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:

• Free Chlorine, Combined Chlorine, Total Chlorine
• Free, Combined and Total Chlorine Re-Visited
• Testing Chlorine Levels — Drinking Water vs. Pool Water

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 )

In so far as we have read, no cases of Swine Flu have resulted from contaminated drinking water… so why the need for an article about Swine Flu on the Water Testing Blog?

Simple: Viruses like influenza can spread when one person sneezes and coughs their nasal discharge and/or saliva (gross!) lands on a surface that other people touch. The germs will then travel to whatever surfaces those people touch… including their own food, eyes, mouth, etc.

Proper use of sanitizing and disinfecting solutions on a regular basis helps to reduce the number of germs hanging out on surfaces and thus reduces the likelihood of people unknowingly picking up germs and accidentally infecting themselves or others with an illness.

Is chlorine bleach an effective sanitizer/disinfectant?

In most cases, yes. Chlorine bleach works quite well as a germ-killing agent on surfaces and as a matter of fact, many states require childcare facilities to use dilute bleach solutions to clean changing table surfaces and other areas where human waste, a known haven for harmful germs and bacteria, may (inadvertantly) come into contact with surfaces.

As an example, North Carolina requires childcare workers to wipe down a changing area with a disinfecting bleach solution containing between 500 and 800 parts per million free chlorine after they change each child’s diaper. How do they verify that they have the proper concentration of free chlorine in their disinfecting bleach solution? They test with a product such as the Free Chlorine Water Check Ultra High II test strip.

Perhaps ahead of its time, North Carolina REQUIRES childcare facilities to test the free chlorine levels eachtime thet make new batches of disinfecting solutions (for wiping down bathrooms, changing areas) AND sanitizing solutions (for wiping down tables, chairs, doorknobs, toys, etc.). Making sure each solution contains the proper free chlorine levels before use goes a long way to help prevent the spread of germs, bacteria and illnesses.

Sanitizing: 50 – 200ppm Free Chlorine | Disinfecting: 500 – 800ppm Free Chlorine

So what have we learned? Testing the free chlorine levels in cleaning solutions helps to ensure that cleaning efforts accomplish the goal of properly sanitizing and disinfecting surfaces where children and adults can easily pick up germs capable of infecting someone with the common cold, the ‘traditional’ flu, or worse yet, a case of Swine Flu.

Keeping the facilities clean during the flu season is also a consideration, both Shafer and Baeuchle said.

“We regularly sanitize all the toys. After a child has a toy in their mouth, it has to be sanitized,” Shafer said. “We sanitize the tables and chairs on a regular basis in the classrooms.”

Baeuchle said she is asking the school custodians to pay special attention to high frequency areas like water fountains and doorknobs. ( source

Interested in testing the concentration of chlorine bleach sanitizing and disinfecting solutions? You can pick up a Childcare/Daycare Kit which includes (3) bottles of North Carolina Licensed Child Care Association approved test strips, quarter cup and tablespoon measuring devices (for proper on-site metering of the bleach), and a copy of the procedures North Carolina wants child care workers to follow when mixing their sanitizing and disinfection solutions.

Several years ago researchers (we don’t recall from where) announced similar findings. Their research focused more on chloramine gas, a product of the reaction between free chlorine and organic contaminants such as sweat, body oils, etc. Additionally, the previous research also focused more on indoor pools where the chloramine gas could more easily build up as a result of poor ventilation.

The results of this more recent study, which broadened its focus to include children who swam in outdoor pools, indicate that children exposed to chlorinated pool water stand a much greater chance of developing allergies and asthma than children who swam in pools using alternate sanitizers such as silver/copper ionizers, which use far less chlorine.

MONDAY, Sept. 14 (HealthDay News) — Swimming in pools disinfected with chlorine may increase the odds that a child will develop asthma or allergies, new research suggests.

The study found that teenagers who spent more than 1,000 hours swimming in chlorinated pools, either indoors or outdoors, had more than eight times the risk of having asthma than did teens who primarily swam in pools using a copper-silver disinfecting method.

“Chlorinated pool attendance has a very significant impact on the prevalence of allergic diseases in the studied population,” said lead author Alfred Bernard, a professor of toxicology and research director at Catholic University of Louvain in Brussels, Belgium. ( source )

Does this mean all pool owners with chlorinated ought to run out into their backyards, drain their pools, and/or toss in a few pounds of chlorine neutralizer? ABSOLUTELY NOT!

