Metal Concentrations Research Articles

Evaluation of an aquatic liverwort and terrestrial moss as biomonitors of heavy metals associated with particulate matter

In this study, the capacity of the aquatic liverwort Ricciocarpus natans L. and the terrestrial moss Entodon serrulatus Mitt. as biomonitors of heavy metals associated with particulate matter from a highly polluted urban area was evaluated, and concentrations in moss tissues were correlated with concentrations of PM10 and PM2.5 present in the atmosphere. The two species were exposed by the moss bag technique to the pollution of the Toluca Valley Metropolitan Area (TVMA) for two periods of 6 months, using the sites of the Automatic Atmospheric Monitoring Network of the Government of the State of Mexico, and were subsequently analyzed using elemental and structural characterization techniques. The results show that mainly the functional groups -OH and -NH, N-H and C-O on the surface of the liverwort and moss participate in the adsorption of heavy elements. The average enrichment factors of Cd and Pb show to be highly enriched (> 10) in the study area while chromium is not enriched (< 2). The statistical results indicate a temporary variation in the concentration of metals and particles in the atmosphere, where there is a lower concentration of these pollutants in the rainy and dry-cold season and a higher concentration in the dry-hot season and a possible association of Cr and Cd with PM10 and PM2.5. In addition, except for Cr, both species accumulate the metals associated with airborne particulate matter at equivalent levels. There is strong association between PM2.5 and PM10 particles and between the metals Cr-Pb-Fe in R. natans and between PM2.5-PM10 and Fe and between Cd-Cr-Pb in E. serrulatus and these pollutants are mainly associated with sampling sites with the highest concentrations of metals in the TVMA. Although terrestrial moss showed slightly better characteristics than aquatic liverwort as a biomonitor of heavy metals associated with atmospheric particles, these differences were not statistically significant for all metals, so both species could be useful for heavy metal biomonitoring in highly polluted urban areas.

Cerebrovascular accidents association between serum trace elements and toxic metals level, a case-control study.

Cerebrovascular accidents (CVAs) are among the most common complications of patients today. As the prevalence of ischemic CVAs rises, detecting related risk factors is crucial. Metal concentration has previously been considered a major risk factor in several neural complications, and in this study, we will investigate this. In this case-control study, 70 CVA (clinically approved ischemic stroke cases by imaging and NIH Stroke Scale (NIHSS)) and 70 individuals with no history of CVA controls were enrolled as the control group. The serum level of several metals, including Fe (Iron), Co (Cobalt), Ni (Nickel), Cu (copper), Zn (Zinc), Mn (Manganese), Pb (lead), Hg (Mercury), has been assessed using Inductively coupled plasma mass spectrometry (ICP-MS) method. Logistic regression (LR) has also been used to determine the association between metals' levels and CVA occurrence. As the mean age of the CVA group was 48.68 ± 15.25 years and for the non-CVA group was 47.89 ± 9.65 years, the result indicated that the serum level of Cu and Pb has been statically higher in the CVA group (respectively; P < 0.001 and P = 0.002) and Ni level was significantly lower (P = 0.003). Other measured metals' levels (Fe, Co, Ni, Mn, Hg) were not significantly different between CVA and non-CVA groups. In the LR model, all Cu, Pb, and Zn metals had a P value of 0.03 and an odd ratio (OR) and confidence interval (CI) of 1.34 (1.02-1.75), 1.19 (1.01-1.39) and 1.01 (1.001-1.02) respectively. Given that some metals are associated with a higher risk of CVA, researchers and physicians must better understand the risk factors and causes of the burden of CVA. However, further studies with a larger population and investigation of the exact pathogenesis of these metals are needed.

Spatiotemporal discrepancies and risk assessment of toxic heavy metals in surface water of Shitalakhya River around Narayanganj port in Bangladesh

