Microplastics, as emerging pollutant, are predicted to act as carriers for organic pollutants, but the carrier role and bio-toxic effects with other pollutants in environments are poorly acknowledged. In this study, both the single and combined effects of polyethylene (PE, 10 and 40 mg/L) with the particle size of 100–150 μm and 9-Nitroanthracene (9-NAnt, 5 and 500 μg/L) on zebrafish (Danio rerio) had been investigated. The results illustrated that PE could be as 9-NAnt carrier to enter into zebrafish body, but significantly reduced the bioaccumulation of 9-NAnt, due to the occurrence of adsorption interactions between the simultaneous presence of both PE and 9-NAnt. After 4 days, the enzymes activity of cytochrome P4501A, acetylcholinesterase (AChE), superoxide dismutase (SOD), catalase (CAT), lactate dehydrogenase (LDH), and the abundance of malondialdehyde (MDA), lipid peroxide (LPO) responded strongly to low-dose PE exposure (10 mg/L). After 7 days exposure to PE-9-NAnt (40 mg/L), the P4501A activity increased significantly, but the activities of AChE and LDH were inhibited clearly, causing certain neurotoxicity and disorders of energy metabolism to zebrafish. The analysis of integrated biomarker response index (IBR) suggested that PE had greater bio-toxicity to zebrafish in all exposure groups after short-term exposure, but the PE-9-NAnt complex showed greater bio-toxicity after 7 days, which indicated that complex exposure of PE-9-NAnt had a delayed effect on the bio-toxicity of zebrafish. Furthermore, analysis of the intestinal microbiota exhibited that under the conditions of the exposure group with 9-NAnt, the relative abundance of the five dominant bacterial phyla (Proteobacteria, Firmicutes, Fusobacteriota, Bacteroidota and Verrucomicrobiota) changed greatly. Overall, this study confirmed that PE could carry 9-NAnt into fish causing bioaccumulation, but in the case of coexisting exposures, PE reduced 9-NAnt bioaccumulation, suggesting that microplastics with other emerging pollutants in chronic toxicity are probably next objects in future works.

预计作为新兴污染物的微塑料将作为有机污染物的载体，但是人们对这种载体在环境中的作用以及与其他污染物的生物毒性作用知之甚少。在这项研究中，粒径为100–150μm的聚乙烯（PE，10和40 mg / L）和9-硝基蒽（9-NAnt，5和500μg/ L）对斑马鱼的单一和联合作用（达尼奥·雷里奥（Danio rerio））已被调查。结果表明，PE可以作为9-NAnt载体进入斑马鱼体内，但由于同时存在PE和9-NAnt之间发生吸附相互作用，因此9-NAnt的生物蓄积性显着降低。4天后，细胞色素P4501A，乙酰胆碱酯酶（AChE），超氧化物歧化酶（SOD），过氧化氢酶（CAT），乳酸脱氢酶（LDH）和丰富的丙二醛（MDA），脂质过氧化物（LPO）的酶活性强烈响应低剂量PE暴露（10 mg / L）。暴露于PE-9-NAnt（40 mg / L）7天后，P4501A活性显着增加，但AChE和LDH的活性受到明显抑制，对斑马鱼造成一定的神经毒性和能量代谢紊乱。综合生物标志物反应指数（IBR）的分析表明，短期暴露后，PE在所有暴露组中对斑马鱼都有更大的生物毒性，但PE-9-NAnt复合物在7天后显示出更大的生物毒性，这表明PE-9-NAnt的复杂暴露对斑马鱼的生物毒性具有延迟的影响。此外，对肠道菌群的分析表明，在具有9-NAnt的暴露组的条件下，五个优势细菌菌群（变形杆菌，硬毛菌，梭菌，细菌杆菌和疣状微生物菌群）的相对丰度发生了很大变化。总体而言，这项研究证实了PE可以携带9-NAnt进入鱼类，从而引起生物蓄积，但在暴露并存的情况下，PE可以降低9-NAnt的生物蓄积，