Impact of open manganese mines on the health of children dwelling in the surrounding area

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.

Heavy metals accumulation in the meat, kidney and liver of cattle, broilers and goats sold in Quetta, northwestern city of Balochistan, Pakistan

1. It was assumed that the concentrations of arsenic (As), chromium (Cr), cobalt (Co), lead (Pb), manganese (Mn) and mercury (Hg) in the meat, kidney and liver of cattle, broilers and goats within Quetta city potentially exceeded the permissible limits for heavy metal content. Risk assessment of these heavy metals on human health were estimated based on daily intake (EDI), target hazard quotient (THQ) and hazard index (HI).2. Samples of the meat, liver and kidney of cattle, broilers and goats were collected from butcher shops and slaughterhouses in 20 different areas of Quetta city. Overall, 180 samples were analysed, each for six heavy metals. After acid digestion of meat samples, heavy metals analysis was carried out via atomic absorption spectroscopy.3. The results varied in levels depending upon the species and organ type. The average concentrations of As, Pb and Hg were within the established reference limits of the Australia New Zealand Food Authority (ANZFA 2015) and the European Commission (EC, 2006), although some samples exceeded these limits. Compared with the kidney and meat, the liver was the primary tissue for Cr, Pb and Hg bioaccumulation. Metals concentration were mostly within the normal range in samples from cattle and goats, while the Mn concentration was elevated in broilers.4. The estimated daily intake (EDI) revealed that the intake of As, Co, Pb and Hg was mainly derived from goat and cattle products, whereas broiler samples were more contaminated with Cr and Mn. The EDIs of Cr and Hg in adults exceeded the oral reference dose, referring to potential adverse effects. The EDIs for Co and Mn were low, suggesting that additional intake sources were necessary. Except for As, none of the determined elements had a target hazard quotient (THQ) above 1.

The adverse effects of mining pollutants on oral mucosa in Bellary district: A clinical and genotoxicity study

Background

The Bellary district in Karnataka, rich in mineral resources, is a major mining industry, but prolonged exposure to mining can lead to health hazards. The study aims to assess the genotoxic impact of mining pollutants on mine workers using the micro-nucleus (MN) assay.

Setting and Design

Cross-sectional study.

Materials and Methods

A total of 250 individuals (198 males and 52 females) working in mining areas were examined, and their oral findings were recorded in a proforma. For the micro-nucleus assay, buccal smears from 30 individuals working in mining areas with habits, 30 individuals working in mining areas without habits, and 30 individuals residing in non-mining areas (control group) were selected. Smears were stained with Giemsa stain to identity and quantify the MNs.

Results

The frequency of oral mucosal problems among 250 persons working in mining regions was 170 (68.0%) with no oral mucosal conditions, 79 (32.6%) with oral mucosal conditions, 25 (10%) with leukoplakia, 1 (0.4%) with lichen planus, and 8 (3.2%) with ulcerations. Acute necrotising gingivitis was reported in one person (0.4%), candidiasis in two (0.8%), abscess in two (0.8%), OSMF in 39 (15.6%), and oral cancer in two (0.8%). The mean MN count was 2.40 + 1.57 in mine employees with habits, 2.18 + 1.25 in mine workers without habits, and 1.40 + 0.55 in normal healthy controls.

Conclusion

Reduced occupational health risks brought on by exposure to mining contaminants require protective measures. After being exposed to mining pollutants, exfoliated buccal mucosal cells can be examined for genotoxicity.

Epidemiological evidence for the effect of environmental heavy metal exposure on the immune system in children

Heavy metals exist widely in daily life, and exposure to heavy metals caused by environmental pollution has become a serious public health problem worldwide. Due to children's age-specific behavioral characteristics and imperfect physical function, the adverse health effects of heavy metals on children are much higher than in adults. Studies have found that heavy metal exposure is associated with low immune function in children. Although there are reviews describing the evidence for the adverse effects of heavy metal exposure on the immune system in children, the summary of evidence from epidemiological studies involving the level of immune molecules is not comprehensive. Therefore, this review summarizes the current epidemiological study on the effect of heavy metal exposure on childhood immune function from multiple perspectives, emphasizing its risks to the health of children's immune systems. It focuses on the effects of six heavy metals (lead (Pb), cadmium (Cd), arsenic (As), mercury (Hg), nickel (Ni), and manganese (Mn)) on children's innate immune cells, lymphocytes and their subpopulations, cytokines, total and specific immunoglobulins, and explores the immunotoxicological effects of heavy metals. The review finds that exposure to heavy metals, particularly Pb, Cd, As, and Hg, not only reduced lymphocyte numbers and suppressed adaptive immune responses in children, but also altered the innate immune response to impair the body's ability to fight pathogens. Epidemiological evidence suggests that heavy metal exposure alters cytokine levels and is associated with the development of inflammatory responses in children. Pb, As, and Hg exposure was associated with vaccination failure and decreased antibody titers, and increased risk of immune-related diseases in children by altering specific immunoglobulin levels. Cd, Ni and Mn showed activation effects on the immune response to childhood vaccination. Exposure age, sex, nutritional status, and co-exposure may influence the effects of heavy metals on immune function in children.

