东海表层沉积物中邻苯二甲酸酯的分布特征

Occurrence and Distribution Characteristics of Phthalic Acid Esters(PAEs)in Surface Sediments of the East China Sea

邻苯二甲酸酯（PAEs）广泛存在于各种环境介质中,其毒性和持久性已经引起了人们的高度关注。本文采用气相色谱（GC）测定了东海表层沉积物中的4种常见的PAEs（DMP、DEP、DBP和DnOP）,分析了其分布特征及生态风险。东海海域表层沉积物中4种PAEs总量介于180.3~4 897.6ng·g-1 dw（干重）之间,平均浓度为1 435.0ng·g-1,高值区分布在长江口东南、福建沿岸及济州岛西南泥质区的东南部,次高值在浙江沿岸附近。由于调查区域环境的复杂性和特殊性,总PAEs与TOC的相关性比较小。单体PAEs的平均浓度为DBP〉DEP≈DMP〉DnOP,DBP含量最高,为55.6~4 349.5ng·g-1;DnOP含量最低,为0.1~90.1ng·g-1;DEP和DMP含量相当,均值分别为132.5和122.1ng·g-1。DBP、DEP和DMP在长江口处均有高值,其他地区的分布略有差异,可能与长江口处存在工业废水和生活污水的输入有关。生态风险评价表明DMP在部分站位的含量超过华盛顿警戒标准,但仍小于ERL值;DBP在部分站位的含量高于ERL值,具有潜在风险。总之,东海表层沉积物中DEP、DMP和DnOP的污染程度和生态风险处于较低水平,而DBP的污染相对严重,应加以重视。

Phthalic acid esters（PAE）widely exist in various environmental media,its toxicity and stability had aroused much attention.In this work,four kinds of PAES,dimethyl phthalate（DMP）,diethyl phthalate（DEP）,dibutyl phthalate（DBP）and di-n-octyl phthalate（DnOP）,in surface sediments of East China Sea（ECS）were determined by GC-FID.The PAE distribution characteristics and ecological risk were analyzed in ECS.The total concentrations of those four kinds of PAE congeners ranged from 180.3to 4 897.6ng·g-1（dry weight）,with a mean value of 1 435.0ng·g-1.The high concentration values occurred in the southeast of the Yangtze estuary,Fujian coast and southwest of Jeju Island mud area,and the next higher value area was the Zhejiang coast.Because of the complexity of its peculiar hydrologic environment in the survey area,the correlation between total PAEs and TOC was not quite clear.The concentrations of PAEs were in the order of DBP〉DEP≈DMP 〉DnOP.DBP presented the highest averaged concentration with values of 55.6to 4 349.5ng·g-1,and its concentration in most of research areas were over 500ng·g-1.And DnOP showed the lowest concentration of 0.1to 90.1ng·g-1.The concentrations of DEP and DMP were similar with the average values of 132.5and 122.1ng·g-1.DBP,DEP and DMP had high values at Yangtze estuary,And the distribution of other parts was slightly different,which may be caused by the discharge of industrial effluents and domestic sewage.Ecological risk assessment showed that DMP concentrations of some areas were higher than Washington alert standard criteria values,but still lower than ERL level.In some areas of ECS,DBP concentrations exceeded ERL level,suggesting potential ecological risk in these area.Overall,the pollution level and ecological risk of DEP,DMP and DnOP in ECS were still in a relatively low level.But the pollution and ecological risk of DBP was at a relatively high level,to which much attention should be paid.