The Health Risk Associated with Chronic Diseases in Villages with High Arsenic Levels in Drinking Water Supplies

The microcystins are produced by several species of common planktonic cyanobacteria found in surface waters, but their biological function remains unknown. The microcystins have been shown to be extremely potent hepatotoxins in a variety of experimental animals and they are lethal at low doses. Microcystin-LR, one of over 40 microcystin analogues, has also been shown to be a potent tumor promoter. The toxic effects of the microcystins have been attributed to the inhibition of protein phosphatases. This inhibition causes collapse of the cytoskeleton and interferes with a general signal transduction mechanism in cells. The presence of toxic cyanobacteria in surface water has been documented in all parts of the world. The microcystins have been related to a few incidents of human illness and several incidents of animal poisoning in Canada, United States, Australia, Europe, and Africa. Therefore, exposure to the microcystins is a potentially significant health risk and toxin removal from drinking water is becoming a concern worldwide. Conventional water treatment processes (coagulation/sedimentation, chlorination) have generally proven ineffective at removing microcystin toxins from drinking water. Activated carbon, ozone, and free chlorine have been effective in removing microcystins below detectable concentrations in laboratory experiments. Considering these factors, the occurrence of microcystins in drinking water supplies deserves serious attention to insure that adverse health effects are prevented.Key words: microcystins, hepatotoxins, cyanobacteria, blue-green algae, water treatment, health risk.

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Determination of cytotoxicity and invasiveness of heterotrophic plate count bacteria isolated from drinking water

Water Science & Technology Water Supply ◽

10.2166/ws.2002.0093 ◽

2002 ◽

Vol 2 (3) ◽

pp. 115-122 ◽

Cited By ~ 3

Author(s):

D. Pavlov ◽

C.M.E. de Wet ◽

W.O.K. Grabow ◽

M.M. Ehlers

Keyword(s):

Drinking Water ◽

Health Risk ◽

Heterotrophic Bacteria ◽

Penicillin G ◽

Plate Count ◽

Heterotrophic Plate Count ◽

Water Supplies ◽

Plate Counts ◽

Study Support ◽

Heterotrophic Plate Counts

Evidence has been presented that some heterotrophic bacteria often detected in drinking water supplies possess features associated with pathogenicity. This suggests that even the low numbers of heterotrophic bacteria considered acceptable by drinking water specifications may constitute a health risk, particularly to immunocompromised consumers. In this study, 339 bacteria were isolated at random from routine heterotrophic plate count (HPC) tests on selected drinking water supplies in South Africa. In a first screen for potentially pathogenic properties, 188 of the isolates (55.5%) displayed a- or b-haemolysis on blood agar. Further analysis of the haemolytic isolates for enzymes associated with virulence revealed the presence of chondroitinase (5.3%), coagulase (16.0%), DNase (60.6%), elastase (33.0%), fibrinolysin (53.7%), gelatinase (62.2%), hyaluronidase (21.3%), lecithinase (47.9%), lipase (54.8%) and proteinase (64.4%) of the isolates. No fluorescein or pyocyanin was detected in any of the isolates. Among the haemolytic isolates 68.6% were resistant to oxacillin (1 μg), 59.6% to penicillin G (2 units), 47.3% to penicillin G (10 units), 53.7% to ampicillin (10 μg) and 42.6% to ampicillin (25 μg). Cytotoxicity, invasiveness and adherence properties of the haemolytic isolates was determined on HEp-2 and Caco2 cell lines. Among the haemolytic isolates 96% were cytolytic on the HEp-2 cell line. All the haemolytic isolates adhered to HEp-2 and Caco2 cells but gram-negative isolates tended to adhere in larger numbers than gram-positive isolates. HEp-2 cells were invaded by 42% of the haemolytic isolates. Heterotrophic bacteria, which most frequently revealed the above features associated with pathogenicity included species of the following genera: Aeromonas, Acinetobacter, Aureobacterium, Bacillus, Klebsiella, Moraxella, Pseudomonas, Staphylococcus, Tsukamurella and Vibrio. The results obtained in this study support earlier indications that bacteria detected by routine heterotrophic plate counts on drinking water supplies may include bacteria associated with potentially pathogenic properties. The extent to which these bacteria in drinking water supplies may constitute a health risk remains to be investigated.