The urban rivers of developing countries like Bangladesh have been severely affected by toxic heavy metal pollution, posing serious ecological and human health risks. This study aimed to investigate the concentrations, spatiotemporal discrepancies, and associated risks of five alarming toxic metals (Pb, Cd, Cr, Cu and Mn) in the surface water of urban Shitalakhya River around Narayanganj port, one of the biggest and most important river ports in Bangladesh. Water samples were collected for three prevailing seasons i.e., pre-monsoon, monsoon, and post-monsoon from five selected sites. Physicochemical properties (color, odor, temperature, DO, pH, EC and TDS) of river water were also assessed, while heavy metal pollution index (HPI), heavy metal evaluation index (HEI) and degree of contamination (CD) were calculated to evaluate the risks associated with toxic metal pollution in river water. The findings revealed that several physicochemical parameters, especially DO, EC and TDS, were not within the standards. The hierarchy of mean heavy metal concentrations in Shitalakhya River water was found as Mn&gt;Cr&gt;Cu&gt;Cd&gt;Pb during pre-monsoon, Mn&gt;Cu&gt;Cr&gt;Cd&gt;Pb during monsoon, and Mn&gt;Cr&gt;Cu&gt;Pb&gt;Cd during post-monsoon season. The metal concentrations were found to be higher in pre-monsoon and post-monsoon seasons, whereas the concentrations of all the heavy metals excluding Mn were within the standards recommended for domestic use, surface water, fisheries and irrigation purposes. The comparative analysis exhibited that the water quality of Shitalakhya River is deteriorating day by day at an alarming rate. HPI showed a critical pollution index value (drinking) for all three seasons, whereas HEI revealed low heavy metal contamination for all sampling stations. The values of CD indicated a high level of contamination in pre-monsoon and post-monsoon but monsoon season. The results confirmed the spatiotemporal discrepancies in toxic metal concentrations and associated ecological and human health risks, possibly resulting from the hydrological and anthropogenic interventions not only associated with port activities. Hence, urgent collective effort and proper monitoring are of utmost importance to safeguard the public health and this urban riverine ecosystem. Int. J. Agril. Res. Innov. Tech. 14(2): 74-84, December 2024

Comprehensive assessment of physicochemical quality, heavy metals, and ecological risks in the Someshwari river water, Netrokona, Bangladesh

This study aimed to assess the physicochemical quality of water, the presence of toxic heavy metals, and the associated ecological risk in the trans-boundary of the Someshwari River as it enters Bangladesh through Netrokona District. Samples were collected over the period from June 2021 to May 2022 from five distinct locations. The investigation examined the current status of various physicochemical parameters of the water, including color, odor, temperature, dissolved oxygen (DO), biological oxygen demand (BOD), electric conductivity (EC), total dissolved solids (TDS), and alkalinity, as well as the concentrations of heavy metals (Pb, Cd, Cr, Cu, and Mn). The findings of the study revealed that temperature, pH, DO, BOD, TDS, EC, and total alkalinity were within established standard limits. The pH values across all water samples exhibited variation within the range of 7.60 to 7.80. Additionally, the concentrations of Pb, Cd, Cu and Mn were found to be within acceptable levels. Notably, no detectable levels of Cr were identified in the river water throughout the three seasons. The HPI values were within the acceptable range, with a range of 42.68 to 92.10 during the pre-monsoon, 26.60 to 48.71 during the monsoon, and 5.57 to 98.00 during the post-monsoon seasons, respectively. Similarly, the HEI values indicated a low level of contamination, with variations from 0.21 to 20.30 in the pre-monsoon, 0.63 to 22.27 in the monsoon, and 5.01 to 33.12 in the post-monsoon seasons, respectively. Mean CD values consistently indicated a lower level of pollution across all three seasons. In summary, the results of this investigation suggest that the water quality in the designated area is suitable for various uses. However, to maintain this water quality, it is strongly recommended that effective awareness programs be implemented to prevent water pollution. Int. J. Agril. Res. Innov. Tech. 14(2): 44-52, December 2024

The importance of organic matter in controlling the metal variability and mobility in seagrass sediments.

Metal contamination in seagrass beds has been extensively studied in the past decades. Most of earlier studies have focused on reporting metal concentration in different compartments of seagrass ecosystem, with little attention given to the role of sediment organic matter in controlling the metal mobility and bioavailability. This study investigated metal contamination in seagrass sediments in Hainan Island, China and illustrated how various geochemical factors impact the spatial variability of the metal concentrations. Particularly, we explored how organic matter influence metal storage and mobility in the seagrass sediments. The enrichment of metals in these sediments was not only associated with levels of organic matter but also their sources. The organic matter content showed positive correlations with both metal concentrations and acid-extractable fractions of chromium, silver, and cadmium, highlighting its significant role in influencing metal accumulation and mobility in sediments. Overall, this research enhances our understanding of metal cycling within seagrass ecosystems and highlights the vital role of seagrass-derived organic matter in regulating metal dynamics.

