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Reproductive Toxicology (Elmsford, N.Y.) Jun 2024The primary route of mercury exposure for the general population is through consumption of contaminated seafood. There is a biological basis for an adverse effect of... (Review)
Review
The primary route of mercury exposure for the general population is through consumption of contaminated seafood. There is a biological basis for an adverse effect of mercury exposure on human fertility. The goal of this review was to evaluate the existing literature on the association between mercury and pregnancy, among men and women attempting to conceive with and without assisted reproductive technology (ART). Systematic searches were performed in PubMed, EMBASE, Scopus and Web of Science for papers published up to March 2023 with no early date restriction, only including studies with a biomarker measurement of mercury exposure. We identified 11 studies examining mercury and natural fertility and 12 studies examining mercury and outcomes of assisted reproduction (implantation or clinical pregnancy). The accumulated evidence provides some support for a null association between bodily mercury concentrations and natural fertility among women, however, a large proportion of studies did not report adjusted estimates or were extremely imprecise. The majority of studies of natural fertility were also cross-sectional in nature. There was no evidence for an inverse or null association between mercury and natural fertility among men, or mercury and ART outcomes among men or women. In spite of biological plausibility, the existing evidence includes studies that are imprecise and often conflicting and does not allow us to make definitive conclusions on the associations of mercury exposure with successful pregnancy. Additional, larger studies are warranted, especially among individuals with high concentrations of mercury exposure as these individuals may be underrepresented in the current literature.
PubMed: 38830454
DOI: 10.1016/j.reprotox.2024.108613 -
International Journal of Environmental... May 2022Mercury (Hg) is one of the most harmful metals and has been a public health concern according to the World Health Organization (WHO). Artisanal and small-scale gold... (Review)
Review
Mercury (Hg) is one of the most harmful metals and has been a public health concern according to the World Health Organization (WHO). Artisanal and small-scale gold mining (ASGM) is the world's fastest-growing source of Hg and can release Hg into the atmosphere, hydrosphere, and geosphere. Hg has been widely used in ASGM industries throughout Southeast Asia countries, including Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, and Thailand. Here, 16 relevant studies were systematically searched by performing the PRISMA flow, combining the keywords of "Hg", "ASGM", and relevant study areas. Mercury concentrations exceeding the WHO and United States Environmental Protection Agency guideline values were reported in environmental (i.e., air, water, and soil) and biomonitoring samples (i.e., plants, fish, and human hair). ASGM-related health risks to miners and nonminers, specifically in Indonesia, the Philippines, and Myanmar, were also assessed. The findings indicated severe Hg contamination around the ASGM process, specifically the gold-amalgamation stage, was significantly high. To one point, Hg atmospheric concentrations from all observed studies was shown to be extremely high in the vicinity of gold operating areas. Attentions should be given regarding the public health concern, specifically for the vulnerable groups such as adults, pregnant women, and children who live near the ASGM activity. This review summarizes the effects of Hg in Myanmar and other Southeast Asian countries. In the future, more research and assessment will be required to investigate the current and evolving situation in ASGM communities.
Topics: Animals; Environmental Pollution; Female; Gold; Humans; Mercury; Mining; Myanmar; Pregnancy; United States
PubMed: 35627826
DOI: 10.3390/ijerph19106290 -
Journal of Environmental Management Jan 2021The harm from mercury pollution to human health and the environment has long been known. In recent years, the combination of industrial activities and long-term... (Review)
Review
The harm from mercury pollution to human health and the environment has long been known. In recent years, the combination of industrial activities and long-term atmospheric transport has resulted in a sustained increase in mercury concentrations in soils. However, soil remediation and mercury-contaminated soil management in China are still in its infancy, and there is ample space for the development of related research. We systematically reviewed several pertinent topics and found that soil mercury pollution around mines and industrial soil in China is the most serious. The highest mercury content is found in the soil around the Tongren mercury mine in Guizhou Province and the thermometer factories. The average content of soil mercury is similar to that of atmospheric mercury emission in China. Mercury content in soil gradually decreases from the southeast to the northwest. In order to repair the mercury-contaminated soil, solidification and stabilization technology have been developed in China and applied in the engineering of restoration. In the future, we will study more effective stabilizer materials and select plants highly rich in mercury, to develop low-cost and high-repair-rate remediation technology. China has also developed a series of policies, regulations, and regulatory documents to manage mercury pollution, such as the Agricultural Land Standard and the Construction Land Standard. Compared with other countries, the screening values for soil mercury in China are relatively low. China has also established control standards for methylmercury in soils of residential and industrial land. In addition, China has issued emission standards and control notices related to the mercury industry. However, there are still shortcomings in soil remediation technology and environmental management systems for mercury pollution in China. In the future, China will formulate standards according to local conditions and improve the responsibility mechanism, financial mechanism, and level of public participation.
