This article describes the types of contaminants that may be found in wells or drinking water and suggests a strategic approach to reduce the chances that you order a costly test that simply doesn't check for a local water contaminant that may be or is present in the water source.
This article explains the general classes of water contaminants covered in a general water test.
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- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?
General Classes of Water Contaminants Found in Drinking Water or Water Wells
What drinking water contamination tests should you order?
This article outlines the general classes or groups of comprehensive water tests that one would consider when attempting to perform comprehensive water testing for a broad range of contaminants.
Categories of water contaminants by contaminant type: "Animal, mineral or vegetable" so to speak, include the twelve groups below. Some of these groups are overlapping, but I include them here as an easily-recognied digest of various government and private lists of water contaminants.
Questions to Ask Before Ordering Water Tests
Watch out: there is no single test that will reliably screen drinking water for all possible contaminants.
For that reason it makes sense to have a thougtful strategy for deciding what water potability or water contaminant tests you should order. Some help is available from
Your local water test lab: they know what contaminants are commonly found in wells near your property - ask for advice
The location of your property: where is it, what contamination sources are nearby, what sources are likely to drain onto your property or under it?
History of use of your property:
-
Was it an orchard or farm? What chemicals were used?
- Have buildings or the property been treated for pesticides?
- Are you in a flood zone? Has the well been submerged in floodwaters?
- Were there industrial processes conducted on the property or nearby? What chemicals or contamiants were used?
Ask your neighbors: neighbors who have drinking wells often will share your concern for safe drinking water and may know of older events that affect local wells but that are not widely publicized.
Inspect your property: a visual inspection, better by an expert, may spot telltale clues that suggest further investigation or tests of water or soil. Just walking properties I have found
- buried and other abandoned oil tanks and gas tanks
- evidence of amateur, incompetent application of toxic and long-enduring pesticides
- homeowner son disposing of used motor oil by dumping it into an old un-used drilled well (what an idiot!)
- old containers used to store toxic chemicals, sprays, pesticides, insecticides, etc.
History of toxic spilled close to your property: consult your country's inventory of toxic spills or releases. Look for ones that are close enough to your property to have affected it.
Watch out: national toxic spills or releases recorded by your country or municipality will not include smaller and un-reported toxic releases.
In the U.S. see the U.S. EPA Toxics Release Inventory (TRI) hosted at https://www.epa.gov/toxics-release-inventory-tri-program - this is a public database giving maps showing known toxic releases by county, city, state and zipcode.
This database of toxic spills covers nearly 22,000 companies, agencies, activities across the U.S. that handle large amounts of harmful or toxic chemicals. As I've warned that will NOT include smaller activities that may still be close at hand.
Excerpt from website: The Toxics Release Inventory (TRI) is a resource for learning about toxic chemical releases and pollution prevention activities reported by industrial and federal facilities. TRI data support informed decision-making by communities, government agencies, companies, and others. Section 313 of the Emergency Planning and Community Right-to-Know Act (EPCRA) created the TRI Program.
Below is an example of use of the US EPA TRI as of April 2019, searched by zip code 36752 - Burkville Alabama - area of a Sabic Plastics plant discussed by Tabuchi, Hiroko et als in Mixing Water and Poison, The New York Times, 2018/02/07 p. A13
[Click to enlarge any image]
Categories of water pollution contaminants by contaminant type
Bacterial contaminants, including coliform from sewage contaminants or other bacteriological water contaminants that occur in the water source or well
Bulk organic contaminants in water include hydrocarbons such as oil or grease*
Other biological contaminants (other than bacterial) such as fungal or viral contaminants, and including more obvious biological contaminant sources such as a dead animal in a well or fecal waste from spiders or other insects that may enter a well.
Chemical contaminants such as pesticides, herbicides, and in some cases contaminants that may be harmful though present only at very low levels, even below current permitted levels in drinking water, such
as ENDOCRINE DISRUPTERS at BUILDINGS. See Halogenated hydrocarbons polycyclic aromatic hydrocarbons listed separately in that article series.
Mercury contamination in water may be described under this chemical category or under that of metal contaminants.
