Today we will continue to explore the different drinking water filtration systems available to the general public by discussing briefly the specifics of a drinking water filtration system known as a Distiller.

• One part of a distillation system boils drinking water into steam and a second part recondenses the ‘purified’ steam back into water.
• Distillation systems may take the form of countertop models and point-of-entry (whole house) systems.
• Distillation systems work quite well for people whose unfiltered/untreated drinking water contains heavy metals and elements such as copper, cadmium, chromium, lead, mercury, arsenic, selenium, barium, fluroide and sodium.
• Some people opt to combine a distillation systems with an activated carbon system for more complete drinking water purification. Adding the activated carbon drinking water filter to the purification systems allows it to remove bad tastes and odors and a well-rated activated carbon filter will filter out many hazardous contaminants such as heavy metals, disinfection byproducts (i.e. haloacetic acids and trihalomethanes to name a few), chlorine, radon, volatile organic chemicals, parasites, and pesticides.

Many have asked the difference between the different types of drinking water filters they could use in their homes, at work, or at school.

Activated Carbon Filter:

• Positively charged and highly absorbent carbon media in the filter attracts and traps many drinking water impurities.
• You will typically find these drinking water filter systems on countertops, as point-of-use faucet filters, and under the sink.
• A good system for eliminating bad tastes and odors and a well-rated activated carbon filter will filter out many hazardous contaminants such as heavy metals, disinfection byproducts (i.e. haloacetic acids and trihalomethanes to name a few), chlorine, radon, volatile organic chemicals, parasites, and pesticides.

At this time the staff of Water Testing Blog does not know of a simple testing method for bromates. This does not mean companies who bottle water cannot have their product(s) tested for bromates.

“MWH Labs has received accreditation for testing of bromate by EPA Method 317 under the Stage 2 Disinfection/Disinfection Byproducts (DDBP) Rule. Method 317 is, a very accurate and very precise analytical method for bromate, that avoids many of the problems with false negatives and false positives that are associated with the existing analytical method (EPA 300.1). Additionally method 317 is capable of detecting bromate as low as 1 ppb (vs 5 ppb for method 300.1), helping clients to more accurately assess their bromate treatment options. Bromate is regulated in bottled water and potable water at a level of 10 ppb.”(source)

While oxidizers such as chlorine, bromine and chlorine dioxide do an excellent job of cleaning up water so that it contains no microorganisms and/or harmful strains of bacteria, their success as disinfectants does not come without a price.

Byproducts of the chemical reaction between the ‘bad’ components and the oxidizers form each time one of those ‘bad’ components gets eliminated and we call the disinfection byproducts. See below for a list of the ones listed in the National Primary Drinking Water Regulations for Disinfection ByProducts along with their MCL’s (Maximum Contaminat Levels) and potential hazards to humans:

• Bromate — Associated with an increased risk of cancer. Maximum Contaminant Level: 0.01 mg/L
• Chlorite — Associated with Anemia; infants and young children: nervous system effects. Maximum Contaminant Level: 1.0 mg/L
• Haloacetic acids (HAA5) — Associated with an increased risk of cancer. Maximum Contaminant Level: 0.06 mg/L
• Total Trihalomethanes (TTHMs) — Associated with liver, kidney or central nervous system problems; increased risk of cancer. Maximum Contaminant Level: 0.08 mg/L

Most water treatment facilities use some form of oxidizer to keep the water they distribute ’safe’ for human consumption. While the most prevalent way to disinfect water, use of oxidizers as disinfectants in potable water does come at a cost.

The process by which oxidizers break down organic contaminants generates compunds known as ‘disinfection byproducts’: Trihalomethanes (THM’s), Haloacetic Acids (HAA5), Bromates, and Chlorites.

Trihaloemethanes (THM): chloroform, bromodichloromethane, dibromochloromethane, and bromoform.

“EPA has published the Stage 1 Disinfectants/Disinfection Byproducts Rule to regulate total trihalomethanes (TTHM) at a maximum allowable annual average level of 80 parts per billion. This standard will replace the current standard of a maximum allowable annual average level of 100 parts per billion in December 2001 for large surface water public water systems. The standard will become effective for the first time in December 2003 for small surface water and all ground water systems.” (source)

Haloacetic Acids (HAA5): monochloroacetic acid, dichloroacetic acid, trichloroacetic acid and others.

“EPA has published the Stage 1 Disinfectants/Disinfection Byproducts Rule to regulate HAA5 at 60 parts per billion annual average. This standard will become effective for large surface water public water systems in December 2001 and for small surface water and all ground water public water systems in December 2003.” (source)

Bromate:

“Bromate is a chemical that is formed when ozone used to disinfect drinking water reacts with naturally occurring bromide found in source water. EPA has established the Stage 1 Disinfectants/Disinfection Byproducts Rule to regulate bromate at annual average of 10 parts per billion in drinking water. This standard will become effective for large public water systems by December 2001 and for small surface water and all ground public water systems in December 2003.” (source)

Chlorite:

“Chlorite is a byproduct formed when chlorine dioxide is used to disinfect water. EPA has published the Stage 1 Disinfectants/Disinfection Byproducts Rule to regulate chlorite at a monthly average level of 1 part per million in drinking water. This standard will become effective for large surface water public water systems in December 2001 and for small surface water and all ground water public water systems in December 2003.” (source)

Health officials and medical professionals have studied the effects of disinfection byproducts since the mid 1970’s and have found that in large doses, laboratory animals have developed serious, and sometimes deadly, health conditions. With regard to the effects these compunds have on humans, these same health officials and medical professionals have deterined that the current empirical evidence indicates a potential danger to humans and thus a need for additional research and study.

They also believed that the empirical data had enough merit to warrant restrictions on the amounts of disinfection byproducts in drinking water: Stage 1 Disinfectants/Disinfection Byproducts Rule.

“In sum, EPA believes the weight-of-evidence presented by the available epidemiological studies on chlorinated drinking water and toxicological studies on individual disinfection byproducts support a potential hazard concern and warrant regulatory action at this time such as that taken in the Stage 1 Disinfectants/Disinfection Byproducts Rule.” (source)