Thus far the evidence indicates that proper usage of chlorine as a pool water disinfectant remains safe. The problems start, it seems, when chlorine levels get ‘too high’ in the water and when chlorine gases build up in the air above and around swimming pools.

“When used properly, [chlorine] is an efficient and safe disinfectant for swimming pools. However, when too much chlorine is added to water or builds up in the air of indoor pools, there is unavoidably some irritation of the organs of the bather in contact with the water and air,” he explained. “There is now increasing evidence that these irritating effects may be detrimental to the airways of regular swimmers, especially the children who are the most vulnerable and the most frequent attendees of chlorinated pools.” ( source )

So what can the average pool owner do to minimize the risks presented by their chlorinated pool? Simple: Test chlorine levels, and other vital water parameters, often and make sure not to use more chlorine than necessary to keep the water properly disinfected.

Bernard said that if you have a backyard pool, you should use as little chlorine as you can to safely disinfect the pool. He said that many people over chlorinate their pools to get clear blue water. But, he said, “chlorine is a disinfectant, not a cleaning agent.” ( source )

Indoor pool owners need to follow the preceding advice AND make sure their pool enclosure area has proper ventilation. Water in indoor pools typically has a higher temperature and thus tends to evaporate and also give off chlorine gas at a faster rate than cooler water.

“How can I test the chlorine level in my swimming pool?”

Swiiming pool test kits come in three basic forms, for the most part: Liquid Test Kits, Test Strips, and Pool Testing Meters.

After reading this article you may find yourself thinking, “I will switch to a copper-silver ionizer and say ‘goodbye’ to chlorine forever!” Sorry, but that last part will most likely not happen.

Many copper-silver ionizer pool water systems suggest maintaining low residual levels of free chlorine in pool water. Often times the suggested free chlorine levels will fall below the detection level of most test strips, liquid test kits and even some meters.

To monitor such low levels of free chlorine in pool water we suggest the Pool Check Low Chlorine 3-in-1 Test Strip which can detect free chlorine levels as low as 0.05 ppm.

With temperatures soaring to record and near record highs all across the United States, it comes as no surprise to us that we have received numerous questions pertaining to the proper treatment of green swimming pool water, smelly swimming pool water… and some water that would make the average sewer worker vomit.

Therefore we have located yet another online source for Pool Water Testing and Pool Chemical Supplies. Below you will find quick links to various pool testing supplies, pool chemicals, pool shock treatments and other items such as automatic chemical feeders for swimming pools.

Just as with your drinking water, though, nothing beats a professional water test if you have reason to suspect that harmful bacteria or harmful levels of contaminants have entered your pool water.

As a result of a massive influx of questions related to pool & spa water testing, we have decided to branch off our normal topic of drinking water quality testing and post a few things related to testing pool & spa water. Why? Simple: Some people have not yet made the connection that bad tap or ground water stays bad whether you drink it or fill your swimming pool with it.

For most people opening their swimming pool means raising the water level off with fresh, untreated water from a garden hose or in some cases, a delivery truck. Once full of water, the testing can begin.

How Should Pool & Spa Owners Test Their Water?

Excellent question! In the ‘old’ days most pool and spa owners had a simple two-sided test kit for chlorine/ bromine and pH which looked like this:

… and each year the owners of these pool water and spa water owners made a pilgrimage to their local pool store to acquire replacement reagents for their pool and/or spa water test kits which looked like this:

While at their local pool store picking up the replacement reagents for their pool/spa water test kits, pool and spa owners would usually submit a sample of water from their freshly filled pool or spa to a smiling person behind the counter at the ‘water testing station’. Within minutes of handing over a soda can, mason jar, yogurt container or other (hopefully) sealed container full of water the same smiling water station attendant would return with a sheet of paper telling them the free chlorine, total chlorine, ph, alkalinity, total (or calcium) hardness, cyanuric acid, total dissolved solids, copper and iron levels in their water.

Can’t Pool & Spa Owners Test Their Own Water?

Of course they can. Swimming pool and spa water test kits

Then came the fun part: Picking up and paying for all the various tubs and canisters of powders and liquids that would hopefully bring their water back in line with what pool and spa water professionals consider healthy.

This seems like a good time to end today’s posting. Later we will go into the different methods a person can use to test their OWN pool or spa water: At-Home Pool & Spa Water Test Kits & Water Testing Meters and At-Home Pool & Spa Water Test Kits and Testing Supplies

Tomatoes and salmonella poisoning made the news again and with them came some startling scientific revelations. An article written by Lauran Neergaard (AP Medical Writer) and released/published on June 23, 2008 revealed new information about how tomatoes may possibly trap, carry, and incubate salmonella.