Similarly, many sources include nitrogen compounds in water among chemical contaminants.
Halogenated Hydrocarbons or Persistent Organics, a group of chemicals that are very resistant to decay such as DDT and PCBs.* - U.S. EPA (2014)
Metal contaminants in water. The U.S. EPA cites metals such as iron, manganese, lead , cadmium, zinc, and mercury, and metalloids such as arsenic and selenium* - U.S. EPA (2014)
Nutrient contaminants in water, principally phosphorous nitrogen. The U.S. EPA notes ... nitrogen compounds such as ammonia. Elevated levels of phosphorous can promote the unwanted growth of algae. This can lead to the amount of oxygen in the water being lowered when the algae die and decay. High concentrations of ammonia can be toxic to benthic organisms.* - U.S. EPA (2014)
Physical contaminants in water, in a category intended to describe refuse (plastic bottles, cans, trash or large particles, may be listed as category separate from "solid contaminants" described below.
Polycyclic Aromatic Hydrocarbons (PAHs), a group of organic chemicals that includes several petroleum products and byproducts* - U.S. EPA (2014)
Radioactive contaminants in drinking water such as radon are properly listed under chemical pollutants or gaseous pollutants.
Solid contaminants in water such as sediment (soil, organic debris)
* The five asterisked contaminants in our longer list above are listed by the U.S. EPA as the "Five major types of pollutants are found in sediments" that might also be present in drinking water.
Types of Water Pollution in the U.K.
In the U.K., water-pollution.org.uk, a separate organization, lists the following more generalized types of water pollution. This list is helpful for understanding certain common properties held by various water pollutants.
But this list is a bit confusing too as it mixes areas where water is found (surface water vs ground water) with types of pollution (microbiological and nutrient pollution).
Groundwater water pollution
Microbiologial water pollution
Nutrient pollution in wagter
Surface water pollution
Suspended matter pollutants in water
Comprehensive tests for water pollutants
Watch out: a "water potability test" may sound like such testing tells you if water is completely safe to drink. But as the term "potability test" is commonly used, it refers only to a test for the presence or absence of coliform bacteria. While potability tests are inexpensive and are a very good way to start checking on the safety of drinking water, potability testing is no proof against other possible water contaminants including other forms of bacteria and various chemicals.
Comprehensive water testing covering the groups listed below may be appropriate when purchasing a new property, when
local environmental conditions are unknown but suspect, or when building occupants have unusual health vulnerability or compromised immune systems.
We advise also that you speak with the local health department and neighbors to ask if there are any
known specific issues or contaminants nearby, as we have by this means discovered very unusual local water contaminants which otherwise no one
would have thought to test.
Be sure to review actual parameters with your home inspector or laboratory:
parameters and costs vary.
Watch out: because the number of individual water contaminating substances is potentially very large, you risk both wasting money and falsely presuming that your drinking water is safe if you simply choose a "catchall" water test for contaminants. See Sampling Guidance for Unknown Contaminants in Drinking Water (cited below) for the U.S. EPA's comments on this problem.
Therefore we suggest as a general approach choosing water tests for unknown contaminants using a strategy that includes the steps listed below. To avoid an inefficient use of your water testing dollars, an approach that either raises questions for further investigation or closes off certain lines of investigation can be particularly helpful.
For example if the property was a farm you might test for fertilizers. If the property was previously an orchard you might test for certain pesticides used in those businesses.
Check with neighbors & local water test labs for known water problems in the area. We advise that you speak with the local health department and neighbors to ask if there are any
known specific issues or contaminants nearby, as we have by this means discovered very unusual local water contaminants which otherwise no one
would have thought to test.
Check property-specific visual clues: presence of fuel tanks, farm equipment, even trash that may include chemical or pesticide containers
Check property history: history of use of a property may disclose prior uses that involved potential pollutants for which you 'd test. At a strip mall we observed a pesticide storage trailer parked in the woods on the property. A test for pesticide spills came up negative. But a historical review showed a prior metal plating business on the site had contaminated both soils and a nearby stream with heavy metals.
Check the history and use of nearby properties whose surface or groundwater runoff may pass onto the property of interests.
