-
Environmental Science and Pollution... Sep 2022Amounting epidemiological evidence has shown detrimental effects of heavy metals on a wide range of diseases. However, the effect of heavy metal exposure on mortality in... (Meta-Analysis)
Meta-Analysis Review
Association of urinary or blood heavy metals and mortality from all causes, cardiovascular disease, and cancer in the general population: a systematic review and meta-analysis of cohort studies.
Amounting epidemiological evidence has shown detrimental effects of heavy metals on a wide range of diseases. However, the effect of heavy metal exposure on mortality in the general population remains unclear. The primary objective of this study was to clarify the associations between heavy metals and mortality from all causes, cardiovascular disease (CVD), and cancer based on prospective studies. We comprehensively searched Pubmed, Embase, and Web of Science electronic databases to identify studies published from their inception until 1 March 2022. Investigators identified inclusion criteria, extracted study characteristics, and assessed the methodological quality of included studies according to standardized guidelines. Meta-analysis was conducted if the effect estimates of the same outcome were reported in at least three studies. Finally, 42 original studies were identified. The results of meta-analysis showed that cadmium and lead exposure was significantly associated with mortality from all causes, CVD, and cancer in the general population. Moderate evidence suggested there was a link between arsenic exposure and mortality. The adverse effects of mercury and other heavy metals on mortality were inconclusive. Epidemiological evidence for the joint effect of heavy metal exposure on mortality was still indeterminate. In summary, our study provided compelling evidence that exposure to cadmium, lead, and arsenic were associated with mortality from all causes, CVD, and cancer, while the evidence on other heavy metals, for example mercury, was insignificant or indeterminate. Nevertheless, further prospective studies are warranted to explore the joint effects of multiple metal exposure on mortality.
Topics: Arsenic; Cadmium; Cardiovascular Diseases; Cohort Studies; Humans; Lead; Mercury; Metals, Heavy; Neoplasms; Prospective Studies
PubMed: 35917074
DOI: 10.1007/s11356-022-22353-w -
Nutrition Reviews Jan 2022Growing evidence suggests that prenatal exposure to methyl mercury through the maternal diet could have great influence on the neurological and physical development of...
CONTEXT
Growing evidence suggests that prenatal exposure to methyl mercury through the maternal diet could have great influence on the neurological and physical development of neonates and young children.
OBJECTIVE
The aim of this review was to evaluate the clinical repercussions of maternal exposure to methyl mercury during pregnancy on the health of fetuses, neonates, and children up to 8 years of age.
DATA SOURCES
The Web of Science, PubMed, CINAHL, Scopus, and Dialnet Plus databases were searched for articles published in English or Spanish from 1990 to 2020.
STUDY SELECTION
Original articles published in English or Spanish from 1990 to 2020 were eligible for inclusion. All study designs were eligible. Animal studies were excluded. Two authors independently screened studies for inclusion. From the 971 records initially identified, 19 studies were included in the systematic review.
DATA EXTRACTION
PRISMA guidelines were followed. Outcomes extracted included maternal dietary exposure to methyl mercury during pregnancy, possible health repercussions in offspring up to 8 years of age, and quantitative measurement of mercury in a biological sample. All studies met the requirements established for assessing both study quality and risk of bias.
RESULTS
Prenatal exposure to mercury was consistently associated with lower birth weight, but only one study reported a negative association with length at birth. Higher mercury levels were also related to lower scores in various neuropsychological and developmental tests.
CONCLUSION
The literature shows clear evidence of the adverse effects of maternal methyl mercury exposure on anthropometric variables and cognitive or physical development in children. It is noteworthy, however, that mercury toxicity may sometimes be mitigated by other essential nutrients in the maternal diet, such as polyunsaturated fatty acids.
Topics: Animals; Child, Preschool; Diet; Eating; Fatty Acids, Unsaturated; Female; Humans; Infant, Newborn; Maternal Exposure; Mercury; Pregnancy
PubMed: 33954792
DOI: 10.1093/nutrit/nuab029 -
Current Environmental Health Reports Sep 2019Urinary biomonitoring is widely used to assess environmental chemical exposure; however, a critical gap exists in whether and how to correct for the physiological...
BACKGROUND
Urinary biomonitoring is widely used to assess environmental chemical exposure; however, a critical gap exists in whether and how to correct for the physiological variation in water content of spot urine samples.
