-
Environmental Research Jul 2022Pollution of water sources, largely from wide-scale agricultural fertilizer use has resulted in nitrate and nitrite contamination of drinking water. The effects on human... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Pollution of water sources, largely from wide-scale agricultural fertilizer use has resulted in nitrate and nitrite contamination of drinking water. The effects on human health of raised nitrate and nitrite levels in drinking water are currently unclear.
OBJECTIVES
We conducted a systematic review of peer-reviewed literature on the association of nitrate and nitrite in drinking water with human health with a specific focus on cancer.
METHODS
We searched eight databases from 1 January 1990 until 28 February 2021. Meta-analyses were conducted when studies had the same exposure metric and outcome.
RESULTS
Of 9835 studies identified in the literature search, we found 111 studies reporting health outcomes, 60 of which reported cancer outcomes (38 case-control studies; 12 cohort studies; 10 other study designs). Most studies were set in the USA (24), Europe (20) and Taiwan (14), with only 3 studies from low and middle-income countries. Nitrate exposure in water (59 studies) was more commonly investigated than nitrite exposure (4 studies). Colorectal (15 studies) and gastric (13 studies) cancers were the most reported. In meta-analyses (4 studies) we identified a positive association of nitrate exposure with gastric cancer, OR = 1.91 (95%CI = 1.09-3.33) per 10 mg/L increment in nitrate ion. We found no association of nitrate exposure with colorectal cancer (10 studies; OR = 1.02 [95%CI = 0.96-1.08]) or cancers at any other site.
CONCLUSIONS
We identified an association of nitrate in drinking water with gastric cancer but with no other cancer site. There is currently a paucity of robust studies from settings with high levels nitrate pollution in drinking water. Research into this area will be valuable to ascertain the true health burden of nitrate contamination of water and the need for public policies to protect human health.
Topics: Drinking Water; Humans; Nitrates; Nitrites; Nitrogen Oxides; Stomach Neoplasms
PubMed: 35217009
DOI: 10.1016/j.envres.2022.112988 -
International Journal of Environmental... Jan 2021The ubiquitous problem of pesticide in aquatic environment are receiving worldwide concern as pesticide tends to accumulate in the body of the aquatic organism and... (Review)
Review
The ubiquitous problem of pesticide in aquatic environment are receiving worldwide concern as pesticide tends to accumulate in the body of the aquatic organism and sediment soil, posing health risks to the human. Many pesticide formulations had introduced due to the rapid growth in the global pesticide market result from the wide use of pesticides in agricultural and non-agricultural sectors. The occurrence of pesticides in the water body is derived by the runoff from the agricultural field and industrial wastewater. Soluble pesticides were carried away by water molecules especially during the precipitation event by percolating downward into the soil layers and eventually reach surface waters and groundwater. Consequently, it degrades water quality and reduces the supply of clean water for potable water. Long-time exposure to the low concentration of pesticides had resulted in non-carcinogenic health risks. The conventional method of pesticide treatment processes encompasses coagulation-flocculation, adsorption, filtration and sedimentation, which rely on the phase transfer of pollutants. Those methods are often incurred with a relatively high operational cost and may cause secondary pollution such as sludge formation. Advanced oxidation processes (AOPs) are recognized as clean technologies for the treatment of water containing recalcitrant and bio-refractory pollutants such as pesticides. It has been adopted as recent water purification technology because of the thermodynamic viability and broad spectrum of applicability. This work provides a comprehensive review for occurrence of pesticide in the drinking water and its possible treatment.
Topics: Agriculture; Drinking Water; Environmental Monitoring; Groundwater; Humans; Pesticides; Water Pollutants, Chemical
PubMed: 33430077
DOI: 10.3390/ijerph18020468 -
International Maritime Health 2020Ships are supplied with water from various sources: directly from the public utility system at the port, from water supply vessels or barges, bottled water, ice or, if... (Review)
Review
BACKGROUND
Ships are supplied with water from various sources: directly from the public utility system at the port, from water supply vessels or barges, bottled water, ice or, if water production on board is possible,through processes such as desalination and reverse osmosis. All elements of a ship's water supply chain are exposed to the influence of different factors that may have a negative impact on water safety on board or on human health. Potable water standards are the same for vessels and for land-based facilities. In recognition of the importance of drinking water and the impact it can have on human health, stringent quality standards have been laid down in national and global regulations. The aim of the study was to describe the water supply system on ships and its weak points, as well as the health risks that the use of npolluted drinking water can entail.
MATERIALS AND METHODS
The Medline Database has been searched using the following key words: ship, water supply, waterborne infections. Other available literature has also been used, as well as national and international regulations on drinking-water safety.
