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Annals of Translational Medicine Jan 2023Recent studies have shown that the relationship between mercury exposure and diabetes is controversial. The aim of this study is to determine the relationship between...
BACKGROUND
Recent studies have shown that the relationship between mercury exposure and diabetes is controversial. The aim of this study is to determine the relationship between mercury exposure and diabetes using a systematic review and meta-analysis approach.
METHODS
We systematically searched PubMed, Web of Science, Cochrane, and Embase databases for cross-sectional, case-control, or cohort studies assessing the correlation between mercury exposure and diabetes in any population. Details of each included study were extracted using a pre-designed Excel spreadsheet. Quality assessment of cohort and case-control studies used the Newcastle-Ottawa Scale (NOS), whereas cross-sectional studies were assessed by the Agency for Healthcare Research and Quality (AHRQ) scale. Meta-analyses were performed using random-effects models to calculate the pooled odds ratio (OR), standardized mean difference (SMD), and their 95% confidence intervals (CIs). Subgroup and sensitivity analyses were employed to assess heterogeneity sources. Begg's and Egger's tests were used to evaluate publication bias.
RESULTS
Our meta-analysis included 8 eligible articles, comprising a total of 40,891 subjects, reporting mercury OR and/or concentrations. Among the included studies, one was a case control, one was a cohort study, and the rest were cross-sectional studies. Two studies were rated as high quality and six as medium quality. The results revealed no link between mercury exposure and diabetes (OR: 1.11, 95% CI: 0.80, 1.55, n=6, I=73.7%; and SMD: 0.41, 95% CI: -0.32, 1.14, n=3, I=88.7%). In the stratified male and female subgroups, the pooled OR was 0.71 (95% CI: 0.57, 0.90, n=3, I=0.0%), 1.11 (95% CI: 0.69, 1.79, n=3, I=67.7%). The Begg's test results revealed no significant publication bias (P=0.06), but the Egger's test results did (P=0.013). The sensitivity analysis confirmed the stability of our results.
CONCLUSIONS
No significant relationship was observed between mercury and diabetes mellitus. However, more well-designed studies on mercury exposure and diabetes risk are still needed, particularly on the type of mercury (i.e., elemental, inorganic, and organic), exposure time and dose, type of biological specimen, and the population's sex and age.
PubMed: 36819500
DOI: 10.21037/atm-22-6404 -
Revista Brasileira de Ginecologia E... Dec 2022The present review aimed to synthesize the evidence regarding mercury (Hg) exposure and hypertensive disorders of pregnancy (HDP).
OBJECTIVE
The present review aimed to synthesize the evidence regarding mercury (Hg) exposure and hypertensive disorders of pregnancy (HDP).
DATA SOURCES
The PubMed, BVS/LILACS, SciELO and UFRJ's Pantheon Digital Library databases were systematically searched through June 2021.
STUDY SELECTION
Observational analytical articles, written in English, Spanish, or Portuguese, without time restriction.
DATA COLLECTION
We followed the PICOS strategy, and the methodological quality was assessed using the Downs and Black checklist.
DATA SYNTHESIS
We retrieved 77 articles, of which 6 met the review criteria. They comprised 4,848 participants, of which 809 (16.7%) had HDP and 4,724 (97.4%) were environmentally exposed to Hg (fish consumption and dental amalgam). Mercury biomarkers evaluated were blood (four studies) and urine (two studies). Two studies found a positive association between Hg and HDP in the group with more exposure, and the other four did not present it. The quality assessment revealed three satisfactory and three good-rated studies (mean: 19.3 ± 1.6 out 28 points). The absence or no proper adjustment for negative confounding factor, such as fish consumption, was observed in five studies.
CONCLUSION
We retrieved only six studies, although Hg is a widespread toxic metal and pregnancy is a period of heightened susceptibility to environmental threats and cardiovascular risk. Overall, our review showed mixed results, with two studies reporting a positive association in the group with more exposure. However, due to the importance of the subject, additional studies are needed to elucidate the effects of Hg on HDP, with particular attention to adjusting negative confounding.
