Pb In Sediments Research Articles

Heavy Metal Pollution in Indonesian Waters

Marine pollution, including heavy metals, is prevalent in Indonesian waters. Previous studies have found evidence of Pb, Cd, Hg, Al and Fe metal contamination in sediments and green mussels. This study used survey research. Heavy metal pollution is increasingly accumulating so that if it is not controlled it is feared that it will have an impact on public health, especially people who live around the coast. The research method was conducted using survey techniques. This study aims to estimate the burden of heavy metal pollution in the ocean. The research was conducted in 5 (five) areas of Indonesia, namely the East Coast of Sumatra, Winongo River in Yogyakarta, Semarang Bay, Bandengan Waters Kendal Central Java, and Ratai Bay Pasewaran Regency in areas with high human and heavy metal impacts. On average, the total results of heavy metal pollution exceed environmental quality standards. The situation in the 5 (five) research areas shows heavy metal pollution is very concerning because it is higher than the marine quality standard. The average concentrations of the measured elements in water were Al >Fe > Cu > Cd, with average values in descending order of 1.08 mg/L, 0.545 mg/L, 0.035 mg/L, and 0.005 mg/L, respectively. Environmental management should be implemented with the aim of reducing heavy metal pollution in Indonesian waters.

Pollution Characteristics, Sources and Assessment of Heavy Metals(Hms) in Surface Sediments of Ningyuan River in Hainan Province, China

Heavy metals are of wide concern due to their high toxicity, bioaccumulation and non-degradability. In this study, eight heavy metals (Cr, Mn, Ni, Cu, Zn, As, Cd, Pb) in the surface sediments of Ningyuan River were studied to investigate the distribution pattern, pollution status and potential pollution sources, and it was concluded that the concentration distribution of heavy metals in sediments is highly consistent with the population distribution pattern in space and there is a certain degree of risk of Cd pollution, and the heavy metals mainly come from mineral weathering, agricultural and shipping wastes.

Assessment of heavy metals in fish and sediments from river Mtakuja in the vicinity of a gold mine in Tanzania

Concentrations of heavy metals namely Cr, Fe, Cu, Zn, As, Cd and Pb in African Sharptooth Catfish (clarias gariepinus) and sediment from river Mtakuja Tanzania were analyzed using the Energy Dispersive X-ray Fluorescence spectrometry technique. 32 samples from fish and sediment were investigated. The results show that the concentration of heavy metals was higher in upstream areas than in the downstream area. The concentration of Fe of 428.5 mg/kg in catfish from the upstream area was about 2 times 243.8 mg/kg obtained from the same fish in the downstream area. Similar cases observed for sediments with Fe concentration of 127626.9 mg/kg from upstream that was about 6 times higher than that of 21460.3 mg/kg from downstream area. The concentration of 44.8 mg/kg for Cu in the upstream area sediment was also about 2 times higher than 23.2 mg/kg in the downstream area sediment, while for as the concentration of 13.2 mg/kg was measured in the upstream, which is which is more than 5 times 2.5 mg/kg measured in downstream. The concentration of Cr in the catfish was 17.6 mg/kg which is higher than the permissible limit values of 0.8 mg/kg set by the European Commission (EC), 0.2 mg/kg set by the Food and Agricultural Organization (FAO) and 0.15 mg/kg the World Health Organization (WHO) limit. Moreover, the concentration of Cd was 3.0 mg/kg, which is above the permissible level of 0.2 mg/kg recommended by the EC and WHO. A positive correlation exists between the Cu, Pb, Fe and Cd concentration found in sediments and fish samples. The results show that the river Mtakuja is polluted by mining waste, domestic and agrochemical activities. This suggest that, there is a need for regular monitoring of heavy metal in river Mtakuja in order to monitor and protect aquatic organisms and health of benefactors of this river.