RESULTS AND CONCLUSIONS
Drinking water on ships is managed in line with the hygienic and health standards applied along the entire supply chain, from the source to the point of consumption. Regardless of the sanitary control system used by the authorised institutions on the ground, ship officers must oversee the entire water supply and distribution system on board, as well the water production systems if these exist. That means that they must be well aware of all of the fundamental facts of the supervision system, as well as the weaknesses of the water supply system. Maritime studies students, future deck officers and engine officers, must all receive training on the weak points of the system and on water contamination prevention.
Topics: Drinking Water; Naval Medicine; Ships; Water Microbiology; Water Quality; Water Supply
PubMed: 32604456
DOI: 10.5603/IMH.2020.0022 -
Water Research May 2023Drinking water treatment plants (DWTPs) are designed to remove physical, chemical, and biological contaminants. However, until recently, the role of DWTPs in minimizing...
Drinking water treatment plants (DWTPs) are designed to remove physical, chemical, and biological contaminants. However, until recently, the role of DWTPs in minimizing the cycling of antibiotic resistance determinants has got limited attention. In particular, the risk of selecting antibiotic-resistant bacteria (ARB) is largely overlooked in chlorine-free DWTPs where biological processes are applied. Here, we combined high-throughput quantitative PCR and metagenomics to analyze the abundance and dynamics of microbial communities, antibiotic resistance genes (ARGs), and mobile genetic elements (MGEs) across the treatment trains of two chlorine-free DWTPs involving dune-based and reservoir-based systems. The microbial diversity of the water increased after all biological unit operations, namely rapid and slow sand filtration (SSF), and granular activated carbon filtration. Both DWTPs reduced the concentration of ARGs and MGEs in the water by circa 2.5 log gene copies mL, despite their relative increase in the disinfection sub-units (SSF in dune-based and UV treatment in reservoir-based DWTPs). The total microbial concentration was also reduced (2.5 log units), and none of the DWTPs enriched for bacteria containing genes linked to antibiotic resistance. Our findings highlight the effectiveness of chlorine-free DWTPs in supplying safe drinking water while reducing the concentration of antibiotic resistance determinants. To the best of our knowledge, this is the first study that monitors the presence and dynamics of antibiotic resistance determinants in chlorine-free DWTPs.
Topics: Drinking Water; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Bacteria; Genes, Bacterial; Anti-Bacterial Agents; Water Purification; Chlorine; Microbiota
PubMed: 36989799
DOI: 10.1016/j.watres.2023.119905 -
International Journal of Environmental... Dec 2022This study identified and mapped worldwide surveillance actions and initiatives of drinking water quality implemented by government agencies and public health services.... (Review)
Review
This study identified and mapped worldwide surveillance actions and initiatives of drinking water quality implemented by government agencies and public health services. The scoping review was conducted between July 2021 and August 2022 based on the Joanna Briggs Institute method. The search was performed in relevant databases and gray literature; 49 studies were retrieved. Quantitative variables were presented as absolute and relative frequencies, while qualitative variables were analyzed using the IRaMuTeQ software. The actions developed worldwide and their impacts and results generated four thematic classes: (1) assessment of coverage, accessibility, quantity, and drinking water quality in routine and emergency situations; (2) analysis of physical-chemical and microbiological parameters in public supply networks or alternative water supply solutions; (3) identification of household water contamination, communication, and education with the community; (4) and investigation of water-borne disease outbreaks. Preliminary results were shared with stakeholders to favor knowledge dissemination.
Topics: Drinking Water; Water Quality; Water Supply; Water Pollution; Disease Outbreaks
PubMed: 36612879
DOI: 10.3390/ijerph20010559 -
Environment International Jan 2022Climate change, severe droughts, population growth, demand increase, and poor management during the recent decades have further stressed the scarce freshwater resources...
Climate change, severe droughts, population growth, demand increase, and poor management during the recent decades have further stressed the scarce freshwater resources worldwide and resulted in severe water shortages in many regions. The water utilities address the water shortage by providing alternative source of water, augment the supplied water, supply intermittently, and even bulk water delivery under severe water shortage conditions. On the other hand, many households store water in building storage tanks to cope with insufficient delivery of potable water due to frequent interruptions. All these practices could pose crucial risks to the chemical and microbiological quality of the water. However, consistent monitoring and implementation of mitigation strategies could lower the potential risks associated with these practices. It is critical to identify the potential hazards resulting from the alternative water supplies and distribution practices to develop temporary and long-term monitoring and mitigation plans and reduce the microbial and chemical contamination of potable water delivered to the consumers. This paper provides a holistic review of the significant hazards associated with the practices employed by the water utilities and water consumers to alleviate the potable water shortage and discusses the required monitoring and mitigation practices.
