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Environmental Research Jul 2024Polychlorinated biphenyls (PCBs), extensively used in various products, prompt ongoing concern despite reduced exposure since the 1970s. This systematic review explores... (Review)
Review
BACKGROUND
Polychlorinated biphenyls (PCBs), extensively used in various products, prompt ongoing concern despite reduced exposure since the 1970s. This systematic review explores prenatal PCB and hydroxylated metabolites (OH-PCBs) exposure's association with child neurodevelopment. Encompassing cognitive, motor development, behavior, attention, ADHD, and ASD risks, it also evaluates diverse methodological approaches in studies.
METHODS
PubMed, Embase, PsycINFO, and Web of Science databases were searched through August 23, 2023, by predefined search strings. Peer-reviewed studies published in English were included. The inclusion criteria were: (i) PCBs/OH-PCBs measured directly in maternal and cord blood, placenta or breast milk collected in the perinatal period; (ii) outcomes of cognitive development, motor development, attention, behavior, attention-deficit/hyperactivity disorder (ADHD), and autism spectrum disorder (ASD) among children≤18 years old. Quality assessment followed the National Heart, Lung, and Blood Institute's tool.
RESULTS
Overall, 87 studies were included in this review. We found evidence for the association between perinatal PCB exposure and adverse cognitive development and attention issues in middle childhood. There appeared to be no or negligible link between perinatal PCB exposure and early childhood motor development or the risk of ADHD/ASD. There was an indication of a sex-specific association with worse cognition and attention scores among boys. Some individual studies suggested a possible association between prenatal exposure to OH-PCBs and neurodevelopmental outcomes. There was significant heterogeneity between the studies in exposure markers, exposure assessment timing, outcome assessment, and statistical analysis.
CONCLUSIONS
Significant methodological, clinical and statistical heterogeneity existed in the included studies. Adverse effects on cognitive development and attention were observed in middle childhood. Little or no apparent link on both motor development and risk of ADHD/ASD was observed in early childhood. Inconclusive evidence prevailed regarding other neurodevelopmental aspects due to limited studies. Future research could further explore sex-specific associations and evaluate associations at lower exposure levels post-PCB ban in the US. It should also consider OH-PCB metabolites, co-pollutants, mixtures, and their potential interactions.
Topics: Humans; Polychlorinated Biphenyls; Female; Pregnancy; Environmental Pollutants; Prenatal Exposure Delayed Effects; Child; Child Development; Child, Preschool; Attention Deficit Disorder with Hyperactivity; Neurodevelopmental Disorders; Maternal Exposure; Male; Cognition; Infant
PubMed: 38615789
DOI: 10.1016/j.envres.2024.118912 -
The Science of the Total Environment Nov 2021Reduced water quality degrades coral reefs, resulting in compromised ecosystem function and services to coastal communities. Increasing management capacity on reefs... (Meta-Analysis)
Meta-Analysis Review
Reduced water quality degrades coral reefs, resulting in compromised ecosystem function and services to coastal communities. Increasing management capacity on reefs requires prioritization of the development of data-based water-quality thresholds and tipping points. To meet this urgent need of marine resource managers, we conducted a systematic review and meta-analysis that quantified the effects on scleractinian corals of chemical pollutants from land-based and atmospheric sources. We compiled a global dataset addressing the effects of these pollutants on coral growth, mortality, reproduction, physiology, and behavior. The resulting quantitative review of 55 articles includes information about industrial sources, modes of action, experimentally tested concentrations, and previously identified tolerance thresholds of corals to 13 metals, 18 pesticides, 5 polycyclic aromatic hydrocarbons (PAHs), a polychlorinated biphenyl (PCB), and a pharmaceutical. For data-rich contaminants, we make more robust threshold estimates by adapting models for Bayesian hierarchical meta-analysis that were originally developed for biopharmaceutical application. These models use information from multiple studies to characterize the dose-response relationships (i.e., E curves) between a pollutant's concentration and various measures of coral health. Metals used in antifouling paints, especially copper, have received a great deal of attention to-date, thus enabling us to estimate the cumulative impact of copper across coral's early life-history. The effects of other land-based pollutants on corals are comparatively understudied, which precludes more quantitative analysis. We discuss opportunities to improve future research so that it can be better integrated into quantitative assessments of the effects of more pollutant types on sublethal coral stress-responses. We also recommend that managers use this information to establish more conservative water quality thresholds that account for the synergistic effects of multiple pollutants on coral reefs. Ultimately, active remediation of local stressors will improve the resistance, resilience, and recovery of individual reefs and reef ecosystems facing the global threat of climate change.