Topics: China; Conservation of Natural Resources; Environmental Monitoring; Environmental Pollution; Humans; Mercury; Soil; Soil Pollutants
PubMed: 33069151
DOI: 10.1016/j.jenvman.2020.111442 -
Environmental Health Perspectives Jul 2018Body burden of mercury has been linked to hypertension in populations exposed to high mercury levels. (Meta-Analysis)
Meta-Analysis
BACKGROUND
Body burden of mercury has been linked to hypertension in populations exposed to high mercury levels.
OBJECTIVES
We summarized, extracted, and pooled the results of published studies that investigated mercury biomarkers and hypertension or blood pressure (BP) measurements to examine this potential relationship.
METHODS
We searched PubMed, Embase, and TOXLINE and selected studies according to defined inclusion criteria. Study quality was assessed by the Newcastle-Ottawa scale for cohort and case-control studies and the Quality Assessment Tool for cross-sectional studies. Study estimates were pooled using inverse-variance weighted random-effects models. Dose-response meta-analysis was performed with studies reporting hypertension and systolic BP for at least three mercury categories.
RESULTS
A total of 29 studies were included in the meta-analysis. The pooled odds ratio (OR) for hypertension, comparing the highest and lowest mercury exposure categories, was 1.35 [95% confidence interval (CI): 0.99, 1.83] for populations with hair mercury ≥2 μg/g in comparison with the OR of 1.12 (95% CI: 0.82, 1.52) for populations with hair mercury <2 μg/g. Positive associations were also observed for highest versus lowest mercury exposure categories on systolic and diastolic BP. Heterogeneity was observed for mercury species and exposure groups across different studies. Associations estimated using different mercury biomarkers generally agree with each other in the same study. A nonlinear dose-response relationship with an inflection point at 3 μg/g was identified, for both hypertension and systolic BP.
CONCLUSIONS
A significant positive association between mercury and hypertension and between mercury and BP was identified. The exposure dose is an important factor in determining the toxic effects of mercury on hypertension. https://doi.org/10.1289/EHP2863.
Topics: Blood Pressure; Dose-Response Relationship, Drug; Environmental Exposure; Environmental Pollutants; Humans; Hypertension; Mercury; Odds Ratio; Prevalence; Proportional Hazards Models
PubMed: 30073953
DOI: 10.1289/EHP2863 -
Environmental Pollution (Barking, Essex... Jan 2021Four most concerned heavy metal pollutants, arsenic, cadmium, lead, and mercury may share common mechanisms to induce metabolic syndrome (MetS). However, recent studies... (Review)
Review
Four most concerned heavy metal pollutants, arsenic, cadmium, lead, and mercury may share common mechanisms to induce metabolic syndrome (MetS). However, recent studies exploring the relationships between MetS and metal exposure presented inconsistent findings. We aimed to clarify the relationship between heavy metal exposure biomarkers and MetS using a meta-analysis and systematic review approach. Literature search was conducted in international and the Chinese national databases up to June 2020. Of selected studies, we extracted the relevant data and evaluated the quality of each study's methodology. We then calculated the pooled effect sizes (ESs), standardized mean differences (SMDs), and their 95% confidence intervals (CIs) using a random-effect meta-analysis approach followed by stratification analyses for control of potential confounders. Involving 55,536 participants, the included 22 articles covered 52 observational studies reporting ESs and/or metal concentrations on specific metal and gender. Our results show that participants with MetS had significantly higher levels of heavy metal exposure [pooled ES = 1.16, 95% CI: 1.09, 1.23; n = 42, heterogeneity I = 75.6%; and SMD = 0.22, 95% CI: 0.15, 0.29; n = 32, I = 94.2%] than those without MetS. Pooled ESs in the subgroups stratified by arsenic, cadmium, lead, and mercury were 1.04 (95% CI: 0.97, 1.10; n = 8, I = 61.0%), 1.10 (0.95, 1.27; 11, 45.0%), 1.21 (1.00, 1.48; 12, 82.9%), and 1.26 (1.06, 1.48; 11, 67.7%), respectively. Pooled ESs in the subgroups stratified by blood, urine, and the other specimen were 1.22 (95% CI: 1.08, 1.38; n = 26, I = 75.8%), 1.06 (1.00, 1.13; 14, 58.1%), and 2.41 (1.30, 4.43; 2, 0.0%), respectively. In conclusion, heavy metal exposure was positively associated with MetS. Further studies are warranted to examine the effects of individual metals and their interaction on the relationship between MetS and heavy metals.