Biokonsentrasi Timbal Dan Kadmium Terhadap Penaeus merguiensis Dalam Air Dan Sedimen Di Perairan Desa Sungsang I

Sungsang Village is located at the mouth of the Musi River making this area dense with settlements and transportation activities, this contributes to damage and results in decreased water quality. This study aims to analyze the concentrations of Pb and Cd in water, sediment and white shrimp (Penaeus merguiensis) and examine the level of accumulation of Pb and Cd through the BCF values of Pb and Cd in white shrimp (Penaeus merguiensis) in water and sediment in the waters of Sungsang I Village. Results the study showed that the average concentration of Pb in water in the waters of Sungsang I Village was 0.104 mg/L, exceeding the threshold value in Kep.Minister of State for the Environment No. 51 of 2004. The average Pb content in sediments is 24.892 mg/Kg, still below the quality standards of the Guidelines for the Protection and Management of Aquatic Sediment Quality in Ontario. The average concentration of Pb in jerbung shrimp is 0.809 mg/Kg, this value exceeds the limit set by BPOM. The results of the Cd test showed that the average water content, sediment, and jerbung shrimp were 0.013 mg/L, 0.174 mg/Kg and 0.127 mg/Kg. The BCF Pb value of shrimp-sediment was 7.779 and BCF Pb of shrimp-sediment was 0.033. The BCF Cd of shrimp-sediments was 9.769 and the BCF Cd of shrimp-sediments was 0.730. The Pb and Cd bioconcentration values of the jerbung shrimp (Penaeus merguiensis) in water and sediment are included in the low accumulative category, because the BCF value is <100.

The Ecological-Health Risks of Potentially Toxic Metals in the Surface Sediments and Leaves of Salt-Secreting Avicennia officinalis as Potential Phytoremediators: A Field-Based Biomonitoring Study from Klang Mangrove Area.

This study aimed to evaluate the ecological-health risks of potentially toxic metals in the surface sediments on the Klang mangrove ecosystem and assessed the phytoremediation potential of Avicennia officinalis collected from the area. The results showed that the concentrations (mg/kg dry weight) of Cu, Ni, Pb and Zn in the surface sediments ranged between 5.30-63.8, 14.2-32.7, 30.3-62.3, and 46.4-269, respectively. The ecological risk values of the surface sediments indicated that Ni, Pb and Zn were all classified as 'low potential ecological risk', while the Cu ecological risk ranged between 'low potential ecological risk' and 'considerable potential ecological risk'. For the health risks on the sediments, all of the values of hazard index for Cu, Ni, Pb and Zn, based on a combination of three pathways, indicated < 1.00, showing that the four metals are non-carcinogenic. Based on the bioconcentration factor values, it can be concluded that the lamina has better potential as a phytoremediator of essential Cu, Zn and Fe. In contrast, midrib plus petiole has better potential as a phytoremediator of non-essential Pb and Ni. To mitigate the threats to the Klang mangrove ecosystem, the information offered in the present study can be employed in the monitoring and provision of the ecological-health risks of potentially toxic metals in the Klang mangrove ecosystem. Hence, the present findings can be employed for developing a water-energy-food framework for managing the Klang mangrove ecosystem.

Quantitative analysis of heavy metals by laser-induced breakdown spectroscopy technique in association with temperature control and KCl additive

In order to avoid the spectral signal instability and low detection accuracy originating from “transient plasma” produced by laser-induced breakdown (LIBS) technology, the LIBS system based on three-dimensional scaffold was developed to optimize the optical fiber detection position. The spectral signal quality of samples with different contents of KCl additives (0%–100%) at 20–280 °C was analyzed. The double spectral line internal standard model of Cd and Pb elements in sediment was established. The experimental results show that the signal-to-noise ratio of Cd and Al in the sediment with 15% KCl additive at 180 °C is 1.78 and 1.39 times higher than that without additive at room temperature. The R2 of the calibration model for Cd and Pb in sediment with the double enhancement method increased from 0.938 08 and 0.948 80 to 0.963 41 and 0.952 61. The spectral line integral area bispectral line internal scale model R2 is improved to 0.990 34 and 0.988 83. The results showed that the sample heating combined with KCl additive could improve the quality of the spectral signal and increase the detection sensitivity.

