Published in the Asbury Park Press
By JEAN MIKLE
TOMS RIVER BUREAU
TOMS RIVER -- It must be the water.
For years, that has been the belief of many people in Dover Township who have long linked the township's lengthy history of ground water contamination to the higher than average levels of childhood cancer here.
So when state and federal health officials this week released a report that revealed some early findings from an ongoing epidemiological study of families whose children developed cancer, it was perhaps only natural that some residents focused on just a few facts.
Mothers whose children developed leukemia, for example, were more likely to recall drinking four or more glasses of tap water a day while they were pregnant, and children who developed leukemia, brain or central nervous system cancers were also more likely to have consumed four or more glasses of tap water daily.
Researchers cautioned that no conclusions should be drawn from the preliminary study, noting that the report does not say whether the tap water consumed by mothers and children came from private wells, Dover's public water supply, or even from a water supply in another town.
"This is preliminary information," said Dr. Eddy A. Bresnitz, an epidemiologist with the state Department of Health and Senior Services, during a presentation on the interim report at the Dec. 13 meeting of the Citizens Action Committee on Childhood Cancer Cluster. "There are no conclusions you can walk away with today."
But Michael Gillick, a 20-year-old man who has battled a form of brain cancer for almost his entire life, said he is concerned that people not think the interim study results indicate nothing is wrong in Dover.
"A lot of people have been going around saying there isn't a problem," Gillick said. "Tap water use was more common . . . There was a positive association between that and leukemia, right?"
"It doesn't say anything about where they lived, whether it was public, private water," Bresnitz responded. "I wouldn't walk out of the room drawing any conclusions about that."
Indeed, health officials pointed out that there were other, similar, associations found in the preliminary report, which looked at several potential cancer risk factors, including family medical history, diet, exposure to tobacco smoke and alcohol, and exposure to items like household chemicals, animals and electromagnetic fields caused by home appliances.
Children who developed cancer were more likely to have higher birth weights (over 9 pounds), and be born to mothers who had inadequate prenatal care and took fewer prenatal vitamins. Children who developed cancer were also more likely to have used electric blankets or electric mattress pads.
"We're not just looking at the water," said Jerald A. Fagliano, a state epidemiologist. "We're trying to do as comprehensive an examination as we can."
Richard Henning, a spokesman for United Water, the parent company of United Water Toms River, said it is far too early to draw any conclusions from the data.
United Water Toms River serves about 95,000 customers in Dover and Berkeley townships and South Toms River.
"We still have so much further to go within this investigation," said Henning. "That's why it's wrong to draw any conclusions from any of the information that has come out so far."
Officials from the state health department and the federal Agency for Toxic Substances and Disease Registry, who are working together to complete the epidemiological study, noted that no information about family's residence history, proximity to hazardous waste sites and exposure to air pollution sources was included in the interim report.
That information will be part of the final epidemiological study, which is scheduled for release by the end of next year.
The residence history is important because researchers hope to use a historical model of Dover's water system to find out if families of children who developed cancer ingested more polluted water than families whose children did not contract the disease.
Researchers have long cautioned residents not to draw any conclusions until all studies are completed, and have never guaranteed that there will ever be a definitive answer that would explain Dover's higher than average childhood cancer rates.
But federal and state officials own interest in the potential connection between polluted water and childhood cancer became clear when they agreed in early 1997 to construct a complicated model of Dover's water system in an attempt to determine families' water consumption.
Researchers said a past history of water contamination, coupled with the discovery of styrene acrylonitrile trimer in two United Water wells in November 1996, led to the decision to create the water system model. The toxicity of the trimer, a byproduct of plastics production, is not yet known. Toxicity studies are ongoing.
The federal agency is expected to turn over results of the water modeling to state officials by the end of January, according to Juan J. Reyes, director of ATSDR's office of regional operations.
Researchers will use the water modeling data along with residence history in an attempt to determine the amount of water used by families who participated in the massive epidemiological study.
The study includes interviews with 40 families whose children were diagnosed with leukemia, brain or central nervous system cancers while living in Dover between 1979 and 1996. Children ages infant to 19 were included.
Those 40 families were matched with 159 control families, whose children did not develop the disease. Each control group child was matched on age, gender and residence in Dover during the month that a specific child with cancer was diagnosed.
A companion study of birth records, which involved no family interviews, looked at 48 children with cancer whose mothers lived in Dover at the time of their births. These children were matched with 480 control group children.
The interview study relies on participants' recall of habits, diet and lifestyles up to 35 years in the past. "Some of the information is easy to recall, and some may not be as easy," Fagliano said.
The interim report notes that "a potential weakness of the interview study is that the parents of cases (children with cancer) may have differentially recalled their children's actual exposure histories, when compared to control children (who did not develop cancer."
To minimize that potential bias, researchers did not make the interview questionnaire available to the public until after the completion of all interviews, and used experienced interviewers to ask the questions, the report says.
James S. Blumenstock, senior assistant commissioner for the state health department, admitted it is not normal practice to release preliminary findings in the middle of an epidemiological study.
Blumenstock said officials' commitment to be open about sharing information with the community led to the decision to release the interim report last week. By releasing data that is only preliminary, researchers are aware that residents could use the data to draw conclusions that can not be scientifically substantiated.
"It's a risk you take," Blumenstock said. "It seemed to be a logical break-point to us." Concern that people could draw improper conclusions from preliminary data led state officials to undertake "a painstaking effort" to explain the interim report to both the families involved, the press and the public, he said.
Scientists held a private meeting with 35 families of children with cancer on Dec. 12, the day before the report was released to the public, and also briefed the media before the information was presented to the public Dec. 13, he said.
Linda L. Gillick, who chairs the citizens committee, said the interim report "gives us some indicators of some possibilities. We seem to be on the right track here. When we put all this together, maybe we'll have some answers, and it could be more than one answer."
Published: December 19, 1999
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