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Current Environmental Health Reports Dec 2023We performed a systematic review and meta-analysis on the relation between fluoride exposure and skeletal fluorosis (SF) using a novel statistical methodology for... (Meta-Analysis)
Meta-Analysis Review
PURPOSE OF REVIEW
We performed a systematic review and meta-analysis on the relation between fluoride exposure and skeletal fluorosis (SF) using a novel statistical methodology for dose-response modeling.
RECENT FINDINGS
Skeletal fluorosis, a major health issue that is endemic in some regions, affects millions of people worldwide. However, data regarding the dose-response relation between fluoride exposure and SF are limited and outdated. We included twenty-three studies in the meta-analysis. When comparing the highest versus the lowest fluoride category, the summary risk ratio (RR) for SF prevalence was 2.05 (95% CI 1.60; 2.64), with a value of 2.73 (95% CI 1.92; 3.90) for drinking water and 1.40 (95% CI 0.90; 2.17) for urinary fluoride. The RR by the risk of bias (RoB) was 2.37 (95% CI 1.56; 3.58) and 1.78 (95% CI 1.34; 2.36) for moderate and high RoB studies, respectively. The dose-response curve based on a one-stage cubic spline regression model showed an almost linear positive relation between exposure and SF occurrence starting from relatively low concentrations up to 5 mg/L and 2.5 mg/L, respectively, for water and urinary fluoride, with no substantial increase above this threshold. The RR for developing moderate-severe forms increases at 5.00 mg/L and 2.5 mg/L of water and urinary fluoride, respectively. Better-quality studies are needed to confirm these results, but greater attention should be given to water fluoride levels to prevent SF, in addition to the other potential adverse effects of fluoride exposure.
Topics: Humans; Fluorides; Fluorosis, Dental; Drinking Water; Prevalence
PubMed: 37861949
DOI: 10.1007/s40572-023-00412-9 -
BMC Medicine Feb 2024Environmental factors play an important role in developing mental disorders. This study aimed to investigate the associations of metal and nonmetal elements in drinking...
BACKGROUND
Environmental factors play an important role in developing mental disorders. This study aimed to investigate the associations of metal and nonmetal elements in drinking water with the risk of depression and anxiety and to assess whether diets modulate these associations.
METHODS
We conducted a prospective cohort study including 24,285 participants free from depression and anxiety from the Yinzhou Cohort study in the 2016-2021 period. The exposures were measured by multiplying metal and nonmetal element concentrations in local pipeline terminal tap water samples and total daily drinking water intakes. Cox regression models adjusted for multi-level covariates were used to estimate adjusted hazard ratios (aHRs) and 95% confidence intervals (95%CIs).
RESULTS
During an average follow-up period of 4.72 and 4.68 years, 773 and 1334 cases of depression and anxiety were identified, respectively. A 1 standard deviation (SD) increase in manganese exposure reduced the incidence of depression by 8% (HR 0.92, 95%CI 0.88 to 0.97). In contrast, with a 1 SD increase in copper and cadmium exposure, the incidence of depression increased by 6% (HR 1.06, 95%CI 1.01 to 1.11) and 8% (HR 1.08, 95%CI 1.00 to 1.17), respectively. The incidence of anxiety increased by 39% (HR 1.39, 95%CI 1.20 to 1.62), 33% (HR 1.33, 95%CI 1.03 to 1.71), and 14% (HR 1.14, 95%CI 1.03 to 1.25) respectively for a 1 SD increase in manganese, iron, and selenium exposure. Diets have a moderating effect on the associations of metal and nonmetal elements with the risk of anxiety. Stronger associations were observed in older, low-income groups and low-education groups.
CONCLUSIONS
We found significant associations between exposure to metal and nonmetal elements and depression and anxiety. Diets regulated the associations to some extent.