Metal concentrations, oxidative status and histopathological evaluation of fish species from Doce River, Brazil, after the Fundao dam collapse.

Eight years after the tailings dam collapse in Mariana, MG, Brazil, several aspects of this massive disaster are yet to be elucidated. Our goal was to investigate the impact of the mud flow on 16 fish species collected across 15 points from the Doce River, addressing 12 metal concentrations, tissue oxidative status (antioxidant enzymes and stress biomarkers), and histopathological analyses. The species Trachelyopterus striatulus, Prochilodus vimboides, Loricariichthys castaneus, Lophiosilurus alexandri, Hypostomus affinis, Hoplias intermedius were shown to be the most affected regarding the gills tissue integrity; Hypostomus affinis, Oligosarcus acutirostris, Lophiosilurus alexandri, Pygocentrus nattereri, Hoplosternum littorale, and Loricariichthys castaneus showed the highest levels of liver health. Overall, H. affinis was the most affected species, showing high levels of oxidative and histopathological damage, associated with high arsenic (As) and mercury (Hg) concentrations. In fish sampled from impacted regions, As and Hg exhibited higher concentrations compared to fish from unaffected sites, surpassing all the other analyzed metals. These high metal concentrations might be associated to the tailings dam failure, and As and Hg concentrations were positively correlated with alterations in oxidative stress biomarkers and histopathologies. Our results may be used as baseline for monitoring the environmental challenges that the Doce River fish species are facing at the moment.

Normal levels of Cu and Zn contamination present in swine manure increase the antibiotic resistance gene abundances in composting products

Cu and Zn are abundant heavy metals in swine manure. Heavy metals are not readily biodegradable and can continuously drive the co-selection of antibiotic resistance. Thus, to simulate the effects of different concentrations of heavy metals detected in swine manure on antibiotic resistance genes (ARGs), normal (L) and high (H) concentrations of Cu and Zn were added during composting. Compared with the control (CK), the total relative abundances (RAs) of ARGs in the composting products increased by 0.26–0.28 logs under CuL and ZnL. The total RAs of ARGs decreased by 0.84 logs under ZnH, and the RAs of sul1, tetX, and sul2 were 0.51–1.87 logs lower than those under CK (P < 0.05). Network analysis indicated that intI1 and ISCR1 were associated with the co-occurrence of ARGs and metal resistance genes. After composting, the abundances of intI1 were significantly higher under CuL and ZnL than CK (4.2–8.4 times), and normal concentrations of Cu and Zn promoted the horizontal transfer of ARGs. Moreover, the responses of the potential hosts to Cu and Zn affected the abundances of ARGs during composting. Overall, normal concentrations of heavy metals (CuL and ZnL) increased the ecological risk of ARGs in composting products.

Human Health Risk Assessment of Heavy Metals and Polycyclic Aromatic Hydrocarbons in Seafood from Southern Nigeria’s Coastal Regions

Aim: The levels of heavy metals and polycyclic aromatic hydrocarbons (PAHs) in tilapia fish, prawn, oyster and periwinkle samples from southern Nigeria’s coastal regions were evaluated to determine possible human health risk associated with consumption. Study Design: Ten (10) samples each of the selected seafood were collected from mangrove swamps along Bakana River in the study area. The samples were analyzed for nutrient levels and concentrations of toxic metals and PAHs. Methodology: The concentrations of heavy metals and PAHs in the selected seafood samples were determined using Gas Chromatography Flame Ionization Detector and Atomic Absorption Spectrophotometry. Probable human health risk associated with the seafood consumption for adult and children populations was evaluated using Estimated Daily Intake (EDI), Target Hazard Quotient (THQ) and Carcinogenic Risk (CR) assessment for heavy metals and PAHs. Results: The seafood samples showed the presence of heavy metals (Cr, Cd, Cu, Pb and Zn) but values were all below regulatory permissible limits of 0.6, 0.05, 3.0, 0.2 and 5.0 mg/kg respectively. PAH compounds (fluorene and anthracene) were below detectable limits in the seafood samples; phenanthrene was detected in all the seafood samples but highest in Tilapia fish, recording 28.32±0.05 mg/kg. Benzo (a) pyrene was below detectable limit in the investigated seafood samples. Carcinogenic Risk (CR) assessment values for heavy metals in the seafood samples were significantly (p&lt;0.05) high for Cd, Pb, Cr and Ni in both adult and children populations. CR values for PAHs were within regulatory threshold of 10E-6 – 10E-4. Conclusion: This study revealed that individual carcinogenic potencies for heavy metals (Cd, Pb, Ni, Cr) in the seafood samples exceed the guideline screening value for human consumption, indicating high potential for carcinogenic risk. Our findings suggest that Bakana river is exposed to substantial amount of carcinogenic environmental pollutants associated with deleterious environmental and epidemiological effects.

