| The main goal of this research was to determine which household characteristics and activities influence levels of residential contamination. The data were characterized by examining for seasonal, urban/rural, indoor/outdoor and longitudinal differences. Children's exposures were also assessed.;The data used in this thesis were collected during EPA Region V National Human Exposure Assessment Survey (NHEXAS). Levels of cadmium (Cd), chromium (Cr), arsenic (As), lead (Pb), particulate matter (PM), 1,1,1 trichloroethane, p-dichlorobenzene, benzene, chloroform, styrene, tetrachloroethylene, toluene, trichloroethylene, m,p- and o-xylene were measured in multiple media. Questionnaire data on household characteristics and activities were collected at the same time.;Factor analyses yielded factors for gasoline, dust mass/metals, solvents, tobacco smoke/smoking, metals in urine, p-dichlorobenzene exposure, suburban-type homes, rural, older homes, dilapidated homes, combustion, construction, cleaning and cooling.;Discriminant analyses predicted volatile organic compounds (VOCs) when gas powered devices, mothballs, and carpets were present. Metals were associated with chipping paint, window replacement and smoking. Construction and cleaning activities predicted levels of PM in indoor air and on living area surfaces. Dust, smoking, and room deodorizers were associated with VOCs and metals. Smoking predicted PM, Cd, and benzene. Benzene, toluene and m, p-xylene were associated with gasoline. Dilapidated homes predicted PM, Pb, and Cd in indoor air, Pb on window sills and dust mass. Suburban homes predicted toluene, m,p-xylene, benzene and As in indoor air.;High levels of contamination were associated with smoking, dust, chipping paint, window replacement, older buildings and lower household income. Levels of contamination and selected activities were consistent across visits. Levels of contamination were higher inside the home. Levels of contamination were higher in the urban environment. Indoor air levels of benzene, styrene, xylenes, p-dichlorobenzene and tetrachloroethylene were higher in winter. Potentially 27% of the children may have had a health risk due to tetrachloroethylene exposure and less than 10% of the NHEXAS children may have been at risk from p-dichlorobenzene, toluene and chloroform inhalation exposure. Health risks of the sample population from lead exposure varied from 100% to 6% depending if the reference dose or clearance levels were used for comparison.;The results of these analyses indicate that data collected on residential characteristics and activities can be useful as predictors for the presence of VOCs and metals in the residence. These can be of major value as one component of the criteria for completing measurements for quantitative analyses of residential exposure. |