Topics: Humans; Pregnancy; Female; Animals; Mercury; Hypertension, Pregnancy-Induced; Maternal Exposure; Biomarkers
PubMed: 36580940
DOI: 10.1055/s-0042-1760215 -
Ecotoxicology and Environmental Safety Jan 2023Risk assessment of heavy metals is critical in controlling and preventing risks of foodborne diseases. Fish can be used as bioindicators for exposure to potential toxic... (Review)
Review
Risk assessment of heavy metals is critical in controlling and preventing risks of foodborne diseases. Fish can be used as bioindicators for exposure to potential toxic elements (PTEs), which can represent potential risks for humans. The long Iranian coastline and three major fishery regions in the country, including the northern (Caspian Sea) and southern (Persian Gulf and Gulf of Oman) seas as well as inland waters and aquacultures (rivers, dams, wetlands and fish farms) have made Iran a large producer of fish. In the first step of the present study, data collection and report of PTEs in fish from the three fishery regions (2010-2022) were carried out. In the second step, health risks were assessed using Monte Carlo simulation in child and adult consumers. The average concentrations of Cd, Hg and Pb for the northern sea, southern sea, and inland waters and aquacultures were 0.273, 0.249, 1.077; 0.430, 0.423, 1.182; and 1.387, 0.232, 1.703 μg/g per dry weight, respectively. Based on the target hazard quotient results, Hg intake of Iranian children from all the three fishery regions was more than 1, which was alarming. In the adult age group, southern sea fish consumers were at risk of Hg adverse health effects. Moreover, Cd included the highest carcinogenic risk of toxic elements in fish from the three fishery regions of Iran. Estimation of THQ, HI, ILCR and EDI revealed that consumption of fish might induce health complexities for the consumers in Iran. Moreover, Iranians from northern and southern regions of the country consumed further seafood due to the availability of high seafood sources in these regions. Hence, various indices must be used for the risk assessment of general human health. Due to the high risks of carcinogenicity/non-carcinogenicity estimated in the risk assessment, consumption of fish by infants and pregnant women must critically be assessed.
Topics: Adult; Animals; Child; Female; Humans; Infant; Pregnancy; Cadmium; Environmental Monitoring; Fishes; Food Contamination; Indian Ocean; Iran; Mercury; Metals, Heavy; Risk Assessment
PubMed: 36508819
DOI: 10.1016/j.ecoenv.2022.114349 -
Environmental Health Perspectives Nov 2022The Minamata Convention on Mercury (Article 4) prohibits the manufacture, import, or export of skin-lightening products containing mercury concentrations above .... (Review)
Review
BACKGROUND
The Minamata Convention on Mercury (Article 4) prohibits the manufacture, import, or export of skin-lightening products containing mercury concentrations above . However, there is a lack of knowledge surrounding the global prevalence of mercury-added skin-lightening products.
OBJECTIVE
The objective of this study was to increase our understanding of worldwide human mercury exposure from skin-lightening products.
METHODS
A systematic search of peer-reviewed scientific literature was performed for relevant articles in four databases (PubMed, Web of Science Core Collection, Scopus, and TOXLINE). The search strategy, eligibility criteria, and data-extraction methods were established . The search identified 2,303 unique scientific articles, of which 41 were ultimately deemed eligible for inclusion after iterative screens at the title, abstract, and whole-text levels. To facilitate data extraction and synthesis, all papers were organized according to four data groups ) "Mercury in products," ) "Usage of products," ) "Human biomarkers of exposure," and ) "Health impacts."
RESULTS
This review was based on data contained in 41 peer-reviewed scientific papers from 22 countries worldwide published between 2000 and 2022. In total, we captured mercury concentration values from 787 skin-lightening product samples [overall pooled central median mercury level was ; interquartile range (IQR): 0.02-5.9] and 1,042 human biomarker measurements from 863 individuals. We also synthesized usage information from 3,898 individuals and self-reported health impacts associated with using mercury-added products from 832 individuals.
DISCUSSION
This review suggests that mercury widely exists as an active ingredient in many skin-lightening products worldwide and that users are at risk of variable and often high exposures. These synthesized findings identify data gaps and help increase our understanding of the health risks associated with the use of these products. https://doi.org/10.1289/EHP10808.
Topics: Humans; Mercury; Biomarkers
PubMed: 36367779
DOI: 10.1289/EHP10808 -
Foods (Basel, Switzerland) Oct 2022With the objective of evaluating the quality parameters of raw milk in Ecuador between 2010 and 2020, a systematic review and meta-analysis of 73 studies on raw milk...
With the objective of evaluating the quality parameters of raw milk in Ecuador between 2010 and 2020, a systematic review and meta-analysis of 73 studies on raw milk produced in different regions of Ecuador was performed. Under the random effects model, effect size and heterogeneity were determined vs. climatic region both among analyses and studies, with Cochran’s Q, I2 and Tau (π) statistics. For all the variables, it was observed that there was great heterogeneity (I2 > 90%) among the studies; additionally, it was found that climatic region had an influence only among the variables arsenic, mercury, pH and total solids, and it was greater in the coastal region than the Inter-Andean region. The mean values of the physicochemical characteristics of the milk (titratable acidity, ash, cryoscopy, fat, lactose, pH, protein, non-fat solids and total solids) in the great majority of these studies were within the range allowed by Ecuadorian regulations. As for the hygienic quality of raw milk (total bacterial count, somatic cell count and presence of reductase), although the mean values were within those determined by local legislation, it should be noted that the range established by Ecuadorian regulations is relatively much higher compared to other regulations, which possibly means that there is a high presence of bacteria and somatic cells in raw milk. Finally, the presence of several adulterants (added water) and contaminants (AFM1, antibiotics and heavy metals) was confirmed in the milk, in addition to other substances such as eprinomectin, zearalenone and ptaquilosides, whose presence can be very dangerous, because they can be hepatotoxic, immunotoxic and even carcinogenic. In conclusion, there is great variability among the studies reviewed, with the physicochemical characteristics being the most compliant with Ecuadorian legislation; the hygienic characteristics, adulterants and contaminants of raw milk require greater attention by producers and local authorities, so that they do not harm the health of consumers and the profitability of producers in Ecuador.