OBJECTIVE
The aim of this systematic review is to summarize the available evidence comparing the performance of urinary concentration correction methods used to determine urinary levels of arsenic, cadmium, and mercury.
METHODS
We searched PubMed/MEDLINE, Embase, LILIAC, Web of Science, and TOXNET up to Sept. 5, 2017 for articles evaluating urinary concentration correction methods (e.g., urine creatinine [U-Cre], specific gravity [U-SG], osmolality [U-Osm]) compared to 24-h or timed urine specimens for levels of arsenic, cadmium, and mercury. Data on study design, methods of urine collection, and the performance of selected correction methods were extracted.
RESULTS
A total of 10 papers met the inclusion criteria. Two papers evaluated the performance of urinary concentration correction methods for arsenic, four for cadmium, three for mercury, and one for multiple metals. The median sample size for arsenic was 105, for cadmium 107, and for mercury 35. The studies were highly heterogeneous in population selection, urine collection, urine quality control, statistical comparison among selected correction methods, and presentation of the results. The median (range) of correlation coefficients comparing each corrected values with corresponding levels of timed urine specimens are 0.74 (0.17-0.92) for un-correction (n = 13), 0.82 (0.52-0.98) for U-Cre (n = 13), and 0.75 (0.28-0.98) (n = 12) for U-SG.
CONCLUSION
Findings from limited evidence support that urine creatinine and urine-specific gravity corrections remain practical approaches to correct metal concentrations for urine dilution as compared to 24-h or 12-h urine samples. Further studies with larger sample sizes are needed to clarify this fundamental issue of environmental biomonitoring using spot urine samples in both general and priority populations.
Topics: Arsenic; Biomarkers; Cadmium; Environmental Exposure; Environmental Pollutants; Female; Humans; Mercury; Specific Gravity; Urinalysis
PubMed: 31372861
DOI: 10.1007/s40572-019-00242-8 -
Environmental Research Jan 2023Foraminifera are considered good bioindicators of environmental stress based on morphological abnormalities, but physiological responses occur far earlier and have not... (Review)
Review
Foraminifera are considered good bioindicators of environmental stress based on morphological abnormalities, but physiological responses occur far earlier and have not been evaluated as pollution markers. The aim of this review was to collate all published articles reporting physiological changes in foraminifera after environmental and anthropogenic stressors, to evaluate their reliability as early markers of environmental stress. We reviewed 70 studies, meeting the inclusion criteria, reporting 13 physiological effects classes after exposure to 17 different stressors. Immune functions, bleaching and lifecycle disruptions, were the most reported. Amphistegina and Ammonia showed high proportion of effects with lead and mercury, with a significant relationship between these heavy metals and the number of physiological effects classes in Ammonia, and between bleaching in Amphistegina gibbosa and Amphistegina lobifera with solar light and temperature. This suggests physiological responses are potentially reliable early indicators of environmental stress. It is necessary to increase quantitative physiological measures and standard exposure protocols in order to properly evaluate these organisms as pollution bioindicators.
Topics: Foraminifera; Environmental Biomarkers; Ammonia; Reproducibility of Results; Metals, Heavy; Environmental Monitoring; Geologic Sediments; Water Pollutants, Chemical
PubMed: 36270533
DOI: 10.1016/j.envres.2022.114515 -
The Science of the Total Environment Jun 2024Children are at high risk for exposure to toxic metals and are vulnerable to their effects. Significant research has been conducted evaluating the role of these metals... (Review)
Review
BACKGROUND
Children are at high risk for exposure to toxic metals and are vulnerable to their effects. Significant research has been conducted evaluating the role of these metals on immune dysfunction, characterized by biologic and clinical outcomes. However, there are inconsistencies in these studies. The objective of the present review is to critically evaluate the existing literature on the association between toxic metals (lead, mercury, arsenic, and cadmium) and pediatric immune dysfunction.
METHODS
Seven databases (PubMed (NLM), Embase (Elsevier), CINAHL (Ebsco), Web of Science (Clarivate Analytics), ProQuest Public Health Database, and ProQuest Environmental Science Collection) were searched following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in February 2024. Rayaan software identified duplicates and screened by title and abstract in a blinded and independent review process. The remaining full texts were reviewed for content and summarized. Exclusions during the title, abstract, and full-text reviews included: 1) not original research, 2) not epidemiology, 3) did not include toxic metals, 4) did not examine an immune health outcome, or 5) not pediatric (>18 years). This systematic review protocol followed the PRISMA guidelines. Rayaan was used to screen records using title and abstract by two blinded and independent reviewers. This process was repeated for full-text article screening selection.