Risk Assessment of Carcinogenic Metals in Soils and Food Crops Near Brick Kiln Cluster

A study was conducted in the Charia area, Hathazari, Chattogram district, Bangladesh to determine the levels of carcinogenic metals Cd and Pb in soils and crop plants in the vicinity of brick kiln clusters. The health risk was evaluated by computing cancer risk using the US EPA model. The amounts of Cd and Pb in the soils and the parts of crop plants were determined by AAS. The soils of the study area were acidic. Metal concentrations indicating the anthropogenic input of Cd and Pd in the soils was in the range from 0.27 to 1.07 mg/kg dry soil and from 19.07 to 52.07 mg/kg dry soil respectively. Accumulation of Cd (0.00 to 0.27 mg/kg) and Pb (0.09 to 0.13 mg/kg) in the studied crops. A significantly high correlation (r = 0.89, p &lt; 0.001) of the elements between soil and plant suggests that the source of contamination is the soil under study. 72% of all the studied edible plant parts exceeded the recommended threshold risk limit of the cumulative cancer risk (ƩILCR), which was higher in the edible part of fruit crops than in root crops. Cd was the dominant carcinogen in the study area. J. Asiat. Soc. Bangladesh, Sci. 50(1-2): 17-31, June-December 2024

Assessment of heavy metals concentration and health risk in four species of Persian Gulf sharks in Hormozgan Province.

Marine pollution is a growing concern that threatens ecosystems and endangers human health. This study investigated the bioaccumulation of six heavy metals, including zinc (Zn), copper (Cu), lead (Pb), mercury (Hg), nickel (Ni), and cadmium (Cd) in the muscle tissue of Codium arabicum, Coilia dussumieri, Rhizoprionodon oligolinx, and R. acutus from in Hormozgan province, Iran, between November 2023 and March 2024. The primary focus was to provide insights into these elements' distribution and accumulation patterns in Persian Gulf sharks. Moreover, it aimed to assess the potential risks of chemical contamination in the Persian Gulf. Samples were collected, prepared through acid digestion, and analyzed using Atomic absorption spectrometry (AAS) to qualitatively and quantitatively determine Zn, Cu, Ni, Pb, Cd, and Hg concentrations. The mean heavy metal concentrations in the examined sharks follow the order Zn > Cu > Ni > Pb > Cd > Hg. The highest mean concentrations of all the tested heavy metals were observed in C. arabica. Furthermore, the THQ value for Hg (1.07) in C. arabica raised concerns, particularly for individuals with high fish consumption, such as fishermen. With the THQ value exceeding 1, there is a clear need for heightened concern regarding the carcinogenic risk associated with dietary mercury exposure. Consequently, our findings showed the initial account of metal concentrations in Persian Gulf sharks, indicating elevated concentrations in individuals that may lead to sub-lethal effects. In conclusion, these results emphasized the potential toxicity of C. arabica meat and held significant implications for human consumers.

Integrated assessment of heavy metal pollution in the great bačka canal: Comparing active and passive sampling methods.

This study investigates the environmental risks posed by heavy metals in sediment from the Great Bačka Canal using both active and passive sampling methods. The necessity of this research lies in the critical need to address sediment contamination in ecological hotspots and enhance sediment management practices. Active sampling revealed total heavy metal concentrations, while sequential extraction showed bioavailability varied across metal fractions. Passive sampling with SPeeper™ quantified freely dissolved metal concentrations in sediment pore water, identifying zinc (41μg/L) as the most bioavailable metal. Risk indices, including Igeo (geo-accumulation index) and IWCTU (interstitial water criteria toxic units), revealed low to moderate contamination levels. Although copper content classified the sediment as extremely polluted (195.7mg/kg), its low bioavailability (16μg/L in pore water) mitigates immediate ecological risks. These findings emphasize the importance of integrating passive sampling in regulatory frameworks for a realistic environmental risk assessment of sediments.

The interplay of gut microbiota and heavy metals in multiple sclerosis patients.

