Laboratório de Ecologia de Manguezal (LAMA), Instituto de Estudos Costeiros (IECOS), Universidade Federal do Pará (UFPA), Bragança 68600-000, PA, Brazil.
Grupo de Pesquisa em Ciência e Engenharia de Meios Porosos (GCEMP), Universidade Federal do Pará (UFPA), Salinópolis 68721-000, PA, Brazil.
J Environ Manage. 2024 Aug;366:121826. doi: 10.1016/j.jenvman.2024.121826. Epub 2024 Jul 14.
Pollution by microplastics (MPs) in mangroves is a growing concern, given its potential ecological and human health impacts. The characteristics of microplastic pollution and a risk assessment of MPs in the Amazon region's coastal sediments are still insufficient, and information about MP pollution in the benthic component of the mangrove ecosystem is lacking. We analyzed MP concentrations in the surface sediment of 9 stations in three tidal channels along the Ajuruteua Peninsula connected to the Caeté River estuary, aiming to assess the hazard level on the environment based on the Pollution Load Index (PLI). Raman and Fourier transform infrared spectroscopy determined the MP's chemical composition. The results showed that the abundance of sediment MPs ranged from 100 to 1200 items kg, with an average of 433 ± 261.6 items kg. The MPs were mainly composed of transparent and blue fragments and fibers, ranging in size from 100 to 5000 μm. Six types of polymers were identified, including alkyd varnish (AV), resin dispersion (RD), chlorinated polyethylene (CPE), polyethylene-polypropylene (PE-PP), low-density polyethylene (LDPE), and hostaperm blue (HB). Hydrodynamic processes within estuaries and tidal channels play a crucial role in explaining the concentrations found, as circulation determines the pattern of sediment deposition and the particles adhered to it. PLI risk assessment showed that all sampling sites were at hazard level I: a low level of contamination in the mangrove sediments. However, a more comprehensive and systematic monitoring campaign is needed to expand our knowledge about pollution and contamination by MPs in Amazon mangrove areas.
微塑料（MPs）在红树林中的污染是一个日益严重的问题，因为它可能对生态和人类健康造成影响。亚马逊地区沿海沉积物中微塑料污染的特征和风险评估仍然不足，而且缺乏关于红树林生态系统底栖部分中 MP 污染的信息。我们分析了连接到 Caeté 河口的 Ajuruteua 半岛三个潮汐通道的 9 个站点的表层沉积物中的 MPs 浓度，旨在根据污染负荷指数（PLI）评估环境的危害水平。拉曼和傅里叶变换红外光谱确定了 MPs 的化学成分。结果表明，沉积物中 MPs 的丰度范围为 100 至 1200 项 kg，平均为 433 ± 261.6 项 kg。MPs 主要由透明和蓝色碎片和纤维组成，尺寸范围为 100 至 5000 μm。鉴定出六种类型的聚合物，包括醇酸清漆（AV）、树脂分散体（RD）、氯化聚乙烯（CPE）、聚乙烯-聚丙烯（PE-PP）、低密度聚乙烯（LDPE）和 Hostaperm 蓝（HB）。河口和潮汐通道内的水动力过程在解释所发现的浓度方面起着至关重要的作用，因为环流决定了沉积物沉积的模式和附着在其上的颗粒。PLI 风险评估表明，所有采样点均处于危害水平 I：红树林沉积物的污染程度较低。然而，需要进行更全面和系统的监测活动，以扩大我们对亚马逊红树林地区 MPs 污染和污染的认识。
