Water Quality: Testing, Filters for, and Purification of Drinking, Ground and Pool Water » Disinfection Byproducts

What is the Difference Between Total Residual Chlorine and Free Chlorine?

Water Testing Blog — Thu, 26 Apr 2012 18:36:08 +0000

Simply put, the total chlorine concentration in a water sample includes all available free chlorine plus all the chlorine that has already oxidized (acted on) contaminants in the water and become combined chlorine (monochloramines).

Easy-to-Use WaterWorks 2
Free & Total Chlorine Test Strip

Free (available) chlorine refers to the concentration of chlorine molecules residing a water sample that have not, yet, oxidized contaminants. As a general rule you want to maintain a free chlorine residual in a body of water or water source.

Therefore, if a water sample has a total chlorine residual but no free, available chlorine, then the sample may or may not be ‘safe’. Some public (municipal) drinking water systems use only combined chlorine

Why would they do that?

It seems counter-intuitive that a public water systems would choose combined chlorine over free chlorine given free chlorine’s superior disinfecting (oxidizing) properties, but monochloramines do still have oxidizing capabilities and they do not create compounds (disinfection by-products, tri-halomethames, TTHM’s, etc.) that may cause cancer.

Pool Check 5-Way

So… if you want to know how much free chlorine you have versus how much combined chlorine you have, simply subtract the free chlorine concentration from the total chlorine concentration:

(Total Chlorine) – (Free Chlorine) = Combined Chlorine

For pool water you can use a test strip like the Pool Check 5-Way or a Basic Taylor Test Kit to determine the free and total chlorine concentrations of a sample.

For drinking water you can use test strips like SenSafe Free Chlorine Water Check to determine the free chlorine concentration of a water sample and SenSafe Total Chlorine Water Check to determine the total chlorine concentration of a water sample.

OR, for an even easier test procedure, you can use the WaterWorks 2 Free & Total Chlorine Test Strip which tests for both free and total chlorine at the same time.

SenSafe Free Chlorine Test

SenSafe Total Chlorine Test

Free Chlorine High Range Test

NSF/ANSI Standard 53 for VOC Reduction

Water Testing Blog — Thu, 21 Jul 2011 13:03:14 +0000

First off, we’d like to thank each and every one of you that pointed out a glaring omission in our last posting: We failed to list the VOC’s (volatile organic compounds) that water treatment systems bearing NSF/ANSI Standard 53 Certification reduce and/or remove.

So, without further ado, get ready for a list of chemicals and chemical compounds that call into the VOC category of NSF/ANSI Standard 53:

alachlor	endrin	simazine
atrazine	ethylbenzene	styrene
benzene	ethylene dibromide (EDB)	1,1,2,2-tetrachloroethane
carbofuran	haloacetonitriles	tetrachloroethylene
carbon tetrachloride	bromochloroacetonitrile	toluene
chlorobenzene	dibromoacetonitrile	2,4,5-TP(silvex)
chloropicrin	dichloroacetonitrile	tribromoacetic acid
2,4-D	trichloroacetonitrile	1,2,4-trichlorobenzene
dibromochloropropane (DBCP)	haloketones	1,1,1-trichloroethane
o-dichlorobenzene	1,1-dichloro-2-propanone	1,1,2-trichloroethane
p-dichlorobenzene	1,1,1-trichloro-2-propanone	trichloroethylene
1,2-dichloroethane	heptachlor	trihalomethanes (TTHM)
1,1-dichloroethylene	heptachlor epoxide	(THM) bromodichloromethane
cis-1,2-dichloroethylene	hexachlorobutadiene	bromoform
trans-1,2-dichloroethylene	hexachlorocyclopentadiene	chlorodibromomethane
1,2-dichloropropane	lindane	chloroform
cis-1,3-dichloropropylene	methoxychlor	xylenes
dinoseb	pentachlorophenol

Note: While the NSF/ANSI Standard 53 for VOC Reduction deos specify just 43 compounds, the list above contains extra entries because the Standard considers three ‘families’ of compounds single entries and then goes on to specifically call out the names of individual compounds within those chemical families.

Where do these things called VOC’s come from?

The VOC Fairy brings them while you sleep… but not really. On the NSF Web Site we found the following definition which we think does an excellent job of describing the origin of VOC’s:

“The category of VOC (Volatile Organic Chemical) includes a number of chemicals that are both man-made and naturally occurring. Water from wells and utilities may contain some of these contaminants. Some VOCs are pesticides, herbicides, or insecticides that seep into the ground water after application. Other VOCs enter the water supply through industrial or other waste disposal. This category also includes total trihalomethanes, which are a by-product of chlorination.”

