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POST a QUESTION or COMMENT about total coliform and E-coli test results, standards, interpretation, action for drinking water or well water;
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Standards for Coliform in Drinking Water
Question: is our water safe to drink if coliform is detected?
2018/10/16 Pradeep said:
I have tested our drinking well water. In it the total Coliforms MPN/ 100 ml is 1600, Thermotolerant coliforms MP N/ 100 ml is 175, and Escherichia coli MP N/ 100 ml is less than 2.
Is the water good for drinking and how can we get the waterpurified?
Our photo at page top shows a typical water bacteria test bottle. Our photo just above shows an un-sanitary drinking water well found by th author [DF] at an inspection in New York.
Reply: no coliform should be found (0 per 100 ml) in drinking water.
No Pradeep, by US standards and those used in some other countries,
Coliform limits in drinking water: The Maximum Acceptable Concentration of both Total Coliforms and E-Coli for Drinking Water is ** none detectable per 100 mL **
This means that for every 100 mL of drinking water tested, NO total coliforms and NO E.coli should be detected.
While total coliform is common in groundwater and is not necessarily harmful itself, when it is found in drinking water it should be understood to be an indicator that unsanitary water is entering the water supply.
When E-coli (E.coli or Escherichia coli) is present in drinking water it is harmful, containing pathogens that can cause serious illness, and is even more dangerous for people who have a weakened immune system. .
Escherichia coli (abbreviated as E. coli) are bacteria found in the environment, foods, and intestines of people and animals. E. coli are a large and diverse group of bacteria.
Although most strains of E. coli are harmless, others can make you sick.
Some kinds of E. coli can cause diarrhea (Diarrheagenic E. coli), while others cause urinary tract infections, respiratory illness and pneumonia, and other illnesses [Enterotoxigenic E. coli (ETEC) and Shiga toxin-producing E. coli (STEC) - Ed.]. - E.coli (Escherichia coli), US CDC, retrieved 2018/10/16, original source: https://www.cdc.gov/ecoli/index.html
For a guide to interpreting the results of a water test for bacteria you should also read WATER TEST INTERPRETATION.
For details about how to conduct bacteria testing in the water supply you may want to read BACTERIA TEST GUIDE - tests the level of microbial ccontaminants in water.
Coliform Standards for Drinking Water - by Country
Canadian Standards for Coliform Levels in Drinking Water
The Canadian Drinking Water Quality Guideline for total coliforms is none detectable per 100 mL.
The Canadian Drinking Water Quality Guideline for Escherichia coli (E.coli) is none detectable per 100 mL.
Maximum Acceptable Concentration for Drinking Water = none detectable per 100 mL
According to the Mexican constitution responsibility for water supply and sanitation services delivery rests with 2,517 municipalities since the decentralization of 1983. (Pablos 2002)
Este artículo presenta la evolución institucional y legal
del servicio urbano de agua potable en México durante
la segunda mitad del siglo X X.Además de ofrecer
un breve esquema de análisis de la política pública, en
la parte principal se proponen tres etapas esenciales
por la que ha pasado esta política.
Dichas etapas se
basan en el tipo de arreglo institucional que caracterizó
a la prestación del servicio de agua potable en cada
periodo.
La primera es la etapa centralista de las juntas
federales de agua , prevaleciente de 1948 a 1983;
después
viene la etapa de la municipalización, iniciada en
1983 en que el servicio se asigna a los gobiernos locales
y,
en tercer lugar, está la promoción de organismos
operado res autónomos y manejados como empresas,
iniciada por la Comisión Nacional del Agua a partir de
1989 .
Al final, se revisan las vicisitudes del impulso a la
participación del sector pri vado en el servicio urbanode agua y el trastorno que éste tuvo ante la crisis económica
de 1995.
WATER QUALITY, SANITATION TECHNOLOGY FOR THE AMERICAS [PDF] (1996-2018) Mexican Official Standard NOM-001-ECOL-1996 - Cepis retrieved 2018/10/16, original source: http://cepis.org.pe/mexican-official-standard-001ecol1996/
This Mexican Official Standard establishes the maximum permissible limits of pollutants in discharges of wastewater dumped into national waters and goods, in order to protect its quality and enable their uses, and is mandatory for those responsible for such discharges.