Topics: Animals; Anthozoa; Bayes Theorem; Coral Reefs; Ecosystem; Water Quality
PubMed: 34323749
DOI: 10.1016/j.scitotenv.2021.148632 -
Environmental Research Jul 2023The effects of environmental pollution are associated with higher rates of mortality, morbidity, and years of life lost. It is known that these produce alterations in... (Meta-Analysis)
Meta-Analysis Review
The effects of environmental pollution are associated with higher rates of mortality, morbidity, and years of life lost. It is known that these produce alterations in the human body, including changes in body composition. Research has focused on the association between contaminants and BMI through cross-sectional studies. The objective of this study was to synthesize the evidence for the association of pollutants on different measures of body composition. The PECOS strategy was defined, in which "P": participants of any age, sex, or ethnicity, "E": a higher level of environmental pollution, "C": a lower level of environmental pollution, "O": body composition measurements and "S": longitudinal studies. Studies from the following databases were included: MEDLINE, EMBASE, SciELO, LILACS, Scopus, Web of Science, SPORTDiscus, and gray literature from inception to January 2023.3069 studies were identified, 18 were included in the systematic review, and 13 in the meta-analysis. These studies included 8.563 people, 47 environmental contaminants, and 16 measures of body composition. The meta-analysis by subgroup found that the association between dioxins, furans, PCBs, and waist circumference was β = 1.0 (95% CI: 0.85 to 1.16; I: 95%), and the sum of four skinfolds β = 1.02 (95% CI: 0.88 to 1.16; I: 24%). The association between pesticides and waist circumference was β = 1.00 (95% CI: 0.68 to 1.32; I: 98%), and the fat mass was β = 0.99 (95% CI: 0.17 to 1.81; I: 94%). Pollutants, especially endocrine-disrupting chemicals, among which dioxins, furans, PCBs, and pesticides, are associated with changes in body composition, mainly with waist circumference and the sum of four skinfolds.
Topics: Humans; Environmental Pollutants; Polychlorinated Biphenyls; Dioxins; Cross-Sectional Studies; Body Composition; Pesticides
PubMed: 37024033
DOI: 10.1016/j.envres.2023.115840 -
Environmental Monitoring and Assessment May 2024Dioxins and dioxin-like polychlorinated biphenyls are a group of lipophilic compounds classified under persistent environmental pollutants (POPs). Significant sources of... (Review)
Review
Dioxins and dioxin-like polychlorinated biphenyls are a group of lipophilic compounds classified under persistent environmental pollutants (POPs). Significant sources of dioxin emissions include industrial effluents, open burning practices, and biomedical and municipal waste incinerators. These emissions will enter the food chain and accumulate in animal-origin foods (AOFs). A systematic review was conducted to analyze the global levels of dioxins and dioxin-like PCBs in AOFs using PRISMA guidelines 2020. The data on the dioxin contamination in AOFs were extracted from 53 publications based on their presence in eggs, meat and meat products, milk and dairy products, marine fish and fish products, and freshwater fish and crabs. A gap analysis was conducted based on the systematic review to understand the grey areas to be focused on the future. No trend of dioxin contamination in AOFs was observed. A significant gap area was found in the need for nationwide data generation in countries without periodic monitoring of AOFs for dioxin contamination. Source apportionment studies need to be explored for the dioxin contamination of AOFs. Large-scale screening tests of AOFs using DR-CALUX based on market surveys are required for data generation. The outcomes of the study will be helpful for stakeholders and policyholders in framing new policies and guidelines for food safety in AOFs.
