North Carolina Cooperative Fish and Wildlife Research Unit, Department of Applied Ecology, North Carolina State University, Campus Box 7617, Raleigh, NC 27695, USA.
Department of Applied Ecology, North Carolina State University, Campus Box 7617, Raleigh, NC 27695, USA.
Environ Res. 2018 Feb;161:615-623. doi: 10.1016/j.envres.2017.11.053.
Environmental contamination is problematic for tropical islands due to their typically dense human populations and competing land and water uses. The Caribbean island of Puerto Rico (USA) has a long history of anthropogenic chemical use, and its human population density is among the highest globally, providing a model environment to study contaminant impacts on tropical island stream ecosystems. Polycyclic Aromatic Hydrocarbons, historic-use chlorinated pesticides, current-use pesticides, Polychlorinated Biphenyls (PCBs), and metals (mercury, cadmium, copper, lead, nickel, zinc, and selenium) were quantified in the habitat and biota of Puerto Rico streams and assessed in relation to land-use patterns and toxicological thresholds. Water, sediment, and native fish and shrimp species were sampled in 13 rivers spanning broad watershed land-use characteristics during 2009-2010. Contrary to expectations, freshwater stream ecosystems in Puerto Rico were not severely polluted, likely due to frequent flushing flows and reduced deposition associated with recurring flood events. Notable exceptions of contamination were nickel in sediment within three agricultural watersheds (range 123-336ppm dry weight) and organic contaminants (PCBs, organochlorine pesticides) and mercury in urban landscapes. At an urban site, PCBs in several fish species (Mountain Mullet Agonostomus monticola [range 0.019-0.030ppm wet weight] and American Eel Anguilla rostrata [0.019-0.031ppm wet weight]) may pose human health hazards, with concentrations exceeding the U.S. Environmental Protection Agency (EPA) consumption limit for 1 meal/month. American Eel at the urban site also contained dieldrin (range < detection-0.024ppm wet weight) that exceeded the EPA maximum allowable consumption limit. The Bigmouth Sleeper Gobiomorous dormitor, an important piscivorus sport fish, accumulated low levels of organic contaminants in edible muscle tissue (due to its low lipid content) and may be most suitable for human consumption island-wide; only mercury at one site (an urban location) exceeded EPA's consumption limit of 3 meals/month for this species. These results comprise the first comprehensive island-wide contaminant assessment of Puerto Rico streams and biota and provide natural resource and public health agencies here and in similar tropical islands elsewhere with information needed to guide ecosystem and fisheries conservation and management and human health risk assessment.
由于热带岛屿通常人口密集，土地和水资源利用竞争激烈，因此环境污染物对这些岛屿造成了问题。波多黎各（美国）是加勒比海的一个岛屿，长期以来一直有人工合成化学品的使用，其人口密度在全球范围内也是最高的，为研究污染物对热带岛屿溪流生态系统的影响提供了一个理想的环境。多环芳烃、历史上使用的氯化农药、当前使用的农药、多氯联苯（PCBs）和金属（汞、镉、铜、铅、镍、锌和硒）在波多黎各溪流的栖息地和生物群中进行了定量分析，并根据土地利用模式和毒理学阈值进行了评估。2009 年至 2010 年期间，在 13 条河流中采集了水、沉积物、本地鱼类和虾类样本，这些河流的流域土地利用特征广泛。与预期相反，波多黎各的淡水溪流生态系统并未受到严重污染，这可能是由于频繁的冲刷水流和与洪水事件相关的沉积减少所致。值得注意的是，在三个农业流域的沉积物中镍含量较高（范围为 123-336ppm 干重），以及在城市景观中的有机污染物（PCBs、有机氯农药）和汞含量较高。在一个城市地区，几种鱼类（山地鲻鱼 Agonostomus monticola [范围 0.019-0.030ppm 湿重] 和美洲鳗 Anguilla rostrata [0.019-0.031ppm 湿重]）中的多氯联苯含量可能对人类健康构成危害，其浓度超过了美国环境保护署（EPA）规定的每月 1 餐的食用限量。在城市地区的美洲鳗体内还含有狄氏剂（范围<检测-0.024ppm 湿重），超过了 EPA 规定的最大允许摄入量。大口睡鲨 Gobiomorus dormitor 是一种重要的肉食性运动鱼类，其可食用肌肉组织中积累的有机污染物水平较低（由于其脂质含量较低），可能最适合在全岛范围内食用；只有在一个地点（城市地区）的汞含量超过了 EPA 对该物种规定的每月 3 餐的食用限量。这些结果构成了对波多黎各溪流和生物群的首次全面岛屿范围的污染物评估，并为这里和其他类似热带岛屿的自然资源和公共卫生机构提供了必要的信息，以指导生态系统和渔业保护和管理以及人类健康风险评估。
