加油站地下水中甲基叔丁基醚污染特征OACSTPCD

In order to investigate the pollution characteristics of methyl tert-butyl ether(MTBE)in groundwater of gas station,one year system monitoring of MTBE in groundwater around 71 gas stations in 14 administrative regions of Shanghai was conducted.The monitoring results showed that MTBE was generally detected in the groundwater of gas stations in most districts of Shanghai.The detection mass concentration range of MTBE was ND～11 919 μg/L(ND indicated not detected)and the MTBE concentration showed significant difference among various points.The total detection and the over-standard rate of MTBE was 83.1％and 33.8％,respectively.From the first quarter to the fourth quarter,the detection rate and the over-standard rate of MTBE showed an increasing trend,indicating that the pollution level of MTBE in groundwater was gradually increasing.At the same time,MTBE concentration in groundwater was highly positively correlated with petroleum hydrocarbon concentration,indicating that MTBE pollution may be caused by oil leak during storage and use process.The health risk assessment results of 24 MTBE exceeding standard points showed that,from the first quarter to the fourth quarter,the concentration of MTBE had exceeded the health risk threshold for 11 times,probably threatening to human health.The MTBE concentration got close to the critical value for two times,being a warning sign.The risk of MTBE to human health was gradually increasing over time.Also,a risk assessment was conducted on the MTBE concentration in groundwater,and the MTBE risk control value was determined to be 1.9 μg/L.