Wade Terry L, Sweet Stephen T, Klein Andrew G
Geochemical and Environmental Research Group, Texas A&M University, 833 Graham Road, College Station, TX 77845, USA.
Environ Pollut. 2008 Apr;152(3):505-21. doi: 10.1016/j.envpol.2007.07.016. Epub 2007 Sep 5.
The current status of contaminant concentrations in Casco Bay, decadal trends of these contaminants and changes in their geographical distribution are assessed using sediment samples collected approximately 10 years apart. In general, regulated contaminants appeared to be decreasing in concentration. Total PAH and dioxins/furans concentrations did not significantly change over this period. Total organochlorine pesticides, 4,4-DDE, 4,4-DDD, total DDT, PCB, tributyltin and total butyltin decreased in concentration. Trace element concentrations in sediments decreased at the majority of the sampling sites for chromium, nickel, and selenium while arsenic, cadmium, copper, lead, mercury, silver, and zinc remained relatively constant. None of the contaminants measured has increased by more than a factor of 2. Selected sites located in the Inner Bay, where concentrations are higher and new inputs were more likely, showed increased concentrations of contaminants. Most contaminants were not found at concentrations expected to adversely affect sediment biota based on ERL/ERM guidelines.
利用相隔约10年采集的沉积物样本，评估了卡斯科湾污染物浓度的现状、这些污染物的年代际趋势及其地理分布变化。总体而言，受监管污染物的浓度似乎在下降。在此期间，总多环芳烃和二噁英/呋喃浓度没有显著变化。总有机氯农药、4,4-滴滴伊、4,4-滴滴滴、总滴滴涕、多氯联苯、三丁基锡和总丁基锡的浓度下降。沉积物中铬、镍和硒的微量元素浓度在大多数采样点下降，而砷、镉、铜、铅、汞、银和锌则保持相对稳定。所测量的污染物中没有一种增加超过2倍。位于内湾的选定地点，污染物浓度较高且新输入更有可能，这些地点的污染物浓度有所增加。根据效应浓度低值/效应浓度中值准则，大多数污染物的浓度未达到预期会对沉积物生物群产生不利影响的水平。
