Summary (1995-2000)

The main goal of this program is to assess and understand risk to human health from toxic substances in the environment using an approach that integrates exposure assessment, biological pathogenesis and epidemiological studies. The individual projects focus on assessment of exposure and disease in relation to metals (arsenic, lead, vanadium), polychlorinated biphenyls (PCBs), and pesticides. The program consists of nine projects (eight biomedical and one nonbiomedical), and four cores (administrative, analytical, training, and outreach).

There are four interrelated projects which focus on lead-related health effects. In one project, the relationships between environmental lead concentrations and uptake into bone are being measured both by standard blood lead levels and by K-x-ray fluorescence (KXRF) techniques. In another project, children with high blood lead levels are the subject of a study to determine whether deltaaminoevulinate dehydratase (ALAD) polymorphisms can serve as biomarkers to investigate an association between genotype, blood lead level, and susceptibility to neurophysiological dysfunction. Longitudinal studies in Mexico City are focussing on bone lead kinetics with respect to pregnancy and lactation. A related prospective study is assessing lead exposure and bone resorption associated with aging.

A second group of projects involves two epidemiological investigations which are examining the relationship between arsenic exposure (measured in toenail clippings) and cancer. One study focussing on non-melanoma skin cancer is a nested case-control analysis consisting of subjects from the Nurses Health Study and the Health Professionals Follow-up study (skin cancer). The other investigation is a case-control study in Taiwan which is surveying a probable association between bladder cancer and high levels of arsenic exposure. One closely related project, regarding the health effects of vanadium, integrates epidemiological studies (bronchial hyperreactivity and asthmatic bronchitis in exposed boiler workers) with cell/molecular biology experiments using animal studies and in vitro animal and human cell lines to study exposure- dose-response relationships.

A third group of projects is describing environmental degradation and potential exposure of humans to PCBs at a heavily contaminated site in New Bedford Harbor. A nonbiomedical project focuses on the assessment of ecosystem health by evaluating the interrelationships between microbes and pollutants. A PCB-related biomedical project is evaluating associations of in utero exposures to PCBs, pesticides, and lead with newborn and infant health outcome.

The three project cores (analytical, administrative, and training) are designed to provide support to the other individual projects within the program. The outreach core serves to disseminate information and technology regarding the research of hazardous substances, the management and handling of toxic materials, and the environmental and human health effects of exposure to harmful chemicals. By developing various programs and activities, including a Visiting Scholars Program in Environmental Health, a Future Search Conference, a Speakers Bureau, a Research Seminar Series, Continuing Education classes, and a Health Newsletter, the outreach core contributes extensively to the overall goal of the program. The program is also collaborating its research efforts with the following institutions: Boston's Children's Hospital, the Center for Disease Control and Prevention, and the National Cheng-Kung University Medical Center (Taiwan), Tufts University, Bigham and Womens Hospital and the Instituto Nacional de Salud Publico.