典型饮水系统中人工甜味剂三氯蔗糖的调查

Investigation of artificial sweetener sucralose in typical drinking water systems

采用固相萃取-气相色谱/质谱法(SPE-GC/MS)实现水环境中微量三氯蔗糖的准确检测,以浙江省2座城市为主要调查对象,获取自生活污水厂、水源、饮用水处理工艺至终端供水管网用水全循环过程中三氯蔗糖的污染信息;考察饮用水常规及深度处理工艺单元中三氯蔗糖的存在水平及变化规律,评价工艺对三氯蔗糖的控制能力.结果表明,三氯蔗糖在制水及供水系统中的检出率为100%,在水源水、经常规处理后的出水、经臭氧-活性炭深度处理后的水中的质量浓度分别为69.2~2070.1、538.1~856.9、177.7~357.9 ng/L,深度处理工艺控制三氯蔗糖的效果较常规工艺略好,但仍无法实现彻底去除.生活污水中三氯蔗糖的初始质量浓度较水源水中高,为1033.4~2626.3 ng/L,生物处理效果不佳,出水中的质量浓度为917.6~2031.2 ng/L,大部分通过排放进入接纳水体.在持续排放导致入流质量浓度增长指数高于环境降解速率的条件下,三氯蔗糖在水体中可能产生浓度累积效应.

Solid phase extraction-gas chromatography/mass spectrometry(SPE-GC/MS)was employed for accurate detection of micro sucralose in aqueous system.The pollution information of sucralose in a water cycle,including sanitary sewage,water source,potable water treatment process and terminal water supply network,was obtained,with two cities in Zhejiang Province as the main investigation object.The variation of sucralose in the conventional and the advanced water treatment units was investigated and the control ability of treatment process was evaluated.Results showed that the detection rate of sucralose was 100%in water production and water supply systems.The mass concentration values of sucralose in the source water,water after conventional treatment process and water after ozone-activated carbon advanced treatment process were 69.2~2070.1,538.1~856.9,177.7~357.9 ng/L,respectively.Advance treatment process was more effective for sucralose removal than conventional treatment,but was still unable to achieve complete removal.The initial mass concentration of sucralose in the sewage water was1033.4~2626.3 ng/L,much higher than that in the source water.The biological process can not deal with sucralose effectively,and sucralose mass concentration in the emission water remained 917.6~2031.2 ng/L,with most sucralose discharged into the receiving water body.Under the continuous discharge condition,if the increase rate of inflow mass concentration is higher than the environmental degradation rate,sucralose accumulation in the waterbody may occur.