This Mexican Official Standard does not apply to discharges of water from separate storm drainage.
Esta Norma Oficial Mexicana establece los límites máximos permisibles de contaminantes en las descargas de aguas residuales vertidas a aguas y bienes nacionales, con el objeto de proteger su calidad y posibilitar sus usos, y es de observancia obligatoria para los responsables de dichas descargas.
Esta Norma Oficial Mexicana no se aplica a las descargas de aguas provenientes de drenajes pluviales independientes.
UK United Kingdom Drinking Water Standards including for Coliform
These standards include coliform and E-coli and require that both be at a level of zero at consumer taps: 0/100 ml. for Enterococci, Escherichia coli.
United States Standards for Coliform in Drinking Water
Excerpts:
For E. coli (EC), the Maximum Contaminant Level Goal (MCLG) is set at zero.
Total coliforms are a group of related bacteria that are (with few exceptions) not harmful to humans. A variety of bacteria, parasites, and viruses, known as pathogens, can potentially cause health problems if humans ingest them.
EPA considers total coliforms a useful indicator of other pathogens for drinking water.
Total coliforms are used to determine the adequacy of water treatment and the integrity of the distribution system.
TOTAL COLIFORM RULE: A QUICK REFERENCE GUIDE [PDF] US EPA, Total Coliform Rule (TCR)
54 FR 27544-27568, June 29, 1989, Vol. 54, No. 1241 - retrieved 2018/10/16, original source: nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=3000663W.txt
DRINKING WATER REGULATIONS, U.S. [Website] The complete regulations regarding these contaminants available from the Code of Federal Regulations Website -(United States)
DRINKING WATER CONTAMINANT WATER LIMITS [InspectApedia.com article] - what are the maximum allowed or limits on various contaminants found in drinking water. Health Effects of Chemical Contaminants in Drinking Water, US Environmental Protection Agency, others.
Watch out: people with weakened immune systems may be more vulnerable to pathogens or other contaminants in drinking water. Treatments that kill coliform bacteria are generally not effective against other pathogens that may be present. See:
Excerpts: Cryptosporidium is a parasite commonly found in lakes and rivers, especially when the water is contaminated
with sewage and animal wastes.
Cryptosporidium is very resistant to disinfection, and even a well-operated water
treatment system cannot ensure that drinking water will be completely free of this parasite.
Current EPA drinking
water standards were not explicitly designed to assure the removal or killing of Cryptosporidium.
Many large
water systems already [in 1995] voluntarily take actions for greater control of Cryptosporidium and other microbial
contaminants.
By 2001, the water systems serving the majority of the United States population (those relying on a
surface water source, such as a river, and serving more than 10,000 people) must meet a new [in 1995] EPA standard that
strengthens control over microbial contaminants, including Cryptosporidium. EPA continues to conduct research
on microbial contaminants which will be used for determining priorities for the drinking water program,
including setting future standards and reevaluating existing standards.
Cryptosporidium has caused several large waterborne disease outbreaks of gastrointestinal illness, with
symptoms that include diarrhea, nausea, and/or stomach cramps.
People with severely weakened immune systems
(that is, severely immunocompromised) are likely to have more severe and more persistent symptoms than
healthy individuals. Moreover, Cryptosporidium has been a contributing cause of death in some immunocompromised
people.
Individuals who are severely immunocompromised may include those who are infected
with HIV/AIDS, cancer and transplant patients taking immunosuppressive drugs, and people born with a
weakened immune system.
WHO World Health Organization Drinking Water Guidelines & Coliform Standards
Excerpts Significance in drinking-water
Total coliforms should be absent immediately after disinfection, and the presence of
these organisms indicates inadequate treatment.
The presence of total coliforms in
distribution systems and stored water supplies can reveal regrowth and possible
biofilm formation or contamination through ingress of foreign material, including
soil or plants.
While E.
coli is a useful indicator, it has limitations.