For those who believe VOC’s cannot get into their water supply because you don’t live in close proximity to industrial complexes or agricultural areas, think again. Once these things enter the environment they, like many other categories of drinking water contaminants, could possibly travel many miles before dissipating to a ‘safe’ level.

Thanks for the chemistry lesson, but…

“Why does any of that matter to me?”

In a nutshell, scientists and health officials have agreed that the presence of any of those chemicals in too high a concentration in water poses a potentially serious health risk to people if they consume the water. Devices that have tested and certified to NSF/ANSI Standard 53 for the reduction of VOC’s must satisfactorily reduce levels of all the chemicals on that list to ‘safe’ levels.

Inline Refrigerator/Icemaker Water Filter
Tested & Certified to NSF/ANSI Standard 53
for VOC Reduction in Drinking Water

Under Sink Water Filter
Tested & Certified to NSF/ANSI Standard 53
for VOC Reduction in Drinking Water

Filter to Remove Chloramines

Water Testing Blog — Fri, 13 May 2011 01:50:57 +0000

Not a fan of chloramines in your drinking water? You now have a means of removing those pesky chloramines!

Chloramines? What are chloramines? Take a look at this earlier Water Testing Blog entry on Free Chlorine, Combined Chlorine and Total Chlorine and get a quick education on the topic!

Whether created as a byproduct of disinfection via free chlorine or the intended disinfectant in a water system, most people do NOT like the taste and odor of chloramines in their water.

Thankfully Pentek has come out with a product called the Pentek ChlorPlus 10 Chloramine Removal Water Filter Cartridge that fits in standard 10″ (x 2.5″) filter housings used in filter sytems produced by companies such as Pentek (obviously!), US Filter (recently acquired by Pentek!), Cuno, Filterite, Keystone, US Water, Water Resurces, Harmsco, and many other popular brands of water filtration systems. If your system uses a standard 10″ x 2.5″ housing, the Pentek ChlorPlus 10 ought to fit just fine!

Having said that last bit, please check the dimensions of your current filter and/or housing before ordering this product!

Looking for a 10″ replacement filter with NSF Certification? The Pentek ChlorPlus 10 uses a component tested certified to NSF Standard 42.

What does the Pentek ChlorPlus 10 remove/reduce? Using 1 micron carbon block technology this product (255416-43) should seriously reduce chloramine concentrations in drinking water and in doing so remove the (offensive) taste and odor associated with chlorine while also helping to pull out unwanted sediment, if present.

Free & Total Chlorine Test

DPD-1: Free Chlorine Testing

Chlorine Testing Meter

Removing/Reducing Trihalomethanes in Drinking Water

Water Testing Blog — Fri, 28 Jan 2011 13:03:37 +0000

As the debate over the benefits and problems associated with use of free chlorine ( EPA Approved test strip for free chlorine ) as a disinfectant in public and private drinking water systems rages on and more people become aware of compounds known as disinfection byproducts, the desire for point-of-use water filtration systems capable of removing disinfection byproducts continues to grow.

PUR FM-5050B Faucet Filter w/ Flavor Options
Tested & Certified to NSF/ANSI Standards 42 and 53

One particular disinfection byproduct of, trihalomethanes (often abbreviated as THM’s or TTHM’s), has gained enough notoriety that companies like PUR have started certifying some of their products to NSF/ANSI Standards for the reduction of trihalomethanes in drinking water.

Below you will find a list of several PUR water filtration products that have tested and certified to NSF/ANSI Standard 53 (Drinking Water Treatment Units – Health Effects) for the reduction of TTHM’s and other unwanted drinking water contaminants:

For those unfamiliar with how trihalomethanes get into drinking water, they get created when free chlorine molecules attack, neutralize and become entangled with a biological contaminant. That process chain of events converts free chlorine into combined chlorine and in the process disinfection byproducts get created.

What harm can trihalomethanes in drinking water cause?

Four different trihalomethanes can form as a result of chlorination: Chloroform, Bromodichloromethane, Dibromochloromethane, and Bromoform. The United States Environmental Protection has found that excessive exposure to these compounds has resulted laboratory rats developing cancer.

While many scientists may disagree on the exactly how much exposure to each compound constitutes overexposure, we think it wise to keep tabs on your local water treatment system’s track record of trihalomethane level management (data available in annual reports) and if deemed necessary, install an NSF certified water treatment system capable of reducing trhalomethane levels.