RESULTS
The search criteria produced 7906 search results; 2456 duplicate articles were removed across search engines. In the final review, 79 studies were included which evaluated the association between toxic metals and outcomes indicative of pediatric immune dysregulation.
CONCLUSIONS
The existing literature suggests an association between toxic metals and pediatric immune dysregulation. Given the imminent threat of infectious diseases demonstrated by the recent COVID-19 epidemic in addition to increases in allergic disease, understanding how ubiquitous exposure to these metals in early life can impact immune response, infection risk, and vaccine response is imperative.
Topics: Humans; Child; Environmental Exposure; Metals, Heavy; Immune System Diseases; Environmental Pollutants; Arsenic; Child, Preschool; Adolescent; Metals
PubMed: 38599398
DOI: 10.1016/j.scitotenv.2024.172303 -
Prostaglandins, Leukotrienes, and... Dec 2019Abundant data are now available to evaluate relationships between seafood consumption in pregnancy and childhood and neurocognitive development. We conducted two...
Abundant data are now available to evaluate relationships between seafood consumption in pregnancy and childhood and neurocognitive development. We conducted two systematic reviews utilizing methodologies detailed by the Dietary Guidelines for Americans Scientific Advisory Committee 2020-2025. After reviewing 44 publications on 106,237 mother-offspring pairs and 25,960 children, our technical expert committee developed two conclusion statements that included the following: "Moderate and consistent evidence indicates that consumption of a wide range of amounts and types of commercially available seafood during pregnancy is associated with improved neurocognitive development of offspring as compared to eating no seafood. Overall, benefits to neurocognitive development began at the lowest amounts of seafood consumed (∼4 oz/wk) and continued through the highest amounts, above 12 oz/wk, some range up to >100 oz/wk.", "This evidence does not meet the criteria for "strong evidence" only due to a paucity of randomized controlled trials that may not be ethical or feasible to conduct for pregnancy" and "Moderate and consistent evidence indicates that consumption of >4 oz/wk and likely >12 oz/wk of seafood during childhood has beneficial associations with neurocognitive outcomes." No net adverse neurocognitive outcomes were reported among offspring at the highest ranges of seafood intakes despite associated increases in mercury exposures. Data are insufficient for conclusive statements regarding lactation, optimal amounts, categories or specific species characterized by mercury content and neurocognitive development; although there is some evidence that dark/oily seafood may be more beneficial. Research was conducted in healthy women and children and is generalizable to US populations. Assessment of seafood as a whole food integrates inherently integrates any adverse effects from neurotoxicants, if any, and benefits to neurocognition from omega-3 fats, as well as other nutrients critical to optimal neurological development. Understanding of the effects of seafood consumption on neurocognition can have significant public health implications.
Topics: Child; Child Development; Fatty Acids, Omega-3; Female; Humans; Mental Health; Mental Processes; Nutrition Assessment; Pregnancy; Prenatal Nutritional Physiological Phenomena; Seafood
PubMed: 31739098
DOI: 10.1016/j.plefa.2019.10.002 -
The Science of the Total Environment Dec 2022Previous studies have indicated that heavy metal levels in milk vary partly depending on environmental metal concentrations. Given the increasing consumption of milk in... (Review)
Review
Previous studies have indicated that heavy metal levels in milk vary partly depending on environmental metal concentrations. Given the increasing consumption of milk in China, it is essential to pay attention to milk safety. We performed a systematic review of relevant published studies to evaluate the heavy metal levels in milk and dairy products and the associated health risks, discuss environmental sources of heavy metals, and propose future research directions. A literature search was implemented in the Web of Science Core Collection and PubMed using multiple keywords such as "metal," "milk," "dairy products," and "China". A total of 16 published studies that analyzed metal levels in milk and dairy products in 20 provincial administrative regions were included. Most studies detected toxic heavy metals in milk and dairy products samples, including mercury, lead, cadmium, chromium, and arsenic. The lead concentration in milk from these studies did not exceed the Chinese standard for milk. However, three studies detected relatively high lead levels in both commercial and raw milk, exceeding the European Commission standard. The polluted environment surrounding the farm, feed, and packaging materials are likely sources of metals in milk and dairy products. The hazard index for the 11 analyzed metal elements in milk and dairy products was lower than 1, indicating negligible non-carcinogenic health risks from exposure to these metals. Children are at a higher risk than adults. This review illustrates that research in this field is limited to China. More research should be conducted in the future, such as evaluating the contribution of each environmental source of metal in milk and dairy products.