Multiple Sclerosis (MS) is a chronic inflammatory disease characterized by central nervous system (CNS). In this study, the concentration of heavy metals was measured in stool samples of MS patients by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) method and compared with healthy people. Also, another goal of this study is to investigate the alteration of the gut microbiome of MS patients by metagenomics technique based on the 16S rRNA gene sequencing. The IL-10 ELISA assay showed no significant differences between the serum level of the IL-10 in the patients and the control group (p=0.510). Heavy metal measurement by ICP-MS showed significantly higher levels of arsenic (As, Mean=32.77μg/kg), nickel (Ni, Mean=7.154μg/kg), manganese (Mn, Mean=3723μg/kg), and zinc (Zn, Mean=5508μg/kg) in the stool samples of the MS group compared to the control group, while concentrations of iron (Fe, Mean=9585μg/kg), lead (Pb, Mean=18.54μg/kg), titanium (Ti, Mean=69.69μg/kg), and tin (Sn, Mean=13.92μg/kg) were significantly lower. The result of gut microbiome analysis showed an increase in the abundance of the Verrumicrobiaceae, Lachnospiraceae and Ruminococcaceae families was considerably increased in MS patients compared to the control group (p<0.05). This study reports that high levels of heavy metals such as Ars, Ni, Mn, and Zn, deficiency of Fe, Pb, Ti, and Sn, and alteration of the gut microbiome are involved in the pathogenesis of MS. The novelty of this study lies in its multi-faceted approach to understanding MS by integrating the measurement of heavy metals in stool samples with the analysis of gut microbiome alterations, thereby providing comprehensive insights into heavy metals, the gut microbiome, and potential therapeutic avenues. This study suggests several potential applications and practical implications based on its findings regarding heavy metals, gut microbiome alterations, and IL-10 levels in MS. First, the identification of elevated levels of specific heavy metals and deficiencies in others may lead to targeted screening and monitoring, informing preventive strategies for MS patients. Additionally, the observed gut microbiome changes could facilitate the development of microbiome-based therapies, such as probiotics or dietary interventions, aimed at restoring microbial balance. Finally, exploring the interplay between heavy metals, gut microbiome, and immune response may guide the creation of novel therapeutic interventions, ultimately enhancing treatment efficacy and providing new avenues for managing MS, thereby alleviating the burden of this chronic condition.

Trace element transport by volcanic gases at Vulcano (Sicily, Italy) – Speciation, deposition and fluxes

The geochemistry of trace elements in volcanic gas emissions at Vulcano (Sicily, Italy) was investigated. Trace element concentrations in 94–412 °C fumarole gases span over 10 orders of magnitude, from ~0.01 pmol/mol to ~300 μmol/mol, with some metalloids (B, Si) being the most abundant, followed by alkali, alkaline earth, and certain transition metals, and rare earth elements typically displaying the lowest concentrations. Thermodynamic modeling predicts most trace elements to be transported as chloride, hydroxide, and mixed hydroxy-chloro gas species (LiCl, KCl, NaCl, RbCl and CsCl, Be(OH)2, Mg(OH)2, MgCl2, CaCl2, SrCl2, CaCl(OH), TiOCl2, VOCl, VOCl2, VOCl3, NbOCl3, Cr(OH)3, CrCl3, Fe(OH)2, FeCl2 Co(OH)2, CoCl2, Ni(OH)2 to NiCl2, Cd(OH)2, CdCl2, Re(OH)3, ReCl3, ZnCl2, AgCl, WO2(OH)2, Al(OH)3, Si(OH)4, B(OH)4, TlO, GaCl3, SbCl, MnCl2, CuCl). Sulfide, hydrate, and elemental gas species are also important for some elements (Cd, AuS, Hg, PbS2, BiS, Bi, AsS, As2S3, TeS, SeH, SeS). However, for many trace elements, speciation remains uncertain or unknown due to a lack of thermodynamic data. Upon cooling and decompression of the volcanic gas, most trace elements are predicted to reach gas-solid equilibrium, resulting in the formation of secondary minerals. At high temperatures (~700–1000 °C), the mineral assemblage forming is dominated by quartz, Ca-Na-K feldspars, and Mg-pyroxene, containing minor concentrations of other alkali and alkaline earth metals. Further cooling and decompression leads to the formation of minerals including magnetite, pyrite, chalcocite, and chalcopyrite together with other less abundant oxides (V, Cr, Ga, W, and Sn) and sulfides (Zn, Pb, Ni, Co, Cd, Mo, Ag, As, and Bi), and eventually a range of sulfates and sulfosalts (Li, K, Na, Rb, Cs, Be, Mg, Ca, Sr, Bi, Mn, Fe, Zn, Pb, and Sn) at the lowest temperatures (~100–300 °C). For most trace elements, fumarole emission concentrations reflect higher gas-solid equilibrium temperatures than those observed during sampling, suggesting gas-solid equilibria at high temperatures followed by incomplete re-equilibration upon further cooling near the surface.Trace element fluxes span over eight orders of magnitude, ranging from >100 kg/day to ~1·10−6 kg/day. Silica, Al, and B consistently exhibit the highest fluxes, followed by alkali and alkaline earth metals, various transition metals and metalloids, with rare earth elements and actinides displaying the lowest fluxes. Generally, the trace element fluxes are lower compared to neighboring Stromboli and Etna, except for Pb, Bi, B, As, Sb, and Te.

