Environmental Studies Laboratory (LEA), Federal University of Ceara, Analytical Chemistry and Physical Chemistry Dpto Campus Pici, Av. Mister Hull, s/n - Pici, CEP 60455-760, Fortaleza, CE, Brazil.
Environmental Studies Laboratory (LEA), Federal University of Ceara, Analytical Chemistry and Physical Chemistry Dpto Campus Pici, Av. Mister Hull, s/n - Pici, CEP 60455-760, Fortaleza, CE, Brazil; National Institute of Science and Technology in Tropical Marine Environments (INCT-AmbTropic, Phase II - Oil Spill), Brazil.
Environ Pollut. 2022 Dec 1;314:120283. doi: 10.1016/j.envpol.2022.120283. Epub 2022 Sep 27.
The main objective of this study was to investigate the 2019 and 2022 oil spill events that occurred off the coast of the State of Ceará, Northeastern Brazil. To further assess these mysterious oil spills, we investigated whether the oils stranded on the beaches of Ceará in 2019 and 2022 had the same origin, whether their compositional differences were due to weathering processes, and whether the materials from both were natural or industrially processed. We collected oil samples in October 2019 and January 2022, soon after their appearance on the beaches. We applied a forensic environmental geochemistry approach using both one-dimensional and two-dimensional gas chromatography to assess chemical composition. The collected material had characteristics of crude oil and not refined oils. In addition, the 2022 oil samples collected over 130 km of the east coast of Ceará had a similar chemical profile and were thus considered to originate from the same source. However, these oils had distinct biomarker profiles compared to those of the 2019 oils, including resistant terpanes and triaromatic steranes, thus excluding the hypothesis that the oil that reached the coast of Ceará in January 2022 is related to the tragedy that occurred in 2019. From a geochemical perspective, the oil released in 2019 is more thermally mature than that released in 2022, with both having source rocks with distinct types of organic matter and depositional environments. As the coast of Ceará has vast ecological diversity and Marine Protected Areas, the possibility of occasional oil spills in the area causing severe environmental pollution should be investigated from multiple perspectives, including forensic environmental geochemistry.
本研究的主要目的是调查 2019 年和 2022 年发生在巴西东北部塞阿拉州沿海的溢油事件。为了进一步评估这些神秘的溢油事件，我们调查了 2019 年和 2022 年滞留在塞阿拉海滩上的油污是否来自同一来源，其组成差异是否归因于风化过程，以及这些物质是否来自天然或工业加工。我们在 2019 年和 2022 年这些溢油事件发生后不久的 10 月和 1 月分别收集了溢油样本。我们应用了一种法医环境地球化学方法，使用一维和二维气相色谱法来评估化学组成。收集到的物质具有原油的特征，而不是精炼油。此外，在塞阿拉东海岸 130 多公里长的范围内采集的 2022 年溢油样本具有相似的化学特征，因此被认为来自同一来源。然而，与 2019 年的溢油相比，这些油具有不同的生物标志物特征，包括抗萜烷和三芳甾烷，因此排除了 2022 年 1 月到达塞阿拉海岸的石油与 2019 年发生的悲剧有关的假设。从地球化学的角度来看，2019 年释放的石油比 2022 年释放的石油热成熟度更高，两者的源岩都具有不同类型的有机质和沉积环境。由于塞阿拉海岸拥有广泛的生态多样性和海洋保护区，应该从多个角度，包括法医环境地球化学，调查该地区偶尔发生的溢油事件对环境造成严重污染的可能性。