PubMed: 33486246
DOI: 10.1016/j.envpol.2021.116480 -
Journal of Environmental Health Science... Dec 2020Exposure to mercury is an important risk to dentists health. The aim of the present study was to assess the pooled mean mercury level (MML) in the urine, blood, nail,... (Review)
Review
Exposure to mercury is an important risk to dentists health. The aim of the present study was to assess the pooled mean mercury level (MML) in the urine, blood, nail, and hair of Iranian dentists (IDs) through the meta-analysis technique. Comprehensive and systematic searches were performed in main local databases including SID, Magiran, Iran medex, and ISC as well as internationally available databases including Embase, PubMed and Scopus for all the relevant studies up to 2018. In order to prevent bias in this study and identify eligible studies, various steps of the study was performed independently by two researchers. Out of 13 studies in the meta-analysis process which included 1499 IDs, the mean of the mercury level in the urine, nail, and blood was estimated to be 6.29 (95% CI: 2.61-9.97, I-square: 62.7%, P: 0.006), 3.54 (95% CI: 2.81-4.28, I-square: 0.0%, P: 0.968), 11.20 (95% CI: 2.28-20.13, I-square: 59.9%, P: 0.082), respectively. The mean mercury level (MML) in the biological samples of IDs was higher than the standard of World Health Organization (WHO). So, in accordance with Article 10 of the European Union Regulations (EUR), in the context of the Minamata Convention (MC) on Dental Amalgam (DA), in order to avoid the dangers of mercury exposure in dentists, it is necessary for Iran and other countries to approve laws and to implement a national plan to reduce mercury levels and replace the appropriate materials.
PubMed: 33312669
DOI: 10.1007/s40201-020-00558-w -
Annals of Indian Academy of Neurology 2022Stroke is the second largest cause of mortality (WHO 2014) and long-lasting disability worldwide. Many risk factors are associated with stroke, such as age, gender,...
BACKGROUND
Stroke is the second largest cause of mortality (WHO 2014) and long-lasting disability worldwide. Many risk factors are associated with stroke, such as age, gender, chronic illnesses, cardiovascular disease, lifestyle, and smoking. With global industrialization, the roles of environmental contaminants and their association with stroke are still unclear and have attracted much more attention.
MATERIALS AND METHODS
We conducted a systematic review on the environmental toxic metal contaminants and the risk of ischemic stroke. A comprehensive literature search was carried out till June 30, 2021 from databases such as PubMed, Science Direct, Embase, and Scopus. The quality of all the articles which met our inclusion criteria was assessed using Newcastle-Ottawa scaling, and four eligible studies were included for our systematic review.
RESULTS
The serum and urine cadmium concentrations were positively associated with the risk of ischemic stroke. There was an inverse association of serum and urine concentrations of mercury (Hg), serum concentration of gold and cerium with ischemic stroke, and the serum and urine concentrations of lead (Pb) had no association with ischemic stroke risk.
CONCLUSION
The study showed strong associations between heavy metals and ischemic stroke, but more studies are required to prove the associations.
PubMed: 36911452
DOI: 10.4103/aian.aian_530_22 -
Journal of Environmental Health Science... Jun 2023Heavy metals and metalloids are recognized as environmental threats, which are considered highly toxic and carcinogenic. Epidemiologically, their association with...
PURPOSE
Heavy metals and metalloids are recognized as environmental threats, which are considered highly toxic and carcinogenic. Epidemiologically, their association with leukemia is under debate. We aim to clarify the association between the heavy metal(loid)s in serum and leukemia via a systematic review and meta-analysis.
METHODS
We searched PubMed, Embase, Google Scholar, and CNKI (China National Knowledge Infrastructure) databases for all related articles. The standardized mean difference and its 95% confidence interval was used to evaluate the association of leukemia with heavy metal(loid)s in serum. The statistical heterogeneity among studies was assessed with the Q-test and statistics.
