Teixeira Matheus, Cesar Ricardo, Abessa Denis, Siqueira Celeste, Lourenço Rodrigo, Vezzone Mariana, Fernandes Yan, Koifman Gustavo, Perina Fernando Cesar, Meigikos Dos Anjos Roberto, Polivanov Helena, Castilhos Zuleica
Department of Geology, CCMN-Geosciences Institute, Federal University of Rio de Janeiro, UFRJ, Av. Athos da Silveira Ramos, 274 - Cidade Universitária, Rio de Janeiro, RJ, Brazil.
Department of Geography, CCMN-Geosciences Institute, Federal University of Rio de Janeiro, UFRJ, Av. Athos da Silveira Ramos, 274 - Cidade Universitária, Rio de Janeiro, RJ, Brazil.
Environ Sci Pollut Res Int. 2023 Jan;30(1):184-200. doi: 10.1007/s11356-022-22214-6. Epub 2022 Jul 27.
Urban tropical lagoons are often impacted by eutrophication, metal, and polycyclic aromatic hydrocarbon (PAH) contamination, but the toxicity of their bottom sediments is still poorly investigated in South America. Aiming to contribute to filling this gap, a sediment quality assessment was conducted in the Tijuca Lagoon (Rio de Janeiro, Brazil) using different lines of evidence (LOEs) including sediment characterization, determination of metals and PAHs, and acute toxicity testing with burrowing amphipods (Tiburonella viscana). Mud and organic matter contents played a crucial role in contaminant distribution along the lagoon. The concentrations of PAH were generally low (mean ΣPAH = 795.42 ± 1146.2 ng/g; n = 23), but a contamination hotspot of light PAH compounds was identified. Such PAHs were mainly pyrolytic, probably related to the deposition of atmospheric pollution, although petrogenic compounds also occur in the lagoon. The data indicated the occurrence of geochemical anomalies of Zn, Cu, Pb, and Hg (mean values = 176.9 ± 91.6, 45.1 ± 21.3, 35.2 ± 15.0, 0.1442 ± 0.0893 mg/kg, respectively; n = 23), probably associated with industrial wastes, garbage deposition, urban runoff, and domestic sewage contributions. The mortality of T. viscana was significant for more than 85% of the samples (mean mortality = 70.3 ± 26.0%; n = 23), but it was not significantly correlated with PAH and metal concentrations. On the other side, domestic sewage contributions and eutrophication seem to play a relevant role in sediment toxicity. Actually, the toxicity observed in the tests seems to be due to the simultaneous influence of multiple toxicants and their combined effects on the organisms. Such stressors may include not only metals, PAH, and eutrophication but also chemicals not evaluated in this study, such as hormones, pharmaceuticals and personal care compounds, perfluorocompounds, detergents, and others.
城市热带泻湖常常受到富营养化、金属以及多环芳烃（PAH）污染的影响，但在南美洲，对其底部沉积物的毒性研究仍很不足。为填补这一空白，我们利用不同的证据线（LOEs），包括沉积物特征分析、金属和多环芳烃的测定以及用穴居双壳纲动物（Tiburonella viscana）进行急性毒性测试，对蒂茹卡泻湖（巴西里约热内卢）进行了沉积物质量评估。泥浆和有机物含量在污染物沿泻湖的分布中起着关键作用。多环芳烃的浓度普遍较低（平均ΣPAH = 795.42 ± 1146.2 ng/g；n = 23），但发现了一个轻质多环芳烃化合物的污染热点。这些多环芳烃主要是热解型的，可能与大气污染的沉积有关，不过泻湖中也存在成岩化合物。数据表明锌、铜、铅和汞存在地球化学异常（平均值分别为176.9 ± 91.6、45.1 ± 21.3、35.2 ± 15.0、0.1442 ± 0.0893 mg/kg；n = 23），可能与工业废物、垃圾倾倒、城市径流和生活污水排放有关。超过85%的样本中，T. viscana的死亡率显著（平均死亡率 = 70.3 ± 26.0%；n = 2），但它与多环芳烃和金属浓度没有显著相关性。另一方面，生活污水排放和富营养化似乎在沉积物毒性中起重要作用。实际上，测试中观察到的毒性似乎是由于多种有毒物质的同时影响及其对生物体的综合作用。这些压力源可能不仅包括金属、多环芳烃和富营养化，还包括本研究未评估的化学物质，如激素、药物和个人护理化合物、全氟化合物、洗涤剂等。