ТОКСИКОЛОГИЧЕСКИЕ ИССЛЕДОВАНИЯ ВОДЫ И ДОННЫХ ОТЛОЖЕНИЙ УГЛИЧСКОГО ВОДОХРАНИЛИЩА ЗА ПЕРИОД 2012–2020 ГГ.

A long-term assessment of the toxicological condition of certain areas of the Uglich reservoir is given based on the results of bioassay of water and bottom sediments. During the research period 2012–2020, there was a tendency of the toxicity reduction of water in all sections of the reservoir. The maximum values of reproductive indicators of Ceriodaphnia affinis were registered in 2019. The toxicity of bottom sediments had a slight tendency to decrease in the upper section of the reservoir and did not change in the middle and lower sections. During the teratological study of the Uglich reservoir in 2012–2013 years it was found that the proportion of chironomid larvae with pathomorphological changes in the structures of the mouth parts during the observation period was on average 14.5%, which is higher than the established control (6.7–7.0%) and background values (0–8.0%). The results of the bioassay are confirmed by analytical data on water and sediment pollution. Significant differences in the pollution coefficient of water between the reservoir areas, both in individual elements and in total, have not been recorded. The highest values of the total and average pollution coefficient were reached in the middle section, where higher concentrations of Cu and Zn were determined. Despite the tendency of decreasing concentrations of Cr, Ni, Cu, Zn, Cd and Pb in the bottom sediments of the reservoir, the levels of Cd, Cr, Ni and Zn exceeded their background concentrations established for the Upper Volga basin.

Analysis of Lead (Pb) Heavy Metal Content in Tengkuyung Snail (Cerithidea obtuse) and Sediment in the Kuala Mangrove Area of Singkawang City

Tengkuyung (Cerithidea obtuse) is one of the many snails that live in mangrove areas, being a source of food and the economy, especially for people in coastal areas. Land and sea development and transportation activities have the potential to become a source of Pb contamination in tengkuyung and its environment. This study aims to determine the concentration of lead metal (Pb) in sediments and tengkuyung in the Kuala mangrove area of Singkawang City. Sampling was carried out at two station points. Measurement of heavy metal lead (Pb) in sediments and tengkuyung was carried out using atomic absorption spectrophotometry (SAA) method. The results showed that the content of lead (Pb) in the sediment and tengkuyung at station 1 was 0.0914 µg/g and <0.0070 (µg/g), while at station 2 it was 0.3927 µg/g and <0.0070 (µg/g). The content of Pb metal in tengkuyung meat still meets the eligibility for consumption because it is below the threshold according to SNI no. 7387 in 2009, which is 0.5 mg/kg (0.5 ppm).

Bioconcentration of Lead at Avicennia Marina in Mangunharjo, Semarang Coastal Area

This study aims to determine the bioconcentration of heavy metal Lead Pb in seawater, sediment, and mangrove plants of Avicennia marina and to determine the bioconcentration factor of heavy metal Lead Pb in mangrove which was conducted in January 2022 in Mangunharjo coastal area. The method used in this research was a survey method with quantitative analysis. The samples of A. marina mangroves were divided into three categories of stem diameter, namely small (3 – 8 cm), medium (6 – 15 cm), and large (11 – 23 cm). Measurement of heavy metal concentrations using AAS (Atomic Absroption Spectrophotometry). Heavy metal bioconsentration in Mangunharjo is classified as high exceeding quality standards. The study revealed that the concentration of heavy metal Lead Pb in the seawater ranged from 0.672 - 0.867 mg/L, in sediments it ranged from 56.50 – 65.96 mg/kg, and in the roots and leaves of mangroves A. marina ranged from 6.209 – 24,883 mg/kg. The bioconcentration factor of heavy metal Lead Pb ranges from 0.185 to 0.227, so that the mangrove A. marina in Mangunharjo Water Area can be classified as an excluder species.

