Associations of Urinary Amino-PAHs With Ambient Air Pollutants in Beijing Residents

摘要

Background: Certain nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) are specifically emitted from internal engines especially diesel engines. Nitro-PAHs can be metabolized into amino-PAHs that are excreted in urine. Therefore, urinary amino-PAHs may serve as internal dose markers of traffic emissions. Aims: The present study is to examine whether the traffic restriction implemented during the Beijing Olympics would lead to reductions in urinary amino-PAHs in Beijing residents. It is also to examine whether amino-PAHs would be associated with traffic-related pollutants measured 1 to 7 days prior to urine collection Methods: Urine samples of 125 healthy and non-smoking subjects were collected before, during, and after the Olympics. PM2.5, EC, CO, NO2, particle number concentrations, and particulate-bound PAHs, were measured throughout the study period. Sum of 1- and 2-Amino-naphthalene and 1-amino-pyrene were measured using an HPLC-fluorescence method. The association between each urinary metabolite and each air pollutant was analyzed using a linear mixed model. Results: The concentrations of each urinary metabolite decreased from the pre- to during-Olympic period, and the decreases in 1&2-Amino-naphthalene were statistically significant. Concentrations of 1&2-amino-naphthalene were consistently and significantly associated with each of PM2.5, EC, NO2, CO, pyrene and benzo(a)pyrine at lag 2. 1-Amino-pyrene was significantly associated with PM2.5, pyrene, and benzo(a)pyrene at lag 1 or 2. Each urinary metabolite was significantly associated with the particle number concentrations at lag 2. Conclusions: Urinary 1&2-Amino-naphthalene and 1-Amino-pyrene may serve as internal dose markers of short-term exposures to traffic-emitted pollutants in urban residents.