The state Department of Health Safe Drinking Water Branch announced last month that it had found 1,2,3-trichioropropane (TCP) in samples of drinking water obtained from the Waialua Sugar Pump 3 water system. The pesticide 1,2-dibromo-3-chloropropane (DBCP) also was detected in the same well. Nearby city Board of Water Supply wells also tested positive for DBCP and for trichloroethylene (TCE).
The Waialua Pump 3 well, operated by Waialua Sugar Company, was put into service just last March to replace the Pump 17 well. Pump 17 was removed from service because levels of TCP in samples collected from April 1992 through March 1993 exceeded the state standard in four consecutive quarters.
Data collected by the state Department of Health show contaminant levels increasing over time in the Waialua area. In 1991, TCP levels in Pump 17 averaged 500 parts per trillion (the state maximum standard for drinking water is 800 ppt). In the 1992-93 period cited above, the average level of TCP was nearly twice that (900 parts per trillion).
When the Pump 3 well was sampled in March 1994, the presence of TCP was detected at a range of between 200 and 500 parts per trillion. According to the Department of Health staff, the tests used cannot pin down the concentrations more specifically than that, leading them to term the finding “non-quantifiable,” or NQ. Below the NQ concentration lies the ND, or “non-detectable.” A finding of ND means that whatever chemical contamination may exist is below the detection limits of the instruments used by the testing laboratory.
DBCP
Concentrations of DBCP also appear to be rising. At Pump 17, DBCP levels in the first quarter of 1993 stood at 65 parts per trillion. The state maximum contaminant level, or MCL, for DBCP is 40 parts per trillion.
When those first-quarter 1993 rest results for DBCP were obtained, the Department of Health notified Waialua Sugar Company, Inc., urging the company to undertake actions to reduce the concentration of the chemical in the water system, which serves about 200 households in the Kawailoa Camp. Alternatives mentioned by the Department of Health included installation of a treatment system to remove the contaminant; diluting the contaminated water to below-MCL levels by mixing it with clean water from other sources; or providing alternative water sources, such as bottled water, for potable use.
The Department of Health continued throughout 1993 to warn Waialua Sugar about the need to find an alternative source to Pump 17. In October, it finally issued a Notice of Violation for the DBCP contamination, which in one sample (taken February 17, 1993) had been double the maximum contaminant level of 40 parts per trillion.
At this time, Waialua Sugar began developing plans to put Pump 3 into use, although the switchover did not occur until March 1994. In the meantime, Waialua Sugar provided water service through an emergency tank which, however, had its own set of contaminant problems. According to a letter dated December 29, 1993, to Waialua Sugar from the Department of Health, “special microbiological sampling done on December 7, 1993, at the existing emergency tank showed that non-coliform colonies were too numerous to count (TNTC)… Replacement sampling done on December 9, 1993, again showed that non-coliform colonies were TNTC.”
Although state law allows penalties up to $25,000 for each day of violation of safe drinking water regulations, no fines were imposed by the Department of Health against Waialua Sugar. According to a staff person, because Waialua Sugar tried to work with the department in coming to a resolution of the problem, the question of fines did not arise.
A Matter of Time?
Initial tests of Pump 3 in November 1993 did not detect DBCP, although TCP was present in the non-quantifiable range. Later tests – in March and June 1994 – revealed DBCP in the NQ range. In late June 1994, the Department of Health notified Waialua Sugar Company of the test results. “The DOH is concerned about the presence of TCP and DBCP in the Pump 3 source”, wrote William Wong, chief of the Safe Drinking Water Branch. “The concentrations of the two contaminants are not yet at the MCL; however, given the history of other wells in the area, it is not unlikely that the concentrations will increase.”
In July 1994, Pump 3 tests showed DBCP once again below the detectable level of 20 parts per trillion.