PubMed: 36359964
DOI: 10.3390/foods11213351 -
Frontiers in Pediatrics 2022Mechanistic studies show that heavy metals interfere with the hematopoietic system by inhibiting key enzymes, which could lead to anemia. However, the link between...
BACKGROUND
Mechanistic studies show that heavy metals interfere with the hematopoietic system by inhibiting key enzymes, which could lead to anemia. However, the link between children's exposure and red blood cell (RBC) parameters has been inconsistent. We aimed to summarize evidence on human studies exploring the association between exposure to lead, mercury, cadmium, arsenic, and chromium VI and RBC parameters in children.
METHODS
Following the PRISMA guidelines, we searched PubMed, Scopus, and Web of Science databases for studies published between January 2010 and April 2022. Eligible papers included human observational studies that directly assessed exposure (internal dose) to the heavy metals under study and RBC parameters in participants aged ≤ 18 years. We excluded studies using hospital-based samples. Study quality was assessed using the National Institutes of Health's Quality Assessment Tools for Cohort and Cross-Sectional Studies. We synthesized the evidence using vote counting based on the direction of the relationship.
RESULTS
Out of 6,652 retrieved papers, we included a total of 38 (33 assessing lead, four mercury, two cadmium, and two arsenic; chromium VI was not assessed in any included paper). More than half of the studies were conducted in Asia. We found evidence of a positive relationship between lead concentration and hemoglobin (proportion of studies reporting negative relationships = 0.750; 95% Confidence Interval (CI) 0.583, 0.874) and mean corpuscular hemoglobin (0.875; 95% CI 0.546, 0.986), and a positive relationship with red cell distribution width (0.000; 95%CI 0.000, 0.379). When considering only good-quality studies (24% of the Pb studies), only the relationship with hemoglobin levels remained (0.875; 95% CI: 0.546, 0.986).
CONCLUSION
We found evidence of a negative relationship between lead concentration and hemoglobin and mean corpuscular hemoglobin and of a positive relationship with red cell distribution width in children. We also identified a need to conduct more studies in European countries. Future studies should use standardized practices and make efforts to increase study quality, namely by conducting comprehensive longitudinal studies. Our findings support the need to take further actions to limit heavy metal exposure during childhood.
PubMed: 36275050
DOI: 10.3389/fped.2022.921239 -
International Journal of Environmental... Sep 2022Electronic waste (e-waste) recycling releases mercury (Hg) into the environment, though to our knowledge Hg levels at such sites have yet to be examined on a worldwide... (Meta-Analysis)
Meta-Analysis Review
Electronic waste (e-waste) recycling releases mercury (Hg) into the environment, though to our knowledge Hg levels at such sites have yet to be examined on a worldwide basis. A systematic review of scientific studies was conducted to extract, analyze, and synthesize data on Hg levels in e-waste products, environments near recycling sites, and in people. Data were extracted from 78 studies from 20 countries, and these included Hg levels in 1103 electrical and electronic products, 2072 environmental samples (soil, air, plant, food, water, dust), and 2330 human biomarkers (blood, hair, urine). The average Hg level in products was 0.65 μg/g, with the highest levels found in lamps (578 μg/g). Average soil and sediment Hg levels (1.86 μg/g) at e-waste sites were at least eight times higher than at control sites. Average urinary Hg levels (0.93 μg/g creatinine) were approximately two-fold higher among e-waste workers versus control groups. Collectively, these findings demonstrate that e-waste recycling may lead to Hg contamination in environments and human populations in close proximity to processing sites. These findings contribute to a growing knowledge base of mercury exposure through diverse source-exposure pathways, and the work has potential policy implications in the context of the Minamata Convention.
