TY - JOUR
T1 - Beyond Substituted p-Phenylenediamine Antioxidants: Prevalence of Their Quinone Derivatives in PM2.5
AU - Wang, Wei
AU - Cao, Guodong
AU - Zhang, Jing
AU - Wu, Pengfei
AU - Chen, Yanyan
AU - Chen, Zhifeng
AU - Qi, Zenghua
AU - Li, Ruijin
AU - Dong, Chuan
AU - Cai, Zongwei
N1 - Funding information:
The corresponding author would like to thank the Kwok Chung Bo Fun Charitable Fund for the establishment of Kwok Yat Wai Endowed Chair of Environmental and Biological Analysis.
Publisher copyright:
© 2022 American Chemical Society
PY - 2022/8/2
Y1 - 2022/8/2
N2 - Substituted para-phenylenediamine (PPD) antioxidants have been extensively used to retard oxidative degradation of tire rubber and were found to pervade multiple environmental compartments. However, there is a paucity of research on the environmental occurrences of their transformation products. In this study, we revealed the co-occurrence of six PPD-derived quinones (PPD-Qs) along with eight PPDs in fine particulate matter (PM2.5) from two Chinese megacities, in which N,N′-bis(1,4-dimethylpentyl)-p-phenylenediamine quinone (77PD-Q) was identified and quantified for the first time. Prevalent occurrences of these emerging PPD-Qs were found in Taiyuan (5.59–8480 pg/m3) and Guangzhou (3.61–4490 pg/m3). Significantly higher levels of PPDs/PPD-Qs were observed at a roadside site, implying the possible contribution of vehicle emissions. Correlation analysis implied potential consistencies in the fate of these PPD-Qs and suggested that most of them were originated from the transformation of their parent PPDs. For different subpopulation groups under different exposure scenarios, the estimated daily intakes of PPD-Qs (0.16–1.25 ng kgbw–1 day–1) were comparable to those of their parent PPDs (0.19–1.41 ng kgbw–1 day–1), suggesting an important but overlooked exposure caused by novel PPD-Qs. Given the prolonged exposure of these antioxidants and their quinone derivatives to traffic-relevant occupations, further investigations on their toxicological and epidemiological effects are necessary.
AB - Substituted para-phenylenediamine (PPD) antioxidants have been extensively used to retard oxidative degradation of tire rubber and were found to pervade multiple environmental compartments. However, there is a paucity of research on the environmental occurrences of their transformation products. In this study, we revealed the co-occurrence of six PPD-derived quinones (PPD-Qs) along with eight PPDs in fine particulate matter (PM2.5) from two Chinese megacities, in which N,N′-bis(1,4-dimethylpentyl)-p-phenylenediamine quinone (77PD-Q) was identified and quantified for the first time. Prevalent occurrences of these emerging PPD-Qs were found in Taiyuan (5.59–8480 pg/m3) and Guangzhou (3.61–4490 pg/m3). Significantly higher levels of PPDs/PPD-Qs were observed at a roadside site, implying the possible contribution of vehicle emissions. Correlation analysis implied potential consistencies in the fate of these PPD-Qs and suggested that most of them were originated from the transformation of their parent PPDs. For different subpopulation groups under different exposure scenarios, the estimated daily intakes of PPD-Qs (0.16–1.25 ng kgbw–1 day–1) were comparable to those of their parent PPDs (0.19–1.41 ng kgbw–1 day–1), suggesting an important but overlooked exposure caused by novel PPD-Qs. Given the prolonged exposure of these antioxidants and their quinone derivatives to traffic-relevant occupations, further investigations on their toxicological and epidemiological effects are necessary.
KW - airborne quinones
KW - fine particulate matter
KW - human inhalation exposure
KW - para-phenylenediamine derivatives
KW - tire rubber additives
UR - http://www.scopus.com/inward/record.url?scp=85135501328&partnerID=8YFLogxK
U2 - 10.1021/acs.est.2c02463
DO - 10.1021/acs.est.2c02463
M3 - Article
VL - 56
SP - 10629
EP - 10637
JO - Environmental Science & Technology
JF - Environmental Science & Technology
SN - 0013-936X
IS - 15
ER -