Topics: Dioxins; Polychlorinated Biphenyls; Animals; Food Contamination; Environmental Monitoring; Meat; Environmental Pollutants; Persistent Organic Pollutants
PubMed: 38724861
DOI: 10.1007/s10661-024-12690-3 -
Environmental Research Jul 2020Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) are relevant families of persistent organic pollutants, which have been linked to several long-term...
BACKGROUND
Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) are relevant families of persistent organic pollutants, which have been linked to several long-term adverse health effects. The mechanisms of action of these pollutants are still poorly understood. However, there are some evidences suggesting that inflammation might play a key role on their effects.
AIM
To systematically synthesize the published in vitro, in vivo and epidemiological data assessing the potential influence of exposure to OCPs and PCBs on the development of an inflammatory milieu.
METHODS
A systematic review of peer-reviewed original research papers published until 1st May 2019 was conducted, by using Medline, Web of Science and Scopus databases. A total of 39 articles met the inclusion criteria and were evaluated in this review.
RESULTS
The majority of the studies showed significant associations of PCB and OCP exposure with all inflammatory markers measured (n = 30). Some studies showed positive and negative associations (n = 7) and only two studies evidenced negative associations (n = 2). Most of the available evidences came from in vitro and in vivo studies (n = 31), with few epidemiological studies (n = 8).
CONCLUSIONS
We found consistent positive associations between exposure to PCBs and OCPs and the development of a pro-inflammatory milieu, with only few discrepancies. However, given the limited epidemiological evidence found, our results warrant further research in order to elucidate the real contribution of these pollutants on the inflammatory processes and subsequent diseases.
Topics: Environmental Monitoring; Environmental Pollutants; Epidemiologic Studies; Humans; Hydrocarbons, Chlorinated; Pesticides; Polychlorinated Biphenyls
PubMed: 32668538
DOI: 10.1016/j.envres.2020.109561 -
Ecotoxicology and Environmental Safety Feb 2023Based on a systematic review and meta-analysis of articles published in PubMed, Embase, Cochrane, and Web of Science, we identified nine articles that provide evidence... (Meta-Analysis)
Meta-Analysis Review
Based on a systematic review and meta-analysis of articles published in PubMed, Embase, Cochrane, and Web of Science, we identified nine articles that provide evidence of the relationship between persistent organic pollutants and hyperuricemia. Our researchers assess the quality of the included studies and their risk of bias using the recommended method and tool. This study uses meta-analyses of the random effects of each exposure and outcome to estimate combined odds ratios (ORs) and 95% confidence intervals (CIs). We found that the risk of hyperuricemia was strongly associated with three perfluorinated compounds, PFNA, PFOA, and PFOS, with the OR(95%CI) of 1.26 (1.07-1.47), 1.44(1.15-1.79), and 1.23(1.01-1.50) respectively. We also found a weak association between two other perfluorinated compounds, PFDA and PFHxS. Other than that, the summary ORs (95% CIs) of incident hyperuricemia were 2.34 (1.79-3.08) for DDT, 3.25(2.40-4.39) for DDE, 2.57 (1.37-4.81) for PCBs and 3.05(2.22-4.19) in trans-nonanchlor. Therefore, DDT and its breakdown product, DDE, PCBs, and trans-nonanchlor have also been linked with an increased risk of hyperuricemia in humans. This study finds that persistent organic pollutant is a critical factor for hyperuricemia, and further studies in specific regions will be considered in the future.
