Boughattas Iteb, Zitouni Nesrine, Hattab Sabrine, Mkhinini Marouane, Missawi Omayma, Helaoui Sondes, Mokni Moncef, Bousserrhine Noureddine, Banni Mohamed
Laboratory of Agrobiodiversity and Ecotoxicology, Higher Institute of Agronomy Chott-Meriem, Sousse University, Tunisia; Regional Field Crops Research Center of Beja, Tunisia.
Laboratory of Agrobiodiversity and Ecotoxicology, Higher Institute of Agronomy Chott-Meriem, Sousse University, Tunisia.
J Hazard Mater. 2022 Feb 15;424(Pt C):127578. doi: 10.1016/j.jhazmat.2021.127578. Epub 2021 Oct 23.
Given the wide use of plastic and pesticides in agriculture, microplastics (MP) and the herbicide 2,4 dichloro-phenoxy-acetic acid (2-4-D) can be present simultaneously in soil. Nevertheless, little is known about their combined toxicity. In this study, Eisenia andrei was exposed to environmental MP (100 µg kg soil) and 2,4-D (7 mg kg soil) for 7 and 14 days. Bioaccumulation, genotoxicity, oxidative stress and gene expression level were assessed. Results revealed that MP increased 2,4-D bioaccumulation in earthworms. Simultaneous exposure to both these pollutants caused a significant reduction in lysosomal membrane stability (LMS) and an increase in micronuclei (MNi) frequency. Biochemical analysis revealed oxidative alterations in earthworms exposed to all treatments; being very pronounced in earthworms exposed to the mixture in terms of increase in glutathione-S-Transferase (GST), catalase (CAT) and malondialdehydes accumulation (MDA). Furthermore, an up-regulation in cat and gst expression level was recorded in worms exposed to single or mixture treatment, except MP in case of gst. Our data highlight the toxicity of the combined exposure to MP and 2,4-D and afford new insights into the potential ecological risks posed by MP in terrestrial ecosystems.
鉴于塑料和农药在农业中的广泛使用，微塑料（MP）和除草剂2,4-二氯苯氧乙酸（2,4-D）可能同时存在于土壤中。然而，关于它们的联合毒性却知之甚少。在本研究中，将安德爱胜蚓暴露于环境微塑料（100微克/千克土壤）和2,4-D（7毫克/千克土壤）中7天和14天。评估了生物累积、遗传毒性、氧化应激和基因表达水平。结果显示，微塑料增加了蚯蚓体内2,4-D的生物累积。同时暴露于这两种污染物会导致溶酶体膜稳定性（LMS）显著降低，微核（MNi）频率增加。生化分析显示，所有处理组的蚯蚓均出现氧化改变；在暴露于混合物的蚯蚓中，谷胱甘肽-S-转移酶（GST）、过氧化氢酶（CAT）增加以及丙二醛积累（MDA）方面表现得非常明显。此外，在暴露于单一或混合处理的蚯蚓中，cat和gst表达水平上调，但在gst方面，暴露于微塑料的情况除外。我们的数据突出了微塑料和2,4-D联合暴露的毒性，并为微塑料在陆地生态系统中可能造成的生态风险提供了新的见解。
