Kuzyk Z A, Stow J P, Burgess N M, Solomon S M, Reimer K J
Environmental Sciences Group, Royal Military College of Canada, P.O. Box 17000 Stn Forces, Kingston ON, Canada, K7K 7B4.
Sci Total Environ. 2005 Dec 1;351-352:264-84. doi: 10.1016/j.scitotenv.2005.04.050. Epub 2005 Aug 8.
Polychlorinated biphenyls (PCBs) were measured in marine sediments and the coastal food web in Saglek Bay, Labrador, to investigate the influence of a local PCB source. Saglek Bay has been the site of a military radar station since the late 1950s and there was PCB-contaminated soil at a beach prior to cleanup in 1997-1999. PCB concentrations in marine sediments during 1997-1999 ranged from 0.24 to 62000 ng/g (dry weight) and decreased exponentially with distance from the contaminated beach. Given this gradient, spatial trends of PCBs in the food web were examined over four zones, according to distance from the contaminated beach: within 1.5 km--zone one, 1.5-4.5 km--zone two, 4.5-7.5 km--zone three, and greater than 7.5 km--zone four. PCB concentrations in a bottom-feeding fish (shorthorn sculpin, Myoxocephalus scorpius), decreased significantly from zone one to zone two, three, four, and distant Labrador reference sites. PCB concentrations in the eggs of a diving seabird (black guillemot, Cepphus grylle) were as high as 48000 ng/g during 1997-1999 and average concentrations in zones one and two were 84 and 13 times higher than in zone four. Marine invertebrates closely reflected the concentrations of PCBs in the associated sediment. In contrast to the benthic-based food web, anadromous arctic char (Salvelinus alpinus) showed no evidence of PCB accumulation from the contaminated sediments. Relatively high PCB concentrations were discovered in some great black-backed gulls (Larus marinus) and ringed seals (Phoca hispida) but appear to relate more to their high trophic level than sampling location. Those species that fed on or near the seabed and had limited foraging ranges were strongly influenced by the local contamination. Total PCB concentrations in the benthic-based food web were significantly higher than background levels for a distance of at least 7.5 km from the contaminated beach. This area is small in the context of widely distributed contamination from long-range transport but the area's high concentrations are comparable to levels associated with adverse effects elsewhere. Our findings should be useful to better assess the environmental impacts of PCB contamination at other coastal sites in the Arctic.
对拉布拉多省萨格勒克湾的海洋沉积物和沿海食物网中的多氯联苯（PCBs）进行了测量，以调查当地多氯联苯来源的影响。自20世纪50年代末以来，萨格勒克湾一直是一个军事雷达站的所在地，在1997 - 1999年清理之前，一个海滩上存在多氯联苯污染的土壤。1997 - 1999年期间，海洋沉积物中的多氯联苯浓度范围为0.24至62000纳克/克（干重），并随着与受污染海滩距离的增加呈指数下降。鉴于这种梯度，根据与受污染海滩的距离，在四个区域内研究了食物网中多氯联苯的空间趋势：距离受污染海滩1.5公里以内——区域一，1.5 - 4.5公里——区域二，4.5 - 7.5公里——区域三，以及大于7.5公里——区域四。一种底栖鱼类（短角杜父鱼，Myoxocephalus scorpius）体内的多氯联苯浓度从区域一到区域二、三、四以及拉布拉多偏远参考地点显著降低。一种潜水海鸟（黑海鸠，Cepphus grylle）卵中的多氯联苯浓度在1997 - 1999年期间高达48000纳克/克，区域一和区域二的平均浓度分别比区域四高84倍和13倍。海洋无脊椎动物紧密反映了相关沉积物中多氯联苯的浓度。与以底栖生物为基础的食物网不同，溯河产卵的北极红点鲑（Salvelinus alpinus）没有显示出从受污染沉积物中积累多氯联苯的迹象。在一些大黑背鸥（Larus marinus）和环斑海豹（Phoca hispida）体内发现了相对较高的多氯联苯浓度，但这似乎更多地与其高营养级有关，而非采样地点。那些在海底或靠近海底觅食且觅食范围有限的物种受到当地污染的强烈影响。在距离受污染海滩至少7.5公里的范围内，以底栖生物为基础的食物网中的多氯联苯总浓度显著高于背景水平。在来自远距离传输造成的广泛污染背景下，这个区域很小，但该区域的高浓度与其他地方与不良影响相关的水平相当。我们的研究结果应有助于更好地评估北极其他沿海地区多氯联苯污染的环境影响。
