Federal-provincial Subcommittee on Drinking Water - 26th Meeting, Regina, Saskatchewan, May 15 - 16, 2000

The twenty-sixth meeting of the Federal-Provincial Subcommittee on Drinking Water (DWS) was held in Regina, Saskatchewan, on May 15 and 16, 2000. The development of new guidelines and revision of existing guidelines were discussed for the following substances:

Aluminum

The industry/government aluminum task group is still awaiting funding.

Arsenic

The Secretariat is awaiting the US Environmental Protection Agency (EPA) health assessment of arsenic before proceeding with a reassessment of the Canadian guideline.

Chlorate-Chlorite-Chlorine Dioxide

Chlorate and chlorite are by-products of chlorine dioxide disinfection. Health Canada has assigned an evaluator to assess US EPA information on this subject; a draft document may be available in the fall. Health Canada's research lab is conducting a study to look at a suite of 26 chlorinated disinfection by-products from appropriate treatment plants. Members discussed the emergence of chlorine dioxide units in their jurisdictions.

Chloral Hydrate

Research has been completed on the 90-day toxicological study, and the final analysis is being conducted. The report should be available soon.

Copper

The Secretariat is gathering exposure data on copper from the provincial representatives. The EPA and the World Health Organization may reassess their guidelines in the near future.

Cyanobacterial Toxins

- (Microcystin-LR) - Both the analytical method and the field test kit developed through a partnership between Health Canada and the University of Alberta will be validated through testing this summer. The field test kit may also be used by the agricultural and food industries. The Toxic Substances Research Initiative study looking at tumour promotion is on-going; data should be available by next summer. Members postponed voting on the proposed Microcystin-LR guideline of 1.5 µg/L until the fall meeting.

Cyanogen Chloride

The first draft of the health assessment has been completed.

Fluoride

The Canadian Council of Ministers of the Environment (CCME) is changing its guideline for fluoride in freshwater to below 1.5 mg/L, and that the major source of inorganic fluoride in inland waters is from intentional additions to drinking water (except where there is an industrial source). Health Canada will include fluoride exposure in the next food basket survey. Members agreed that the Subcommittee may want to re-examine the fluoride guideline once the data gaps have been filled and the results of the Food Basket survey have been released.

Haloacetic Acids

Three-quarters of the assessment is complete.

MCPA

The first draft of the assessment has been completed, though additional exposure data may be added.

Microbiological - Bacteriological

The revised bacteriological document has been translated and is awaiting Health Canada's approval. Once the approval process is complete, the document will be posted on the Health Canada's water quality website.

Microbiological - Protozoa

The protozoa document should be posted on the website by mid-June.

Methyl tertiary-Butyl Ether (MtBE)

Members are monitoring for exposure to MtBE in their jurisdictions. Environment Canada is tracking the presence of MtBE in the environment from a clean fuel perspective. The US is looking to ban MtBE because of gasoline contamination in ground water. WHO has place MtBE on a list of chemicals for future evaluation, but it may only be relevant to mainland North America.

Trichloroethylene

Members discussed the public's concerns with trichloroethylene, and decided that the Subcommittee should take advantage of CEPA's assessment of the substance by reassessing the drinking water guideline once more information becomes available.

Trihalomethanes (CDBPs Project)

Members were given an update on the progress of the Chlorinated Disinfection By-Products (CDBPs) task group. A status report will be posted on the water quality website, along with a summary of by-products and health effects.

Turbidity

The draft document for the turbidity guideline is being prepared and may be distributed to members for comment by the fall meeting.

Priority List

The substance priority list, located on Health Canada's water quality website ( www.hc-sc.gc.ca/waterquality ), will be up-dated after the fall Subcommittee meeting.

Other Reports Given and Items Discussed Include:

• Status of dichlorprop, haloacetonitriles, MCPA, nonylphenols and viruses assessments
• The development of Canada-Wide Standards related to drinking water
• Reports from certification organizations on their evaluation programs for drinking water treatment components, additives and treatment units
• Provincial regulations related to drinking water quality