Tropospheric volatile organic compounds in China

Abstract

Photochemical smog, characterized by high concentrations of ozone (O) and fine particles (PM) in the atmosphere, has become one of the top environmental concerns in China. Volatile organic compounds (VOCs), one of the key precursors of O and secondary organic aerosol (SOA) (an important component of PM), have a critical influence on atmospheric chemistry and subsequently affect regional and global climate. Thus, VOCs have been extensively studied in many cities and regions in China, especially in the North China Plain, the Yangtze River Delta and the Pearl River Delta regions where photochemical smog pollution has become increasingly worse over recent decades. This paper reviews the main studies conducted in China on the characteristics and sources of VOCs, their relationship with O and SOA, and their removal technology. This paper also provides an integrated literature review on the formulation and implementation of effective control strategies of VOCs and photochemical smog, as well as suggestions for future directions of VOCs study in China.

PAN–Precursor Relationship and Process Analysis of PAN Variations in the Pearl River Delta Region

“…In the PRD region, toluene and other aromatics were mainly from vehicular emissions and solvent usage, while xylenes and trimethylbenzene were emitted from solvent usage. On the other hand, isoprene was mainly from biogenic emissions, and C 3 -C 4 alkenes (i.e, propene and butenes) were from vehicular emissions [22,[38][39][40]. For anthropogenic species, the mixing ratios at the BGS site were much lower than the data collected at the downwind rural site in autumn 2007 (the Wanqinsha site) and in autumn 2014 (the Heshan site, unpublished data from Prof. Min Shao, Jinan University), while the mixing ratios of biogenic species and isoprene, between the BGS and Heshan sites, were comparable.…”

“…Note that the measurement data used in the present study were collected in 2006, which may not represent the present atmosphere of PRD, where photochemical products (i.e., O 3 , PAN, and SOA) and their precursors (VOCs and NO x ) have experienced significant variations in the last decade, because of the rapid urbanization/industrialization and considerable control measures implemented in the last decade [19,20]. For example, gross national product (GDP), energy consumption, and developed land area have increased 300%, 160%, and 150%, from 2006 to 2016, respectively [21]; meanwhile, control measures, including laws, standards, regulation, action plans, and others, have been implemented and formulated to alleviate photochemical pollution [22]. Based on the studies of source apportionments of VOCs (vehicle-related emissions), mixed solvents and LPG (liquefied petroleum gas) leakage are considered as the major sources of VOCs in PRD in recent years, with the source contributions varying with the sampling sites, time periods, and types Atmosphere 2018, 9, 372 3 of 16 of VOCs measured [20].…”

Metabolomics analysis reveals that benzo[a]pyrene, a component of PM2.5, promotes pulmonary injury by modifying lipid metabolism in a phospholipase A2-dependent manner in vivo and in vitro

“…With rapid industrialization, haze-fog-associated air pollution, characterized by a high level of particulate matter (PM), has become one of the most severe environmental issues in China [1]. The detrimental effect of PM is mainly determined by its size and composition.…”

Volatile Organic Compounds in a Petrochemical Region in Arid of NW China: Chemical Reactivity and Source Apportionment

“…Volatile organic compounds (VOCs) are important substances in the atmosphere because they can produce ozone and other oxidants via photochemistry and consequently lead to the increase of atmospheric oxidative capacity and the deterioration of air quality [1][2][3][4]. Toxic VOCs (e.g., benzene, toluene, ethylbenzene, and 1,3-butadiene) can stimulate the human respiratory system, damage the nervous system, and increase the risk of cancer [5][6][7][8].…”