Topics: Humans; Hyperuricemia; Persistent Organic Pollutants; Polychlorinated Biphenyls; DDT
PubMed: 36640578
DOI: 10.1016/j.ecoenv.2023.114525 -
Biochemical Pharmacology Jul 2024Epidemiological evidence links chemical exposure with type 2 diabetes (T2DM) risk and prevalence. Chemical exposure may therefore also limit success of weight loss or... (Meta-Analysis)
Meta-Analysis Review
A systematic review and meta-analysis of environmental contaminant exposure impacts on weight loss and glucose regulation during calorie-restricted diets in preclinical studies: Persistent organic pollutants may impede glycemic control.
Epidemiological evidence links chemical exposure with type 2 diabetes (T2DM) risk and prevalence. Chemical exposure may therefore also limit success of weight loss or restoration of glycemic control during calorie restricted diets. Few human studies examine this hypothesis. This systematic review and clustered meta-analysis examines preclinical evidence that exposure to anthropogenic environmental contaminants impedes weight loss and resumption of glycemic control during calorie restriction. Of five eligible papers from 212 unique citations, four used C57BL/6 mice and one used Sprague Dawley rats. In four the animals received high fat diets to induce obesity and impaired glycemic control. All examined persistent organic pollutants (POPs). Polychlorinated biphenyl (PCB) 77 exposure did not affect final mass (standardised mean difference (SMD) = -0.35 [-1.09, 0.39]; n = 5 (experiments); n = 3 (papers)), or response to insulin in insulin tolerance tests (SMD = -1.54 [-3.25, 0.16] n = 3 (experiments); n = 2 (papers)), but impaired glucose control in glucose tolerance tests (SMD = -1.30 [-1.96, -0.63]; n = 6 (experiments); n = 3 (papers)). The impaired glycemic control following perfluoro-octane sulphonic acid (PFOS) exposure and enhanced mass loss following dichlorodiphenyltrichloroethane (DDT) exposure have not been replicated. Animal studies thus suggest some chemical groups, especially PCB and PFOS, could impair glucose control management during calorie restriction, similar to conclusions from limited existing clinical studies. We discuss the research that is urgently required to inform weight management services that are now the mainstay prevention initiative for T2DM.
Topics: Animals; Mice; Blood Glucose; Caloric Restriction; Diabetes Mellitus, Type 2; Environmental Exposure; Environmental Pollutants; Glycemic Control; Persistent Organic Pollutants; Weight Loss; Disease Models, Animal; Rats
PubMed: 38782075
DOI: 10.1016/j.bcp.2024.116300 -
Journal of Environmental Management Dec 2021Despite the increasing use of chemical additives in construction and their potential threat to the environment and human health, many C&DW studies lack a comprehensive... (Review)
Review
Despite the increasing use of chemical additives in construction and their potential threat to the environment and human health, many C&DW studies lack a comprehensive view of chemicals of concern (COC) in C&DW. This study systematically reviewed published studies from 2010 to August 2021 using a keyword search methodology to explore COC in C&DW fine residues based on 73 articles identified from 5 prominent databases. Results show that trace/heavy metals (As, Cr, Cu, Cd, and Pb) as well as high concentrations of toxic gasses (methane, hydrogen sulphide and mercury vapour) have been reported in landfills. Besides, organic chemicals such as polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and brominated flame retardants have been found in landfill leachates in the Netherlands and widely detected in landfill leachates in Sweden, Japan, and Canada. The potential of these contaminants to cause health complications has also been reported. Carcinogenicity, liver and kidney damage, cumulative damage, neurological disorders and foetal damage were reported as associated health implications of exposure to COC from C&DW. A waste disposal lens was used to explore the factors that influence the environment and human health impacts (pH, gypsum and organic content, size fraction, atmospheric exposure and liquid infiltration rate). Despite environmental and health issues relating to C&DW fine residues, the ultimate destination for C&DW fine residues remains in general landfills. Although significant efforts in managing C&DW have been implemented at various levels, those specifically targeting C&DW fine residues remain sparse.
