Environmental chemicals mediated the effect of old housing on adult health problems: US NHANES, 2009-2010

Housing conditions affect occupants continuously, and health interventions have shown a positive association between housing investment or improvement and occupant's health. However, the sources of the housing problems were less understood. Since it was observed that lead dust and chloroanisoles released from housing (materials) as indoor pollutants affected child's health, we now aimed to examine the relationships among built year, environmental chemicals and individual health in adults in a national and population-based setting. Data were retrieved from the US National Health and Nutrition Examination Survey, 2009-2010, including demographics, housing characteristics, self-reported health status, biomarkers and blood and urinary chemical concentrations. Adults aged 20 and above were included for statistical analysis (n = 5,793). Analysis involved chi-square test, t test, and survey-weighted general linear regression and logistic regression modelling. People who resided in older housing built before 1990 tended to report chronic bronchitis, liver problems, stroke, heart failure, diabetes, asthma and emphysema. Higher values in HDL cholesterol, blood lead and blood cadmium and having positive responses of hepatitis A, B, C and E antibodies among occupants were also observed. Furthermore, higher environmental chemical concentrations related to old housing including urinary cadmium, cobalt, platinum, mercury, 2,5-dichlorophenol and 2,4-dichlorophenol concentrations and mono-cyclohexyl phthalate and mono-isobutyl phthalate metabolites were shown in occupants as well. Older housing (≥30 years) seemed to contribute to the amount of environmental chemicals that affected human health. Regular monitoring, upgrading and renovation of housing to remove environmental chemicals and policy to support people in deprived situations against environmental injustice would be needed.