Road dust contamination by polycyclic aromatic hydrocarbons and their methylated derivatives in northern Vietnam: Concentrations, profiles, emission sources, and risk assessment

Hoang Quoc Anh; Tu Binh Minh; Tri Manh Tran; Shin Takahashi

doi:10.1016/j.envpol.2019.113073

Road dust contamination by polycyclic aromatic hydrocarbons and their methylated derivatives in northern Vietnam: Concentrations, profiles, emission sources, and risk assessment

Environ Pollut. 2019 Nov;254(Pt B):113073. doi: 10.1016/j.envpol.2019.113073. Epub 2019 Aug 17.

Authors

Hoang Quoc Anh¹, Tu Binh Minh², Tri Manh Tran², Shin Takahashi³

Affiliations

¹ Center of Advanced Technology for the Environment (CATE), Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama 790-8566, Japan; The United Graduate School of Agricultural Sciences (UGAS-EU), Ehime University, 3-5-7 Tarumi, Matsuyama 790-8566, Japan; Faculty of Chemistry, VNU University of Science, Vietnam National University, 19 Le Thanh Tong, Hanoi, Viet Nam.
² Faculty of Chemistry, VNU University of Science, Vietnam National University, 19 Le Thanh Tong, Hanoi, Viet Nam.
³ Center of Advanced Technology for the Environment (CATE), Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama 790-8566, Japan. Electronic address: takahashi.shin.mu@ehime-u.ac.jp.

PMID: 31454573
DOI: 10.1016/j.envpol.2019.113073

Abstract

Concentrations of unsubstituted and methylated polycyclic aromatic hydrocarbons (PAHs and Me-PAHs) were examined in road dusts from some representative areas with different land-use types in northern Vietnam, providing updated information about the occurrence, sources, and risks of these pollutants in Southeast Asian region. The Vietnamese road dusts were contaminated with low to moderate levels of PAHs and Me-PAHs as compared to those from other countries in the world. Concentrations of PAHs and Me-PAHs (Σ34PAHs) decreased in the order: urban (median 1800; range 1100-5500) ≈ industrial (1300; 550-10,000) > suburban (450; 310-1300) ≈ rural road dust (330; 210-2300 ng g^-1), suggesting an urban-rural declining trend and effects of urbanization-industrialization processes in PAH emission extent in Vietnam. The profiles and diagnostic ratios of PAHs and Me-PAHs in our samples revealed that these compounds were mainly derived from pyrogenic sources rather than petrogenic sources. Traffic emissions (e.g., vehicle exhaust, tire debris, and possible leaks of fuels, oils, and lubricants) were estimated as principal sources of PAHs and Me-PAHs, especially in the urban and industrial areas. Other pyrogenic sources (e.g., coal, wood, and biomass combustion) were also existed in the industrial, suburban, and rural areas, reflecting PAH origins from thermal industrial processes, open burning of agricultural by-products, and domestic energy utilization. Persons working outdoors and children in the urban and industrial areas were estimated to receive higher intake doses of PAHs and Me-PAHs, which were one to two orders of magnitude higher than those estimated for other groups. Except for potential cancer risk estimated for the occupational groups in the industrial area under the worst exposure scenarios, the non-cancer and cancer risk levels were generally acceptable; however, more comprehensive risk assessment considering other exposure pathways (e.g., inhalation and diet) is needed.

Keywords: Methylated PAHs; PAHs; Risk assessment; Road dust; Urbanization-industrialization processes.

MeSH terms

Agriculture
Biomass
Child
Coal
Dust / analysis
Environmental Monitoring*
Environmental Pollutants / analysis*
Humans
Polycyclic Aromatic Hydrocarbons / analysis*
Risk Assessment
Urbanization
Vehicle Emissions
Vietnam
Wood / chemistry

Substances

Coal
Dust
Environmental Pollutants
Polycyclic Aromatic Hydrocarbons
Vehicle Emissions