact of water diversion on the hydrochemistry of groundwater was significant, accounting up to a 90% of river discharge in some sites calculated by 2-component mixing model. Factor analysis indicated that Fe, Mn, Al, and B in surface water were closely correlated and were present in the dissolution phase due to sediment remobilization controlled by flow-sediment regulation; Sr was influenced by the dissolution of evaporate salt, while Ba suffered precipitation in the oxidation processes. However, the source of Sr, Mn, B, and Fe in groundwater was accompanied by hydrochemical compositions and per cent surface water, implying that the trace metals in surface water contributed to that of accumulation in the shallow aquifer; Al was influenced by plagioclase weathering, while Ba precipitated too.

Distribution and Health Risk Assessment of Trace Metals in Surface Waters and Groundwater Around Artisanal Gold Mining Areas in Central-western Côte d’Ivoire, West Africa

The present study aimed to evaluate Ni, Cr, Zn, Cd, Hg, and Pb distribution and the health risks in surface waters and groundwater around artisanal mining areas in the central-western Cote d'Ivoire. Trace metals spatial distributions were assessed using ArGIS method. Waters pollution status were ascertained through water pollution indices. Human health risk was investigated using non-carcinogenic and carcinogenic risks indices. In surface waters, the same distribution trends were observed for Ni and Cd, and, for Hg and Pb. While, the distribution patterns of Zn and Cr differed from those of Ni, Cd, Hg, and Pb. Trace metals (Ni, Cr, Cd, Zn, Hg and Pb) concentrations in groundwater were within their guidelines values. While, the averages total of Ni, Cd, Hg, and Pb concentrations for the surface waters exceeded their guidelines values. The pollution status revealed high and low pollution levels of surface waters and groundwater, respectively. Averages of the total non-carcinogenic risk for Hg, Cd, Ni and Pb in surface waters varied between 1.529±1.162 and 80.507±104.615, indicating adverse effects to human health. The averages total carcinogenic risks for Ni, Cd, Pb, and Cr indicated that the population around the artisanal gold mining area could develop cancer. Therefore, it is important to treat waters for removing trace metals before using for domestic purposes.

In Situ Assessment of Donghu Lake China Using Rare Minnow (Gobiocypris rarus).

In this work, rare minnow (Gobiocypris rarus) was applied as a sentinel organism and set in cages at control and test sampling sites in Donghu Lake for 4weeks in March, June, September, and December 2016 to assess the biological toxicity of in situ water. Sampling for active biomonitoring and physicochemical variables was performed weekly. The control was obtained from the outdoor pool of the Institute of Hydrobiology, China. Superoxide dismutase, lipoperoxidation, metallothioneins, acetylcholinesterase activity, and Vtg mRNA expression were determined as biomarkers during the field exposure period. Survival and growth also were monitored to evaluate the overall physiological condition of the fish. The seasonal changes of organic pollutants and trace metals (As, Hg, Cr, Cu, Zn, Cd, Pb) in surface water were determined. The integrated biomarker response (IBR) index was applied to summarize biomarker responses and correlate stress levels with concentrations of organic pollutants and trace metals in the surface water. Results indicated that complex pollution by persistent organic pollutants and heavy metals was present in Donghu Lake and that the in situ exposed organisms were stressed. Moreover, the complex pollution of Donghu Lake in summer and autumn was more serious than that in spring and winter. Active biomonitoring combined with IBR analysis enabled good discrimination among different exposure seasons. The proposed protocol with caged rare minnow revealed marked biological effects caused by the investigated Lake and a useful approach that can easily be extended to monitor water pollution.

