The state Department of Health Services, which set the guideline, has had an informal policy of requiring utilities to notify customers when water exceeds action levels. The state advisory standard merely represents a scientific guess as to the amount of TCE in water that could raise, by a minimal amount, each person’s already considerable risk of eventually getting cancer.Įxperts say that about 30% of Americans living today eventually will contract some form of cancer, and that the percentage will be greater for people who smoke. TCE is not a proven human carcinogen but has caused cancer in laboratory animals exposed to large doses. Test results show that average TCE levels have topped 4 ppb but have never averaged five ppb during any one-year period. McReynolds said that, in effect, the action level, which is not a legal standard, never was violated because it is intended to limit chronic rather than temporary exposure to TCE.
The measurements were taken from a water supply conduit-not at the tap-making it likely that some of the TCE, which is highly volatile, evaporated before reaching customers, DWP officials say. The DWP tests showed that monthly average concentrations of PCE have never topped the action level for that chemical since monitoring began more than three years ago. “They’ve not been put at any greater risk.”ĭuring the last five years, many wells have been found to contain TCE and a second common industrial cleanser, perchloroethylene, or PCE, at levels above state advisory limits, also known as “action levels.” In response, the DWP has stopped pumping from some of the wells and has blended water from others with cleaner aqueduct water to dilute the contaminants.īecause of these efforts, a 1983 DWP report says, “only water in compliance with the recommended quality guidelines was delivered to the customer for consumption.”īut DWP data shows that TCE in the well water averaged 6.6 parts ppb in June, 1984 8.3 ppb in May, 1984 9.1 ppb in November, 1982 7.1 ppb in October, 1982, and 8 ppb in both July and August of 1982. “I don’t think the public has been misled on it,” said Laurent McReynolds, assistant chief engineer of the water system. The data appears to conflict with public statements by the utility that its practice of closing polluted wells or blending their water has assured that water reaching customers is under the TCE limit.īut a high-ranking DWP official said there is no inconsistency between the test results and statements by the utility, since the yearly average of TCE in the water has stayed below the five-ppb advisory level. The letter says the advisory five-ppb level was an “annual average” and that the TCE levels were not approaching the 20-ppb level that had been set as a “daily” limit.ĭWP test data reviewed earlier by The Times shows that the average amount of TCE in water from the Valley wells exceeded the advisory standard of five ppb during four months in 1982 and two months in 1984. “While we agree with you that the public certainly should be informed when there is a health risk associated with their water supply, we are puzzled why you are requesting such public notice, since you agree with us that there presently is no health risk to any of the water customers in the city of Los Angeles.” But I would feel cheated if I was unaware of the increased risk.”Īfter the concern expressed by state officials, city officials agreed to help release the information.īut Ali Webb, press secretary to Los Angeles Mayor Tom Bradley, released a letter from DWP General Manager Paul Lane to state health department Director Dr. “We don’t consider it a public health threat, but we do believe the public has a right to know,” said Pete Rogers, chief of the sanitary engineering branch of the state health department.Īssemblyman Gray Davis (D-Los Angeles), a member of the Assembly Health Committee, said knowledge of the increased hazard, however small, should be available to the public so people could, if they wish, take precautionary measures such as buying bottled water until TCE levels in the water go down.ĭavis said: “I don’t intend to use bottled water myself. Still, state officials insisted that Los Angeles water customers be notified. In efforts to minimize the perception of danger, officials cited scientific estimates that, if a person drank two quarts of water containing five ppb of TCE for 70 years, he would have only a one-in-a-million greater chance of contracting cancer.
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