Turna Demir Fatma, Akkoyunlu Gökhan, Demir Eşref
Department of Medical Services and Techniques, Medical Laboratory Techniques Programme, Vocational School of Health Services, Antalya Bilim University, 07190 Antalya, Turkey.
Department of Histology and Embryology, Faculty of Medicine, Akdeniz University, 07070 Antalya, Turkey.
Biology (Basel). 2022 Oct 8;11(10):1470. doi: 10.3390/biology11101470.
Living organisms are now constantly exposed to microplastics and nanoplastics (MNPLs), and besides their toxic potential, they can also act as carriers of various hazardous elements such as heavy metals. Therefore, this study explored possible interactions between polystyrene microplastics (PSMPLs) and two metal pollutants: cadmium chloride (CdCl) and silver nitrate (AgNO). To better understand the extent of biological effects caused by different sizes of PSMPLs, we conducted in vivo experiments with five doses (from 0.01 to 10 mM) that contained polystyrene particles measuring 4, 10, and 20 µm in size on larvae. Additional experiments were performed by exposing larvae to two individual metals, CdCl (0.5 mM) and AgNO (0.5 mM), as well as combined exposure to PSMPLs (0.01 and 10 mM) and these metals, in an attempt to gain new insight into health risks of such co-exposure. Using transmission electron microscopy imaging, we managed to visualize the biodistribution of ingested PSMPLs throughout the fly's body, observing the interactions of such plastics with intestinal lumen, cellular uptake by gut enterocytes, the passage of plastic particles through the intestinal barrier to leak into the hemolymph, and cellular uptake by hemocytes. Observations detected size and shape changes in the ingested PSMPLs. Egg-to-adult viability screening revealed no significant toxicity upon exposure to individual doses of tested materials; however, the combined exposure to plastic and metal particles induced aggravated genotoxic effects, including intestinal damage, genetic damage, and intracellular oxidative stress (ROS generation), with smaller sized plastic particles + metals (cadmium and silver) causing greater damage.
生物有机体如今持续暴露于微塑料和纳米塑料（MNPLs）中，并且除了其潜在毒性外，它们还可作为各种有害元素（如重金属）的载体。因此，本研究探讨了聚苯乙烯微塑料（PSMPLs）与两种金属污染物：氯化镉（CdCl）和硝酸银（AgNO）之间可能的相互作用。为了更好地理解不同尺寸的PSMPLs所引起的生物效应程度，我们对幼虫进行了体内实验，使用了五剂（从0.01至10 mM）含有尺寸为4、10和20 µm的聚苯乙烯颗粒的物质。通过将幼虫暴露于两种单独的金属CdCl（0.5 mM）和AgNO（0.5 mM），以及同时暴露于PSMPLs（0.01和10 mM）与这些金属，进行了额外的实验，试图深入了解这种共同暴露的健康风险。使用透射电子显微镜成像，我们成功地可视化了摄入的PSMPLs在果蝇体内的生物分布，观察到此类塑料与肠腔的相互作用、肠道肠上皮细胞的细胞摄取、塑料颗粒通过肠道屏障泄漏到血淋巴中以及血细胞的细胞摄取。观察发现摄入的PSMPLs的大小和形状发生了变化。卵到成虫的活力筛选显示，暴露于单个剂量的测试材料时没有明显毒性；然而，塑料和金属颗粒的联合暴露诱导了加重的遗传毒性效应，包括肠道损伤、遗传损伤和细胞内氧化应激（活性氧生成），较小尺寸的塑料颗粒 + 金属（镉和银）造成的损害更大。
