Characterizations, relationship, and potential sources of outdoor and indoor particulate matter bound polycyclic aromatic hydrocarbons (PAHs) in a community of Tianjin, Northern China

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are among the most toxic air pollutants in China. However, because there are unsubstantial data on indoor and outdoor particulate PAHs, efforts in assessing inhalation exposure and cancer risk to PAHs are limited in China. This study measured 12 individual PAHs in indoor and outdoor environments at 36 homes during the non-heating period and heating period in 2009. Indoor PAH concentrations were comparable with outdoor environments in the non-heating period, but were lower in the heating period. The average indoor/outdoor ratios in both sampling periods were lower than 1, while the ratios in the non-heating period were higher than those in the heating period. Correlation analysis and coefficient of divergence also verified the difference between indoor and outdoor PAHs, which could be caused by high ventilation in the non-heating period. To support this conclusion, linear and robust regressions were used to estimate the infiltration factor to compare outdoor PAHs to indoor PAHs. The calculated infiltration factors obtained by the two models were similar in the non-heating period but varied greatly in the heating period, which may have been caused by the influence of ventilation. Potential sources were distinguished using a diagnostic ratio and a mixture of coal combustion and traffic emission, which are major sources of PAHs. Practical ImplicationsParticulate PAHs distribution characterizations between indoor and outdoor atmosphere should be implemented in some typical cities, communities or houses. This study will fill the gap of characterizations, relationship and potential sources of outdoor and indoor particulate matter bound PAHs in China, which was rarely reported in previous studies. This study is the first attempt to use the methods of linear and robust regression to estimate the infiltration factors of PAHs. Similar methods were applied only on PM in previous studies. The study also testifies the relationship between ventilation and PAHs indoor-outdoor distribution in several statistical methods.

The oxidative capacity of indoor source combustion derived particulate matter and resulting respiratory toxicity

“…These particles from combustion exist in indoor air can increase the potential exposure to the human respiratory system and resulting in cardiopulmonary diseases (Steinvil et al, 2008). Polycyclic aromatic hydrocarbons (PAHs) have been identified as significant carcinogenic compounds in combustion-derived PM2.5, (Han et al, 2015).…”

Particle‐associated polycyclic aromatic hydrocarbons in a representative urban location (indoor‐outdoor) from South Europe: Assessment of potential sources and cancer risk to humans

“…Finally, the influence of both indoor and outdoor emission sources on indoor PAH concentration was estimated in terms of the ratio of indoor‐to‐outdoor (I/O) concentrations …”

An overview of research and development themes in the measurement and occurrences of polyaromatic hydrocarbons in dusts and particulates

“…In particular the PAH in particulate data is used to calculate incremental lifetime cancer risk for the exposed population [104, 107, 119, 125, 126, 140, 141, 149, 150, 157, 160, 161, 176, 190-192, 214, 221, 222, 228-231]. Three pathways for exposure from PAH in particulates are discussed: i) Ingestion [104,141,149,150,176,190,214,220,222,223,[231][232][233][234][235]; ii) Dermal contact [104,141,149,150,176,214,220,222,223,231,233,235]; and iii) Inhalation exposure [105,131,137,141,142,147,152,159,160,177,181,191,193,208,210,213,220,221,…”