Urine, Sweat, Skin and Cosmetics in Pool Water May Cause Cell Damage

Water Testing Blog — Tue, 27 Jul 2010 23:50:04 +0000

Taking a leak in the swimming pool… now shown to potentially cause harmful cell damage. As if the whole ‘Ewwwww! GROSS!!!’ factor shouldn’t have ALREADY given people incentive not to do it, right?

Well we all know how lazy OTHER people… ahem… can be.

Public swimming pools are more dangerous than you might think, a new study suggests. When sweat and urine, among other organics, mix with the disinfectants in pool water, the result can be hazardous to health.

The findings, announced this week, link the application of disinfectants in recreational pools to genetic cell damage that has been shown to be linked with adverse health outcomes such as asthma and bladder cancer.

Pool water represents extreme cases of disinfection that differ from the disinfection of drinking water as pools are continuously exposed to disinfectants. But with so many people cooling off and exercising in pools and water parks (339 million visits across the United States each year), the disinfectants are a must to prevent outbreaks of infectious disease.

Chlorine and Pee Don’t Mix

The problem occurs when the sanitizers mix with organic matter.

“All sources of water possess organic matter that comes from decaying leaves, microbes and other dead life forms,” said study researcher Michael Plewa, University of Illinois professor of genetics. “In addition to organic matter and disinfectants, pool waters contain sweat, hair, skin, urine and consumer products such as cosmetics and sunscreens from swimmers.”

These consumer products are often nitrogen-rich, and when mixed with disinfectants, these products may become chemically modified and converted into more toxic agents.

Long-term exposure to these disinfection byproducts can mutate genes, induce birth defects, accelerate the aging process, cause respiratory ailments, and even induce cancer, according to the researchers. While the new study did not examine actual effects on humans, it suggests such research might be warranted. ( source )

So listen up, all you nasty bastards and batardettes out there who find it too burdensome to cart your fun -in-the-sun frolicking butts to the bathroom: STOP PEEING IN THE POOL!

Oh, and for all of you who think, “It’s my pee, so it won’t hurt me,” all the other pee rule violators think the exact same thing.

Other Articles of Interest

Question: Is Well Water Better Than City (Tap) Water?

Water Testing Blog — Mon, 15 Mar 2010 13:03:04 +0000

We recently received an email from Emma in North Carolina and she wrote,

We’re building a new house right on the edge of where the local water plant stops delivering water and want to know if we will be better off hooking up to the water line or having well put in. Some people say we’re lucky to have a choice, but really it’s just one more decision we have to make and we already have so many! Can you help? Thanks!

Emma

As Emma implied, sometimes having a choice makes for a lot more work – if you choose to research the options properly.

Hooking up to city water offers the security of knowing that the city has to test its water routinely before distribution and must inform you if it has experienced any ‘incidents’ which may put you in danger. On the flip-side, though, you will receive a bill each month to cover the expense of testing, monitoring, filtering and purifying the water going into your new home.

Investing in a well for your new home will rid you of that pesky water bill each month, but it will also make you 100% responsible for the quality and safety of water it produces once it passes an initial test done by the well drilling company.

We honestly do not have an answer, Emma, because some well water comes up cleaner and more pure than any water company could ever distribute… and other well water comes up nastier than backwoods swamp water and/or containing potentially dangerous chemical compounds whose origin even the best scientists in the World have trouble locating.

Pretty much all city water contains some form of disinfectant which can create unpleasant tastes and odors in drinking water. It can also irritate skin, bleach clothing, etc. and some water systems contain obnoxious (and smelly) levels of chlorine which can make water taste absolutely wretched.

While on the topic of chlorine, the most widely used disinfectant for public water systems, produces trihalomethanes (THM’s), a potentially carcinogenic disinfection byproduct, when chlorine molecules attack organic contaminants in water.

Getting back to the well water, commonly occurring events in the environment can change the quality of well water on a daily basis. Heavy rains, a lack of rain, temperature and even air pressure can radically alter the nature of water pulled from well – and let us not forget about pollution from industry which can seep into the ground 100’s of miles away from a well and still, somehow, make its way into that water that well produces at some point.

So, Emma, in the end, and if you want to make the best possible decision regarding where you will get your drinking water, we suggest you have a sample of water drawn from the aquifer your proposed well will access and have it tested by a certified water testing laboratory such as National Testing Laboratories. Contact the well drilling company you think you may use to drill, if you go that route, and ask them for advice on getting sampling and testing done. Do make sure they submit the sample to a certified water lab, though, and not do the testing themselves!