Ecological and Health Risk Assessment of Heavy Metals and Organochlorine Pesticides in Water and Sediments from Otamiri River in Imo State, Nigeria

Ecological and health risk of selected heavy metals and Organochlorine pesticide residues (OCPs) were assessed in Water and Sediments from Otamiri River in Imo state, Nigeria. Water and sediment samples were collected during rainy and dry periods from three different points and mixed together to form a composite sample. Pesticide residues and heavy metals were analysed using gas chromatography-mass spectrometry and atomic absorption spectrophotometer respectively. The concentration of heavy metal during rainy and dry season ranged from ND to 1.56 mg/l and ND to 3.61 mg/l for water samples, 0.005 to 1.8 mg/kg, and 0.008 to 1.0 mg/kg for sediments respectively. The geo-accumulation index Igeo(x) of heavy metals on sediment ranged from 0 to 0.7 while the values of pollution index were greater than one, signifying heavy metal pollution status of the river. The ecological risk index showed that Nickel and Cadmium had moderate to considerable ecological risk ranging from 129.9-348. The OCP residues concentration ranged from ND to 6.35 mg/l and ND to 4.55 mg/l for water samples, ND to 3.22 mg/kg and ND to 3.5 mg/kg for sediments during rainy and dry season respectively, with predominance of BHCs, DDTs and heptachlor epoxide in water and sediment matrixes. The pesticide residues found in the present study were generally below the maximum residues limit (MRL) set by FAO/WHO bodies. Ecological risk using the Risk quotient was found to be (RQ ≥1) during both seasons and shows higher risks for β-HCH, endosulphan sulfate and p,p′-DDT. The non-carcinogenic risk hazard index (HI) values of both exposure routes were less than one. Conversely, the estimated carcinogenic risk by OCPs through ingestion exposure ranged from 8.142E−9 to 1.20E−7 and 6.36E-7 to 6.44E-4 while dermal range from 3.4E-11 to 2.14E-8 and 7.14E-7 to 8.6E-4 for adults and children respectively, showing considerable carcinogenic risk associated to p,p′-DDT, heptachlor epoxide, α- HCH and aldrin. There is need for regular monitoring of the river to ensure water quality sustainability due to environmental and health risk of the levels of heavy metals and OCPs.

Unmasking heavy metal contamination: Tracing, risk estimating and source fingerprinting from coastal sediments of the Payra River in Bangladesh.

The Payra River, cicual for fish breeding, feeding and nursery in coastal Bangladesh, faces heavy contamination from industrial activities, agricultural runoff and poor waste management. This study used ICP-MS to assess metal contamination levels, risk status and potential sources in river sediment. The findings showed that the mean concentrations (mg/kg) of metals followed the decreasing order: Mn (434.24±75.91)>Zn (66.42±12.86)>Cr (44.59±8.98)>Ni (40.30±7.43)>Cu (34.07±6.84)>Co (15.72±2.84)>Pb (14.60±5.56)>As (4.70±0.72)>Hg (0.28±0.21)>Cd (0.10±0.03) with Mn significantly exceeding the recommended guidelines. Although contamination factors (CF<1) and the pollution load index (PLI<1) indicated low pollution, Hg and Cd posed greater ecological risks. However, the Risk Index (RI<150) showed overall low pollution risk. Sediment ranged from uncontaminated to moderately contaminated (Igeo=0-1). Non-carcinogenic risks were minimal (HQ<1), but children were more vulnerable to As (HI=2.40E-01) and Cr (HI=2.17E-01). Carcinogenic risks were also higher for children, particularly from As (CR=8.37E-06) and Pb (CR=6.10E-06). Pearson correlation, principal component analysis (PCA), cluster analysis (CA) and spatial analyses indicated shared sources for As, Hg, and Cd, with Mn likely from different sources. The PMF model identified three pollution sources: natural agricultural activities (23.7%), anthropogenic activities (54.43%), and industrial activities (23.74%).

