Dr. Neugebauer also reanalyzed the Borak study, using six bands rather than seven,7 extending four miles from the landfill center, and concluded that Borak’s data also showed that the risk of ALL increased with proximity to the landfill.
Plaintiffs also relied on the affidavit of Dr. Bruce K. Bernard, an expert toxicologist and biostatistician. In order to determine the general plausibility of a cause-and-effect relationship between an increase in the observed frequency of childhood ALL and exposure to chemicals emanating from the landfill, Dr. Bernard analyzed Dr. Neugebauer’s findings using the evaluation scheme propounded by Sir Austin Bradford Hill, a well-known epidemiologist and biostatistician. Hill’s approach involves analysis of nine factors: (1) strength of association, (2) consistency, (3) specificity, (4) temporality, (5) biological gradient, (6) biological plausibility, (7) coherence, (8) experiment, and (9) analogy.
Dr. Bernard found that strength of association was clearly demonstrated by comparisons between Band 1 and Band 2 versus Band 4, showing a very significant relationship between [88 A.D.3d 392] the incidence of childhood ALL and proximity to the landfill. Dr. Bernard found that Neugebauer’s data showed internal consistency with regard to a causal relationship. He opined that the question of external reproducibility turned on the availability of other studies such as animal experimentation and epidemiological studies. Dr. Bernard opined that many of the chemicals known to have been dumped at and emanating from the landfill are well-known, potent human and animal toxicants, mutagens and carcinogens. Dr. Bernard noted that benzene is a leukemogen causing acute myelogenous leukemia and a known risk factor in multiple myeloma and ALL, all closely-related injury.
Dr. Bernard acknowledged that epidemiological data was more limited since environmental, occupational and health data limited exposure to these toxic substances. Dr. Bernard noted that human health data on these substances was largely derived through occupational exposures (which, by definition, would exclude children) and the rare accident or case of malfeasance. Dr. Bernard opined that within these scientific and moral constraints, available data was consistent with the cause-and-effect hypothesis.
Dr. Bernard opined that there was high specificity in the case of the causal relationship between the landfill and childhood ALL. He noted that the proposed causal relationship was limited by age (i.e., children), general disease type (i.e., cancer), specific system (i.e., hematopoietic), disease entity (i.e., ALL) and distance from the landfill (i.e., bands).
As to temporality, Dr. Bernard noted that none of plaintiffs were diagnosed with their personal injury before dumping began and all lived in close proximity to the landfill.
As to biological gradient, Dr. Bernard opined that the data demonstrated a direct dose-response relationship between exposure and the disease.
Dr. Bernard noted that biological plausibility, was a question which turned on the etiology of childhood ALL, knowledge about chemicals in and leaching from the landfill, the potential human exposure to those chemicals and the known latency period for the development of childhood ALL. Dr. Bernard opined that available evidence supported a causal relationship between childhood ALL and exposure to a wide variety of substances, including ionizing radiation, pesticides, and organic solvents, such as benzene, found to have emanated from the landfill. Dr. Bernard noted that etiologies believed to be associated with the induction of leukemias, including childhood leukemias, have as their common mechanism mutagenic effects on chromosomal tissue.
As to coherence, Dr. Bernard opined that he was unaware of a conflict between the proposed relationship (i.e., an increase in childhood ALL and the chemicals dumped in and around the landfill) and established medical scientific data.
As to experiment, Dr. Bernard stated that he was unaware whether this data was available or had been analyzed.
Finally, as to analogy, Dr. Bernard noted that the Woburn case, although involving a different pathway, namely, drinking water, concerned exposure to the same chemicals involved in this case and the same medical sequelae.
To Be Cont,,,