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Statistical Analysis of Causes of Death (2005–2010) in Villages of Simav Plain, Turkey, With High Arsenic Levels in Drinking Water Supplies

Archives of Environmental & Occupational Health ◽

10.1080/19338244.2013.872076 ◽

2014 ◽

Vol 70 (1) ◽

pp. 35-46 ◽

Cited By ~ 15

Author(s):

Orhan Gunduz ◽

Coskun Bakar ◽

Celalettin Simsek ◽

Alper Baba ◽

Alper Elci ◽

...

Keyword(s):

Drinking Water ◽

Statistical Analysis ◽

Causes Of Death ◽

Water Supplies ◽

High Arsenic

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Monitoring, mapping and health risk assessment of fluoride in drinking water supplies in rural areas of Maku and Poldasht, Iran

Environmental Geochemistry and Health ◽

10.1007/s10653-019-00282-x ◽

2019 ◽

Vol 41 (5) ◽

pp. 2281-2294

Author(s):

Hassan Aslani ◽

Mahsa Zarei ◽

Hassan Taghipour ◽

Ehsan Khashabi ◽

Hossein Ghanbari ◽

...

Keyword(s):

Risk Assessment ◽

Drinking Water ◽

Health Risk ◽

Health Risk Assessment ◽

Rural Areas ◽

Water Supplies

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Significance of private water supply wells in a rural Nevada area as a route of exposure to aqueous arsenic

Journal of Water and Health ◽

10.2166/wh.2005.044 ◽

2005 ◽

Vol 3 (3) ◽

pp. 305-312 ◽

Cited By ~ 10

Author(s):

Mark Walker ◽

Marnee Benson ◽

W. Douglass Shaw

Keyword(s):

Drinking Water ◽

Water Supply ◽

Rural Areas ◽

Tap Water ◽

Water Supplies ◽

Educational Effort ◽

Adverse Health Effects ◽

Route Of Exposure ◽

Private Wells ◽

High Arsenic

In many rural areas domestic drinking water needs are met by a mixture of public water supplies and private water supplies. Private supplies are not subject to the regulations and management requirements of the Safe Drinking Water Act (SDWA). Amendments to the SDWA recently lowered the standard for arsenic from 50 to 10 ppb in public water supplies (effective in 2006). Churchill County, Nevada, has approximately 25,000 residents. Slightly more than half (13,500) rely on private domestic wells for water supply. Ample data and media publicity about high arsenic concentrations in water supplies and a federally led investigation of a leukaemia cluster suggested that residents of the county would be aware that arsenic concentrations in private wells were highly likely to exceed the 10 ppb standard. A survey carried out in 2002 showed that a majority of respondents (72%) consumed water from private wells and among them a minority (38%) applied treatment. Maximum, median and minimum concentrations of arsenic from all samples (n = 351) were 2,100, 26 and <3 ppb, respectively. Seventy-four per cent of all samples exceeded 10 ppb. A majority (87%) of those who applied treatment consumed tap water. The relatively low rate of application of treatment suggested that these rural residents did not recognize that consumption could have associated health risks. However, those who applied treatment were ∼0.3 times as likely to be consuming water with > 10 ppb arsenic than those who consumed water that was not treated. In areas where concentrations of arsenic have been demonstrated to be high, it may be important to conduct a focused educational effort for private well owners to ensure that they take the steps needed to assess and reduce risks associated with contaminants found in tap water, including arsenic. An educational effort could include promoting sampling efforts to determine the magnitude of arsenic concentrations, explaining the risk associated with arsenic consumption and providing information about choices for home treatment systems that are likely to be effective in removing arsenic. This may be especially important in rural areas where adverse health effects are not evident to local populations.

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Arsenic in private drinking water supplies: human health risk based on underlying geology

ISEE Conference Abstracts ◽

10.1289/isee.2013.p-1-10-05 ◽

2013 ◽

Vol 2013 (1) ◽

pp. 4527

Author(s):

Helen Crabbe ◽

Rebecca Close ◽

Mike Studden ◽

Pauline Smedley ◽

Louise Ander ◽

...