Topics: Humans; Aged; Cohort Studies; Drinking Water; Manganese; Prospective Studies; Mental Health; Diet
PubMed: 38302940
DOI: 10.1186/s12916-024-03269-3 -
Chemosphere Aug 2023The risk of eukaryotic microorganisms in drinking water treatment has not received sufficient attention. As the final step in ensuring drinking water quality, the... (Meta-Analysis)
Meta-Analysis Review
The risk of eukaryotic microorganisms in drinking water treatment has not received sufficient attention. As the final step in ensuring drinking water quality, the effectiveness of disinfection in inactivating eukaryotic microorganisms remains to be qualitatively and quantitatively demonstrated. In this study, we conducted a meta-analysis using a mixed effects model and bootstrapping analysis to assess the effects of the disinfection process on eukaryotic microorganisms. The results revealed significant reduction of eukaryotic microorganisms in drinking water associated with the disinfection process. The estimated logarithmic reduction rates for chlorination, ozone, and UV disinfection were 1.74, 1.82 and 2.15 log, respectively, for all eukaryotic microorganisms. Analysis of relative abundance variation of eukaryotic microorganisms also indicated certain phyla and classes exhibited tolerance and competitive advantage during disinfection. This study provides qualitatively and quantitatively analysis on the influence of drinking water disinfection processes on eukaryotic microorganisms, and highlights the persistent risk of eukaryotic microbial contamination in drinking water even after disinfection, calling for further optimization of current conventional disinfection methods.
Topics: Disinfection; Drinking Water; Eukaryota; Water Purification; Water Quality
PubMed: 37142108
DOI: 10.1016/j.chemosphere.2023.138839 -
Toxins Dec 2023A seasonal plethora of cyanobacteria in the plankton community can have severe implications, not only for water ecosystems but also for the availability of treated...
A seasonal plethora of cyanobacteria in the plankton community can have severe implications, not only for water ecosystems but also for the availability of treated water. The catchment of the Obrzyca River (a source of drinking water) is seasonally exposed to harmful cyanobacterial bloom. Previous studies (2008-2012; 2019) revealed that the most polluted water of the Obrzyca River was Uście, close to the outlet of Rudno Lake (at the sampling point). Therefore, the effect on this lake was specifically examined in this study. Sampling was performed from May to September at that site and from July to September 2020 at Rudno Lake. The conducted analysis revealed a massive growth of , especially in Rudno Lake. The results showed not only the distinct impact of cyanobacterial bloom on phytoplankton biodiversity but also the presence of microcystins and other cyanopeptides in both sampling points. The maximal total concentration of microcystins (dmMC-RR, MC-RR, dmMC-LR, MC-LR, MC-LY, MC-YR) equaled 57.3 μg/L and the presence of cyanopeptides (aeruginosin, anabaenopeptin) was originally determined in Rudno Lake, August 2021. The presence of these toxins was highlighted in our results for the first time. The same samples from the lake were the most toxic in biotoxicological investigations using the planarian The performed bioassays proved that is a sensitive bioindicator for cyanotoxins. The physical and chemical indicators of water quality, i.e., color, temperature, total suspended solids, and total nitrogen and phosphorus, showed a significant correlation among each other and towards cyanobacterial abundance and microcystin concentrations.
Topics: Water Quality; Microcystins; Drinking Water; Ecosystem; Cyanobacteria; Lakes
PubMed: 38133207
DOI: 10.3390/toxins15120703 -
International Journal of Environmental... Apr 2024Lead is an established neurotoxicant, and it has known associations with adverse neurodevelopmental and reproductive outcomes. Exposure to lead at any level is unsafe,...
Lead is an established neurotoxicant, and it has known associations with adverse neurodevelopmental and reproductive outcomes. Exposure to lead at any level is unsafe, and the United States (US) has enacted various federal and state legislations to regulate lead levels in drinking water in K-12 schools and childcare facilities; however, no regulations exist for higher education settings. Upon the discovery of lead in drinking water fixtures in the University of North Carolina at Chapel Hill (UNC-CH) campus, a cross-campus water testing network and sampling plan was developed and deployed. The campaign was based on the US Environmental Protection Agency's (EPA) 3Ts (Training, Testing, and Taking Action) guidance. The seven-month campaign involved 5954 tests on 3825 drinking water fixtures across 265 buildings. A total of 502 (8.43%) tests showed lead above the limit of detection (1 part per billion, ppb), which represented 422 (11.03%) fixtures. Fewer than 1.5% of the tests were above the EPA action level for public water systems (15 ppb). In conclusion, systematic testing of all the fixtures across campus was required to identify localized contamination, and each entity in the cross-campus network undertook necessary roles to generate a successful testing campaign. UNC-CH established preventative measures to test drinking water fixtures every three years, which provide a framework for other higher education institutions in responding to lead contamination.
