Campos Juan Martins de, Wintruff Larissa Tais Traldi, Souza-Bastos Luciana Rodrigues de, Dal Pont Giorgi, Dolatto Rafael Garrett, Westphal Gisela Geraldine Castilho, Grassi Marco Tadeu, Ostrensky Antonio, Sadauskas-Henrique Helen
Laboratório de Ecofisiologia e Bioquímica de Organismos Aquáticos, Universidade Santa Cecília, Rua Oswaldo Cruz, n. 277 - Boqueirão, Santos, SP 11045-907, Brazil.
Laboratório de Toxicologia e Avaliação Ambiental, Instituto de Tecnologia para o Desenvolvimento - LACTEC, Rodovia BR-116, km 98, n. 8813 - Jardim das Américas, Curitiba, PR 81531-980, Brazil.
Aquat Toxicol. 2023 Oct;263:106693. doi: 10.1016/j.aquatox.2023.106693. Epub 2023 Sep 9.
Microplastic (MP) pollution poses a significant environmental threat. These MPs can adsorb toxic compounds such as polycyclic aromatic hydrocarbons (PAH), which are highly lipophilic and carcinogenic. To assess the potential effects of virgin MP, PAH, and MP+PAH in association with osmoregulation and energetic substrate, we conducted experiments with the tetra cardinal Astyanax lacustris. The environmentally relevant concentration of MP (10 mg L) and 20 % of the LC-96 h of crude oil for A. lacustris (2.28 µg L) were used during the 96-h exposure. Fish were exposed to virgin MP, PAH, MPC (MP loaded with PAH), PAH+MP (PAH and MP in association), and the control without (CT) and with handling (CH). After 96 h, blood was collected for osmoregulatory parameters (plasma osmolality; Na, K, Cl, Mg; glycose and lactate); gills for osmoregulatory enzyme activities (Na, K ATPase, H ATPase, and carbonic anhydrase); and white muscle samples were used to determine glycogen as an energetic substrate. The low molecular weight PAH was not detected in PAH-loaded MP (MPC) and PAH in combination with MP (PAH+MP). The PAH concentration of the MPC and PAH+MP was similar and low compared to other works. Virgin MP, PAH, MPC, and PAH+MP were able to cause muscle glycogen depletion. The activity of v-type H ATPase and plasma Na concentrations were lower in PAH with MP (MPC). However, the hydromineral balance (K, Mg, Cl and osmolality) was not affected by any treatment. In this sense, we can conclude that the MPC caused osmoregulatory disturbances not seen in the MP associated with PAH (MP+PAH). However, this seems unrelated to the PAH leaking from the MPC or the PAH absorption to the virgin MP once the PAH concentrations from the MPC and PAH+MP were similar.
微塑料（MP）污染对环境构成了重大威胁。这些微塑料能够吸附多环芳烃（PAH）等有毒化合物，多环芳烃具有高度亲脂性且具有致癌性。为了评估原始微塑料、多环芳烃以及微塑料与多环芳烃混合物（MP+PAH）对渗透调节和能量底物的潜在影响，我们使用四眼阿氏丽脂鲤进行了实验。在96小时的暴露实验中，采用了与环境相关的微塑料浓度（10毫克/升）以及阿氏丽脂鲤96小时半数致死浓度（LC-96h）的20%的原油浓度（2.28微克/升）。将鱼暴露于原始微塑料、多环芳烃、载有多环芳烃的微塑料（MPC）、多环芳烃与微塑料混合物（PAH+MP）以及无处理对照组（CT）和有处理对照组（CH）。96小时后，采集血液用于检测渗透调节参数（血浆渗透压；钠、钾、氯、镁；葡萄糖和乳酸）；采集鳃用于检测渗透调节酶活性（钠钾ATP酶、氢ATP酶和碳酸酐酶）；采集白色肌肉样本用于测定糖原作为能量底物。在载有多环芳烃的微塑料（MPC）以及多环芳烃与微塑料混合物（PAH+MP）中未检测到低分子量多环芳烃。与其他研究相比，MPC和PAH+MP中的多环芳烃浓度相似且较低。原始微塑料、多环芳烃、MPC和PAH+MP均能导致肌肉糖原消耗。在多环芳烃与微塑料混合物（MPC）中，v型氢ATP酶活性和血浆钠浓度较低。然而，任何处理均未影响水盐平衡（钾、镁、氯和渗透压）。从这个意义上讲，我们可以得出结论，MPC导致了在多环芳烃与微塑料混合物（PAH+MP）中未观察到的渗透调节紊乱。然而，这似乎与MPC中多环芳烃的泄漏或原始微塑料对多环芳烃的吸收无关，因为MPC和PAH+MP中的多环芳烃浓度相似。