“WASHINGTON – Pick a tomato in the blazing sun and plunge it straight into cold water. If that happened on the way to market, it might be contaminated. Too big of a temperature difference can make a tomato literally suck water inside the fruit through the scar where its stem used to be. If salmonella happens to be lurking on the skin, that’s one way it can penetrate and, if the tomato isn’t eaten right away, have time to multiply.

That doesn’t mean people shouldn’t wash their tomatoes — they should, just probably not in cold water.

But as the Food and Drug Administration investigates the nation’s outbreak of salmonella from tomatoes, the example shows the farm isn’t the only place contamination can occur — and checking things like water quality and temperature control in packing houses and other supply stops is one key to safety.”

This raises the question of what sorts of water quality parameters packing houses should monitor on a regular basis.

Sanitizer and Disinfectant Levels — If the water used to wash, rinse and cleanse the tomatoes contains enough sanitizer, then theoretically no salmonella or other forms of bacterialogical contaminants could survive in the water. No contaminants in the water means no contaminants that a tomato could ’suck up’ if submerged in cold water.

“Water is an automatic first suspect. Was clean water used to irrigate, mix pesticides sprayed on crops, wash down harvest and processing equipment, and wash field workers’ hands?

Then in packing houses, tomatoes often go straight into a dump tank, flumes of chlorinated water for a first wash. To guard against salmonella washed into the water in turn being sucked into the tomatoes, producers often keep wash-water 10 degrees warmer than the incoming crop, says food-safety scientist Keith Schneider of the University of Florida, also part of FDA’s tomato initiative.

Beyond packing houses, the industry points to cases where suppliers were shipped unwashed, warm tomatoes and dunked them in ice-water baths to firm them for further processing.

Another question: How often does the water have to be changed? Dirt, leaves and other sediment reduce the chlorine’s effectiveness.”

Produce handlers and packing houses could reduce the chances of accidentally passing fresh produce through improperly disinfected wash water by implementing test procedures and protocols which make use of simple, inexpensive chlorine test strips such as SenSafe^TM Free Chlorine Water Check, a product approved by the USEPA and by several states for drinking water compliance monitoring.

The manufacturer of this product also has dip-n-read test strips capable of detecting chlorine concentrations as high as 2,000ppm and as low as 0.005ppm.

“Salmonella in Tomatoes”

Article Written by MIKE STOBBE, AP Medical Writer.

ATLANTA – An outbreak of salmonella food poisoning first linked to uncooked tomatoes has now been reported in nine states, U.S health officials said Tuesday. Lab tests have confirmed 40 illnesses in Texas and New Mexico as the same type of salmonella, right down to the genetic fingerprint.

An investigation by Texas and New Mexico health authorities and the Indian Health Service tied those cases to uncooked, raw, large tomatoes.

At least 17 people in Texas and New Mexico have been hospitalized. None have died, according to the U.S. Centers for Disease Control and Prevention.

Another 30 people have become sick with the same Salmonella Saintpaul infection in Arizona, Utah, Colorado, Kansas, Idaho, Illinois and Indiana. CDC investigators are looking into whether tomatoes were culprits there, too.

In Texas and New Mexico, raw large tomatoes — including Roma and red round tomatoes — were found to be a common factor in the 40 illnesses. But no farm, distributor or grocery chain has been identified as the main source, said Casey Barton Behravesh, a CDC epidemiologist working on the investigation.

“The specific type and source of tomatoes is under investigation,” she said.

Salmonella is a bacterial infection that lives in the intestinal tracts of humans and other animals. The bacteria are usually transmitted to humans by eating foods contaminated with animal feces.

Most infected people suffer fever, diarrhea and abdominal cramps starting 12 to 72 hours after infection. The illness tends to last four to seven days.

Many people recover without treatment. However, severe infection and even death is possible. Infants, the elderly and people with weakened immune systems are at greatest risk for severe infections.

In Texas and New Mexico, the patients ranged in age from ages 3 to 82. Of the 40, 38 were interviewed. Most said they ate raw tomatoes from either stores or restaurants before becoming ill between April 23 and May 27.

Another 17 cases are under investigation in New Mexico, CDC officials said.

As a result of this recent outbreak of illnesses related for foodborne contaminants, many restaurants and supermarkets have pulled tomatoes off the shelf and/or stopped serving them until they hear an official OK from Federal, State and Local Health Officials.