Topics: Environmental Monitoring; Flame Retardants; Humans; Refuse Disposal; Waste Disposal Facilities; Water Pollutants, Chemical
PubMed: 34482107
DOI: 10.1016/j.jenvman.2021.113654 -
European Journal of Cancer Prevention :... Sep 2019We carryied out a meta-analysis of studies on exposure to polychlorinated biphenyls (PCBs) and risk of non-Hodgkin lymphoma (NHL). Through a systematic search of the... (Meta-Analysis)
Meta-Analysis
We carryied out a meta-analysis of studies on exposure to polychlorinated biphenyls (PCBs) and risk of non-Hodgkin lymphoma (NHL). Through a systematic search of the literature, we identified relative risks (RRs) for PCB exposure and NHL risk in 30 populations (10 occupational exposure, seven high environmental exposure, 13 without special exposure). We performed random effects meta-analyses for exposure to all PCBs, specific PCB congeners and risk of all NHL and NHL subtypes. The meta-RR for studies of occupational exposure, high environmental exposure, and no special exposure were 0.94 [95% confidence interval (CI): 0.84-1.03], 1.05 (95% CI: 0.94-1.16), and 1.03 (95% CI: 0.72-1.34), respectively, and the cumulative meta-RR was 0.96 (95% CI: 0.85-1.07). No positive associations were found for exposure to specific congeners, nor for NHL subtypes. The meta-RR for an increase of 100 ppb serum or fat PCB level was 1.02 (95% CI: 1.00-1.04). There was weak indication of publication bias. Our meta-analysis found no association between PCB exposure and NHL risk, in particular in studies of occupational exposures. We detected a weak dose-response relation; the possibility of residual confounding and other sources of bias cannot be ruled out. PCBs are not likely to cause NHL in humans.
Topics: Environmental Exposure; Humans; Lymphoma, Non-Hodgkin; Occupational Exposure; Polychlorinated Biphenyls; Risk Factors
PubMed: 30234686
DOI: 10.1097/CEJ.0000000000000463 -
Environmental Research Sep 2020Environmental risks are responsible for one in five of all deaths worldwide. Persistent, bioaccumulative, and toxic substances are chemicals that can subsist for decades...
Environmental risks are responsible for one in five of all deaths worldwide. Persistent, bioaccumulative, and toxic substances are chemicals that can subsist for decades in human tissues and the environment. They include heavy metals, organochlorines, polychlorinated biphenyls, organobromines, organofluorines, and polycyclic aromatic hydrocarbons among others. Although humans are often exposed to multiple pollutants simultaneously, their negative effects on health have generally been studied for each one separately. Among the most severe of these harmful effects is cancer. Here, to compile and analyze the available evidence on the relationship between exposure to mixtures of persistent, bioaccumulative, and toxic chemicals and the risk of developing cancer in the general population, we provide a systematic review based on the main databases (Cochrane, PubMed and Embase), together with complementary sources, using the general methodology of the PRISMA Statement. The articles analyzed were selected by two researchers working independently and their quality was evaluated by reference to the Newcastle-Ottawa scale. The initial search yielded 2379 results from the main sources of information and 22 from the complementary ones. After the article selection process, 22 were included in the final review (21 case-control studies and one cohort study). Analysis of the selected studies revealed that most of the mixtures analyzed were positively associated with risk of cancer, especially that of the breast, colon-rectum or testis, and more strongly so than each contaminant alone. In view of the possible stronger association observed with the development of cancer for some mixtures of pollutants than when each one is present separately, exposure to mixtures should also be monitored and measured, preferably in cohort designs, to complement the traditional approach to persistent, bioaccumulative, and toxic chemicals. The results presented should be taken into account in public health policies in order to strengthen the regulatory framework for cancer prevention and control.
Topics: Case-Control Studies; Cohort Studies; Environmental Pollutants; Humans; Male; Neoplasms; Polychlorinated Biphenyls
PubMed: 32798941
DOI: 10.1016/j.envres.2020.109787