Dynamics of trace metals in a shallow coastal ecosystem: insights from the Gulf of Gabès (southern Mediterranean Sea)

Coastal areas are sites of discharge of anthropogenic compounds, such as trace metals. In seawater, trace metals have a strong affinity for particulate organic matter or clay mineral and tend to accumulate in sediments. However, natural events and human activities can cause disturbances in surface sediments involving modification of chemical balances and contamination of surrounding waters. Here, we investigated the dynamics of trace metals in the Sfax coastal area (Gulf of Gabes, southern Mediterranean Sea), a shallow coastal ecosystem impacted by tides and submitted to urban/industrial effluents. We presented the spatial distribution of trace metals concentrations, their potential mobility in sediments and evaluated the potential sources of target elements in surface waters. The highest concentration levels in surficial sediments (3.51 µg/g) and surface waters (0.25 µg/L) were found for Cd. The latter showed a great affinity (50%) for the exchangeable phase while other elements (Cu, Cr and Ni) were found in most residual phases, reducing the environmental risk. Pb and Zn, associated Fe/Mn oxyhydroxides revealed potential inputs from urban and industrial effluents. Multivariate statistical analysis suggested that dissolved trace metals in surface waters were probably derived from effluents/wadis but also from sediment resuspension processes, induced by natural (tides, hydrodynamics) or anthropogenic (dredging) events. Overall, this study highlights the importance of the interactions between sediment and water column for the trace metal dynamics in very shallow coastal environments with an exacerbated pattern for Cd.

Vertical physicochemical parameter distributions and health risk assessment for trace metals in water columns in eastern Lake Tanganyika, Tanzania

The vertical distributions of trace metals and physicochemical parameters in water columns in Kigoma Bay and Kungwe Bay in eastern Lake Tanganyika, Tanzania, were studied. The Al, Ba, Ca, Co, K, Mg, Mn, Mo, Na, Sn, Sr, and V concentrations were low and varied very little with depth. The toxic heavy metal (As, Cr, Cu, Ni, Pb, and Zn) concentrations were relatively high in the surface water, and the Cu, Ni, Pb, and Zn concentrations decreased with depth. Principal component and cluster analyses indicated that the metals in the lake had three main sources. Al, Ba, Ca, Co, Cu, Cr, Mn, Sr, Sn, and V were found to be geogenic; As, Cr, Cu, Mo, Ni, Pb, Sn and Zn anthropogenic; and As, Ca, Co, Mg, and Na biogenic. Human health risk assessments were performed, and it was found that trace metals in the water at most of the sampling sites would cause no potential adverse effects or non-carcinogenic health risks through dermal contact or ingestion. However, trace metals in surface water in Kungwe Bay could have certain adverse effects on human health through the ingestion pathway (the total hazard quotient for ingestion (ΣHQing ) was 1.75 (a value >1 was defined as possibly indicating adverse effects). The Pb ΣHQing for surface water in Kungwe Bay was 1.50 and contributed >80% of the ΣHQing, implying that Pb pollution is a water quality and safety problem that needs to be carefully monitored and the potential sources identified.

Human Health Risk Assessment of Trace Metals in Surface Water Due to Leachate from the Municipal Dumpsite by Pollution Index: A Case Study from Ndawuse River, Abuja, Nigeria

Abstract The study assessed the level of heavy metals in surface water across Ndawuse River near the dumpsite at Phase 1 District of the Federal Capital Territory (FCT), Abuja, Nigeria. The results indicated that oxygen demand, turbidity and heavy metals were above the standard limits set for drinking water. Multivariate analysis using principal component analysis and hierarchical cluster analysis revealed natural and anthropogenic activities as sources of heavy metal contamination. The estimated non-carcinogenic effects using hazard quotient toxicity potential, cumulative hazard index and daily human exposure dose of surface water through ingestion pathway were less than a unity. The estimated carcinogenic risks (CRing) exceeded the suggested potential risk limits, with lead (Pb) having the highest CRing value for all age groups. However, children were found to be more susceptible to heavy metals over a period of time according to the estimated values. The concentration of heavy metals in the investigated river could pose an adverse health risk to several communities that rely on this receiving water bodies for domestic purposes. Therefore, there is need for strict enforcement of environmental laws to protect aquatic ecosystem and to avoid long term cumulative exposure risk that heavy metals may pose on human health.

