Chemical hazards in drinking-water - heptachlor and heptachlor epoxide
Heptachlor and heptachlor epoxide are considered in the WHO Guidelines for Drinking-water Quality. You can link from here to:
The Guidelines for drinking water quality also consider for individual chemicals:
Aspects of analytical achievability [Section 8.3, pp. 157-166]
Technical achievability (through treatment and other means) [Section 8.4, pp 166-184]
Rolling revision of the WHO Guidelines for Drinking-water Quality
Heptachlor is included in the plan of work of the rolling revision of the WHO Guidelines for Drinking-water Quality.
WHO has received a comment that the guideline value for heptachlor was withdrawn in the third edition because it occurs in drinking-water at concentrations well below those at which health effects may occur, even though the recent CICAD on heptachlor cites two not very old (USA) studies which appear to contradict this.
Progress to date
The Guidelines for Drinking-water Quality Working Group meeting (Geneva, 2005) determined that there is no need for a background document on heptachlor, as the only occurrence data consist of municipal wastewater data and occurrence in one well in the USA (from draft CICAD on heptachlor).
Other publications of interest
- Chemical safety of drinking-water: Assessing priorities for risk management (in preparation)
- Protecting groundwater for health: managing the quality of drinking-water sources (in preparation)
- Managing surface waters for health (in preparation)