New Directions: Need for better understanding of plastic waste burning as inferred from high abundance of terephthalic acid in South Asian aerosols
New Directions: Need for better understanding of plastic waste burning as inferred from high abundance of terephthalic acid in South Asian aerosols
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DOI：
10.1016/j.atmosenv.2010.09.016
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发表时间：
2010-12
影响因子：
5
通讯作者：
K. Kawamura;C. Pavuluri
中科院分区：
文献类型：
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作者：
K. Kawamura;C. Pavuluri
对苯二甲酸（1，4-benzenedicarboxylic acid; t-Ph）是用于制造塑料如聚酯纤维和PET（聚对苯二甲酸乙二醇酯）热塑性塑料的重要工业材料。在公共卫生方面，t-Ph促进膀胱癌（Heck和Tyl，1985）。2000年，全球塑料消费量达到每年1.5亿吨，年增长率为5.5%（Braun，2004年）。2004年，仅聚酯纤维的全球产量就达到2450万吨（占世界化学纤维市场的65%），其中61%来自亚洲，其次是北美和西欧（Aizenshtein，2006年）。虽然塑料材料在发达国家越来越多地被回收利用，但在发展中国家，它们被作为城市固体废物倾倒。城市固体废物通常在明火条件下燃烧，以避免在垃圾场附近传播疟疾的蚊子传播，向大气中排放塑料分解产物。据报道，在露天焚烧新塑料袋（907 ng mg·kg-1）、路边垃圾（5033 ng mg·kg-1）和垃圾填埋场垃圾（176 ng mg·kg-1）产生的烟雾颗粒中，t-Ph水平升高（Simoneit等人，2005年）。此外，通过大气氧化反应的二次形成也可能是显著的。然而，在并非来自上述露天焚烧活动的环境气溶胶中，很少有关于t-Ph的报告（表1）。我们分析了环境气溶胶样品（PM10）收集的大城市钦奈，印度（13.04 N 80.17 E）的分子分布的二羧酸，使用气相色谱（GC）和GC/质谱。气溶胶取样和分析程序的细节在别处描述（Pavuluri等人，2010年）。简而言之，PM10样本是在印度理工学院马德拉斯校区机械科学大楼的屋顶（离地面18米）收集的。采样位置并不靠近城市生活垃圾焚烧场，而是更典型的城市背景。我们检测到t-Ph非常高的浓度范围从7.6到168 ng m3（平均45 ng m3）在冬季和24-158 ng m3（61 ng m3）在夏季。在大多数样本中，特别是在夜间样本中，发现t-Ph是第二丰富的二羧酸，仅次于草酸（114-696 ng m ³ 3），草酸是来自地球仪许多地方的颗粒物中最丰富的水溶性有机物（例如，Kawamura和Ikushima，1993年）。尽管邻苯二甲酸（Ph）已被报道为全球颗粒中最丰富的芳香族二酸，但Ph和异苯二甲酸（i-Ph）在Chennai气溶胶中是相当次要的异构体（Pavuluri等人，2010年）。金奈气溶胶中的t-Ph浓度是北美和东亚城市气溶胶（TSP）以及西太平洋和南大洋海洋气溶胶（TSP）报告浓度的10倍（表1）。在南亚，特别是印度，城市固体废物的产生量非常高，人均每天0.5-0.7千克（每年48 Tg; 1997年），其中塑料占2- 8%。90%的城市固体废物在没有规定的情况下被处置到开放的垃圾填埋场（Jha等人，2008年），当地居民经常对垃圾进行照明，以避免废物的恶臭和传播疟疾的蚊子的出现。塑料在明火条件下很容易分解成单体。这些单体可以排放到大气中并吸附到预先存在的颗粒上。有趣的是，金奈气溶胶中t-Ph的质量浓度在冬季为55-1620 ng mg/L（平均466 ng mg/L），夏季为305-1890 ng mg/L（764 ng mg/L）。这些值与报告的...
Terephthalic acid (1, 4-benzenedicarboxylic acid; t-Ph) is an important industrial material used for making plastics such as polyester fibre and PET (polyethyleneterephthalate) thermoplastics. In term of public health, t-Ph promotes bladder cancer (Heck and Tyl, 1985). Global consumption of plastics reached 150 million tons per year in 2000, with an annual growth rate of 5.5%(Braun, 2004). Global production of polyester fibre alone was 24.5 million tons (65% of the world chemical fibre market) in 2004, 61% of which comes from Asia, followed by North America and Western Europe (Aizenshtein, 2006). Although plastic materials are increasingly recycled in developed countries, they are dumped as municipal solid wastes (MSW) in developing countries. The MSW are often burned under open-fire conditions to avoid the spread of mosquitoes that transmit malaria near the dumpsite, emitting plastic decomposition products to the atmosphere. t-Ph has been reported at elevated levels in smoke particles derived from open burning of new plastic bags (907 ng mg À1), roadside litter (5033 ng mg À1) and landfill trash (176 ng mg À1)(Simoneit et al., 2005). In addition, secondary formation by atmospheric oxidation reactions may also be significant. However, t-Ph has rarely been reported in ambient aerosols that are not derived from open-burning activities such as those listed above (Table 1). We have analyzed ambient aerosol samples (PM10) collected from the megacity Chennai, India (13.04 N 80.17 E) for molecular distributions of dicarboxylic acids using gas chromatography (GC) and GC/mass spectrometry. The details of the aerosol sampling and analytical procedures are described elsewhere (Pavuluri et al., 2010). Briefly, PM10 samples were collected on the rooftop of the Mechanical Sciences Building (18 m above the ground) at the Indian Institute of Technology Madras campus. The sampling location was not close to a MSW incineration site; rather it is more typical of city background. We detected t-Ph with very high concentrations ranging from 7.6 to 168 ng m À3 (average 45 ng m À3) in winter and 24–158 ng m À3 (61 ng m À3) in summer. t-Ph was found as the second most abundant dicarboxylic acid in most of the samples, in particular in nighttime samples, following oxalic acid (114–696 ng m À3), which is the most abundant water-soluble organic in particles from many locations around the globe (eg, Kawamura and Ikushima, 1993). Although phthalic acid (Ph) has been reported as the most abundant aromatic diacid in particles globally, Ph and isophthalic (i-Ph) acids were rather minor isomers in Chennai aerosols (Pavuluri et al., 2010). t-Ph concentrations in Chennai aerosols are 10 times greater than those reported for urban aerosols (TSP) from North America and East Asia as well as marine aerosols (TSP) from the Western Pacific and Southern Ocean (Table 1). In South Asia, in particular, India, the generation of MSW is very high with a rate of 0.5–0.7 kg capita À1 day À1 (48 Tg per year; 1997), in which plastics account for 2–8%.> 90% of MSW are disposed into open landfills without regulations (Jha et al., 2008), and local residents very often set light to the garbage to avoid the stench from the wastes and the occurrence of mosquitoes that transmit malaria. Plastics may readily decompose into monomers under open-fire conditions. These monomers can be emitted to the atmosphere and adsorbed onto preexisting particles. Interestingly, mass concentrations of t-Ph in Chennai aerosols were 55–1620 ng mg À1 (average 466 ng mg À1) in winter and 305–1890 ng mg À1 (764 ng mg À1) in summer. These values are comparable to those reported for …