Suspended particulate matter determines physical speciation of Fe, Mn, and trace metals in surface waters of Loire watershed

This study investigates the spatiotemporal variability of major and trace elements, dissolved organic carbon (DOC), total dissolved solids (TDS), and suspended particulate matter (SPM) in surface waters of several hydrosystems of the Loire River watershed in France. In particular, this study aims to delineate the impact of the abovementioned water physicochemical parameters on natural iron and manganese physical speciation (homoaggregation/heteroaggregation) among fine colloidal and dissolved (< 10nm), colloidal (10-450nm) and particulate (> 450nm) phases in Loire River watershed. Results show that the chemistry of the Loire River watershed is controlled by two end members: magmatic and metamorphic petrographic context on the upper part of the watershed; and sedimentary rocks for the middle and low part of the Loire. The percentage of particulate Fe and Mn increased downstream concurrent with the increase in SPM and major cations concentration, whereas the percentage of colloidal Fe and Mn decreased downstream. Transmission electron microscopy analyses of the colloidal and particulate fractions (from the non-filtered water sample) revealed that heteroaggregation of Fe and Mn rich natural nanoparticles and natural organic matter to the particulate phase is the dominant mechanism. The heteroaggregation controls the partitioning of Fe and Mn in the different fractions, potentially due to the increase in the ionic strength, and divalent cations concentration downstream, and SPM concentration. These findings imply that SPM concentration plays an important role in controlling the fate and behavior of Fe and Mn in various sized fractions. Graphical abstract Physical speciation by heteroaggregation of (Fe-Mn) compounds: high [SPM] → [Fe-Mn] particulate faction; low {SPM] → [Fe-Mn] colloid-dissolved fraction.

Controls on dissolved and particulate iron distributions in surface waters of the Western Antarctic Peninsula shelf

The Western Antarctic Peninsula (WAP) displays high but variable productivity and is also undergoing rapid change. Long-term studies of phytoplankton communities and primary production have suggested transient limitation by the micronutrient iron (Fe), but to date no data have been available to test this hypothesis. Here, we present the first spatially extensive, multi-year measurements of dissolved and particulate trace metals in surface waters to investigate the key sources and sinks of Fe in the central WAP shelf. Surface samples of dissolved and particulate metals were collected throughout the 700 × 200 km grid of the Palmer Long-Term Ecological Research program in three consecutive austral summers (2010 − 2012). Iron concentrations varied widely. Both dissolved and particulate Fe were high in coastal waters (up to 8 nmol kg− 1 and 42 nmol kg− 1, respectively). In contrast, very low Fe concentrations (< 0.1 nmol kg− 1) were widespread in mid- to outer-shelf surface waters, especially in the northern half of the sampling grid, suggesting possible Fe limitation of primary production on the shelf. Sea ice and dust inputs of Fe were minor, although their relative importance increased with distance from shore due to the larger near-shore sources. Sedimentary inputs were inferred from manganese distributions; these were more significant in the northern portion of the grid, and showed interannual variation in intensity. Overall, the interannual distribution of Fe was most closely correlated to that of meteoric water (glacial melt and precipitation). Although the Fe concentrations and relative contributions of dissolved and particulate Fe attributed to meltwater were variable throughout the sampling region, increasing glacial meltwater flux can be expected to increase the delivery of Fe to surface waters of the coastal WAP in the future.

Baseline seasonal investigation of nutrients and trace metals in surface waters and sediments along the Saigon River basin impacted by the megacity of Ho Chi Minh (Vietnam).

The Saigon River, Southern Vietnam, crosses one of the most dynamic developing Megacity in Southeast Asia: Ho Chi Minh City (HCMC). The increased economic, industrial, and domestic developments may affect the environmental quality of water and halieutic resources. In this study, we evaluated the seasonal (dry and wet seasons) biogeochemical state of the Saigon River during two snapshot campaigns conducted along the river basin upstream from HCMC; the Saigon River was characterized by slightly acidic (pH 5.7-7.7) and oxygen-depleted water (dissolved oxygen (DO), 0.36-5.18mgl-1). Nutrients (N-NH4=0.01-2.41, N-NO3=0.14-2.72, and P-PO4=~0-0.42mgl-1), DOC (2.2-8.0mgl-1), POC, and trace metal(oid) (As, Cd, Cr, Cu, Zn, and Hg) concentrations were low showing a good quality of the upstream river. In the urban center area, DO dropped to 0.03mgl-1 accompanied with a rise of nutrient concentrations (e.g., N-NH4, up to 17.7mgl-1) likely originating from wastewater discharges. Trace metal concentrations also rose sharply (e.g., Cr and Hg rose up to 10-fold higher) in both water and sediments but remained under the World Health Organization (WHO) and Vietnamese concentration guidelines. In the downstream estuarine area, the intrusion of marine waters diluted water flowing from HCMC, leading water quality to return close to the state observed upstream from HCMC. In general, levels of nutrient and metal contaminations along the Saigon River during both seasons appear moderate regarding to Vietnamese and WHO guidelines although the urban area is highlighted as the major contributor for metal(oid) emissions. Finally, we showed that apart from wastewater and industrial discharges that affect the river quality, metal(oid) partitioning between solid and solution is controlled by the change in water geochemistry along the continuum during both seasons, such as DO (e.g., for As and Cr) and pH (e.g., for Pb) which drives their sorption/dissolution dynamics.

