Agricultural Experiment Station, Wye Research and Education Center, The University of Maryland, Box 169, 21658, Queenstown, Maryland, U.S.A..
Environ Monit Assess. 1992 Jul;22(1):15-38. doi: 10.1007/BF00402653.
This study was designed to: (1) evaluate dibutyltin (DBT) and tributyltin (TBT) bi-weekly in the water column for four months during the peak boating season (June-September, 1989) at seven stations in the Back Creek and Severn River area of Maryland waters of Chesapeake Bay; (2) compare butyltin values from the 1989 study with values obtained from a similar butyltin monitoring study conducted in 1988 (after Maryland TBT legislation) and 1986 (before Maryland TBT legislation); (3) determine the extent of TBT paint use in the Back Creek area by surveying boat owners; (4) determine dissolved copper concentrations from three of the seven stations bi-weekly during the four-month study; and (5) compare dissolved copper concentrations at these stations with previous copper data collected in 1988.Mean four-month DBT concentrations ranged from 10 to 73 ng/L at the seven stations. Highest DBT concentrations occurred at Station 1 in a marina; lowest concentrations occurred at Station 7 in the Severn River. Mean four-month TBT concentrations ranged from 177 ng/L at Station 1 (marina) to 21 ng/L at Station 7 (Severn River). Maximum TBT concentrations of 361 and 570 ng/L occurred at marina SDtations 1 and 3, respectively. Temporal trends in both DBT and TBT (station mean concentrations by date) showed that peak concentrations occurred during the early part of the boating season followed by reductions in late summer and early fall. Spike concentrations of both DBT (117 and 62 ng/L) and TBT (308 and 366 ng/L) were reported on two sampling dates near a boat maintenance facility in Back Creek.There was a significant reduction in DBT concentrations from 1986 to 1989 when date was treated as a fixed effect. However, TBT concentrations were not significantly reduced between 1986 and 1989 when mean concentrations of TBT were averaged across stations and dates for each year. A significant reduction was reported at Station 1 (marina station) when each station was examined for differences between years. TBT was also reported to significantly decrease (p=0.0442) at Station 7 between 1988 and 1989. A boat owner survey in the study area showed that 6% of the recreational boats that were surveyed were painted with TBT paint in 1989. This was a significant decrease in TBT paint use from the previous year when 31% of recreational boat owners surveyed used TBT paints.An evaluation of dissolved copper concentrations at three stations in the study area in 1989 showed that mean concentrations from bi-weekly sampling for four months was 10 μg/L at Station 1, 7.8 μg/L at Station 4 and 2.7 μg/L at Station 7. Copper concentrations decreased with distance away from the Back Creek marinas. Copper concentrations at all three stations were significantly lower in 1989 than in 1988.
(1) 在 1989 年 6 月至 9 月（高峰期）每两周在马里兰州切萨皮克湾水域的 Back Creek 和 Severn River 地区的七个地点的水柱中评估二丁基锡（DBT）和三丁基锡（TBT）；(2) 将 1989 年的丁基锡值与 1988 年（在马里兰 TBT 立法后）和 1986 年（在马里兰 TBT 立法前）进行的类似丁基锡监测研究获得的值进行比较；(3) 通过对船主进行调查，确定 Back Creek 地区 TBT 涂料的使用程度；(4) 在四个月的研究期间，每两周在七个地点中的三个地点测量溶解铜浓度；(5) 将这些站点的溶解铜浓度与之前在 1988 年收集的铜数据进行比较。七个站点的平均四个月 DBT 浓度范围为 10 至 73 ng/L。最高的 DBT 浓度出现在 Marina 中的站点 1；最低浓度出现在 Severn River 的站点 7。七个站点的平均四个月 TBT 浓度范围为 177 ng/L（站点 1（码头））至 21 ng/L（站点 7（塞文河））。TBT 的最大浓度为 361 和 570 ng/L，分别发生在码头站点 1 和 3。DBT（117 和 62 ng/L）和 TBT（308 和 366 ng/L）的尖峰浓度分别在 Back Creek 的一个船维修设施附近的两次采样日期报告。在靠近船维修设施的两次采样日期报告了 DBT（117 和 62 ng/L）和 TBT（308 和 366 ng/L）的尖峰浓度。在 1986 年至 1989 年期间，当将日期视为固定效应时，DBT 浓度显着降低。然而，当将 1986 年和 1989 年的 TBT 浓度平均值平均到每个站点和日期时，TBT 浓度并没有显着降低。在每个站点进行检查时，站点 1（码头站）报告了显着降低。还报告说，1988 年至 1989 年期间，站点 7 的 TBT 显着减少（p=0.0442）。研究区域的船主调查显示，在接受调查的娱乐船中，1989 年有 6%涂有 TBT 涂料。与前一年相比，这是 TBT 涂料使用量的显着减少，当时接受调查的 31%的休闲船主使用了 TBT 涂料。对研究区域三个站点的溶解铜浓度进行评估，结果表明，四个月内每两周采样的平均浓度为 10μg/L（站点 1），7.8μg/L（站点 4）和 2.7μg/L（站点 7）。铜浓度随离 Back Creek 码头的距离而降低。三个站点的铜浓度均显着低于 1988 年。