HEAVY METAL LEVELS IN WATER, SEDIMENT AND BIOACCUMULATION INDEX IN FISH (Chrysicthys walkeri) FROM WARRI RIVER

Bioaccumulation of any heavy metal above its maximum limits invariably results tothe detrimental health of an organism. This present study was carried out to evaluatethe levels of eight heavy metals (Fe, Pb, Mn, Ni, Cu, Zn, Cr and Cd) in surface water,sediment and bioaccumulation index of (Chrysicthys walkeri) from Warri River, DeltaState, Nigeria. Samples were collected between the period of July to September,2015 from two designated stations. The order of heavy metal mean rank profile, insurface water, sediment and fish were Pb>Mn>Fe>Zn>Cr>Cd>Ni>Cu;Fe>Zn>Ni>Cu>Mn>Cd>Pb>Cr and Pb>Ni>Zn>Mn>Cd>Fe>Cr>Cu respectively.When compared with regulatory standards of WHO, FAO and FEPA threshold limitmost of the metals were above the limits for both water, sediment and fish Tissue.The bioaccumulation index of fish were above BI ? 1.0 indicating possibility ofecological concern. These findings implies that Warri River is polluted andconsumption of these fishes could have grave health consequences even with theexcellent condition factor of the fishes. Therefore, the input of pollutants into this rivershould be monitored in order to avoid associated risks

Cascading effects of Pb on the environmental and symbiotic microbiota and tadpoles' physiology based on field data and laboratory validation

Heavy metal pollution poses a serious threat to ecosystems. Currently, there is a lack of field data that would enable us to gain a systematic understanding of the influences of heavy metals on aquatic ecosystems, especially the interactions between environments and animals. We studied the relationships between the variations in heavy metal concentrations (10 species including Pb in sediments and surface water), the community structure of environmental and symbiotic microbiota, and the gut traits of Bufo gargarizans tadpoles across 16 sampling sites on the Chengdu Plain through rigorous statistical analysis and laboratory validation. The results show that heavy metal concentrations, especially the Pb concentration of the sediment, are linked to the variations in sediment and tadpoles' gut microbiomes but not to water microbiota. For the sediment microbiota, Pb causes a trade-off between the proportions of Burkholderiales and Verrucomicrobiae and affects the methane, sulfide, and nitrate metabolisms. For tadpoles, a high sediment Pb content leads to a low abundance of gut aerobic bacteria and a large relative gut weight under both field and laboratory conditions. In addition, Pb promotes the growth of B. gargarizans tadpoles under laboratory conditions. These effects seem to be beneficial to tadpoles. However, a high Pb content leads to a low abundance of probiotic bacteria (e.g., Verrucomicrobiae, Eubacteriaceae, and Cetobacterium) and a high abundance of pathogenic bacteria in the gut and environment, suggesting potential health risks posed by Pb. Interestingly, there is a causal relationship between Pb-induced variations in sediment and symbiotic microbiotas, and the latter is further linked to the variation in relative gut weight of tadpoles. This suggests a cascading effect of Pb on the ecosystem. In conclusion, our results indicate that among the heavy metals, the Pb in sediment is a critical factor affecting the aquatic ecosystem through an environment-gut-physiology pathway mediated by microbiota.

Removing Lead from Contaminated Sediment Using Indium-Based Perovskite Precursor.

Heavy metal pollution in river and lake sediments seriously damages river ecological safety and indirectly affects human health. The existing research mainly focuses on how to adsorb pollutants and repair sediment, and how the reuse of these pollutants may be a new technology to control sediment pollutants. The rapid development of perovskite solar cells in recent years has attracted a lot of attention, among which lead (Pb) halide perovskites have very excellent photoelectric performance. In this study, we propose a novel idea of introducing indium (In)-based perovskite to replace Pb (II) ions dispersed in river and lake sediment. Three sediment samples from a river in Shanghai Peace Park were collected to analyze the distribution of heavy metal Pb. We mixed the digestion solution of sediment with the prepared CH3NH3(MA)InICl2 solution and found that indium (In) in perovskite precursor solution would be gradually replaced by Pb in sediments. An in situ synchrotron radiation XRD experiment was performed to reveal the reaction mechanism of solutions and provide a good research platform for the comprehensive reuse of sediment in the future. This study provides a new method of remediation of heavy metal pollution in river and lake sediments.

