Woburn is a blue-collar town of about 35,000 people, located approximately 10 miles north of Boston. It has always been and still is inhabited by young families with children and, interestingly, dates back to the 1600s. The Aberjona River flows through the town and there have been, since the Industrial Revolution, multiple chemical and other companies on its banks that have dumped toxic products into the river. A consultant hired by the town in the 1950s said that the water was too toxic to use. Nonetheless, in 1964 the town authorized the digging of two wells that drew water from the river.
In 1972, Jimmy Anderson, age 3, was diagnosed with pediatric acute lymphocytic leukemia (ALL). His mother, Anne Anderson, started taking him to the office of Dr. John Truman, a prominent pediatric hematologist/oncologist at Harvard, for treatment. As she would sit with him week after week patiently waiting for treatment and chatting with the other mothers, she noticed that a few of the other mothers were also from Woburn. Not only that, they seemed to live in fairly close proximity to her—one from the same street, and some others from within a radius of a half mile.
While Anderson suspected there was something wrong with the water, which apparently smelled, what brought things to a head was the discovery in 1979 of several barrels of chemicals next to the river. This brought in state investigators who tested two of the wells. They discovered high levels of trichloroethylene (TCE) and tetrachloroethylene (PCE), both known to be carcinogens. This led to a town hall meeting where a large number of other cases in Woburn were also identified.
What ultimately made the situation more interesting than the usual cluster was the involvement of Mel Zelen, the chair of biostatistics at the Harvard School of Public Health, who calculated the probability of the number of cases and the size of the population, and concluded that this was indeed an anomaly. By the time Anderson was done, she had identified 28 leukemia cases between 1969 and 1986, more than four times the expected rate. Unfortunately, 12 of these cases, including her own son, Jimmy, died from the disease.
What was the source of these chemicals? The main culprits were judged to be the Beatrice Foods Company and the W.R. Grace Company. These chemicals were used to clean tools and to thin paint. Both companies would dump barrels of these chemicals “out back.”
Ultimately eight of these families brought suit, as is described in the movie “A Civil Action.” The attorney for the plaintiffs, Jan Schlichtmann, was played by John Travolta, and it is questionable how true to life the movie is. In a partial verdict, Beatrice Foods was found not responsible, and subsequently the plaintiffs settled with W.R. Grace for $8 million, of which more than a third went for expenses and lawyer fees. The families themselves received relatively little.
Clusters are very common. So what makes the Woburn cluster distinctive and worthy of our attention?
1. It was the first such toxic cluster case to achieve such prominence and at least some degree of success from a litigation point of view.
2. It did fulfill some of the hallmarks of a “real” cluster—an uncommon or rare cancer; multiple cases; a definable plausible etiology.
3. I liked the movie.
An epidemic is also a cluster—a statistically significant excess of cases of a disease in a time-space continuum. But when we label it as an epidemic we have given the official imprimatur of being something more than a random outlier on the bell curve, something more than pure chance.
But it does bring up other issues in such cases from a legal perspective (OK, I am not a lawyer, so take this for what it is worth.) The court case was divided into three phases because of its complexity. The first phase was for the jury to determine if the chemicals from the companies had indeed penetrated into the drinking water. This part of the trial consisted of 78 days of testimony on highly complex geology and hydrology and engineering. Then the jury, which consisted of a postman, some housewives, etc., had to make that decision. One really has to question the validity of such a decision.
Of course, another movie, “Erin Brockovich,” brought some of these same issues to bear. And clusters are indeed a natural part of our universe—the outliers on the bell curve. When a cluster represents something more than the natural operations of chance, it can be a difficult thing to determine.
Was the Woburn cluster an epidemic? What if you were in the jury box?
We will have the opportunity to discuss further clusters in the future in Thoughts on Cancer.
Alfred I. Neugut, MD, PhD, is a medical oncologist and cancer epidemiologist at Columbia University Irving Medical Center/New York Presbyterian and Mailman School of Public Health in New York.
This article is for educational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment, and does not constitute medical or other professional advice. Always seek the advice of your qualified health provider with any questions you may have regarding a medical condition or treatment.