RESULTS
Among 4,119 articles related to metal(loid)s and leukemia, 21 studies met our inclusion criteria, which are all cross-sectional studies. These 21 studies involved 1,316 cases and 1,310 controls, based on which we evaluate the association of heavy metals/metalloids in serum with leukemia. Our results indicated positive differences for serum chromium, nickel, and mercury in leukemia patients, while a negative difference for serum manganese in acute lymphocytic leukemia (ALL).
CONCLUSION
Our results suggested an elevated trend of serum chromium, nickel, and mercury concentrations in leukemia patients while descending trend of serum manganese concentration in ALL patients. The result of sensitivity analysis between lead, cadmium, and leukemia and publication bias of association between chromium and leukemia also needed attention. Future research work may focus on the dose-response relationship between any of these elements and the leukemia risks, and further elucidation of how these elements are related to leukemia may shed light on the prevention and treatment of leukemia.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s40201-023-00853-2.
PubMed: 37159736
DOI: 10.1007/s40201-023-00853-2 -
Biological Trace Element Research Nov 2022It has been reported that heavy metals have adverse effects on the immune system. However, the relationship between heavy metal exposure and allergic outcomes remains... (Meta-Analysis)
Meta-Analysis Review
It has been reported that heavy metals have adverse effects on the immune system. However, the relationship between heavy metal exposure and allergic outcomes remains unclear. This systematic review was conducted to examine whether heavy metal exposure is associated with allergic outcomes during childhood. We performed a systematic search of all relevant articles in Web of Science, EMBASE, and PubMed, from inception through to November 2020. We used odds ratio (OR) and the standard mean differences (SMDs) with 95% confidence intervals (CIs) to present estimates from individual studies. In addition, random-effects meta-analysis was used to pool the data. We also conducted the meta-regression and subgroup analysis to explore potential sources of heterogeneity. After duplicate removal, we finally included 35 articles in the systematic review and meta-analysis from an initial 11,181 articles. The overall results showed that copper (Cu) was associated with asthma (pooled SMD = 1.50, 95% CI = 0.13-2.86); in the subgroup analysis, the results indicated that lead (Pb) was associated with asthma (pooled OR = 6.27, 95% CI = 2.24-17.56), and Cu and Pb were connected with atopic dermatitis (SMD = - 1.05, 95% CI = - 1.45 to - 0.65; SMD = 5.68, 95% CI = 5.05-6.32), respectively. Mercury (Hg) was associated with atopic dermatitis (pooled OR = 1.13, 95% CI = 1.04-1.22) and wheeze (OR = 1.20, 95% CI = 1.05-1.37). The meta-analysis results indicate that Cu might be connected with childhood asthma, but not with other allergic diseases; Hg and Pb may have no association with allergic diseases during childhood. Given some limits observed in the current studies, more prospective cohort studies are still needed to verify our findings. Review registration: PROSPERO CRD42020222167.
Topics: Asthma; Child; Copper; Dermatitis, Atopic; Humans; Lead; Mercury; Metals, Heavy; Prospective Studies
PubMed: 35006554
DOI: 10.1007/s12011-021-03070-w -
Skin Appendage Disorders Oct 2018There are a number of toxic agents that can cause alopecia. In this review we summarize the known substances that cause alopecia as one of the clinical signs of overdose... (Review)
Review
IMPORTANCE/OBJECTIVE
There are a number of toxic agents that can cause alopecia. In this review we summarize the known substances that cause alopecia as one of the clinical signs of overdose or toxicity.
EVIDENCE REVIEW
A search was conducted using PubMed, EMBASE, and Cochrane for studies describing hair loss of any type as a result of exposure to or ingestion of a toxic agent. The search yielded 856 articles, with 47 studies included in this review.
FINDINGS
Agents with the strongest evidence of association to alopecia include thallium, mercury, selenium, and colchicine. Agents with described incidents include boric acid, arsenic, vitamin A, botulinum toxin, , and the synthetic opioid MT-45.
CONCLUSIONS AND RELEVANCE
Numerous toxic agents have been implicated in alopecia, and the strength of evidence behind each agent varies. Toxic levels of thallium and colchicine have long been established to cause alopecia, as compared to agents such as botulinum toxin A and synthetic recreational drugs which have less literature describing their links to alopecia and will need further investigation to characterize their relationships to hair loss. Knowledge of typical presentations of hair loss will aid in the development of a differential diagnosis for patients presenting with alopecia.
PubMed: 30410891
DOI: 10.1159/000485749