Abstract:
Legacy disposal of oil and gas produced water (OGPW) to surface water has led to radium contamination in streambed sediment creating a long-term radium source. Increased radium activities pose a potential health hazard to benthic organisms, such as freshwater mussels, as radium is capable of bioaccumulation. This project quantifies the impact of OGPW disposal on adult freshwater mussels, Eurynia dilatata, which were examined along the Allegheny River adjacent to a centralized waste treatment facility (CWT) that historically treated and then discharged OGPW. Radium isotopes (226Ra and 228Ra) were measured in streambed sediment, mussel soft tissue, and mussel hard shell collected upstream, at the outfall, 0.5 km downstream, and 5 km downstream of the CWT. Total radium activity was significantly higher (p < 0.05) in mussel tissue (mean = 3.44 ± 0.95 pCi/g), sediment (mean = 1.45 ± 0.19 pCi/g), and hard shell (mean = 0.34 ± 0.11 pCi/g) samples 0.5 km downstream than background samples collected upstream (mean = 1.27 ± 0.24; 0.91 ± 0.09; 0.10 ± 0.02 pCi/g respectively). Mussel shells displayed increased 226Ra activities up to 5 km downstream of the original discharge. Downstream soft tissue and hard shell 87Sr/86Sr ratios, as well as hard shell metal/calcium (e.g., Na/Ca; K/Ca; Mg/Ca) and 228Ra/226Ra ratios demonstrated trends towards values characteristic of Marcellus OGPW. Combined, this study demonstrates multiple lines of evidence for radium retention and bioaccumulation in freshwater mussels resulting from exposure to Marcellus OGPW.
摘要:
将石油和天然气生产的水(OGPW)遗留到地表水中已导致河床沉积物中的镭污染,从而产生了长期的镭源。镭活动的增加对底栖生物构成潜在的健康危害,如淡水贻贝,因为镭能够生物积累。该项目量化了OGPW处置对成年淡水贻贝的影响,Euryniadilatata,沿着阿勒格尼河对其进行了检查,毗邻一个集中式废物处理设施(CWT),该废物处理设施在历史上进行了处理,然后排放了OGPW。在河床沉积物中测量了镭同位素(226Ra和228Ra),贻贝软组织,和上游收集的贻贝硬壳,在出水口,下游0.5km,和CWT下游5公里。贻贝组织中的总镭活性显著高于(p<0.05)(平均值=3.44±0.95pCi/g),沉积物(平均值=1.45±0.19pCi/g),和硬壳(平均值=0.34±0.11pCi/g)样品比上游收集的背景样品下游0.5km(平均值=1.27±0.24;0.91±0.09;0.10±0.02pCi/g)。贻贝贝壳显示出226Ra活动增加,直到原始放电下游5km。下游软组织和硬壳87Sr/86Sr比率,以及硬壳金属/钙(例如,Na/Ca;K/Ca;Mg/Ca)和228Ra/226Ra比率显示出朝着MarcellusOGPW特征值的趋势。合并,这项研究证明了由于暴露于MarcellusOGPW而导致的淡水贻贝中镭保留和生物积累的多种证据。