Watermatters has terminated business with Berkey Water Systems

March 14th, 2023

Watermatters has been selling Berkeys since 2010. Berkey systems have been well loved by our customers for years. It is now time to end our relationship with Berkey due to ongoing ... More »

Trihalomethanes in Greater Vancouver Drinking Water

Chemical reactions happen when chlorine is added to water for disinfection purposes. Chlorine interacts with organic material in water forming hundreds of new compounds called disinfectant byproducts or chlorinated byproducts.

Trihalomethanes (THMs) are the most commonly known and researched of these compounds. You have probably heard of chloroform gas, one of many trihalomethanes.

Trihalomethanes (THMs) linked to cancer and birth defects.

Trihalomethanes are suspected to damage the liver, kidneys and central nervous system. They are also considered carcinogenic and have been linked to miscarriage and birth defects. Extra precautions are recommended during pregnancy.

THM risk in Greater Vancouver water supply.

Studies show increased cancer risk at exposure levels common in Greater Vancouver’s water supply. THM levels found in most ‘industrialized’ municipalities water supply increase the possibility of bladder cancer by 35%.

Greater Vancouver is supplied with surface water from mountainous watersheds which may contain a lot of organic content like leaves. This causes higher concentrations of trihalomethanes than may occur than in other municipalities that use ground water.

Trihalomethanes increase with heat and can also form in hot water heaters.

Hot showers increase trihalomethane exposure.

THMs are volatile gases that vaporize at temperatures lower than turn water to steam. While showering in an enclosed in a space that concentrates these toxic gases, you are inhaling them into your lungs and absorbing them through the opened pores of your skin introducing them directly into the bloodstream.

Most shower filters use a filtration media called KDF which is excellent for chlorine reduction but has absolutely NO impact on trihalomethanes.

Canada’s contaminant guidelines weaker than U.S. standards.

Canada is sadly lacking a clear national drinking water quality policy. Health Canada’s recommended maximum level for THMs in drinking water is 0.1 milligrams per litre (100 parts per billion). This is a guideline only and not enforced.

The U.S. has a more stringent standard – a maximum of 80 parts per billion.

Studies clearly indicate that serious health effects occur at much lower exposure levels (50 parts per billion).

Health Canada’s ‘official’ position on the guideline for trihalomethanes is that ‘cancer risk at this level over a lifetime is considered extremely low’. Health Canada must, however, have serious concerns about THMs and other chlorination by-products because a special task group has the current guidelines under review. The federal government is being challenged by advocacy groups for its weak and lacking regulations concerning toxic chemicals.

Other dangerous byproducts of chlorine.

HaloAcetic Acids (HAAs) are another important group of chlorinated byproducts for which there is currently no guideline in Canada. The U.S. maximum acceptable level is 60 parts per billion.

HaloAcetic Acids occur more readily in water with lower pH values. Water supplied to Greater Vancouver has low pH (acidic) and is being gradually adjusted to a higher pH (more alkaline) by the addition of soda ash to the water. The incentive for this is to protect pipes and plumbing from the corrosive effects of acidic water.

Chlorine is a cheap disinfectant but is it effective?

All chemical disinfectants create toxic byproducts including disinfection with ozone.

Chlorine (also a carcinogen), and its derivatives, are most commonly used in North America for water disinfection. It is the most inexpensive way to disinfect water. Although a biological poison, chlorine has significant limitations as an effective disinfectant.

What’s your solution?

Protection is certainly NOT guaranteed with bottled water which may contain trihalomethanes and a host of other toxic compounds.

Your best bet is a point-of-use drinking water filter that has been third party tested for high capacity reduction of chlorine, trihalomethanes and whatever other contaminants occur in your drinking water.