Manganese concentration in patients with encephalopathy following ephedrone use: a narrative review and analysis of case reports

BACKGROUND

Numerous case reports describe manganese encephalopathy in patients using ephedrone (methcathinone). The aim of this narrative review of case reports was to relate manganese ion concentrations in peripheral blood to the reported neurological deficits.

METHODS

International databases, including Thomson (Web of Knowledge), PubMed/Medline, Science Direct, Scopus and Google Scholar were searched for literature items published between 2007 and 2020, in which the authors measured the manganese concentration in patients taking ephedrone.

RESULTS

We identified 39 patients in two case series comprising of twenty-three and twelve patients, respectively, and four case reports meeting inclusion criteria. The study showed that 93% of them had elevated blood manganese concentration in relation to the accepted norm (>219 nmol/L), and the median was 364 nmol/L. The median duration of ephedrone use in individual groups of patients was approximately 48 months, and it did not show a relationship with the manganese concentration in the blood. A greater percentage of the people with manganese concentration higher than 250 nmol/L exhibited more severe gait, speech and handwriting disorders. The median duration of ephedrone withdrawal was a month in the group of people with the highest level of manganese ions (>500 nmol/L).

CONCLUSION

Manganese concentrations did not vary with the duration of ephedrone use.

Two Decades' Variation of Trace Elements in Bones of the Endangered East Asian Finless Porpoise (Neophocaena asaeorientalis sunameri) from the East China Sea, China

There has been increasing concern about trace element accumulation in finless porpoises over the past decades, while the long-term variation of its concentration has been little known. Since most soft tissues of porpoises in the past were not preserved until now, the bone tissue is the only ideal material available. Here, 27 East Asian finless porpoise bone samples collected from Nantong, the East China Sea during two periods (1984-1992 and 2009) were used to explore the temporal variation of nine typical elements' concentration (Fe, Mn, Cu, Ni, Hg, Cr, Pb, As, and Cd, dry weight). An upward trend for total trace element accumulation from 329.04 mg/kg in 1984-1992 to 1535.81 mg/kg in 2009 was found; this could have resulted from the increasing industrial development in the Nantong region. The Mn, Fe, and As levels increased significantly while the concentrations of Cd, Cu, and Pb significantly decreased. Generally, our results suggested that most trace elements posed low threats to East Asian finless porpoises' health during both periods, while elements Mn (2009), Ni (both periods), Fe (2009), and As (2009) posed a potentially higher health risk to porpoises. Thus, the trace element levels warrant concern and continuous monitoring.

Micronuclei, reproduction and child health

The current review looks for relationships between results from biomarker studies with micronucleus and health effects related to reproduction and children. In adults, an age related increase in MN is well known as well as associations with environmental exposures especially air pollution from traffic and smoking. Literature searches in PubMED and SCOPUS were performed with the following keywords reproduction, children, micronuclei, health effects. In total 162 studies were identified with the keyword children. Concerning children and health and children and environmental exposures, the titles and abstracts of a total of 162 publications were screened for language, inclusion of data from children and selected according to a study selection chart. 9 studies were included for children and health, and 21 studies for children and environmental exposures, with 12 in buccal cells and 9 in lymphocytes. The publications were read and included in tables if data on controls was available. MN frequencies were collected for peripheral blood lymphocytes (PBLs), reticulocytes or buccal cells (BC) and reported as Mean ± SD or Median (IQR). The Mean frequency Ratio, MRi, corresponding to the MN mean for study persons divided by MN mean for control persons was stated as reported in the publication or calculated by us from the data in the publication, where possible. Our systematic analysis revealed a number of positive associations of MN frequencies as a marker of increased health risk in relation to reproduction as well as child health. The majority of studies reported with children concerns exposures of children as well as maternal exposures and newborn health with MN as a biomarker of exposure. Exposure monitoring by MN as biomarker is also reported in studies of school children however most often not related to health effects. The MRis are found in ranges from 1 to 5.5 most studies around 2. As far as MN frequencies in children and exposure are concerned, the MRis range from 0.9 to 5.5, with a range from 1.3-4.9 for lymphocytes and from 1.5 to 2.5 in buccal cells, except for two studies with no differences found between cases and controls. Only one study is available for MRi calculation in reticulocytes with the value of 2.3. These data are supporting MN as a relevant biomarker for children health. However, the data is mostly from small studies with different protocol leaving out the possibility of metanalyses and even statistical comparisons among studies. The actual risk from elevated MNs in children waits large cohort studies with pooled datasets as performed with MN measured in adults. Introduction of buccal cells as non invasive alternative to lymphocytes is increasing and as with the lymphocytes standardised protocols are recommended to enable comparative studies and metaanalyses.