Topics: Adult; Animals; Arsenic; Cadmium; Child; Chromium; Environmental Monitoring; Humans; Lead; Mercury; Metals, Heavy; Milk; Risk Assessment
PubMed: 35988597
DOI: 10.1016/j.scitotenv.2022.158161 -
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 -
Journal of Hazardous Materials Feb 2022Coastal wetlands are ecosystems lying between land and ocean and are subject to inputs of heavy metals (HMs) from terrestrial, oceanic and atmospheric sources. Although... (Review)
Review
Coastal wetlands are ecosystems lying between land and ocean and are subject to inputs of heavy metals (HMs) from terrestrial, oceanic and atmospheric sources. Although the study on HM pollution in coastal wetlands has been rapidly developing over the past three decades, systematic reviews are still unavailable. Here, by analyzing 3343 articles published between 1990 and 2019, we provided the first holistic systematic review of studies on HM pollution in coastal wetlands globally. The results showed a trend of rapid increases in publications in this field globally, especially over the past ten years. Trends varied greatly among coastal countries, and global trends were primarily driven by the US before 2000, and in China after 2010. We also found that mercury (Hg), cadmium (Cd), and copper (Cu) were the most widely studied HM elements globally, but patterns differed geographically, with Hg being most widely examined in the Americas, Cd in China and India, and lead (Pb) in the western Europe and Australia, respectively. Among different types of coastal wetlands, salt marshes, mangrove forests, and estuaries were the most widely studied, in contrast to seagrass beds and tidal flats. As for ecosystem components, soils/sediments and plants were most extensively investigated, while algae, microbes, and animals were much less examined. Our analysis further revealed rapid emergence of topics on anthropogenic sources, interactions with other anthropogenic environmental changes (climate change in particular), and control and remediation methodology in the literature in the recent ten years. Moving forward, we highlight that future studies are needed to i) better understand the impacts of HM pollution in less studied coastal wetland systems and species, ii) deepen current understanding of the biogeochemical behaviors of HMs under anthropogenic activities, iii) examine interactions with other anthropogenic environmental changes, iv) conceive ecological remediation (i.e., "ecoremediation" as compared to traditional physiochemical remediation and bioremediation) strategies, and v) develop advanced analysis instruments and methods. The perspectives we brought forward can help stimulate many new advances in this field.
Topics: Anthropogenic Effects; China; Ecosystem; Environmental Monitoring; Environmental Pollution; Geologic Sediments; Metals, Heavy; Wetlands
PubMed: 34600393
DOI: 10.1016/j.jhazmat.2021.127312 -
Cureus Jan 2024Tranexamic acid (TXA), a fibrinolytic agent, effectively inhibits plasminogen activation, thereby reducing fibrinolysis and hemorrhage. This study focused on its... (Review)
Review
Tranexamic acid (TXA), a fibrinolytic agent, effectively inhibits plasminogen activation, thereby reducing fibrinolysis and hemorrhage. This study focused on its application in trauma patients undergoing emergency surgery, a critical area due to trauma's significant role in mortality. Our investigation involved a meticulous screening of randomized controlled trials from databases including Scopus, PubMed, Web of Science, and Cochrane. The findings indicate that TXA intervention is promising in enhancing outcomes for trauma patients. However, the drug's effectiveness may vary based on the specific nature of the medical condition. In summary, robust evidence suggests that TXA can diminish blood loss, lower transfusion rates, reduce complications, and improve hemoglobin and hematocrit levels in surgical patients. Consequently, TXA should be considered a crucial medication, readily available to mitigate morbidity and mortality in surgical settings. Future research should explore factors influencing TXA's effectiveness in traumatic brain injury cases and across a broad spectrum of surgical scenarios in diverse patient populations. This would further guide clinicians in refining and optimizing the use of TXA.
PubMed: 38213943
DOI: 10.7759/cureus.52111