Health risk assessment and seasonal distribution of dissolved trace metals in surface waters of Kalpakkam, southwest coast of Bay of Bengal

Dissolved trace metal (Cd, Ce, Co, Cr, Cu, Fe, La, Mn, Ni, Pb, U and Zn) concentration in the surface water of Kalpakkam coast was investigated for two consecutive years (2012–14) to understand their seasonal fluctuations, source apportionment and risk assessments. Concentration of metal was determined using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Significant seasonal distribution in metal concentrations was noticed and most metals showed relatively high concentrations during summer season. During the study period metals follow the concentration levels Fe>Zn>Cu>Pb>U>Cr>Mn>Ni>La>Cd>Ce>Co. Principal Component Analysis (PCA) explained 70.12% of the total variance by the first three factors indicating the role of internal and anthropogenic activities in the metal contents in the coastal waters of Kalpakkam. The bioavailability of the metals in dissolved form suggested that the non-cancer and cancer risks posed by them are minimal. The overall hazard index (HQdermal) and cancer risk levels were within the safe limits recommended by WHO. However, the carcinogenic risks of the metals revealed that dermal absorption (CDIdermal) of Fe might be a matter of concern. Summer season has higher Metal Pollution Index (MPI) values, than the remaining period. Metal pollution indices indicated that southwest monsoon (SWM) and northeast monsoon (NEM) periods were less contaminated (MPI: 1.0–2.0; Class-III) as compared to the summer season (MPI: 2.0–4.0; Class-IV).

Assessment of Trace Metals in Surface Water and Sediment Collected from Polluted Coastal Areas of Bangladesh

Assessment of Trace Metals in Surface Water and Sediment Collected from Polluted Coastal Areas of Bangladesh

Pesticide and trace metals in surface waters and sediments of rivers entering the Corner Inlet Marine National Park, Victoria, Australia

Water and sediment samples were collected from up to 17 sites in waterways entering the Corner Inlet Marine National Park monthly between November 2009 and April 2010, with the Chemcatcher passive sampler system deployed at these sites in November 2009 and March 2010. Trace metal concentrations were low, with none occurring at concentrations with the potential for adverse ecological effects. The agrochemical residues data showed the presence of a small number of pesticides at very low concentration (ng/L) in the surface waters of streams entering the Corner Inlet, and as widespread, but still limited contamination of sediments. Concentrations of pesticides detected were relatively low and several orders of magnitude below reported ecotoxicological effect and hazardous concentration values. The low levels of pesticides detected in this study indicate that agricultural industries were responsible agrochemical users. This research project is a rarity in aligning both agrochemical usage data obtained from chemical resellers in the target catchment with residue analysis of environmental samples. Based on frequency of detection and concentrations, prometryn is the priority chemical of concern for both the water and sediments studied, but this chemical was not listed in reseller data. Consequently, the risks may be greater than the field data would suggest, and priorities for monitoring different since some commonly used herbicides (such as glyphosate, phenoxy acid herbicides, and sulfonyl urea herbicides) were not screened. Therefore, researchers, academia, industry, and government need to identify ways to achieve a more coordinated land use approach for obtaining information on the use of chemicals in a catchment, their presence in waterways, and the longer term performance of chemicals, particularly where they are used multiple times in a year.