Wang Xinlei, Lv Min, Liu Jin, Ba Mingtao, Man Mingsan, Yin Kun, Ding Jing, Chang Xianbo, Chen Lingxin
School of Environmental and Material Engineering, Yantai University, Yantai 264005, China.
CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; Yantai Key Laboratory of Nuclear Safety Assurance for Marine Ecological Environment, Yantai 264003, China.
Aquat Toxicol. 2025 Feb;279:107257. doi: 10.1016/j.aquatox.2025.107257. Epub 2025 Jan 22.
Antibiotics and microplastics (MPs) are two classes of emerging contaminants that are commonly found in various water environments. However, how different sized MPs affect the toxicity and biodegradation of antibiotics remains poorly understood. We investigated the effects of polystyrene (PS) MPs with different particle sizes (100 nm and 30 μm) on the physiological responses and degradation behavior of Phaeodactylum tricornutum to sulfamerazine (SMR). Results showed that microalgae growth was inhibited by SMR, and MPs especially those of smaller size exacerbated the inhibitory effects of SMR on microalgae, including decreasing the content of chlorophyll a, carotenoids, malondiadehyde and superoxide dismutase activity. MPs exhibited low adsorption towards SMR, and MPs especially 30 μm MPs strengthened SMR photodegradation through leaching more organic chemicals. In comparison, 100 nm MPs obstructed the light, resulting in insignificant effects on photodegradation. Apart from photodegradation, SMR could be bioaccumulated and biodegraded by microalgae, and biodegradation was the main removal mechanism. The overall influence of MPs on SMR degradation by microalgae was a balance of the promotion on photodegradation and negative effects on microalgae growth, with the degradation efficiency and rate of SMR significantly lower in treatment of 100 nm MPs (0.0128 ± 0.0012 day, 30.13 ± 0.36 %) than treatments without MPs (0.0155 ± 0.0011 day, 32.90 ± 3.11 %) or with 30 μm MPs (0.0165 ± 0.0013 day, 34.46 ± 2.52 %). Overall, this study reveals the size-specific effects of MPs on the toxicity and degradation behavior of SMR, providing novel insights into the combined effects of SMR and MPs.
抗生素和微塑料（MPs）是两类常见于各种水环境中的新兴污染物。然而，不同尺寸的微塑料如何影响抗生素的毒性和生物降解仍知之甚少。我们研究了不同粒径（100纳米和30微米）的聚苯乙烯（PS）微塑料对三角褐指藻对磺胺甲嘧啶（SMR）的生理反应和降解行为的影响。结果表明，磺胺甲嘧啶抑制微藻生长，微塑料尤其是较小尺寸的微塑料加剧了磺胺甲嘧啶对微藻的抑制作用，包括降低叶绿素a、类胡萝卜素、丙二醛含量和超氧化物歧化酶活性。微塑料对磺胺甲嘧啶的吸附较低，微塑料尤其是30微米的微塑料通过浸出更多有机化学物质增强了磺胺甲嘧啶的光降解。相比之下，100纳米的微塑料阻挡了光线，对光降解影响不显著。除光降解外，磺胺甲嘧啶可被微藻生物累积和生物降解，生物降解是主要的去除机制。微塑料对微藻降解磺胺甲嘧啶的总体影响是光降解促进作用和对微藻生长负面影响的平衡，100纳米微塑料处理组中磺胺甲嘧啶的降解效率和速率（0.0128±0.0012天，30.13±0.36%）显著低于无微塑料处理组（0.0155±0.0011天，32.90±3.11%）或30微米微塑料处理组（0.0165±0.0013天，34.46±2.52%）。总体而言，本研究揭示了微塑料对磺胺甲嘧啶毒性和降解行为的尺寸特异性影响，为磺胺甲嘧啶和微塑料的联合效应提供了新的见解。
