Evaluation of trace elements pollution in deposited dust on residential areas and agricultural lands around Pb/Zn mineral areas using modified pollution indices

Spatial distribution and the ecological risks posed by heavy metals and total petroleum hydrocarbons (TPHs) in the sediments of mangrove and coral habitats of Northeast Persian Gulf

BACKGROUND

Heavy metals and total petroleum hydrocarbons (TPHs) are important pollutants in the aquatic ecosystem, and their long-term resistance, bio-accumulation, and bio-magnification during the food chain may cause adverse ecological and health risks.

METHODS

In here, the distribution and risk assessment of six heavy metals Cd, Pb, Ni, Cu, Zn, Cr, and TPHs were performed in the sediments of 32 regions situated in two mangroves (Tiab and Azini estuaries, Hara Mangrove forest protected area) and coral habitats (Larak and Hengam Islands) in Northeast of the Persian Gulf during 2020-2021. An atomic absorption device was used to determine the concentrations of heavy metals. Ecological risk of heavy metals is assessed through indices contamination factor (CF), contamination degree (CD), modified contamination degree (MCD), pollution load index (PLI), potential ecological risk index (PERI), and geoaccumulation index (Igeo). The spatial distribution of heavy metals was mapped through the inverse distance weighting (IDW) method in ArcMap.

RESULTS

The concentration of heavy metals indicated significant differences in spatial distribution. The maximum concentration of Cd 1.64 ± 0.001, Cr 18.41 ± 0.41 and Cu 40.5 ± 0.28 µg/g was observed at the regions situated in the Hara Mangrove forest protected area. Azini estuary had the maximum value of Zn 94.61 ± 30.74 and TPHs 4.47 ± 1.93 µg/g and finally, the highest value of concentration Ni 135.22 ± 1.85 µg/g and Pb 17.87 ± 2.17 g/gµ was found in Tiab estuary. The studied regions in the Tiab estuary and Hara Mangrove forest protected area were more contaminated than others and had considerable risks of Ni and Cd. Average ecological indices indicated the sediments of these areas especially Tiab, Hara Mangrove forest protected area, and Azini are moderately to considerably contaminated with Cd and Ni. Tiab was identified as the most contaminated area and all stations except Hengam Island were exposed to considerable ecological risks. Cadmium was found to be the riskiest heavy metal in the investigated region. The distribution of TPHs indicated there is no pollution of TPHs in the region. In all studied stations, the PELq (Toxicity of TPHs) and CF values showed the absence of potential risks of TPHs in sediments.

CONCLUSIONS

The findings indicated considerable contamination of Cd and Ni in the mangrove areas, especially Tiab, and it seems necessary to identify, manage, and control possible sources of contamination.

Assessment of environmental and health risks of potentially toxic elements associated with desert dust particles affected by industrial activities in Isfahan metropolitan

Dust particles and their associated compounds can adversely affect human health and ecosystems. The aim of this study was to investigate the concentration, health, and ecological risks of selected potentially toxic elements (e.g. Pb, Cd, Cr, Co, Cu, Zn, V, Ni, and As) bound to air particles generated by dust storms in the Sejzi plain desert area within the industrial district of Isfahan metropolitan, Iran. The enrichment factor revealed the highest values for Zn, Pb, and Cd which among them Zn showed the highest value (8.1) with the potential source of industrial activities confirmed by the integrated pollution index, accumulation coefficient, and ecological risk index. Regarding health risk analysis (non-cancer and cancer risks) the elements including Co, As, and Cr showed a significant risk for adults and children across all seasons. It's concluded that mitigation of air particles originated from both natural and industrial activities is necessary to reduce their relevant risks to human being and ecosystems in the region.

Monitoring the temporal variations of plant stress using the air pollution tolerance index in the Sejzi industrial area (Isfahan, Iran)