So if you thought water testing had very little to do with the handling and processing of fresh produce such as tomatoes, you thought wrong. At each step of the handling process the quality and nature of the water used to sanitize/disinfect, wash, rinse and clean the dirt off of fruits and vegetables needs continuous monitoring.

Monitoring Free Chlorine Levels in (Produce) Wash Water:

Many fruit and vegetable packing houses rely upon the WaterWorks^TM Free Chlorine Check test strips with a detection range of 0-25ppm to let them know if the wash water contains enough free chlorine residual to effectively keep their finished product free of contaminants.

Monitoring Free Chlorine Residuals Used to Wash Equipment:

Healh officials on every level require the operators of fruit and vegetable processing plants to clean off their machinery with a strong disinfectant solution. WaterWorks^TM Free Chlorine (High Range) test strips have a detection range of 0-120ppm, a range well suited for monitoring the free chlorine residual levels in the solutions used to hose down (wash) the equipment in a fruit and vegetable processing plant.

Making Sure No Chlorine Remains on the Fruits and Vegetables:

The presence of chlorine residual on fresh produce leads to premature rotting of the product so workers in fruit and vegetable processing plants check the total chlorine levels in water used in the final rinse stage with products like the WaterWorks^TM Total Chlorine test strips before allowing the produce to go into its final packaging.

A while has passed since the last outbreak of a foodborne illness struck and made the news and events like this one have resulted in new policies and regulations for produce handlers, growers, packers, etc. getting created in California. See Leafy Green Marketing Agreement (LGMA) for additional details.

“In 2007 California farmers came together to raise the bar for food safety. As a result the California Leafy Green Products Handler Marketing Agreement (LGMA) was formed. Members of the LGMA are working collaboratively to protect public health by reducing potential sources of contamination in California-grown leafy greens.

To date nearly 120 handlers, representing over 99% of the volume of California leafy greens, have joined the LGMA. These companies have committed themselves to sell products grown in compliance with the food safety practices accepted by the LGMA board. LGMA membership requires verification of compliance with the accepted food safety practices through mandatory government audits. These food safety practices were developed by university and industry scientists, food safety experts and farmers, shippers and processors. California leafy greens are now grown under a unique system that has become a model for leafy green growers in other states.” ( source )

What does any of this have to do with water testing? Quite a bit, actually.

• All fresh produce gets rinsed several times during processing with water containing some form of disinfectant. At the end of each rinsing stage, the water must used must get tested to make sure it still has a certain amount of residual disinfectant. This helps to ‘guarantee’ the cleanliness of the product.
• The machinery and equipment (bins, conveyor belts, cutting tools, etc.) used during the processing of the fresh produce must get washed down thoroughly with water containing a certain concentration of sanitizer and then rinsed clean w/ sanitizer-free water until all traces of sanitizer have been removed.
• Gloves, boots, etc. worn by the staff working in produce packing houses must get sanitized with, and later rinsed clean of, sanitizers.

Commonly used sanitizers and disinfectants in the food preparation/processing industries include chlorine, chlorine dioxide, quaternary ammonia, hydrogen peroxide, and ozone.

As of January 1, 2006, all daycare centers in the State of North Carolina must have the ability to test the chlorine content in both their sanitizing and disinfecting solutions. Previously the law stated that they had to test only the chlorine concentration in their sanitizing solutions.

Chlorine concentrations in disinfecting solutions have to fall between 500 ppm and 800 ppm free chlorine and the test strips previously used by child care and daycare facilities only had to read free chlorine concentrations in the range of 50 ppm free chlorine to 200 ppm free chlorine.

The daycare/childcare kit containing Free Chlorine Check Ultra High II test strips directly satisfies the requirements and you can now purchase the product online at FilterWater.Com.

Waterworks(TM) Free Chlorine Check Ultra High II from has an easy-to-read color chart with acceptable chlorine concentration levels and instructions for mixing BOTH chlorine solutions clearly marked on each bottle.

To make life even easier on daycare and child care center operators, they can pick up a Childcare/Daycare Kit which includes (3) bottles of their North Carolina Licensed Child Care Association approved test strips, quarter cup and tablespoon measuring devices (for proper on-site metering of the bleach), and a copy of the procedures North Carolina wants child care workers to follow when mixing their sanitizing and disinfection solutions.

You can purchase the Childcare Sanitizer/Disinfectant Test Kit online at FilterWater.Com.