Topics: Lead; Drinking Water; Universities; North Carolina; Water Pollutants, Chemical; Humans; Environmental Monitoring; United States; United States Environmental Protection Agency
PubMed: 38791777
DOI: 10.3390/ijerph21050561 -
Journal of Water and Health May 2024
Topics: Drinking Water; Humans; Water Supply; Water Quality
PubMed: 38822459
DOI: 10.2166/wh.2024.002 -
The Science of the Total Environment Dec 2023This review paper examines the drinking water quality issues in remote and Indigenous communities, with a specific emphasis on Australia. Access to clean and safe... (Review)
Review
This review paper examines the drinking water quality issues in remote and Indigenous communities, with a specific emphasis on Australia. Access to clean and safe drinking water is vital for the well-being of Indigenous communities worldwide, yet numerous challenges hinder their ability to obtain and maintain water security. This review focuses on the drinking water-related issues faced by Indigenous populations in countries such as the United States, Canada, New Zealand, and Australia. In the Australian context, remote and Indigenous communities encounter complex challenges related to water quality, including microbial and chemical contamination, exacerbated by climate change effects. Analysis of water quality trends in Queensland, New South Wales, Western Australia, and the Northern Territory reveals concerns regarding various pollutants with very high concentrations in the source water leading to levels exceeding recommended drinking water limits such as hardness, turbidity, fluoride, iron, and manganese levels after limited treatment facilities available in these communities. Inadequate water quality and quantity contribute to adverse health effects, particularly among Indigenous populations who may resort to sugary beverages. Addressing these challenges requires comprehensive approaches encompassing testing, funding, governance, appropriate and sustainable treatment technologies, and cultural considerations. Collaborative efforts, risk-based approaches, and improved infrastructure are essential to ensure equitable access to clean and safe drinking water for remote and Indigenous communities, ultimately improving health outcomes and promoting social equity.
Topics: United States; Australia; Water Quality; Drinking Water; New South Wales; Queensland
PubMed: 37633366
DOI: 10.1016/j.scitotenv.2023.166559 -
Environmental Science & Technology Dec 2023We investigated the metabolomic profile associated with exposure to trihalomethanes (THMs) and nitrate in drinking water and with colorectal cancer risk in 296 cases and...
We investigated the metabolomic profile associated with exposure to trihalomethanes (THMs) and nitrate in drinking water and with colorectal cancer risk in 296 cases and 295 controls from the Multi Case-Control Spain project. Untargeted metabolomic analysis was conducted in blood samples using ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. A variety of univariate and multivariate association analyses were conducted after data quality control, normalization, and imputation. Linear regression and partial least-squares analyses were conducted for chloroform, brominated THMs, total THMs, and nitrate among controls and for case-control status, together with a N-integration model discriminating colorectal cancer cases from controls through interrogation of correlations between the exposure variables and the metabolomic features. Results revealed a total of 568 metabolomic features associated with at least one water contaminant or colorectal cancer. Annotated metabolites and pathway analysis suggest a number of pathways as potentially involved in the link between exposure to these water contaminants and colorectal cancer, including nicotinamide, cytochrome P-450, and tyrosine metabolism. These findings provide insights into the underlying biological mechanisms and potential biomarkers associated with water contaminant exposure and colorectal cancer risk. Further research in this area is needed to better understand the causal relationship and the public health implications.
