沈阳地区地表水、浅层地下水及沿岸土壤中苯

对沈阳地区主要地表水(浑河、细河、蒲河、沈抚灌渠)及其沿岸地下水和土壤中苯系物(BTEX)的污染特点和分布特征进行了研究.结果表明:细河和沈抚灌渠地表水中BTEX检出率较高(33%～67%)，苯和甲苯是该区域的主要污染物，ρ(苯)和ρ(甲苯)分别为<0.30～24.90和<0.30～354.00 μg/L；地表水检出的BTEX均未超过《生活饮用水卫生标准》(GB5749—2006)的限值(1 510 μg/L). 细河两岸的浅层地下水在一定程度上受到BTEX的污染，苯和甲苯的检出率分别为25%～33%和13%～25%，二甲苯和乙苯检出率较低(0～20%). 彰驿镇19个监测井中有2个浅层地下水监测井中的ρ(苯)超过GB5749—2006限值(10 μg/L)，夏季ρ(苯)最大值为236.00 μg/L. 沿岸附近土壤中5种BTEX全部被检出，检出率均高于相应的河水. 研究区包气带土壤层虽具有良好的防污性能，但也具有储存和阻碍BTEX挥发和降解的负面效应，对当地的生态系统和人类健康构成了潜在的威胁. 

Contamination Distribution of Benzene, Toluene, Ethylbenzene and Xylene in Surface Water, Shallow Groundwater and the Adjacent Soils from Shenyang Area

Contamination levels and distribution characteristics of benzene, toluene, ethylbenzene and xylene (named BTEX) in surface water, shallow groundwater and the adjacent soils from the Shenyang area were investigated.The detectable rates of BTEX (33%-67%) in water samples from the Xihe River and Shenfu irrigation channel were higher than those measured in water collected from the Hunhe and Puhe Rivers.Benzene and toluene were the dominant contaminants with mass concentration ranges of <0.30-24.90 μg/L and <0.30-354.00 μg/L, respectively.Total mass concentration of BTEX in the surface waters did not exceed the limit value in Standards for Drinking Water Quality (GB5749-2006) (1,510 μg/L).The shallow groundwater near the Xihe River was polluted with BTEX to some extent, with detectable rates of 25%-33% and 13%-25% for benzene and toluene respectively.The detectable rates for ethylbenzene and xylene were low (0-20%).Among 19 shallow groundwater wells studied in Zhangyi Town, mass concentrations of benzene in two wells exceeded the Standards for Drinking Water Quality (GB5749-2006) (10 μg/L).The maximum benzene mass concentration was 236.00 μgL in summer.Five BTEX compounds were all detected in the adjacent soils, and the detectable rates in soils were greater than those measured in corresponding water samples.Aeration zone soils in the studied area showed good pollutant-blockage features, but could hinder volatilization and biodegradation of BTEX in the ground water and pose potential risks to the ecosystem and local human health.