生态与农村环境学报 ›› 2015, Vol. 31 ›› Issue (6): 866-875.doi: 10.11934/j.issn.1673-4831.2015.06.011

• 区域环境与发展 • 上一篇    下一篇

我国表层土壤多环芳烃(PAHs)污染状况及来源浅析

邓绍坡,吴运金,龙涛,林玉锁,祝欣   

  1. 环境保护部南京环境科学研究所
  • 收稿日期:2015-04-09 修回日期:2015-10-13 出版日期:2015-11-25 发布日期:2015-11-26
  • 通讯作者: 祝欣 E-mail:zhuxin@nies.org
  • 作者简介:邓绍坡(1981—),男,河南洛阳人,助理研究员,博士,主要研究方向为污染场地调查与健康风险评估。E-mail: dsp@nies.org
  • 基金资助:

    2014年中央级公益性科研院所基本科研业务专项

PAHs Contamination in the Surface Soil of China and Its Sources.

DENG Shao-po,WU Yun-jin,LONG Tao,LIN Yu-suo,ZHU Xin   

  1. Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection
  • Received:2015-04-09 Revised:2015-10-13 Online:2015-11-25 Published:2015-11-26

摘要:

统计了2004—2007年间公开发表文献中我国表层(0~30 cm)土壤中美国环保署规定的16种优先控制PAHs含量调查数据,总计约41项研究,包括34个市(地)区的2 353个样点,以研究区域的地理位置划分为东北地区、京津及周围地区、长三角地区、珠三角地区和中西南地区5大区域。从全国范围看,我国浅层土壤中PAHs总量范围为ND(未检出)~27 580.9 μg·kg-1,平均值为1 462.55 μg·kg-1;7种致癌PAHs含量范围为ND~3 657.67 μg·kg-1,平均值为636.64 μg·kg-1,约占PAHs总量的44%。全国2~3环PAHs、4环PAHs和≥5环PAHs所占比例相当。区域间PAHs含量差异较大,处于北方的东北地区、京津及周围地区以及处于南北过渡区的长三角地区表层土壤中PAHs类型主要为4环和≥5环PAHs,代表性单体PAH也多为致癌PAH,处于南方的珠三角地区和中西南地区表层土壤中PAHs主要类型包括2~3环PAHs,代表性单体PAH较少为致癌PAH。利用特征化合物比例法〔Ant/178、Baa/228、Ilp/(Ilp+Bpe)和Fla/(Fla+Pyr)〕对PAHs来源进行分析,结果表明我国表层土壤中PAHs来源以草、木材和煤燃烧为主,汽车尾气排放及石油源也占相当比例;Ilp/(Ilp+Bpe)与Fla/(Fla+Pyr)比值分析表明,京津及周围地区表层土壤中PAHs来源绝大部分以草、木和煤燃烧为主,而长三角和珠三角地区PAHs来源以汽车尾气排放所占比例较大。从PAHs总量来看,我国有23%的土壤未受PAHs污染,轻微污染土壤占31%,污染土壤占8%,严重污染土壤占38%;根据Bap指标进行的评价结果表明,我国有20%的土壤受到污染。2种评估结果均表明北方受污染土壤样点比例要明显高于南方。

关键词: PAHs, 表层土壤, 区域, 特征化合物比例, 来源

Abstract:

Statistics was performed of the data published in the literature during the years of 2004-2007, of the survey of the 16 kinds of PAHs, specified by the US  EPA for priority control, in the surface soil (0-30 cm) of China. The survey encompassed a total of 41 research projects and 2 353 sampling sites, covering 34 cities (or prefectures). According to the geographic locations, the research area was divided into five regions: the northeast region, JingJin and its surrounding region, Yangtse Delta region, Zhujiang Delta region and Midsouthwest region. On the countrywide scale, the amount of total PAHs in the surface soil varied in the range from ND (not detected) to 27 580.9 μg·kg-1, with mean value being 1 462.55 μg·kg-1. The contents of 7 carcinogenic PAHs varied in the range from ND to 3 657.67 μg·kg-1  with mean value being 636.44 μg·kg-1, which accounted for 44% of the total of the 16 PAHs. On the country wide scale, the proportions of 2-3ringed PAHs, 4ringed PAHs and ≥5 ringed PAHs to the total of PAHs were more or less the same. But the regions varied sharply in content of PAHs. The PAHs in the surface soil of the northeast region, and the JingJin and its surrounding region, both of which are located in North China, and the Yangtse Delta region, which lies in the transition from South to North China, were dominated with 4 ringed and ≥5 ringed PAHs, of which most representative individuals were carcinogenic, while those in the Zhujiang Delta region and the Mid southwest region, which are located in South China, were with 2-3ringed PAHs, of which few representative individuals were carcinogenic. Analysis using the character istic compounds ratio method [Ant/178, Baa/228, Ilp/(Ilp+Bpe) and Fla/(Fla+Pyr)] shows that the PAHs in the surface soil of China come mainly from combustion of grasses, woods and coal, and also from vehicle exhaust and petrol industry, accounting for a comparable proportion. The Ilp/(Ilp+Bpe) and Fla/(Fla+Pyr) ratio analysis reveals that in the JingJin region, the PAHs in the surface soil came mostly from combustion of grasses, woods and coal, while in the Yangtse Delta and the Zhujiang Delta regions they did by a large proportion from vehicle exhaust. In terms of total PAHs in soil, 23% of the soil in the country was not contaminated, 31% little contaminated, 8% contaminated and 38% heavily contaminated. However, the evaluation based on Bap indices indicates that about 20% of the soils in the country was contaminated. Whatever, the two assessments both demonstrate that the proportion of PAHs contaminated soils was obviously higher in North China than in South China.

Key words: PAHs, surface soil, region, ratio of characteristic-compound, source