The View-Master Health Study Focus Groups

Article excerpt



Trichloroethylene (TCE) is a solvent used worldwide for degreasing metal parts (International Agency for Research on Cancer, 1995). TCE has been found as a contaminant in water, soil, air, food products, and animal tissues. The U.S. Environmental Protection Agency (U.S. EPA) has found TCE at 852 out of the 1,430 hazardous waste sites on the National Priority List (Agency for Toxic Substances and Disease Registry, 2003). According to Freeman and coauthors (2004), "The EPA has classified TCE as a probable carcinogen for humans. Studies have found increases in kidney cancer, liver cancer, non-Hodgkin's lymphoma, cervical cancer, Hodgkin's disease, multiple myeloma, and pancreatic cancer, although the association between exposure to TCE and cancer has been inconsistent across studies. TCE has also been linked with a variety of noncancerous conditions, including anemia and other blood disorders, stroke, urinary tract disorders, liver problems, kidney dysfunction, diabetes, eczema, and skin allergies." A recent report released by the National Research Council declared "the evidence on carcinogenic risk and other health hazards from exposure to trichloroethylene has strengthened since 2001 (National Research Council Committee on Human Health Risks of Tricholoroethylene, 2006)."

In 1998, chemical analysis of the water supply well at the View-Master factory in Beaverton, Oregon, found TCE at levels as high as 1,600 parts per billion, 320 times the drinking water standard established by U.S. EPA. The Oregon Department of Environmental Quality (ODEQ) estimated that TCE had contaminated the drinking water at the View-Master plant for more than 30 years (Freeman, Heumann, Douglas, & Foster, 2004). A feasibility study done by the environmental and occupational epidemiology unit at Oregon State Public Health (EOEOSPH) included an assessment of mortality in the worker group and found statistically significant increases in deaths from kidney cancer in women (Proportional Mortality Ratio [PMR] = 6.21, p [less than] .01) and two types of digestive cancers in men (PMR = 8.41, p [less than] .05). Site factors, including a large cohort (13,700) and long-term exposure to TCE without the presence of other organic solvents, provide a unique opportunity for investigation of potential health effects (Freeman, Heumann, Douglas, & Foster, 2004). Any epidemiologic study on this cohort must estimate exposure as accurately as possible; without historical measurements of TCE levels in drinking water, classification of exposure must be based on self reports or proxy reports of employment and water ingestion. Therefore, focus groups were conducted to define the types and ranges of opportunity for exposure to TCE, through plant operations and ingestion of contaminated water from the on-site well.

Purpose of the View-Master Focus Groups

Lobdell and co-authors (2005) noted that environmental health researchers have under-utilized qualitative research techniques such as focus group. According to Last (2001), a focus group is a "small convenience sample of people brought together to ... ascertain the range and intensity of their views." Designed to deepen understanding of complex phenomena, qualitative data interpretation is based on identification of recurring themes, implicit or explicit attitudes, and significant remarks. Focus groups can generate hypotheses, identify unknown sources of exposure, or confirm theories and findings (Cooper et al., 2001). They can be helpful in the design and construction of questionnaires (Cooper et al., 2001). Focus groups are exploratory in nature, and results are not expected to have external validity (generalizability), nor are they intended to be representative or statistically accurate.

The goal of the View-Master focus groups was to obtain information on plant processes related to the handling and disposing of chemicals, glues, and solvents, including protective equipment policies and unexpected events; the patterns of consumption and the quality of drinking water and other beverages prepared at the plant; and participants' attitudes regarding access to personal medical records. …