Keyword(s):

Drinking Water ◽

Health Risk ◽

Human Health ◽

Human Health Risk ◽

Water Supplies

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Enteric viruses in drinking water supplies

Water Science & Technology Water Supply ◽

10.2166/ws.2002.0080 ◽

2002 ◽

Vol 2 (3) ◽

pp. 17-22

Author(s):

A.P. Wyn-Jones ◽

J. Watkins ◽

C. Francis ◽

M. Laverick ◽

J. Sellwood

Keyword(s):

Drinking Water ◽

Heavy Rainfall ◽

Liquid Culture ◽

Plaque Assay ◽

Enteric Viruses ◽

Enteric Virus ◽

The Other ◽

Raw Water ◽

Rt Pcr ◽

Water Supplies

Two rural spring drinking water supplies were studied for their enteric virus levels. In one, serving about 30 dwellings, the water was chlorinated before distribution; in the other, which served a dairy and six dwellings the water was not treated. Samples of treated (40 l) and untreated (20 l) water were taken under normal and heavy rainfall conditions over a six weeks period and concentrated by adsorption/elution and organic flocculation. Infectious enterovirus in concentrates was detected in liquid culture and enumerated by plaque assay, both in BGM cells, and concentrates were also analysed by RT-PCR. Viruses were found in both raw water supplies. Rural supplies need to be analysed for viruses as well as bacterial and protozoan pathogens if the full microbial hazard is to be determined.

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The assessment of biofilm community composition on plumbing materials in filtered and unfiltered water distribution systems

Water Science & Technology Water Supply ◽

10.2166/ws.2003.0102 ◽

2003 ◽

Vol 3 (1-2) ◽

pp. 187-191

Author(s):

M.M. Critchley ◽

N.J. Cromar ◽

H.J. Fallowfield

Keyword(s):

Drinking Water ◽

Fatty Acid ◽

Community Composition ◽

Distribution Systems ◽

Water Distribution ◽

Water Distribution Systems ◽

Polymer Materials ◽

Fatty Acid Profiles ◽

Water Supplies ◽

Drinking Water Distribution Systems

Biofilms have been extensively characterised within drinking water distribution systems. However, the significance of materials on biofilm species diversity is not established. This study investigated the community composition of biofilms on plumbing materials receiving filtered and unfiltered water supplies. Biofilms were extracted from polybutylene, polyethylene, cross-linked polyethylene, unplasticised polyvinyl chloride and copper tubes in sampling rigs receiving Murray-Onkaparinga water before or after filtration. Biofilms were extracted and analysed for fatty acid composition using the FAME™ methodology. There were differences in the fatty acid profiles of biofilms and the respective water supplies, indicating differences in the attached and planktonic communities. The results also showed significant differences in the fatty acid profiles of biofilms on the polymer materials compared to copper, suggesting variations in biofilm populations on the different materials. The potential for materials to select for microbial populations has significant implications for the ecology of drinking water biofilms.

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Water Quality and Health

Water Science & Technology ◽

10.2166/wst.1991.0416 ◽

1991 ◽

Vol 23 (1-3) ◽

pp. 201-209 ◽

Cited By ~ 4

Author(s):

W. Kreisel

Keyword(s):

Water Quality ◽

Developing Countries ◽

Drinking Water ◽

Water Supply ◽

Human Health ◽

Pollution Control ◽

Wastewater Reuse ◽

Water Supplies ◽

Minimum Quality Standards ◽

Quality Guidelines

Water quality can affect human health in various ways: through breeding of vectors, presence of pathogenic protozoa, helminths, bacteria and viruses, or through inorganic and organic chemicals. While traditional concern has been with pathogens and gastro-intestinal diseases, chemical pollutants in drinking-water supplies have in many instances reached proportions which affect human health, especially in cases of chronic exposure. Treatment of drinking-water, often grossly inadequate in developing countries, is the last barrier of health protection, but control at source is more effective for pollution control. Several WHO programmes of the International Drinking-Water Supply and Sanitation Decade have stimulated awareness of the importance of water quality in public water supplies. Three main streams have been followed during the eighties: guidelines for drinking-water quality, guidelines for wastewater reuse and the monitoring of freshwater quality. Following massive investments in the community water supply sector to provide people with adequate quantities of drinking-water, it becomes more and more important to also guarantee minimum quality standards. This has been recognized by many water and health authorities in developing countries and, as a result, WHO cooperates with many of them in establishing water quality laboratories and pollution control programmes.

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