Enteric viruses and protozoa are more
resistant to disinfection; consequently, the absence of E. coli will not necessarily indicate
freedom from these organisms.
Under certain circumstances, it may be desirable
to include more resistant microorganisms, such as bacteriophages and/or bacterial
spores.
Such circumstances could include the use of source water known to be contaminated
with enteric viruses and parasites or high levels of viral and parasitic diseases
in the community.
Vol. 1 Addendum, RECOMMENDATIONS, MICROBIOLOGICAL AGENTS in DRINKING WATER PDF] discusses Aeromonas, Enteric hepatitis viruses, Legionella, Protozoan parasites ( Cryptosporidium, Giardia,
Cyclospora) - retrieved 2018/10/16, original source: apps.who.int/iris/bitstream/handle/10665/42852/9241546387.pdf?sequence=1&isAllowed=y
If coliform is the only contaminant in drinking water AND after establishing that you can't correct the problem by shocking the well and fixing surface water leaks into the well then you will want to install a water disinfection system.
Watch out: before installing any water treatment system for bacteria you should have more-extensive water testing done to find out if there are other non-bacterial contaminants that also need to be removed.
That's because the presence of coliform in drinking water often means that surface water is leaking into the water supply.
When surface runoff leaks into a drinking water supply, any contaminants present on the surface, including for example pesticides or agricultural chemicals, are likely to be in the water and also are likely to be at levels meriting removal.
...
Continue reading at WATER TEST RESULT INTERPRETATION - what the results mean and what to do about them , or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.
WATER TESTING ADVICE - for home buyers
and building owners: water contaminants, water test procedures, well shock procedures, preventing drinking water
contamination,
CHEATING ON WATER TESTS - warns about how people accidentally or on purpose can obtain incorrect water test results.
Or see WATER TREATMENT EQUIPMENT CHOICES - home- options for water disinfection, treatment, purification, or removal of other un-wanted substances
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In addition to any citations in the article above, a full list is available on request.
Allaire, Maura, Haowei Wu and Upmanu Lall, "National trends in drinking water quality violationsNational trends in drinking water quality violations", PNAS 2018; published ahead of print February 12, 2018, https://doi.org/10.1073/pnas.1719805115
Abstract
Ensuring safe water supply for communities across the United States is a growing challenge in the face of aging infrastructure, impaired source water, and strained community finances. In the aftermath of the Flint lead crisis, there is an urgent need to assess the current state of US drinking water. However, no nationwide assessment has yet been conducted on trends in drinking water quality violations across several decades.
Efforts to reduce violations are of national concern given that, in 2015, nearly 21 million people relied on community water systems that violated health-based quality standards. In this paper, we evaluate spatial and temporal patterns in health-related violations of the Safe Drinking Water Act using a panel dataset of 17,900 community water systems over the period 1982–2015. We also identify vulnerability factors of communities and water systems through probit regression.
Increasing time trends and violation hot spots are detected in several states, particularly in the Southwest region. Repeat violations are prevalent in locations of violation hot spots, indicating that water systems in these regions struggle with recurring issues.
In terms of vulnerability factors, we find that violation incidence in rural areas is substantially higher than in urbanized areas. Meanwhile, private ownership and purchased water source are associated with compliance.
These findings indicate the types of underperforming systems that might benefit from assistance in achieving consistent compliance. We discuss why certain violations might be clustered in some regions and strategies for improving national drinking water quality.
Ohio State University article on the concentration of chlorine necessary to act as an effective disinfectant, and the effects of the water's pH and temperature: See http://ohioline.osu.edu/b795/b795_7.html for details.
Our Stolen Future: Are We Threatening Our Fertility, Intelligence, and Survival?--A Scientific Detective Story, Theo Colborn, Dianne Dumanoski, John Peter Meyers. Plume-Penguin Publishing, 1997, ISBN 0-452-27414-1., ISBN13: 9780452274143. This book is a seminal work on endocrine disruptors (chemical contaminants having impact at extremely low levels in the environment).