Topics: Humans; Drinking Water; Trihalomethanes; Nitrates; Spain; Colorectal Neoplasms; Water Pollutants, Chemical
PubMed: 37962559
DOI: 10.1021/acs.est.3c05814 -
Integrating different tools and technologies to advance drinking water quality exposure assessments.Journal of Exposure Science &... Jan 2024Contaminants in drinking water are a major contributor to the human exposome and adverse health effects. Assessing drinking water exposure accurately in health studies... (Review)
Review
Contaminants in drinking water are a major contributor to the human exposome and adverse health effects. Assessing drinking water exposure accurately in health studies is challenging, as several of the following study design domains should be addressed as adequately as possible. In this paper, we identify the domains Time, Space, Data Quality, Data Accessibility, economic considerations of Study Size, and Complex Mixtures. We present case studies for three approaches or technologies that address these domains differently in the context of exposure assessment of drinking water quality: regulated contaminants in monitoring databases, high-resolution mass spectrometry (HRMS)-based wide-scope chemical analysis, and effect-based bioassay methods. While none of these approaches address all the domains sufficiently, together they have the potential to carry out exposure assessments that would complement each other and could advance the state-of-science towards more accurate risk analysis. The aim of our study is to give researchers investigating health effects of drinking water quality the impetus to consider how their exposure assessments relate to the above-mentioned domains and whether it would be worthwhile to integrate the advanced technologies presented into planned risk analyses. We highly suggest this three-pronged approach should be further evaluated in health risk analyses, especially epidemiological studies concerning contaminants in drinking water. The state of the knowledge regarding potential benefits of these technologies, especially when applied in tandem, provides more than sufficient evidence to support future research to determine the implications of combining the approaches described in our case studies in terms of protection of public health.
Topics: Humans; Drinking Water; Gas Chromatography-Mass Spectrometry; Biological Assay; Databases, Factual; Exposome
PubMed: 37553410
DOI: 10.1038/s41370-023-00588-0 -
Environmental Science and Pollution... Jul 2023This study reports the occurrence and risk assessment of 2,4-dinitrophenol (2,4-DNP), phenol (PHE), and 2,4,6-trichlorophenol (2,4,6-TCP) in drinking water sources in...
This study reports the occurrence and risk assessment of 2,4-dinitrophenol (2,4-DNP), phenol (PHE), and 2,4,6-trichlorophenol (2,4,6-TCP) in drinking water sources in three south-western States in Nigeria (Osun, Oyo, and Lagos). Groundwater (GW) and surface water (SW) were collected during dry and rainy seasons of a year. The detection frequency of the phenolic compounds followed the trend Phenol > 2,4-DNP > 2,4,6-TCP. The mean concentrations of 2,4-DNP, Phenol, and 2,4,6-TCP in GW/SW samples from Osun State were 639/553 μg L, 261/262 μg L, and 169/131 μg L during the rainy season and 154/7 μg L, 78/37 μg L, and 123/15 μg L during the dry season, respectively. In Oyo State, the mean concentrations were 165/391 μg L for 2,4-DNP and 71/231 μg L for Phenol in GW/SW samples, respectively, during the rainy season. Generally, in the dry season, these values decreased. In any case, these concentrations are higher than those previously reported in water from other countries. The concentration of 2,4-DNP in water posed serious ecological risks to Daphnia on the acute scale while it was algae on the chronic scale. Estimated daily intake and hazard quotient calculations suggest that 2,4-DNP and 2,4,6-TCP in water pose serious toxicity concerns to humans. Additionally, the concentration of 2,4,6-TCP in water from Osun State in both seasons of the year and in both groundwater and surface water poses significant carcinogenic risks to persons ingesting water from these sources in the State. Every exposure group studied were at risk from ingesting these phenolic compounds in water. However, this risk decreased with increasing age of the exposure group. Results from the principal component analysis indicate that 2,4-DNP in water samples is from an anthropogenic source different from that for Phenol and 2,4,6-TCP. There is a strong need to treat water from GW and SW systems in these States before ingesting while assessing their quality regularly.
Topics: Humans; 2,4-Dinitrophenol; Drinking Water; Environmental Monitoring; Groundwater; Nigeria; Phenol; Phenols; Risk Assessment; Water Pollutants, Chemical
PubMed: 37246181
DOI: 10.1007/s11356-023-27622-w