Dynamics of heavy metals in the fine sediments from a subtropical forest headwater stream during a rainy season

ABSTRACT Headwater streams, as the capillaries of rivers, largely control the functional integrity of the entire river network. Headwater stream sediments, especially fine sediments, are essential ecosystem components and dominant reservoirs for heavy metals, with these reservoirs significantly affecting their cycling in streams. However, the dynamics of heavy metals in headwater stream sediments are not well assessed in the literature. Here, we assessed the temporal and spatial storage dynamics of several common heavy metals (i.e., Mn, Zn, Cu, Cr, Cd, and Pb) in the fine sediments from a typical subtropical forest headwater stream during the rainy season of 2021 (Mar–Aug). We found that (1) the mean storage of fine sediment of heavy metals was ordered Mn (21.57 g m−2) > Pb (2.53 g m−2) > Zn (2.27 g m−2) > Cr (0.66 g m−2) > Cu (0.12 g m−2) > Cd (0.006 g m−2); (2) their storage had a transient increase during the rainy season, followed by a decrease, but storage of both Zn and Cr was unevenly distributed from stream source to mouth; and (3) the key factors controlling heavy metal storage were water alkalinity, temperature, and pH, as well as monthly precipitation. These findings suggest that forest headwater streams can store heavy metals, but the amounts vary across temporal and spatial scales. Our results help us better understand the role of headwater streams in storing and transferring materials in forest ecosystems.

Trace metals in urbanized coasts: The central Atlantic of Morocco as a case study

This study describes the contamination, accumulation, and ecological risk assessment of five trace metals (Cd, Pb, Cu, Zn, and Cr) in sediments of an urbanized beach in the central Atlantic coastline of Morocco. The two-year investigation (2018 and 2019) included six sampling sites along a 6 km coastal reach. In both years, none of the studied trace metals exceeded the background or the sediment quality guidelines (SQGs). The eco-toxicological indices revealed low degree of contamination, unpolluted ecosystem, and low ecological risk of metals. However, Cd exceeded the background value and some SQGs following the increase of anthropogenic activities in 2019. Likewise, it indicated unpolluted to moderately polluted sediment as well as moderate ecological risk. Overall, it is highly recommended to mitigate the avoidable anthropogenic activities (marine litter generation, sewage discharge, intense urbanization, and vehicle traffic on the beach) that lead to the elevation of metal pollution in the study area.

Greener sample preparation method for direct determination of Cd(II) and Pb(II) in river sediment based on an aqueous biphasic system with functionalized ionic liquids

Although sample preparation, as an unavoidable step of the analytical process should be simple, it is very often identified as a bottleneck. Simplicity of sample preparation based on cost-effective and non-hazardous materials is mandatory for any sustainable and environmental friendly approach. Aqueous biphasic systems (ABS), based on functionalized ionic liquids (FILs) are acceptable alternatives to classical extraction procedures, due to the replacement of organic solvent with diluted aqueous-soluble ionic liquids. In this work, two water soluble FILs based on 2-mercaptobenzothiazolate anion, [mbt]: 1-butyl-3-methylimidazolium [mbt] ([bmim][mbt]) and 1-ethyl-3-methylimidazolium [mbt] ([emim][mbt]), were designed and synthesized in order to selectively extract Cd(II) and Pb(II) from the river sediment. It was found that [mbt]– anion acts as the ligand and forms complexes with Cd(II) and Pb(II) which are responsible for their efficient extraction, while cation is more responsible for the formation of ABS. Partition coefficients of 408 and 180 for Cd(II) and Pb(II), respectively, were obtained using ABS based on [bmim][mbt]. Direct extraction of Cd(II) and Pb(II) from the river sediment has been investigated and obtained optimal conditions are: 60 min direct contact of the aqueous solution of [bmim][mbt] and the sediment sample at 90 °C, followed by formation of ABS upon addition of potassium citrate. Using AGRE and AGREEprep tools greenness of the proposed method for direct extraction of Cd(II) and Pb(II) from the sediment are calculated. Obtained values of 0.69 and 0.71 for Cd(II) and Pb(II) extraction, respectively, showed a high level of the greenness of the proposed method.

