Priority sources identification and risks assessment of heavy metal(loid)s in agricultural soils of a typical antimony mining watershed.

Heavy metal(loid) (HM) pollution in agricultural soils has become an environmental concern in antimony (Sb) mining areas. However, priority pollution sources identification and deep understanding of environmental risks of HMs face great challenges due to multiple and complex pollution sources coexist. Herein, an integrated approach was conducted to distinguish pollution sources and assess human health risk (HHR) and ecological risk (ER) in a typical Sb mining watershed in Southern China. This approach combines absolute principal component score-multiple linear regression (APCS-MLR) and positive matrix factorization (PMF) models with ER and HHR assessments. Four pollution sources were distinguished for both models, and APCS-MLR model was more accurate and plausible. Predominant HM concentration source was natural source (39.1%), followed by industrial and agricultural activities (23.0%), unknown sources (21.5%) and Sb mining and smelting activities (16.4%). Although natural source contributed the most to HM concentrations, it did not pose a significant ER. Industrial and agricultural activities predominantly contributed to ER, and attention should be paid to Cd and Sb. Sb mining and smelting activities were primary anthropogenic sources of HHR, particularly Sb and As contaminations. Considering ER and HHR assessments, Sb mining and smelting, and industrial and agricultural activities are critical sources, causing serious ecological and health threats. This study showed the advantages of multiple receptor model application in obtaining reliable source identification and providing better source-oriented risk assessments. HM pollution management, such as regulating mining and smelting and implementing soil remediation in polluted agricultural soils, is strongly recommended for protecting ecosystems and humans.

PAHs contamination in ports: Status, sources and risks.

Polycyclic aromatic hydrocarbons (PAHs) constitute important organic contaminants that have been degrading coastal ecosystems over the years. Evaluating PAH status in port ecosystems aligns with societal goals of maintaining clean habitats and sustainability. This comprehensive review systematically analyzed 123 articles, exploring the global distribution, sources, and ecological risks linked to PAH contamination in ports, focusing on water, sediment, and biota. The mean concentrations of 16 PAHs in water, sediment, and biota across worldwide ports were 175.63 ± 178.37 ng/L, 1592.65 ± 1836.5 µg/kg, and 268.47 ± 235.84 µg/kg, respectively. In line with PAH emissions and use in Asia, Asian ports had the highest PAH concentrations for water and biota, while African ports had the highest PAH concentrations for sediment. The temporal trend in PAH accumulation in sediments globally suggests stability. However, PAH concentrations in water and biota of global ports exhibit increasing trends, signaling aggravating PAH contamination within port aquatic ecosystems. Some ports exhibited elevated PAH levels, particularly in sediments with 4.5 %, 9.5 %, and 21 % of the ports categorized as very poor, poor, and moderate quality. Some PAH isomers exceeded guidelines, including the carcinogenic Benzo(a)pyrene (BaP). Coal, biomass, and petroleum combustion were major sources for PAHs. The structure of ports significantly influences the concentrations of PAHs. PAH concentrations in sediments of semi-enclosed ports were 3.5 times higher than those in open ports, while PAH concentrations in water and biota of semi-enclosed ports were lower than those in open ports. Finally, risk analyses conducted through Monte Carlo simulation indicated moderate to high risks to aquatic species, with probabilities of 74.8 % in water and 34.4 % in sediments of ports worldwide. This review underscores the imperative to delve deeper into the accumulation of PAHs and similar pollutants in ports for effective management and environmental protection.

Surface water quality, public health, and ecological risks in Bangladesh-a systematic review and meta-analysis over the last two decades.

Water quality has recently emerged as one of the utmost severe ecological problems being faced by the developing countries all over the world, and Bangladesh is no exception. Both surface and groundwater sources contain different contaminants, which lead to numerous deaths due to water-borne diseases, particularly among children. This study presents one of the most comprehensive reviews on the current status of water quality in Bangladesh with a special emphasis on both conventional pollutants and emerging contaminants. Data show that urban rivers in Bangladesh are in a critical condition, especially Korotoa, Teesta, Rupsha, Pashur, and Padma. The Buriganga River and few locations in the Turag, Balu, Sitalakhya, and Karnaphuli rivers have dissolvable oxygen (DO) levels of almost zero. Many waterways contain traces of NO3, NO2, and PO4-3 pollutants. The majority of the rivers in Bangladesh also have Zn, Cu, Fe, Pb, Cd, Ni, Mn, As, and Cr concentrations that exceed the WHO permissible limits for safe drinking water, while their metal concentrations exceed the safety threshold for irrigation. Mercury poses the greatest hazard with 90.91% of the samples falling into the highest risk category. Mercury is followed by zinc 57.53% and copper 29.16% in terms of the dangers they pose to public health and the ecosystem. Results show that a considerable percentage of the population is at risk, being exposed to contaminated water. Despite hundreds of cryptosporidiosis cases reported, fecal contamination, i.e., Cryptosporidium, is totally ignored and need serious considerations to be regularly monitored in source water.

