河南省部分农田土壤及典型农作物中PAHs的分布特征及生态、健康风险评价

发布时间：2018-06-20 13:20

  本文选题：多环芳烃 + 健康风险　； 参考：《河南师范大学》2015年硕士论文

【摘要】：多环芳烃(Polycyclic aromatic hydrocarbons,PAHs)具有长期残留性、生物蓄积性、高毒性以及致癌、致畸、致突变效应和环境“雌性化”效应,对人类健康和水生生态系统危害巨大,已成为一个倍受关注的全球性环境问题。河南省是我国农业大省,也是我国农产品的主产省份。因此以农田生态系统中土壤和植物中的PAHs为研究对象,揭示土壤中PAHs的污染特征及其影响因素,定量解析土壤中PAHs来源,探索PAHs在农田生态系统中迁移的规律,评价其生态和健康风险。为实现农田安全生产目标,巩固和提升河南省的农业基础地位以及为国家粮食提供安全保障,主要研究结果如下:1、获嘉农田土壤中PAHs含量范围为6.91 ng/g~106 ng/g,平均含量28.6 ng/g,与荷兰农业土壤标准和国内外其他地区土壤中PAHs含量相比,获嘉农田土壤中PAHs污染水平较低;内梅罗综合污染指数表明获嘉农田土壤中PAHs不存在生态风险。土壤中PAHs的组成以2~3环PAHs为主,占PAHs总量的45.4%~56.2%。因子分析/多元线性回归定量解析获嘉农田土壤中PAHs45.3%来自化石燃料燃烧,32.9%来自生物质燃烧,未知污染源贡献21.8%。2、泌阳农田土壤中PAHs含量含量范围为45.0 ng/g~211 ng/g,平均含量为139ng/g,高于获嘉农田土壤中PAHs含量,但低于荷兰农业土壤标准,且与国内外其他地区土壤中PAHs含量相比,污染水平仍较低。内梅罗综合污染指数表明泌阳农田土壤中PAHs不存在生态风险。泌阳农田土壤中PAHs的组成与获嘉农田土壤中PAHs组成类似,均以2~3环PAHs为主,占PAHs总量的76.7%。因子分析/多元线性回归定量解析泌阳农田土壤中48.1%PAHs来自于生物质燃烧和燃煤,37.9%来自机动车,未知污染源贡献14.0%。与相比,泌阳农田土壤中PAHs不存在生态风险。3、小麦不同组织中ΣPAHs含量范围为13.9 ng/g~50.9 ng/g,其含量沿根-秆-籽粒依次降低。玉米不同组织中ΣPAHs含量高于相应小麦组织中PAHs含量,但(除叶外)不同组织中PAHs含量差异不明显。研究地区小麦和玉米中PAHs含量明显低于其他地区植物中PAHs含量。小麦和玉米各组织(除叶外)中PAHs浓度与土壤中PAHs浓度显著相关,小麦与玉米各组织(除叶外)中PAHs来自于土壤中吸收的PAHs。小麦和玉米不同组织(除叶外)中均以2~3环PAHs含量最高,与相应土壤中PAHs组成特征类似。2~4环PAHs含量沿根-秆-籽粒呈逐渐增加表明其更易由土壤中向植物中迁移,而5~6环PAHs相反趋势表明其较难发生迁移;此外,玉米叶中PAHs组成特征与其他组织不同,表明其PAHs来源的不同。小麦根对PAHs的生物富集能力最强,而其籽粒富集能力最弱,而玉米不同组织对PAHs的富集能力差异不明显。且小麦根、玉米根对土壤中PAHs的生物富集与其本身理化性质并不相关。4、运用终生癌症风险增量(ILCRs)模型对获嘉和泌阳农田土壤中的PAHs进行健康风险评价,其致癌风险低于USEPA规定的可接受的致癌风险下限;儿童整体总暴露致癌风险稍高于成人整体暴露致癌风险,口腔和呼吸摄入为PAHs致癌风险的主要暴露途径。获嘉玉米的CRI值最高,值超过了USEPA规定的可接受的致癌风险上限,致癌风险相对较严重。而获嘉小麦和泌阳玉米的CRI值在10-6≤CRI≤10-4之间,不具备严重的致癌风险。
[Abstract]:Polycyclic aromatic hydrocarbons (PAHs) has long residue, bioaccumulation, high toxicity and carcinogenesis, teratogenicity, mutagenicity and environmental "feminization" effect, which have great harm to human health and aquatic ecosystem. It has become a global environmental problem that has become a major concern. Henan province is a major agricultural province in China. It is the main producing province of agricultural products in China. Therefore, taking the PAHs of soil and plant in the farmland ecosystem as the research object, it reveals the pollution characteristics of PAHs in the soil and its influencing factors, quantitatively analyzes the source of PAHs in the soil, explores the law of the migration of PAHs in the farmland ecosystem, and evaluate its ecological and health risks, in order to realize the safe production of farmland. Objective, to consolidate and enhance the basic agricultural status of Henan province and to provide security for national grain. The main results are as follows: 1, the range of PAHs content in farmland soil in Huojia is 6.91 ng/g~106 ng/g, with an average content of 28.6 ng/g. Compared with the agricultural soil standard in Holland and the content of PAHs in the soil in his region, P in Huojia farmland soil The pollution level of AHs was low, and the Nemero comprehensive pollution index showed that there was no ecological risk in the farmland soil of Huojia. The composition of the soil in the soil was 2~3 ring PAHs, and the 45.4%~56.2%. factor analysis / multiple linear regression analysis of total PAHs was a quantitative analysis. The PAHs45.3% from the farmland soil in Huojia was from the combustion of fossil fuels, and 32.9% from the biomass combustion. The contribution of unknown pollution sources 21.8%.2, the content of PAHs content in farmland soil in