Macrozoobenthic diversity and heavy metals (Pb and Hg) accumulation in Bone River Gorontalo Indonesia

The heavy metal pollution on benthic macroinvertebrate communities in Bone River has not been studied. This present study determined to investigate the diversity of the macrozoobenthic trough the length of Bone River concerning the heavy metals leads and mercury at eight sampling stations. The samples were taken in July 2021. A sample of four representative macro zoobenthic families (Hydropsychidae, Baetidae and Elmidae) was also used to analyze metal bioaccumulation. The macrozoobenthic recorded in this study comprise of ten orders and 35 families with a total of 3146 individuals. Diptera, Ephemeroptera, Coleoptera, and Trichoptera dominate the population size of benthic. The diversity indices show the low and medium categories but favour a better macrozoobenthic development. Monitoring studies show that the concentration of Pb in sediments is much higher than that of mercury. Metal accumulation in sediments showed fluctuations but did not reflect macrozoobenthic metal concentrations. The bioconcentration factor (BCF) value generally indicates that the three taxa are categorized in the low accumulative category.

Heavy metals in coastal soils and sediments of the ponds in Samara

The total contents of Mn, Cr, Ni, Cu, Zn, Pb and Cd in foreshore soils and bottom sediments of 20 ponds have been investigated for the first time in Samara by the method of spectrometry with inductively coupled plasma. It is shown that polymetallic pollution of coastal soils and bottom sediments of 16 ponds out of 20 considered is acceptable; 3 ponds, located in the 13th microdistrict (small pond) and on the Solnechnaya street (large and small ponds), are characterized by moderately hazardous pollution with heavy metals; 1 pond, located in the area of the former Hippodrome, has a high level of pollution of coastal soils. Cu, Zn and Pb should be considered to be the main elements that significantly affected the ecological state of coastal soils and bottom sediments of the studied ponds. Their content in selected samples ranged: from 0,3 to 20,3 for Cu, from 0,2 to 14,9 units for Zn, from 0,2 to 25,2 units of background concentrations to Pb. The analysis of heavy metals average levels in coastal soils and bottom sediments of Samara ponds showed, that bottom sediments were enriched with all analyzed metals except Mn in comparison with coastal soils, whereas Mn was accumulated to upper levels in coastal soils. The location of water bodies in various parts of the urban area relief caused differences between the levels of heavy metals accumulation. For instance, the coastal soils of the ponds located on the watershed between the Saratov reservoir and the Samara River accumulated heavy metals more actively than the coastal soils of the ponds on the Volga slope. The accumulation of heavy metals in bottom sediments on the watershed was more active for Mn, Cr, Zn and Cd whereas in the ponds on the Volga slope it was shown for Ni, Cu and Pb.

Metallothionein level in the larva of Cheumatopsyche sp. and the relationship between heavy metal concentration in Bone River, Gorontalo, Indonesia