Choose a comprehensive test for common contaminants.
Add special tests for special-suspected contaminants based on other property review steps.
Comprehensive water testing covering the groups listed below may be appropriate when purchasing a new property, when
local environmental conditions are unknown but suspect, or when building occupants have unusual health vulnerability or compromised immune systems.
Water is the universal solvent and it has the capabilities of dissolving just about anything. Because of this unique property water can easily become contaminated. Most common complaints are usually odor or staining problems; like those associated with sulfur and iron. However, serious contaminates as Lead and E.Coli Bacteria may be toxic affecting your family's health. This is why testing your water initially and annual monitoring is important.
COMPREHENSIVE INITIAL WATER TEST
Comprehensive Test would be expected to address four categories of testing in water:
1. Inorganic (this includes minerals and physical properties)
2. Organic (petroleum products, gasoline, fuel oils and solvents)
3. Microbiology (Coliform and other bacteria)
4. Radiological (radon gas)
This is a good way to start. The comprehensive Test is a powerful tool in detecting contaminates commonly found in surface and deep well waters. If there is a suspicion of Pesticides or Herbicides used near the water source it may be wise to include Pesticides and Herbicides analysis along with the Comprehensive Test.
ANNUAL MONITORING(Standard Test)
After the initial water test, it is customary to monitor the quality to make sure that no changes have occurred. Utilizing the Standard Test yearly is a good way to monitor the water source. If on the original water test, Organic compounds or high amounts of Radon Gas were found, we would strongly suggest again testing with the Comprehensive Test.
General vs Comprehensive water test parameters
GENERAL WATER TEST PARAMETERS lists a set of general water test parameters for property buyers or owners who want to be more thorough
than performing only a simple "coliform" or "bacteria" test (all that most banks require) but who do not have reason
to test for more specific water contaminants.
One might take this approach after obtaining
knowledge of property history, site inspection, conversation with neighbors, or check with a local health department.
This test is more thorough than a simple coliform test but may not meet VA or FHA minimum standards for drinking water.
Be sure to review actual parameters with your home inspector or laboratory:
parameters and costs vary.
COMPREHENSIVE WATER TEST lists the parameters in a more comprehensive water test for common contaminants.
Question: causes of cloudy water
(May 14, 2016) Jeff said:
I replaced my regulator,and added some air in tank,my regulator is a 20,40 but I'm having problems with dirty,cloudy looking water,was cleared up for couple weeks but now looking dirty again.what do I do,I don't think I have my regulator adjusted right for 1 thing another I might off blower to much air in tank,looks like a 25 gallon tank.can you help me?
Reply: air, debris, bacteria, minerals, bad water softener
Jeff:
The pressure regulator settings won't be the cause of dirty water in the system, though debris in the water supply can clog the sensor port on the pressure control switch and ultimately cause it to malfunction.
First do this simple test: from your kitchen sink, fill a clear water pitcher with water. If the water looks cloudy set the pitcher on the countertop and watch it for a few minutes. If the cloudiness begins to clear up, usually from the bottom of the pitcher and then moving towards the top, you are seeing fine air bubbles entrained in the water, not a chemical or mineral contaminant.
If the cloudiness does not dissipate there may be a mineral, bacterial, or other contaminant in the water supply or a bacterial contamination in the water pressure tank and piping or in the water heater tank.
Check the incoming water supply for debris; you may need to add a filter or treatment system; another cause of dirty water can be a change in the water table or damage to (and leaks into) the well casing.
If you suspect a water tank, you'll need to clean, drain, disinfiect, sanitize the tank. Search InspectApedia.com for SANITIZSE a WATER SOFTENER for a nice procedure. Also search for WELL SHOCK PROCEDURE.
