ETS exposures in the California Teachers Study cohort
Initial Award Abstract
Despite strong evidence that exposure to environmental tobacco smoke (ETS) is a hazard to human health, there remain substantial and important gaps in our knowledge. Relatively little is known about the current and historical prevalence of exposure to ETS. Few studies have investigated characteristics that may be associated with ETS exposures. Furthermore, while the relationship of ETS to the development of lung cancer has been extensively researched, comparatively few studies have evaluated the contribution of ETS to the development of other diseases of concern. The specific aims of this research are designed to directly address these limitations in our knowledge. Our aims are: (1) to characterize patterns of historical ETS exposures in the home, in the workplace and in other settings for various time periods and birth cohorts; (2) to investigate the relationship of ETS exposures to other risk factors that may be important to health outcomes of concern; and (3) to conduct a preliminary short-term assessment of the association between reported historical ETS exposures and targeted health outcomes of interest, including cancer incidence and acute asthma episodes.
The study proposed here is an analysis of data collected as part of the California Teachers Study (CTS) from a cohort of 133,000 female California professional school employees who have completed detailed questionnaires concerning personal and family medical history, diet, physical exercise, environmental exposures, reproductive history, alcohol consumption, and active and passive smoking. The data collected from the CTS surveys are unique among large studies, such as this, in the availability of extensive lifetime ETS exposure -- encompassing exposures in the home, workplace and in other settings during childhood and each subsequent decade of life. Information on the quantity and quality of exposure in each of these settings and time periods was collected as well. Health outcome data will be obtained from linkage to California's statewide cancer registry and hospital discharge data sets. Information on environmental risk factors will be obtained both by questionnaire and by linkage of the cohort to census and various statewide environmental databases.
Many studies of ETS-related health risks have relied only on exposure from a smoking spouse and have been limited in their ability to adjust for other risk factors of interest. Additionally, most research on the influence of ETS on the risk of cancer has focused on exposures in the home as adults; very little is known about cancer risk associated with childhood ETS exposures. In contrast, we will have information on ETS exposures in the home, workplace and in social settings throughout each person's lifetime. Thus, we will be able to examine risks associated with exposures at different ages and in all types of settings. Through the use of data collected by the CTS questionnaires, we also will be able to adjust our estimates of risk associated with ETS exposures to account for a host of other factors that may play a role in the development of cancer or exacerbation of asthma.
Our research objectives are directly related to the ultimate goal of reducing the use of tobacco. Understanding the patterns and correlates of active and passive smoking is critical in planning targeted public health interventions. Establishment of baseline exposure profiles is necessary to evaluate future initiatives to reduce ETS exposures. Furthermore, a greater understanding of diseases related to ETS exposures could lead to more health protective legislation regulating exposures and greater public awareness of the consequences of tobacco use - both effectively working to reduce exposures to ETS and ultimately the prevalence of active smoking. |