Then contact the local water company and ask for a copy of their latest water quality report, usually referred to as a Consumer Confidence Report and abbreviated as CCR.

With both reports in hand, weigh the pros and cons of each and remember that no matter which option you choose, you may STILL want to consider having a Whole House Water Filter System installed and/or purchasing point-of-use water filter devices for the shower, faucet and countertop.

Question: What is EPA Limit for Trihalomethanes in Drinking Water?

Water Testing Blog — Fri, 06 Nov 2009 14:51:39 +0000

We’d like to thank “Trinity” for asking the following question about trihalomethane levels in drinking water:

“In school we recently learned that chlorine added to drinking water by water treatment facilities reacts with organic contaminants in the water and forms harmful compounds called trihalomethanes. Does the EPA have a guidleine which limits the amount of trihalomethanes are considered safe?” — Trinity in Washington

First of all, we want to clarify something in Trinity’s question: Not all forms of chlorine added by water treatment facilities will cause trihalomethanes to form. Adding ‘free chlorine’ to water containing organinc contaminants will result in the formation of thrihalomethanes while adding ‘combined chlorine’, also referred to as chloramines, to water containing organic contaminants will not.

Unsure of the difference between free chlorine and total chlorine? The following Water Testing Blog postings will help:

Getting back to Trinity’s question, though, prior to 2004 the EPA set the maximum contaminant level (MCL) for trihalomethanes in drinking water at 100 parts per billion (ppb). In 2004 the EPA lowered the MCl for trihalomethanes in drinking water to 80 ppb. ( source )

SenSafe Free Chlorine
Water Check

WaterWorks 2 Free & Total Chlorine Test Strips

SenSafe Total Chlorine
Water Check

THM’s May Affect Pregnant Women and Their Unborn Children

Water Testing Blog — Tue, 07 Apr 2009 17:10:30 +0000

Not many people actually enjoy the taste or smell of chlorinated drinking water, but did you know that recent studies have unofficially linked birth defects to chlorinated drinking water? It seems as though a pregnant woman’s exposure to chlorine byproducts called trihalomethanes (THMs) in drinking water, bath water, etc. may play a part in causing serious health problems for her unborn child:

“Expectant mothers can expose themselves to the higher risk by drinking the water, swimming in chlorinated water, taking a bath or shower, or even by standing close to a boiling kettle, say researchers.

The finding, based on an analysis of nearly 400,000 infants, is the first that links by-products of water chlorination – chemicals known as trihalomethanes, or THMs – to three specific birth defects.

Exposure to high levels of THMs substantially increased the risk of holes in the heart, cleft palate and anencephalus, which results in the absence of a major portion of the brain, skull, and scalp.” ( source )

Most water systems chlorinate the water they provide in an effort to eliminate parasites and bacteria in drinking water which could lead to waterborne ailments and illnesses.

Not sure if your water contains THMs? Maybe the next few statements will help:

Public water supplies that use free chlorine as their primary disinfectant (instead of chloramines) may contain THMs. The compounds form when free chlorine molecules lock horns with a biological contaminant during the disinfection process.
Public water supplies that use chloramines as their primary disinfectant (instead of free chlorine) typically do not contain THMs. However it should be noted that these water systems do periodically ‘burn’ their water lines with free chlorine in an effort to get rid of any biofilm that has formed and THMs do result from those ‘burn’ sessions.

Still unsure as to whether or not your drinking water may contain THMs? You have three options:

Call your local water authority and ask them if they use free chlorine as the primary disinfectant or chloramines. If so, then your water most likely contains chloramines.
Have your water tested by a certified water testing professional.
Use reliable drinking water test kits for both free chlorine AND total chlorine.

Acceptable TDS Meter Readings Do Not Guarantee Safe Drinking Water

Water Testing Blog — Thu, 26 Mar 2009 17:07:59 +0000

In a recent article by Andrew Zeigler in Water Conditioning & Purification Magazine, we found the following statement intended for dealers of drinking water treatment systems which we certainly do agree with:

“Stop using the TDS (total dissolved solids) meter as the only measurement of water quality. Disinfection Byproducts like Trihalomethanes, Volatile Organic Compounds, METHYL tertiary-butyl ether, chlorine, chloramines, cysts and lead are the primary contaminants to Public Water Systems. They have no impact on the conductivity of the water. Yet these do not register on a TDS meter. And public water systems primarily supply from surface water that tends to have low TDS levels.” ( Water Conditioning & Purification Magazine, March 2009, page 42 )

While TDS does play a large part in the determining whether or not your water will leave deposits on your fixtures, it alone does not indicate the relative safety and purity of your water. As always Water Testing Blog suggests that people get their water tested by Certified Water Analysis Laboratories if they suspect a serious health risk.

