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Introduction During March 1988, 16 private residential shallow wells near a radar base in Sault Ste. Marie, Chippewa County, Michigan, were found to be contaminated with one or more environmental [...], During March 1988, 16 private wells in Sault St. Marie, Michigan, were found to be contaminated with one or more environmental contaminants. In accordance with the Michigan Environmental Response Act, the state provided the affected residents with bottled water for drinking purposes. Risk assessments for carcinogens (benzene, 1,2-dichloroethane, dichloromethane, trichloroethylene, and tetrachloroethylene) were formulated. The total excess cancer cases attributable to the consumption of contaminated water from these wells were estimated to be 14 per one million persons. The maximum concentration of chloroform in the city public water supply was 26 [µgrams]/L. The high concentration of chloroform was the result of chlorination of the unfiltered river water by the public water facility. The relative health risk from the consumption of chlorinated surface water from the public water supply system would be approximately 4.3 times greater compared to that of consuming groundwater from the contaminated private wells. The affected residents were given three options: (a) continue consumption of bottled water; (b) connection to the existing public water supply system; or (c) construction of deep water wells. The citizens voted for the second option of connecting to the public water supply system and voluntarily accepted the relatively higher health risk. The State of Michigan later proposed to further improve the water purity by upgrading the public water supply system by the incorporation of a filtration plant. The project was completed in August 1993.

Risk assessment methodologies form the basis for deriving guidelines for environmental contaminants in drinking water. A state may have to set, on an emergency basis, an interim guideline for a drinking water contaminant for which only limited data are available. Additional national drinking water standards will be useful for state regulatory agencies, because maximum contaminant levels (MCLs) are legally enforceable, but the risk assessment formulations of the regulatory agencies can be challenged. A state has to issue advisories and set interim guidelines for use of water for non-drinking purposes such as washing hands, cleaning dishes, taking baths, and showers, etc. The exposure to volatile organic compounds via inhalation and through dermal absorption during showering and bathing may be equal to the exposure from ingesting 2 L/day of the same water. Further research in this area is indicated. The implementation of drinking water regulations is costly for some local water supply programs and state regulatory agencies. There is a need to find solutions to this problem. This paper was presented at the symposium on Drinking Water Issues at the 12th Annual Meeting of the American College of Toxicology held at Savannah, GA on October 21–23, 1991. The opinions presented here are solely those of the author. They do not necessarily reflect the official policy of the author's organizational affiliation (Michigan Department of Public Health or FSTRAC) or of any state or other government agency. [ABSTRACT FROM PUBLISHER]

Residential wood smoke contains inorganic and organic particulates, ash, car bon monoxide, nitric oxide, nitrogen dioxide, formaldehyde, polycyclic aro matic hydrocarbons (benzo[a]pyrene, benzo[k]fluoranthene, benzo[b]fluoran thene, benzo[ghi]perylene, and indeno[1,2,3-cd]pyrene), phenols and sulfur dioxide. Benzo[a]pyrene and formaldehyde are classified as group B2 and group B1 carcinogens, respectively, by the United States Environmental Pro tection Agency. Reported concentrations and potential health risks of the released contaminants are discussed. In general, wood smoke is an irritant to the eyes, nose, and the respiratory tract. It has the potential to cause chronic respiratory problems. Because there are indications that wood smoke may cause adverse effects on human health, exposure to this source of air pollution should be minimized. [ABSTRACT FROM PUBLISHER]