Schifter I, González-Macías C, Salazar-Coria L, Sánchez-Reyna G, González-Lozano C
Instituto Mexicano del Petróleo, Dirección de Investigación y Posgrado, Eje Central Lázaro Cárdenas No. 152, San Bartolo Atepehuacan, 07730, México, DF, México.
Environ Monit Assess. 2015 Nov;187(11):723. doi: 10.1007/s10661-015-4944-1. Epub 2015 Oct 30.
Produced water from offshore oil platforms is a major source of oil and related chemicals into the sea. The large volume and high salinity of produced water could pose severe environmental impacts upon inadequate disposal. This study is based on direct field sampling of effluents released into the ocean in the years 2003 and 2013 at the Sonda de Campeche located in the southern part of the Gulf of Mexico. Metals and hydrocarbons were characterized in water, sediments, and fish tissues at the discharge site and compared with those obtained at two reference sites. Chemicals that exceeded risk-based concentrations in the discharge included the metals As, Pb, Cd, and Cr, and a variety of compounds polycyclic aromatic hydrocarbon (PAHs), including naphthalene, fluorenes, and low molecular weight PAHs. The values of low to high molecular weight polycyclic aromatic hydrocarbon (PAHs), and carbon preference index indicate that hydrocarbons in sediments of the discharge zone are originated from the produced water and combustion sources. Fish tissues at the discharge zone and reference site are contaminated with PAHs, dominated by 2- and 3-rings; 4-ring accounted for less than 1% of total PAHs (TPAHs) in 2003, but increased to 7% in 2013. Results suggest that, from 2003 to 2013, discharges of produced water have had a non-negligible impact on ecosystems at a regional level, so the possibility of subtle, cumulative effects from operational discharges should not be ignored.
海上石油平台产生的废水是海洋中石油及相关化学物质的主要来源。废水的大量排放和高盐度如果处理不当，可能会对环境造成严重影响。本研究基于2003年和2013年在墨西哥湾南部坎佩切海槽对排入海洋的废水进行的直接现场采样。对排放点的水、沉积物和鱼类组织中的金属和碳氢化合物进行了特征分析，并与在两个参考点获得的结果进行了比较。排放物中超过基于风险浓度的化学物质包括金属砷、铅、镉和铬，以及多种多环芳烃（PAHs）化合物，包括萘、芴和低分子量多环芳烃。低到高分子量多环芳烃（PAHs）的值以及碳偏好指数表明，排放区沉积物中的碳氢化合物源自采出水和燃烧源。排放区和参考点的鱼类组织受到多环芳烃的污染，以2环和3环为主；4环在2003年占总多环芳烃（TPAHs）的比例不到1%，但在2013年增至7%。结果表明，从2003年到2013年，采出水排放对区域生态系统产生了不可忽视的影响，因此作业排放产生的微妙累积效应的可能性不应被忽视。