Industrial impacts on vanadium contamination in sediments of Chinese rivers and bays.

Vanadium, like many trace metals, is persistent and detrimental to ecosystems at elevated concentrations. Likewise, it is versatile, functional, and used in many industries. Jiaozhou Bay (JZB) and Laizhou Bay (LZB) are valuable coastal ecosystems in China coexisting with several of these vanadium-related industries; however, limited studies have been conducted regarding vanadium occurrence, distribution, sources and risks in sediments. 208 surface sediment samples were collected from rivers and bays over two years and analyzed using inductively coupled plasma optical emission spectrometry. Overall, sediments near vanadium-related industries have significantly higher vanadium concentrations than those near traditional industries, with 30.3% and 22.9% higher average concentrations of vanadium in sediments of JZB and LZB, respectively. Vanadium accumulation at LZB is positively correlated with fine sediment, oxides (e.g., Fe, Ti, Mn), and organic matter content, while temporal changes in parts of JZB highlight the impacts of oxides, pH, and redox conditions on its accumulation. After geochemical normalization, the concentrations in marine samples from LZB showed slightly polluted sediments under the Modified Nemerow pollution index. Likewise, the elevated concentrations of vanadium in JZB, rivers and bay, were classified as slightly polluted and correlated with anthropogenic activities, such as the coal and petrochemical industries. Temporal changes indicated higher enrichments in 2019. Last, humans could be responsible for up to 46.8% and 16.2% of the vanadium accumulation in JZB and LZB, respectively, yet risks to species remain limited.

Watershed seasonality regulating vanadium concentrations and ecological risks in the coastal aquatic habitats of the northwest Pacific.

Vanadium is a component of different natural and industrial products and a widely used metal, which, nonetheless, has only garnered attention in recent years owing to its potential risks. Six sampling trips were conducted over different seasons and years, collecting 108 samples from rivers and 232 from the bays and analyzed using high-precision inductively coupled plasma mass spectrometry. This study investigated the sources, spatiotemporal characteristics, and risks of vanadium in the aquatic ecosystems of two typical bays of the Northwest Pacific that have strong links with vanadium-related industries. Likewise, the health and ecological risks were assessed using probabilistic and deterministic approaches. Overall, vanadium concentrations were higher in Jiaozhou Bay (JZB: 0.41-52.7 µg L-1) than in Laizhou Bay (LZB: 0.39-17.27 µg L-1), with concentrations higher than the majority of the worldwide studies. Vanadium-realted industries significantly impacted (p < 0.05) the metal concentrations in the rivers with 54.22% (40.73-150%) and 54.45% (27.66%-68.87%) greater concentrations in JZB and LZB rivers. In addition, vanadium exhibited significant seasonal variation, and higher values were quantified during the monsoon period at LZB owing to the greater catchment area. Impacted by smaller freshwater inputs, the post-monsoon period had substantial impacts on JZB, and vanadium in the rivers and bays was significantly higher during the winter. Despite some concentrations being higher than that indicated in the drinking water guidelines established by China, vanadium presents low to null risks to the population as per both approaches. Last, species with limited resilience are likely to face medium to high risks, with an incidence of 65-93% using the probabilistic method and 52-97% using the deterministic assessment.

Modeling water inequality and water security: The role of water governance.