For all other water testing needs, simple at home drinking water test kits used in conjunction with TDS meters ought to work just fine. you can find more information about home drinking water test kits on this page. You can also find more information about home drinking water test kits by using the links below:

Arsenic in Water and Soil: Arsenic Quick^TM

Bacteria in Water: Bacteria Check

Chlorine Residual (Free): SenSafe^TM Free Chlorine Water Check

Chlorine Residual (Total): SenSafe^TM Total Chlorine Water Check

Lead in Water: Lead in Water Test Kit

Multi Parameter (6 Parameters): Well Water Check

Multi Parameter (11 Parameters): Well Driller Standard Water Test Kit

Multi Parameter (13 Parameters): COMPLETE Water Test Kit

Multi Parameter (15 Parameters): Water Quality Test Kit

Tests Find Bottled Water No Cleaner Than Tap Water

Water Testing Blog — Wed, 19 Nov 2008 21:53:55 +0000

What happened to the days when you could TRUST a company not to misrepresent a product they touted as ‘pure’?

Our opinion: Those days died with the dinosaurs or they never really existed!

Looking for ways to cut back in these tough economic times? An environmental group suggests skipping the bottled water and drinking from the tap. It might even be healthier.

The Environmental Working Group says its tests how 10 popular U.S. bottled water brands contain mixtures of 38 different pollutants, including bacteria, fertilizer, Tylenol and industrial chemicals, some at levels no better than tap water.

Wal-Mart’s Sam’s Choice at several locations contained contaminants exceeding California’s bottled water quality standards and safety levels for carcinogens under the state’s Safe Drinking Water and Toxic Enforcement Act, according to the group’s laboratory tests. Giant Foods’ Acadia brand consistently retained the high levels of cancer-causing chlorination byproducts found in the suburban Washington DC tap water from which it is made.

Overall, the group says the test results strongly indicate that the purity of bottled water cannot be trusted.

“It’s buyer beware with bottle water,” said Jane Houlihan, Vice President for Research at EWG. “The bottled water industry promotes its products as pure and healthy, but our tests show that pollutants in some popular brands match the levels found in some of the nation’s most polluted big city tap water systems. Consumers can’t trust that what’s in the bottle is anything more than processed, pricey tap water.”

“For years the bottled water industry has marketed their product with the message that it is somehow safer or purer than tap water,” said Wenonah Hauter, executive director of the non-profit consumer advocacy group Food & Water Watch. “This new report provides even more evidence that the purity of bottled water is nothing more than a myth propagated to trick consumers into paying thousands times more for a product than what it is actually worth.”

EWG said that laboratory tests it commissioned at one of the country’s leading water quality laboratories found 38 contaminants in ten brands of bottled water purchased from grocery stores and other retailers in nine states and the District of Columbia.

The pollutants identified include common urban wastewater pollutants like caffeine and pharmaceuticals, an array of cancer-causing byproducts from municipal tap water chlorination, heavy metals and minerals including arsenic and radioactive isotopes, fertilizer residue and a broad range of industrial chemicals. Four brands were also contaminated with bacteria.

Unlike tap water, where consumers are provided with test results every year, the bottled water industry does not disclose the results of any contaminant testing that it conducts, EWG said.

Americans paid $12 billion to drink 9 billion gallons of bottled water last year alone, EWG said. Yet, the tests show several bottled waters bore the chemical signature of standard municipal water treatment–a cocktail of fluoride, chlorine and other disinfectants whose proportions vary only slightly from plant to plant. In other words, some bottled water was chemically almost indistinguishable from tap water.

The only striking difference, the group says, is the price tag. The typical cost of a gallon of bottled water is $3.79–1,900 times the cost of a gallon of public tap water. (source article)

So what can YOU do to help make sure the water you consume does not contain harmful chemicals? Simple: Learn everything you can about the source your water comes from. If it comes from a bottle, read the bottle label and research the company that did the bottling. By law they must divulge the source of their water and you may find out that they merely take water from their own local (municipal) water supplier, run it through an activated carbon filter, bottle it, and ship it to you.

For those of you using well/spring water: click here for at-home drinking water testing options

For those of you on municipal water systems: click here for at-home drinking water testing options