Topics: Biomarkers; Creatinine; Dust; Electronic Waste; Environmental Monitoring; Humans; Mercury; Soil; Waste Products; Water Pollutants, Chemical
PubMed: 36231146
DOI: 10.3390/ijerph191911843 -
International Journal of Clinical... 2022Scopus and PubMed databases were systematically searched from their inception to November 2021 to obtain pertinent studies. Standardized mean differences (SMDs) with... (Meta-Analysis)
Meta-Analysis Review
METHODS
Scopus and PubMed databases were systematically searched from their inception to November 2021 to obtain pertinent studies. Standardized mean differences (SMDs) with corresponding 95% confidence intervals (CIs) were calculated to evaluate the difference in Hg levels between people with and without T2DM. The association of the Hg exposure with T2DM was assessed using a random-effects model by pooling the odds ratios (ORs) and 95% CIs.
RESULTS
A total of 17 studies, with 42,917 participants, aged ≥18 years, were analyzed. Overall, Hg levels were significantly higher in T2DM patients compared with non-T2DM controls (SMD = 1.07; 95%CI = 0.59 to 1.55, ≤ 0.001), with significant heterogeneity across studies (I = 96.1%; =≤0.001). No significant association was found between Hg exposure and risk of T2DM in the overall analysis and subgroup analysis based on the source of sample and study design. However, higher exposure to Hg was related to reduced risk of T2DM in men (OR = 0.71; 95%CI = 0.57 to 0.88), but not in women. No significant evidence for publication bias was detected.
CONCLUSIONS
Although the Hg level in T2DM is significantly higher than that of nondiabetics, there was no association between Hg exposure and the overall risk of T2DM. Nevertheless, our study shows that higher exposure to Hg might reduce the risk of T2DM in men.
Topics: Adolescent; Adult; Diabetes Mellitus, Type 2; Female; Humans; Male; Mercury; Odds Ratio
PubMed: 36101810
DOI: 10.1155/2022/7640227 -
Environmental Monitoring and Assessment Aug 2022Mercury (Hg) mobilization and accumulation in the environment is directly related to forest fires. Biomass burning accounts for about 13% of the total contribution of Hg...
Mercury (Hg) mobilization and accumulation in the environment is directly related to forest fires. Biomass burning accounts for about 13% of the total contribution of Hg from natural sources. The aim of this work is to contribute to the knowledge of how wildfires modify mercury compounds behaviour and the effects it has in the Hg cycle, based on a systematic bibliographic review and analysis. Systems dynamics is an adequate focus to analyze the mobilization of Hg due to wildfires, which meets all the requirements to be studied by multimedia modelling. The development and application for the first time of a dynamic multimedia model of Hg taking into account specifically the influences of wildfires is one of the novelties of this work. Different scenarios show that an increase in the number of fires will consequently increase the mercury emitted into the atmosphere, modifying its natural cycle, producing a long-term modification of Hg compositions and concentrations in the different media. Hg movement caused by wildfires can cause complications in living beings and alter the ecosystems. This study found that the Hg soil content could as well be an indicator to measure the impact of fire on the environment. This model can also be generalized to conduct additional studies under comparable conditions, helping to understand the importance of forest fires in global Hg cycles.
Topics: Ecosystem; Environmental Monitoring; Fires; Forests; Mercury; Wildfires
PubMed: 36002668
DOI: 10.1007/s10661-022-10208-3 -
Journal of Biomedical Physics &... Jun 2022Approximately 50% of dental amalgam is elemental mercury by weight. Accumulating body of evidence now shows that not only static magnetic fields (SMF) but both ionizing...
BACKGROUND
Approximately 50% of dental amalgam is elemental mercury by weight. Accumulating body of evidence now shows that not only static magnetic fields (SMF) but both ionizing and non-ionizing electromagnetic radiations can increase the rate of mercury release from dental amalgam fillings. Iranian scientists firstly addressed this issue in 2008 but more than 10 years later, it became viral worldwide.
OBJECTIVE
This review was aimed at evaluating available data on the magnitude of the effects of different physical stressors (excluding chewing and brushing) on the release of toxic mercury from dental amalgam fillings and microleakage.
MATERIAL AND METHODS
The papers reviewed in this study were searched from PubMed, Google Scholar, and Scopus (up to 1 December 2019). The keywords were identified from our initial research matching them with those existing on the database of Medical Subject Headings (MeSH). The non-English papers and other types of articles were not included in this review.
RESULTS
Our review shows that exposure to static magnetic fields (SMF) such as those generated by MRI, electromagnetic fields (EMF) such as those produced by mobile phones; ionizing electromagnetic radiations such as X-rays and non- Ionizing electromagnetic radiation such as lasers and light cure devices can significantly increase the release of mercury from dental amalgam restorations and/or cause microleakage.
CONCLUSION
The results of this review show that a wide variety of physical stressors ranging from non-ionizing electromagnetic fields to ionizing radiations can significantly accelerate the release of mercury from amalgam and cause microleakage.
PubMed: 35698539
DOI: 10.31661/jbpe.v0i0.2009-1175