References & Research on GeneralClasses of Contaminants Found in Drinking Water
ASSE, PROFESSIONAL QUALIFICATIONS STANDARD FOR INFECTION CONTROL RISK ASSESSMENT FOR ALL BUILDING SYSTEMS [PDF] ASSE 1079
Performance Requirements for Dielectric Pipe Unions (2012), ASSE International, 18927 Hickory Creek Drive, Suite 220,
Mokena, IL 60448 United States Tel:
(708) 995-3019 Website: https://www.asse-plumbing.org/ retrieved 2020/04/30 original source: https://asse-plumbing.org/media/23442/12000-2018.pdf
ASSE describes this document as "Free ASSE Series 12000 download - help prevent coronavirus exposure"
ASSE International is a membership organization and leading product and personnel certification agency for companies and individuals representing all disciplines of the plumbing and mechanical industries.
US EPA, "Five major types of pollutants are found in sediments" [now printed below], U.S. EPA, Major Contaminants, retrieved 5/11/2014, original souce: http://water.epa.gov/polwaste/sediments/cs/contaminants.cfm - dead link 2020/04/30, revised https://archive.epa.gov/water/archive/polwaste/web/html/contaminants.html
Quoting:
Five major types of pollutants are found in sediments:
Nutrients, including phosphorous and nitrogen compounds such as ammonia. Elevated levels of phosphorous can promote the unwanted growth of algae. This can lead to the amount of oxygen in the water being lowered when the algae die and decay. High concentrations of ammonia can be toxic to benthic organisms.
Bulk Organics, a class of hydrocarbons that includes oil and grease.
Halogenated Hydrocarbons or Persistent Organics, a group of chemicals that are very resistant to decay. DDT and PCBs are in this category.
Polycyclic Aromatic Hydrocarbons (PAHs), a group of organic chemicals that includes several petroleum products and byproducts.
Metals, such as iron, manganese, lead, cadmium, zinc, and mercury, and metalloids such as arsenic and selenium.
Metals, PAHs, and organics listed above can be toxic to various plants and animals, depending on the level of contamination. Some can also be toxic to humans depending on their levels. Many persistant organic contaminants and some metals biomagnify as they travel up the food chain.
Sources of Contaminants
The origins of sediment contamination can be divided into point and nonpoint sources of pollution. Point source pollution comes from a specific, identifiable source such as a pipe. Nonpoint source pollution cannot be traced to a specific spot.
Point sources include municipal sewage treatment plants, overflows from combined sanitary and storm sewers, stormwater discharges from municipal and industrial facilities, and waste discharges from industry.
Nonpoint sources include stormwater runoff from hazardous and solid-waste sites; runoff from croplands, livestock pens, mining and manufacturing operations, and storage sites. Atmospheric deposition is another source of nonpoint pollution.
US EPA, SAMPLING GUIDANCE FOR UNKNOWN CONTAMINANTS IN DRINKING WATER [PDF] (2017) U.S. EPA, Environmental Protection Agency, Office of Water (4601M)
1200 Pennsylvania Avenue, NW
Washington, DC 20460, EPA-817-R-08-003, retrived 5/11/2014, oreiginal source: http://water.epa.gov/infrastructure/watersecurity/wla/upload/ 2008_12_31_watersecurity_pubs_guide_watersecurity_samplingforunknown.pdf - dead link 2020/04/30 revised search results:https://www.epa.gov/waterlabnetwork/sampling-guidance-unknown-contaminants-drinking-water
US EPA, UNDERSTANDING THE SAFE DRINKING WATER ACT (SWD) (PDF), 1974-2004, U.S.
EPA 816-F-04-030, June 2004, revised search 2020/04/30 original source: https://www.epa.gov/sites/production/files/2015-04/documents/epa816f04030.pdf
U.S. EPA Toxics Release Inventory (TRI) hosted at https://www.epa.gov/toxics-release-inventory-tri-program - this is a public database giving maps showing known toxic releases by county, city, state and zipcode.
Excerpt:
The Toxics Release Inventory (TRI) is a resource for learning about toxic chemical releases and pollution prevention activities reported by industrial and federal facilities. TRI data support informed decision-making by communities, government agencies, companies, and others. Section 313 of the Emergency Planning and Community Right-to-Know Act (EPCRA) created the TRI Program. - 2020/04/30 op. cit.
This website describes the types of water testing available, outlines common water test fees,
describes the details of what parameters are included in various water test options, and gives
advice to assist you in deciding what tests to order.