Topics: Climate Change; Drinking Water; Water Supply
PubMed: 34655888
DOI: 10.1016/j.envint.2021.106936 -
Chemosphere Dec 2020Over the last 30 years, bottled water has gained in popularity reaching high sales world-wide. Most of this water is sold in polyethylene terephthalate (PET) bottles.... (Review)
Review
Over the last 30 years, bottled water has gained in popularity reaching high sales world-wide. Most of this water is sold in polyethylene terephthalate (PET) bottles. About 15 years ago, the presence of antimony in water in those PET bottles raised concerns and studies on the subject have been regularly published since then. This review aims to evaluate whether the use of good analytical practices and the correct design of these studies support the accepted facts (i.e., PET is the origin of antimony presence in bottled waters, antimony concentrations are usually below regulated values, temperature increasing favours antimony leaching). The detailed analysis of published data has confirmed these facts but has also revealed frequency of faulty analytical practices and a lack of well-designed studies. A better understanding of the structure of PET polymer in the bottles, coupled with statistically-robust antimony release experiments, is required to progress in the field.
Topics: Antimony; Drinking Water; Food Contamination; Food Packaging; Polyethylene Terephthalates; Temperature; Time Factors; Water Pollutants, Chemical
PubMed: 32739689
DOI: 10.1016/j.chemosphere.2020.127732 -
Annals of Nutrition & Metabolism 2020
Topics: Congresses as Topic; Drinking; Drinking Behavior; Drinking Water; Health Status; Humans; Organism Hydration Status; Water Resources; Water Supply
PubMed: 33761500
DOI: 10.1159/000515017 -
Water Research Jul 2022Samples from fifty-five surface water resources and twenty-five drinking water treatment plants in Europe, Africa, Asia, and USA were used to analyse the fluorescence...
Samples from fifty-five surface water resources and twenty-five drinking water treatment plants in Europe, Africa, Asia, and USA were used to analyse the fluorescence composition of global surface waters and predict aromaticity and treatability from fluorescence excitation emission matrices. Nine underlying fluorescence components were identified in the dataset using parallel factor analysis (PARAFAC) and differences in aromaticity and treatability could be predicted from ratios between components H (λ/λ= 395/521), H (λ/λ= 330/404), P, (λ/λ=290/365) and P (λ/λ= 275/302). Component H tracked humic acids of primarily plant origin, H tracked weathered/oxidised humics and the "building block" fraction measured by LC-OCD, while P and P tracked amino acids in the "low molecular weight neutrals" LC-OCD fraction. Ratios between PARAFAC components predicted DOC removal at lab scale for French rivers in standardized tests involving coagulation, powdered activated carbon (PAC), chlorination, ion exchange (IEX), and ozonation, alone and in combination. The ratio H/H, for convenience named "PARIX" standing for "PARAFAC index", predicted SUVA according to a simple relationship: SUVA = 4.0 x PARIX (RMSEp=0.55) Lmgm. These results expand the utility of fluorescence spectroscopy in water treatment applications, by demonstrating the existence of previously unknown relationships between fluorescence composition, aromaticity and treatability that appear to hold across diverse surface waters at various stages of drinking water treatment.
Topics: Dissolved Organic Matter; Drinking Water; Factor Analysis, Statistical; Humic Substances; Rivers; Spectrometry, Fluorescence; Water Purification
PubMed: 35613481
DOI: 10.1016/j.watres.2022.118592 -
Environmental Science & Technology Mar 2023The biogeography of eukaryotes in drinking water systems is poorly understood relative to that of prokaryotes or viruses, limiting the understanding of their role and...
The biogeography of eukaryotes in drinking water systems is poorly understood relative to that of prokaryotes or viruses, limiting the understanding of their role and management. A challenge with studying complex eukaryotic communities is that metagenomic analysis workflows are currently not as mature as those that focus on prokaryotes or viruses. In this study, we benchmarked different strategies to recover eukaryotic sequences and genomes from metagenomic data and applied the best-performing workflow to explore the factors affecting the relative abundance and diversity of eukaryotic communities in drinking water distribution systems (DWDSs). We developed an ensemble approach exploiting -mer- and reference-based strategies to improve eukaryotic sequence identification and identified MetaBAT2 as the best-performing binning approach for their clustering. Applying this workflow to the DWDS metagenomes showed that eukaryotic sequences typically constituted small proportions (i.e., <1%) of the overall metagenomic data with higher relative abundances in surface water-fed or chlorinated systems with high residuals. The α and β diversities of eukaryotes were correlated with those of prokaryotic and viral communities, highlighting the common role of environmental/management factors. Finally, a co-occurrence analysis highlighted clusters of eukaryotes whose members' presence and abundance in DWDSs were affected by disinfection strategies, climate conditions, and source water types.
Topics: Drinking Water; Metagenome; Eukaryota; Metagenomics
PubMed: 36827617
DOI: 10.1021/acs.est.2c09010