Biyang is 45 ng/g~211 ng/g, the average content is 139ng/g, higher than the content of PAHs in Huojia farmland soil, but lower than the standard of Holland agricultural soil, and the pollution level is still low compared with the soil PAHs content in other areas. There was no ecological risk in the farmland soil of Biyang. The composition of PAHs in the farmland soil of Biyang was similar to the composition of PAHs in the farmland soil in Huojia, all of which were 2~3 ring PAHs, accounting for the total PAHs total of 76.7%. factor analysis / multiple linear regression analysis. The 48.1%PAHs from Biyang farmland was from biomass combustion and coal combustion, and 37.9% came from motor vehicles. There was no ecological risk.3 in farmland soil PAHs in Biyang, and the content range of sigma PAHs in different tissues of wheat was 13.9 ng/g~50.9 ng/g, and the content of sigma PAHs in different tissues of wheat decreased in turn. The content of sigma PAHs in different maize tissues was higher than that of PAHs in the corresponding wheat tissues, but the PAHs content was poor in different tissues (except leaves). The content of PAHs in wheat and Maize in the study area was significantly lower than the content of PAHs in other plants. The concentration of PAHs in the wheat and maize tissues (except leaves) was significantly correlated with the concentration of PAHs in the soil. The PAHs from the wheat and maize tissues (except leaves) was derived from the PAHs. wheat and different maize tissues (except leaves) in the soil. The content of PAHs in 2~3 ring is the highest, which is similar to the composition of PAHs in the corresponding soil, which is similar to the PAHs content of.2~4 ring along the root - stem - grain, indicating that it is more easily migrated from the soil to the plant, and the opposite trend of 5~6 ring PAHs indicates that it is difficult to migrate. In addition, the characteristics of PAHs composition in maize leaves are different from other tissues, indicating the difference of its PAHs origin. Wheat root has the strongest bioaccumulation ability to PAHs, and its grain enrichment ability is the weakest, but the difference of PAHs enrichment ability of different maize tissues is not obvious. And the bioaccumulation of PAHs in soil is not related to its physical and chemical properties by wheat root and maize root, and.4 is not related to its physical and chemical properties. The lifetime cancer risk increment (ILCRs) model has been used in Huojia and Biyang farmland soil. PAHs in the soil was evaluated for health risk, which was lower than the acceptable cancer risk lower limit prescribed by USEPA; the risk of total exposure to total exposure in children was slightly higher than that of adult exposure risk, and oral and respiratory intake was the main exposure to the risk of PAHs carcinogenesis. The highest CRI value of jiayyu was higher than that of USEPA. The upper limit of the risk of carcinogenesis is relatively serious, and the CRI value of Huojia wheat and Biyang corn is between 10-6 and CRI less than 10-4, and there is no serious carcinogenic risk.
【学位授予单位】：河南师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X53;X173

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相关期刊论文 前2条

1 张天彬;万洪富;杨国义;高原雪;罗薇;;珠江三角洲典型城市农业土壤及蔬菜中的多环芳烃分布[J];环境科学学报;2008年11期

2 秦宁;何伟;王雁;何s標，

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