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Citations & References
In addition to any citations in the article above, a full list is available on request.
[1] Drinking Water from Household Wells - PDF, U.S. EPA, Original source last retrieved 2/13/2013, original source: http://www.epa.gov/privatewells/pdfs/household_wells.pdf
1-Bromo-3-chloro-5,5-dimethylhydantoin (C5H6BrClN2O2) is produced world-wide and is also used in cleaners and bathroom disinfectants and deodorizers. Here is an example MSDS for this product, provided by Leisure Time
"Bacteria in Drinking Water" - "Chlorine," Karen Mancl, water quality specialist, Agricultural Engineering, Ohio State University Extension. Mancl explains factors affecting the effectiveness of chlorine in water as a means to destroy bacteria and other microorganisms. OSU reports as follows:
Chlorine kills bacteria, including disease-causing organisms and the nuisance organism, iron bacteria. However, low levels of chlorine, normally used to disinfect water, are not an effective treatment for giardia cysts. A chlorine level of over 10 mg/1 must be maintained for at least 30 minutes to kill giardia cysts. -- http://ohioline.osu.edu/b795/index.html is the front page of this bulletin
"Chemicals and Our Health", Nicholas D. Kristof, New York Times, 16 July 2009, p. 27. This outstanding editorial calls for improvements in public health policy to address phthalates and other environmental contaminants from common chemicals and products in everyday use. - DJ Friedman
Crystal Clear Supply provides portable ceramic water filter purifiers and portable reverse osmosis water treatment equipment - see http://www.crystalclearsupply.com/category_s/7.htm
Disinfectants in water: www.epa.gov/ogwdw/mdbp/pdf/alter/chapt_2.pdf provides an article on use of disinfectants for water treatment
"Drinking Water Safety in Emergencies", University of Minnesota extension, extension.umn.edu/info-u/nutrition/BJ646.html
Endocrine Disruptor Exchange, Dr. theo Colborn (also see Our Stolen Future). From that website: The Endocrine Disruption Exchange, Inc. is the only organization that focuses primarily on the human health and environmental problems caused by low-dose and/or ambient exposure to chemicals that interfere with development and function, called endocrine disruptors. ... TEDX's work focuses on the endocrine system, which is the exquisitely balanced system of glands and hormones that regulates such vital functions as body growth, response to stress, sexual development and behavior, production and utilization of insulin, rate of metabolism, intelligence and behavior. Hormones are chemicals such as insulin, thyroxin, estrogen, and testosterone that interact with specific target cells. The interactions occur through a number of mechanisms, the easiest of which to conceptualize is through a lock and key arrangement.
Giardia exposure limits for drinking water: see www.mass.gov/dep/water/drinking/standards/giardia.htm is the current regulatory exposure limit (your minimum target for
sterilization)
Health Effects of Chemical Contaminants in Drinking Water, US Environmental Protection Agency,
Hydrogen peroxide: Wikipedia on history of use of hydrogen peroxide: Information on Hydrogen peroxide as a sterilant is in Wikipedia at en.wikipedia.org/wiki/Sterilization_(microbiology) HO2 has been
used for a long time, including by vaporization for sterilizing freeze dryers.
Hydrogen Peroxide warning: US FDA Warning about drinking hydrogen peroxide: www.truthorfiction.com/rumors/h/hydrogen-peroxide.htm This article cites a 2003 entry in Journal
of Food and Science on using Hy.Perox to sterilize vegetables, referring to E.coli - NOT to Giardia.
Iodine: "Do Iodine Water Purification Tablets Provide an Effective Barrier against Cryptosporidium parvum?", Starke, Jeffrey A., Bowman, Dwight D., Labare, Michael, Fogarty, Elizabeth A., and others, Military Medicine, 25 October 2001 [possibly a later version of this article appeared in 2005 -DF] http://www.amsus.org/military medicine/milmed.htm
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.
US EPA: list of drinking water contaminants: see http://www.epa.gov/safewater/contaminants/index.html
UV light: This patent application for UV light sterilization www.patentstorm.us/patents/6565803.html Lists good references on water
purification for Giardia et als
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.