Association between chronic ambient heavy metal exposure and mental health in Korean adult patients with asthma and the general population.

Insufficient evidence is available to confirm the effect of exposure to airborne metals on mental disorders, particularly among asthmatics. We aimed to investigate the effect of airborne metal exposure on mental health responses in asthmatics and the general population. Using nationally representative cross-sectional data, a total of 47,796 adults were analyzed. We assessed the associations between mental health factors, such as perceived stress, depressive symptoms, and suicidal ideation, and individuals' annual average exposure to airborne metals, including lead, cadmium, chromium, copper, manganese, and iron, over 14 years using multiple logistic regression. The associations were compared using the propensity score matching (PSM) method. The odds ratios (OR) and 95% confidence intervals (CI) for mental health outcomes were calculated for an interquartile range (IQR) increase in the concentration of each airborne metal. Exposure to airborne metals was significantly associated with increased odds of adverse mental health in asthmatics. Significant associations between all ambient heavy metal contaminants and suicidal ideation were found in both asthmatic patients and the general population. After PSM, exposure to all ambient heavy metal contaminants showed significant associations with suicidal ideation in patients with asthma, whereas only iron exposure was significantly associated with suicidal ideation in the general population. After adjusting for perceived stress and depressive symptoms, similar patterns were also observed. Exposure to lead (OR: 1.99; 95% CI: 1.45-2.72) showed particularly a strong association with suicidal ideation in asthmatics. This study suggests that exposure to airborne metals significantly increases depressive symptoms and suicidal ideation, especially in individuals with asthma. Additional clinical research is needed to better understand these associations.

Pollution affects even oceanic marine protected areas in Southwestern Atlantic.

Reefs are facing a global decline with sewage pollution emerging as a significant and poorly understood threat. Inadequate wastewater management and disorderly urbanization contribute to water pollution globally. Tropical Southwestern Atlantic comprises a set of oceanic Marine Protected Areas (MPAs) including the Fernando de Noronha Archipelago in Brazil, which has experienced significant population growth without expanding the sewage infrastructure. We mapped and quantified marine pollution in these MPAs, characterizing pollution sources and evaluating their effects on benthic and fish communities in 13 reef sites. We quantified nutrients, metals and metalloid, microplastics, fecal sterols, and Polycyclic Aromatic Hydrocarbons (PAHs) in both water and sediment samples. We also used isotopic tracing on macroalgae to identify the origin of organic matter and characterized benthic and fish communities, and algae biomass at each site. Pollution was more pronounced in the multiple-use area but also affected no-take areas. Effluents from wastewater treatment plants did not meet legislative standards, and reefs in the multiple-use area were enriched in orthophosphate and ammonia compared to those in the no-take area. Nitrogen isotopes in macroalgae revealed sewage-derived nitrogen throughout the multiple-use area. Nutrient enriched sites exhibited higher abundances of fast-growing and opportunistic green macroalgae, and higher biomass of brown macroalgae. The port area, within the multiple-use area, showed high PAHs, coprostanol and metal(loid) concentrations, suggesting untreated sewage and nautical chemical pollution. Microplastics were widespread in sediment and water samples. We documented the pervasive impacts of marine pollution on reef habitats even within marine protected areas in oceanic regions, demonstrating that local pollution control, sewage management and regulating procedures in port areas are critical to protect marine ecosystems. Comparisons with previous studies suggest marine pollution has substantially increased in the Archipelago in the last ten years. This is the first comprehensive assessment of marine pollution in an oceanic environment in Southwestern Atlantic, showing these isolated environments are not immune to pollution impacts.

The diving beetle, Cybister lateralimarginalis (De Geer, 1774), as a bioindicator for subcellular changes affected by heavy metal(loid) pollution in freshwater ecosystems.