Abstract. Kadim MK, Herawati FY, Arfiati D, Hertik AMS. 2022. Metallothionein level in the larva of Cheumatopsyche sp. and the relationship between heavy metal concentration in Bone River, Gorontalo, Indonesia. Biodiversitas 23: 5942-5950. This study aims to confirm that the larvae of Cheumatopsyche sp. contain a metal-binding protein, metallothionein, in their body and correlate it with heavy metal concentrations in the larval tissues and sediments in Bone River. Pb, Cd and Hg concentrations in sediment, tissue and Metallothionein (MT) levels were analyzed in several areas with different metal contamination. The Pb concentration in the sediment averaged 33.6 ppm; Hg 0.17 ppm; Cd 0.125 ppm. Total metals concentration in the whole body of Cheumatopsyche sp. ranged from 0.424 to 0.781, while the MT content ranged from 4637 to 6930 ng.g-1. The results revealed that the larvae could accumulate different metals and be more effective in accumulating Hg than Pb and Cd, regardless of the level of metal concentration in the sediment. Metal concentrations measured in Cheumatopsyche sp. showed a significant correlation with metals in the sediment. Metallothionein levels throughout the larval body showed differences in different areas of metal contamination and this correlated with the concentrations of Pb, Cd, and Hg measured in the larval tissue, thus reflecting their bioavailability in the environment. The results also showed that even under exposure to low metal concentrations, MT was still detectable in Cheumatopsyche sp. and proved to be a good predictor of metal accumulation.

Distribution, historical variations, and geochemical fractions of toxic trace metals and their ecological risks in sediments of the Nanliu River Estuary, South China

In this study, the historical variation (210Pb dating) and distribution of toxic trace metals in sediments of the Nanliu River Estuary (NRE) were studied to understand the spatiotemporal variation therein and related risks. Geochemical fractions of trace metals (Pb, Cu, Cr, Zn, and Ni) were also analyzed using the fractionation technique. The results suggested that the concentrations of trace metals are higher in the western part of the estuary, and that Pb was significantly enriched. The NRE has experienced rapid economic development during the past four decades, but a decreasing trend of trace metals content after 2000 was observed. This may be due to effective implementation of national environmental control measures. Zn, Ni, Cr, Cu, and Pb in the surface sediments of the NRE exist mainly in residual form. The order of trace metals based on the risk assessment code (RAC) is Zn > Cu > Ni > Pb > Cr. According to enrichment factor (EF) and geo-accumulation index (Igeo) values, Hg, As, and Pb in the sediment of the NRE cause moderate levels of pollution and require attention. Based on the geochemical method, anthropogenic contributions of Cd, Zn, Pb, and Cu in the sediments of the NRE exceeded 50 % after 1980, possibly corresponding to the rapid industrial development and economic growth in the NRE resulting from the “reform and opening up”.

Assessment of metal contamination in an urbanized estuary (Atlantic Ocean) using crabs as biomonitors: A multiple biomarker approach

Estuarine environments, which are complex and sensitive coastal system, and are the final receptacle of several human wastes. Consequently, biomonitoring contaminants, such as metals, within these environments and developing scientific-based tools to conserve them have become particularly importat in recent years. Therefore, in the present study, we determined the levels of certain metals (Cd, Cu, Pb, Zn, Mn, Ni, Cr and Fe) both in sediments and in a key ecological benthic species, the burrowing crab Neohelice granulata, in sites of the Bahía Blanca estuary (SW Atlantic Ocean) with different anthropogenic impacts. We combined these records with geochemical indices and enzymatic and non-enzymatic biochemical biomarkers as early warning signals of contamination and damage to establish an integrated metal contamination profile. Our results indicated that some metals like Cu moderately contaminate the estuary and that the primary input of metals in this area is due to malfunctioning sewage discharges. Crabs exhibited the following pattern of metal accumulation: Fe ≥ Cu > Zn > Mn > Ni > Cd. Pb and Cr were under the method detection limit, and Cu was probably bioaccumulated from sediments. Metal concentrations showed significant differences according to the sites and seasons (p > 0.05) and not strictly to the crab gender. Besides, a similar pattern was observed for biomarkers, and the integrated biomarker response allowed establishing different oxidative stress patterns, according not only to human impacts but also to the seasonal physiological needs of this species and environmental endpoints (salinity, temperature, and pH). This work demonstrates that environmental factors also affect the metal influx in crabs and the activity of biomarkers beyond the source and fate of these elements. This information is vital for future integrated monitoring programs.