Water Inequality, Water Security and Water Governance are fundamental parameters that affect the sustainable use of water resources. Through policy formulation and decision-making, Water Governance determines both Water Security and Water Inequality. Largely, where Water Inequality exists, Water Security is undermined through unsustainable water use practices that lead to pollution of water resources, conflicts, hoarding of water, and poor sanitation. Incidentally, the interconnectedness of Water Governance, Water Inequality and Water Security has not been investigated previously. This study modified the Gini coefficient and used a Logistics Growth of Water Resources Model (LGWR Model) to access Water Inequality and Water Security mathematically, and discussed the connected role of Water Governance. We tested the validity of both models by calculating the actual Water Inequality and Water Security of Ghana. We also discussed the implications of Water Inequality on Water Security and the overarching role of Water Governance. The results show that regional Water Inequality is widespread in some parts. The Volta region showed the highest Water Inequality (Gini index of 0.58), while the Central region showed the lowest (Gini index of 0.15). Water Security is moderately sustainable. The use of water resources is currently stress-free. It was estimated to maintain such status until 2132 ± 18 when Ghana will consume half of the current total water resources of 53.2 billion cubic meters. Effectively, Water Inequality is a threat to Water Security, results in poverty, under-development heightens tensions in water use, and causes instability. With proper Water Governance, Water Inequality can be eliminated through formulating and implementing approaches that engender equal allocation and sustainable use of water resources.

Spatiotemporal partition dynamics of typical herbicides at a turbid river estuary.

Organic pollutants are ubiquitous in estuarine areas, nonetheless, the transport mechanisms of herbicides in such areas are limited. Atrazine and acetochlor were analyzed in suspended particle matter (SPM), surface sediment, and surface water from the Yellow River estuary and the surrounding rivers and sea. Among these rivers, the Yellow River contributes the most herbicide flux to the sea annually. The herbicide concentrations in water and sediment decreased from the estuarine areas to the deep sea. The fugacity fraction values of atrazine exceeded 0.5 in the Yellow River estuary, which supported that the herbicides in sediment desorbed at the estuarine areas. The herbicide in the SPM showed high concentration in the outer sea and increased as a power function with decreasing SPM content. The increasing partition capacity indicated that the herbicides tended to sink into sediment, increasing the ecological risk posed by herbicides. The ecological risk of acetochlor deserves continuous attention.

Use, exposure, and environmental impacts of pesticides in Pakistan: a critical review.

The excessive use of pesticides is posing major threats to humans and the environment. However, the environmental exposure and impact of pesticides in Pakistan have yet been systematically reviewed, despite the country's leading role in pesticide use. Therefore, this study identified and then reviewed 85 peer-reviewed scientific publications on the topic. It was found that, compared to the worldwide average, Pakistan had high consumptions of pesticides, with an alarming increase of 1169% in the last two decades. The quantities of pesticides used followed an order of pyrethroids > organophosphates > organochlorines > carbamates, but organochlorines were the most problematic due to their environmental occurrence, the ability to transport across the media, and identified human and ecological toxicities. Additionally, the misuse or overuse of pesticides by farmers is prevailing due to insufficient knowledge about the risks, which leads to high risks in occupational exposure. These issues are further aggravated by the illegal use or continuous impacts of banned organochlorine pesticides. For the future, we suggested the establishment of organized monitoring, assessment, and reporting program based on environmental laws to minimize contamination and exposure to pesticides in Pakistan. Remediation of the contaminated areas to mitigate the adverse environmental-cum-health impacts are recommended in the most affected regions.

Vanadium pollution and health risks in marine ecosystems: Anthropogenic sources over natural contributions.

Vanadium has been classified as a potentially toxic metal and has been given limited attention in comparison to similar trace metals. Similarly, worldwide and continental vanadium pollution and risks remain contested. Here, we synthesized the worldwide concentration of vanadium in marine ecosystems with the relevant ecological and human health risks. We found that vanadium in biota and seawater collected from Asia shows significant increases over the temporal analysis, with rates similar to those reported for vanadium consumption and production. Furthermore, invertebrates have a higher concentration of vanadium than fishes. Similarly, we demonstrate that sediments classified as polluted have concentrations that are not directly correlated with the highest concentrations across continents. Finally, ecological risks were higher from seawater, with potential impacts to 55% of aquatic species in Asia estimated from chronic species sensitivity distribution (SSD). The concentration endangering only 5% of seawater species (HC5) was estimated as 1.13 (0.05-21.19) µg L-1. Estimated daily intakes revealed that overall, there are none to low health risks from aquatic product consumption, yet high risks are plausible to children with consumption patterns in the 95th percentile.