The present study assessed Cybister lateralimarginalis as a model species for ecotoxicological studies of metal(loid) bioaccumulation in freshwater ecosystems, by optimising protocols and analysing biomarker activities and metal(loid) concentrations from different sites and investigating their association. To accomplish this, levels of arsenic (As), selenium (Se), cadmium (Cd), mercury (Hg), and lead (Pb) were analysed, as well as a set of biomarkers were evaluated, esterase activity and oxidative stress biomarkers: fluorescence- and glutathione-based. C. lateralimarginalis were sampled in the spring/summer of 2023 along the Sava, Drava and Danube floodplains in Croatia. C. lateralimarginalis samples from Sava floodplain (Mužilovčica) showed altered carboxylesterase (CES) activity, lower glutathione (GSH) levels, and elevated Hg and As concentrations. The Weighted Pollution Index (WPI) indicated moderate pollution at the Sava floodplain, possibly due to agricultural or petrochemical impacts. At the Drava floodplain (Podravlje), higher glutathione S-transferase (GST) activity and elevated Cd, Hg, and As concentrations were observed, likely from soil accumulation, while Stara Drava beetles had lower GSH levels, suggesting agricultural impacts. Despite this, the Drava floodplain showed the lowest WPI. Higher GST activity was noted at the Danube floodplain (Kopački rit and Topoljski Dunavac), with reactive oxygen species (ROS) concentrations (Kopački rit and Podunavlje) possibly reflecting agricultural practices or illegal hunting. The present research successfully applied C. lateralimarginalis as a bioindicator species for assessing metal(loid)s in different environments, highlighting its reliability as an abundant apex predator, emphasizing the significance of integrating biomarker response evaluation into pollutant monitoring for efficient environmental risk assessment in freshwater ecosystems.

Mapping trace metal footprints: Distribution, sources, and risk assessment in coastal sediments near a heavy industrial zone in Bangladesh.

This study investigated nine trace metals (Cr, Co, Cu, Cd, Ni, Mn, Fe, Zn, and Pb) concentrations of coastal sediments adjacent to a heavily industrialized area of Bangladesh using AAS. The most prevalent metals were zinc, with lesser amounts of Cd and Co. Pb, and Cd levels were higher than world standards, with a considerable enrichment of Pb at station 9. Ecological risk assessments showed moderate to high contamination, particularly by Pb and Cd. The Nemerow integrated pollution index demonstrated that overall pollution was low, but the levels about Cd were still concerning. All stations had hazard indices below 1 but chronic exposure to Ni, presents grounds for concern. Industry, urbanization, traffic, and agricultural runoff along with lithogenic sources have been identified to be the main sources of pollution using receptor modeling. The outcomes underscore the urgency that management measures must be taken to safeguard ecosystem and public health.

Quantification and recovery prospects of critical metals and rare earth elements in Victorian brown coal fly ash: A promising secondary source for critical metal extraction

Coal fly ash (CFA), an anthropogenic waste generated from the combustion of coal, is in research focus for the potential it holds in extracting critical metals. Within the classification of critical metals, includes a group of 16 commercially significant metals known as rare earth elements (REEs). The supply of REEs is touted as one of the building blocks of the 21st century to realize a sustainable future. High demand projections for the future coupled with market monopolization, provide an impetus to extract REEs from secondary resources such as CFA. In this study, three Victorian brown CFA samples were examined, quantifying 41 metals and 16 REEs. All three CFA samples had an outlook coefficient (i.e., ratio of the relative amount of critical REE to the relative amount of excess REE) > 0.7, with an observed light REE enrichment and Eu anomaly, implicating the samples as a suitable feedstock for REE extraction. Quantification studies rendered Loy Yang CFA, from the largest power station in Australia, to be rich with REEs with a total metal concentration of 418 mg/kg, followed by CFA from other power stations (Yallourn: 73.6 mg/kg and Morwell: 36.1 mg/kg). A comparative study for different methods of calibration during inductively coupled plasma - mass spectrometry analysis (and external vs internal calibration), depicted the reproducible nature of results while using an internal standard. Subsequently an in-house developed multi-element standard addition method is proposed, within an accuracy of 2–50 %. A new sequential extraction method for studying modes of occurrences in CFA, depicting REE association with larger fractionation, is explored, with results rendering REE association with: aluminosilicate bound (~ 61.2 %) > acid soluble fraction (23.1 %) > crystalline Fe bound (5.9 %) > organic matter bound (5.3 %) > amorphous Fe bound (3.5 % TREE) > Mn-oxide bound (0.9 % TREE) > water soluble mineral bound (0.1 % TREE). This underpins the strong REE association in the residual and acid soluble fraction in brown CFA.