69 S-Phenyl Mercapturic Acid as Urinary Biomarker of Indoor Exposure in Children

Abstract

Abstract Indoor air quality is particularly important for children since they spend more than 90% of their time inside. If outdoor levels of hazardous hydrocarbons are principally traffic related, indoor levels also depend on a variety of sources such as heating and cooking systems, stored products and human behavior (e.g. smoking, cleaning). In this context, within the ENVIRONAGE cohort, was investigated the relationship between SPMA urinary concentration in 214 children (4 to 6-year-old), and indoor sources of air pollution like heating and cooking methods (gas based vs electric) and traffic related air pollution (focusing on NO2 and black carbon). The SPMA urinary concentration was determined developing a high-sensitive UPLC-MS/MS method (LOQ: 0.05 ng/mL). Parents of the children were asked, throughout questionnaire, information about sources of indoor air pollution, such as wood-burning stove, fireplace and gas-based methods of heating or as energy source for the cooking stove and their frequency of using. Interpolation techniques was used to model the regional background levels of NO2 and black carbon for each child's residential address. The use of gas based cooking methods in the residential home of the child was associated with a 74% increase in the mean SPMA concentration of the child (95% Cl: 1.07 to 2.83), correcting for sex, age, BMI, waist circumference, passive smoking, education level of the parents, and time of the day. Consequently, this finding indicates that urinary SPMA can be used as biomarker for looking at indoor determinants of hazard hydrocarbons exposure.