City Water Works
Nearby wells hooked into the City and County of Honolulu’s Board of Water Supply also are showing signs of contamination. Tests in 1993 showed DBCP present in the non-quantifiable range – although the upper limit of the NQ range (which lies between 20 and 40 parts per trillion) is also the state’s Maximum Contaminant Limit for DBCP.
The state Department of Health has given water suppliers the benefit of the doubt when attempting to calculate average contamination over a year’s worth of samples. (This annual average is, generally speaking, the basis upon which compliance or non-compliance with state standards is determined.) Every sample where DBCP is detected in the NQ range is assigned a value of 20 parts per trillion – at the lower end of the NQ scale. As the DOH describes this practice, “A DBCP concentration falling into the range of 0.02 to 0.04 ppb [parts per billion] is considered for averaging purposes to be 0.02 ppb.” The Board of Water Supply has itself tested water at two Waialua-Haleiwa wells, apparently using a more sophisticated detection system. In a letter to the Department of Health December 22, 1993, DBCP levels were placed at 30 ppt Waialua) and 40 ppt (Haleiwa).
Other contaminants include TCP at 500 parts per trillion at the Waialua and Haleiwa wells, and trichloroethylene (TCE) in the non-quantifiable range (below 500 ppt) at the Waialua well. The state Maximum Contaminant Level for TCE is 500 parts per trillion.
To deal with the contamination problem at Waialua, the Board of Water Supply is proposing to move Granular Activated Carbon (GAC) contractors from Waipahu to Waialua. The GAC contractor functions much like a charcoal filter. Treatment of water at the Waipahu wells is no longer needed, the BWS says, because contaminant levels are now below state MCLs.
Human Guinea Pigs Show TCE’s Harm
Much of the information that exists on the harmful effects of exposure to DBCP, TCP, and TCE derives from animal studies. In the case of trichoroethylene, however, some 1.5 million New Jersey residents were exposed to elevated levels of TCE, PCE (perchloroethylene), or both, in their drinking water over a period of several years.
Reliable data exist to document both the exposure and the incidences of two types of disease – leukemia and non-Hodgkin’s lymphoma among the exposed population. Because of this, it was possible for scientists from the New Jersey Department of Health to study the data, as well as comparable data from a population that was not exposed to any of the chemicals.
The results of their study were published in the June-July 1994 edition of Environmental Health Perspectives.1
The scientists found that in towns where TCE in drinking water exceeded 500 parts per billion, adult women were almost one and a half times as likely to get leukemia as women who were exposed to water with TCE at lower concentrations. Younger women and girls (under the age of 20) exposed to drinking water with the higher concentration had a rate of acute lymphocytic leukemia more than three times that found in their non-exposed cohorts.
Among people exposed to between 10 and 500 parts per trillion of TCE in their drinking water supplies. Rates for leukemias and non-Hodgkin’s lymphoma were higher for women than in the control population.
Rates among men were also elevated in most cases, although they were not quite as high as the rates for women.
Chemical Cocktails
DBCP is a soil fumigant that was used to control nematodes in pineapple fields until 1985, when it was banned by the Environmental Protection Agency. It is a suspected cancer-causing agent and also is known to harm the kidneys, liver, and reproductive system.
TCP also has been determined to be cancer-causing and to impair functioning of the heart, liver, kidney, and central nervous systems. It is a solvent that was used in the application of DBCP.
TCE is a probable cancer-causing agent and can suppress functioning of the central nervous system as well as impair liver and kidney function. It was widely used as a cleaning and degreasing agent in Army equipment repair shops and laundries. TCE also was an inert ingredient in the manufacture of some pesticides.
1 Perry Cohn, Judith Klotz, Frank Bove, Marian Berkowitz, and Jerald Fagliano, “Drinking Water Contamination and the Incidence of Leukemia and Non-Hodgkins Lymphoma,” Environmental Health Perspectives, Vol. 102, pp. 556-561 (June-July 1994).
Volume 5, Number 5 November 1994
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