The objective of this study was to screen air pollution-induced stress in some plant species in the Sejzi industrial region (Isfahan, Iran). An assessment of APTI and other physiological and biochemical features of significant species in the area was conducted across three seasons: spring, summer, and autumn. The physiological and biochemical factors of the following species were evaluated: Limonium persicum, Atriplex lentiformis, Nitraria schoberi, Haloxylon persicum, Tamarix hispida, Zygophyllum atriplicoides, Karelinia caspica, and Prosopis farcta. The physiological factors assessed included acidity and relative humidity content, while the biochemical factors assessed included proline, sugar, ascorbic acid, and total chlorophyll. Subsequently, a thorough evaluation was carried out on the species under investigation to ascertain their biomonitors' capabilities and APTI. The study findings indicated that the species P. farcta, N. schoberi, and K. caspica consistently had high APTI values during the spring, autumn, and summer seasons, classifying them as tolerant plant species. Conversely, the observed traits showed significant fluctuations across the seasons. The investigation's findings indicate that the species L. persicum, N. schoberi, and K. caspica exhibit higher annual averages of chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid compared to other species. The examination of the annual variation in the tolerance levels of plant species to pollution ranked from highest to lowest was as follows: N. schoberi, P. farcta, K. caspica, Z. atriplicoides, H. persicum, T. hispida, L. persicum, and A. lentiformis. Moreover, based on the annual average, the primary determinants that impact the APTI in the species being studied include ascorbic acid (35%), leaf acidity (19%), total chlorophyll content (35%), and relative humidity content (69%). Furthermore, a distinct and significant correlation was found between proline and sugar levels and the annual APTI values. Additionally, the species P. farcta had the highest API compared to other species. The study revealed the high potential of some plant species against air pollution induced stress which can be used in air and dust pollution management in the region.

Occupational, environmental, and toxicological health risks of mining metals for lithium-ion batteries: a narrative review of the Pubmed database

BACKGROUND

The global market for lithium-ion batteries (LIBs) is growing exponentially, resulting in an increase in mining activities for the metals needed for manufacturing LIBs. Cobalt, lithium, manganese, and nickel are four of the metals most used in the construction of LIBs, and each has known toxicological risks associated with exposure. Mining for these metals poses potential human health risks via occupational and environmental exposures; however, there is a paucity of data surrounding the risks of increasing mining activity. The objective of this review was to characterize these risks.

METHODS

We conducted a review of the literature via a systematic search of the PubMed database on the health effects of mining for cobalt, lithium, manganese, and nickel. We included articles that (1) reported original research, (2) reported outcomes directly related to human health, (3) assessed exposure to mining for cobalt, lithium, manganese, or nickel, and (4) had an available English translation. We excluded all other articles. Our search identified 183 relevant articles.

RESULTS

Toxicological hazards were reported in 110 studies. Exposure to cobalt and nickel mining were most associated with respiratory toxicity, while exposure to manganese mining was most associated with neurologic toxicity. Notably, no articles were identified that assessed lithium toxicity associated with mining exposure. Traumatic hazards were reported in six studies. Three articles reported infectious disease hazards, while six studies reported effects on mental health. Several studies reported increased health risks in children compared to adults.

CONCLUSIONS

The results of this review suggest that occupational and environmental exposure to mining metals used in LIBs presents significant risks to human health that result in both acute and chronic toxicities. Further research is needed to better characterize these risks, particularly regarding lithium mining.

Pollution characteristics and probabilistic health risk of potentially hazardous elements in soils near a typical coal mine in Panzhihua City, Southwest China

This study first assessed the pollution characteristics and probabilistic health risks of potentially hazardous elements (PHEs) in soils from the Dabaoding coal mining area in southwest China using Monte Carlo simulation. Experimental results showed that Cd was moderately enriched in soils, while Ni, Cr, and V were slightly enriched. However, the geoaccumulation index (I_geo) illustrated that the coal mining area had a low level of Cd pollution. PHEs produced a very high ecological risk to soils in the coal mining area, whereas Cd showed the highest contribution (82.56%). The mean hazard index of all soil PHEs was 7.45E - 02 and 4.18E - 01 for local adults and children, respectively, all of which were obviously lower than the maximum acceptable level of 1.0. However, Monte Carlo simulation analysis indicated that 1.08% of noncarcinogenic risk values for local children still exceeded the maximum acceptable level. Additionally, 10.84% and 18.40% of the total carcinogenic risk values for local adults and children, respectively, exceeded the threshold of 1E - 04. Indeed, Cr and Ni had the highest contributions to noncarcinogenic and carcinogenic risks, respectively. These findings suggest that Cd, Cr, and Ni should be identified as priority pollutants in coal mining areas. This study also provides valuable implications for policy-makers and environmental engineers, proposing efficient policies for better soil pollution control and remediation strategies in coal mining areas.