Recommended by Daniel Friedman, this book is a critical update to the landmark Silent Spring by Rachel Carson and discusses the effects of minute trace amounts of chemical contaminants in the environment. The text "Identifies the various ways in which chemical pollutants in the environment are disrupting human reproductive patterns and causing such problems as birth defects, sexual abnormalities, and reproductive failure. Reprint. Tour. NYT."
Amazon.com Review: By O T (Ontario, BC) - 'Our Stolen Future' is a great introduction to one of the most important scientific discoveries in our time. Having recently completed a thesis project at university on Endocrine Disruptors, I have reviewed hundreds of papers on the subject. This book is a good clear overview of the scientific literature on EDs. The authors are experts - Theo Colborn is largely responsible for creating the field by bringing together diverse researchers so they could see the big picture of their work. Many of the principle investigators are interviewed and quoted at length on the way chemicals participate in and interfere with delicate hormonal systems in animals (including humans). The major accomplishment of the book is to make an easy-to-follow story out of complex research. Many resources are available to help you assess the reliability of this story, and the best thing to do if you have any doubts is read review articles in scientific journals (which are easier to understand than technical papers). The Physicians for Social Responsibility (PSR) have a guidebook for health-care professionals on Endocrine Disruptors, and the US EPA has many reports on the matter. Beware of people or websites who try to 'debunk' this book (or the science behind it) by simply declaring it false, flawed or disproven. There is far too much supporting research for so simple a refutation.
OPINION: Significant and discussed in this book is the observation that at certain critical points in the development of animals, presumably including humans, exposure to extremely low levels of endocrine disruptor chemicals (EDC's) (such as BPA - Bisphenol-A or BPA, Diethylstilbestrol - DES, dioxins, PCBs, and chemicals used in the production of certain cleansers, dyes, flame retardants, plastics, pesticides, white papers ) perhaps just a few molecules, or in the parts per trillion, is sufficient to cause disruption of the animal's development, including proper sex differentiation, or the lack of it that produced androgynous ducks unable to reproduce under such conditions.
A endocrine disruptor is a synthetic chemical compound that mimics natural hormones when it is taken into the body of a human or other animal. It "disrupts" the endocrine system by turning on or off normal chemical signals that in turn can affect normal hormone levels, bodily functions, and significantly, the development of embryos. Further, unlike naturally occurring hormones ingested, for example from plants (phytoestrogens), synthetically-generated hormones accumulate in the body and can have a half-life of decades or longer.
One significance of this finding includes the observation that an important medical effect that occurs with exposure to chemicals in extremely low concentrations means that experiments to test for correlations between chemical exposure and subsequent serious medical problems will be deeply flawed if, for example, the experimental design does not include testing for the presence of the chemical at extremely low levels. A related concern is that even if harmful effects from exposure to extremely low concentrations of an endocrine disruptor are occurring, teasing out and proving that relationship can be also extremely difficult.
Silent Spring, Rachael Carson, Mariner Books; Anv edition (October 22, 2002), ISBN-13: 978-061824906.
Amazon.com Review:
Silent Spring, released in 1962, offered the first shattering look at widespread ecological degradation and touched off an environmental awareness that still exists. Rachel Carson's book focused on the poisons from insecticides, weed killers, and other common products as well as the use of sprays in agriculture, a practice that led to dangerous chemicals to the food source. Carson argued that those chemicals were more dangerous than radiation and that for the first time in history, humans were exposed to chemicals that stayed in their systems from birth to death. Presented with thorough documentation, the book opened more than a few eyes about the dangers of the modern world and stands today as a landmark work.
Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
When Technology Fails, Matthew Stein, Chelsea Green Publisher, 2008,493 pages. ISBN-10: 1933392452 ISBN-13: 978-1933392455, "... how to find and sterilize water in the face of utility failure, as well as practical information for dealing with water-quality issues even when the public tap water is still flowing". Mr. Stein's website is www.whentechfails.com/
In addition to citations & references found in this article, see the research citations given at the end of the related articles found at our suggested
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: info@carsondunlop.com. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
Carson Dunlop Associates provides extensive home inspection education and report writing material. In gratitude we provide links to tsome Carson Dunlop Associates products and services.