Pollution characteristics and health risk assessments of four phthalate esters in PM_2.5 during heating and non-heating periods in Chaoyang District of Beijing

Objective To understand the pollution characteristics of phthalate esters(PAEs) in PM_2.5 during heating and non-heating periods in Chaoyang District of Beijing and to assess their health risks.

Methods A high-flow sampler combined with glass fiber filter were used to collect PM_2.5 samples during heating and non-heating periods in Chaoyang District of Beijing, the concentration levels of butylbenzyl phthalate (BBP), dibutyl phthalate (DBP), diisobutyl phthalate (DiBP), and diisononyl phthalate (DiNP) in samples were analyzed by GC-Orbitrap-MS.

Results Four kinds of targeted PAEs were detected in different degrees, among which DiBP and DBP had the highest detection rate of 100%. The average concentration of Σ₄PAEs in PM_2.5 during heating period was 143.07 ng/m³, which was 16.5 times higher than that of non-heating period. The monomer contents of PM_2.5 in heating period were ranked as DiBP > DBP > BBP > DiNP, and DiBP > DBP > DiNP > BBP in non-heating period. Σ₄PAEs concentration was positively correlated with PM_2.5 concentration in non-heating period (r_s=0.419, P < 0.05), but there was no significant correlation in heating period. The hazard indexes (HI) of targeted PAEs exposure to adults and children through respiratory pathway were less than 1 in both heating and non-heating periods.

Conclusion Four kinds of targeted PAEs were found in PM_2.5 during heating and non-heating periods in Chaoyang District of Beijing, and their health risks of exposure were acceptable.