School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen, AB10 7GJ, UK.
School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen, AB10 7GJ, UK.
Environ Pollut. 2022 Jun 15;303:119135. doi: 10.1016/j.envpol.2022.119135. Epub 2022 Mar 10.
Plastics are utilised globally but are of environmental concern due to their persistence. The global presence of microplastics (particles <5 mm in all dimensions) in freshwater environments is increasingly reported, as has the presence of cyanobacterial toxins, including the microcystins. We elucidated the potential role of microplastics as a vector for eight microcystin analogues. Two sizes of polypropylene (PP) and polyethylene terephthalate (PET) microparticles were evaluated. The median particle size distribution (D) was 8-28 μm for small particles, and 81-124 μm for large particles. Additionally, microcystin-LR and -LF were evaluated individually using small PP and PET to elucidate the adsorption behaviour in the absence of competition. Microcystin hydrophobicity, polymer material, and particle size were key factors influencing adsorption to the plastic microparticles. The small size PP microparticles demonstrated a high affinity for the 8 microcystin analogues. The proportion of microcystin adsorbed onto the small particles of PP after 48 h contact was between 83 and 100%, depending on the analogue. Of all analogues investigated, only microcystin-LW and -LF adsorbed onto the larger sized PP and PET microparticles. Individually, greater amounts of MC-LF adsorbed onto the small PET (19%) compared to when it was present in the mixture of microcystins (11%). While MC-LR did not adsorb onto small PET microparticles in the mixture, 5% adsorption was observed when individually in contact with small PET microparticles. The results demonstrated that microplastics can adsorb eight different microcystin analogues and that more hydrophobic analogues are more likely to adsorb than less hydrophobic analogues.
塑料在全球范围内得到广泛应用，但由于其持久性，对环境造成了关注。微塑料（所有尺寸均小于 5 毫米的颗粒）在淡水环境中的全球存在情况越来越多，同时也存在蓝藻毒素，包括微囊藻毒素。我们阐明了微塑料作为八种微囊藻毒素类似物载体的潜在作用。评估了两种尺寸的聚丙烯（PP）和聚对苯二甲酸乙二醇酯（PET）微颗粒。小颗粒的中值粒径分布（D）为 8-28 μm，大颗粒的为 81-124 μm。此外，还单独使用小 PP 和 PET 评估了微囊藻毒素-LR 和 -LF，以阐明在没有竞争的情况下的吸附行为。微囊藻毒素疏水性、聚合物材料和颗粒大小是影响吸附到塑料微颗粒的关键因素。小尺寸的 PP 微颗粒对 8 种微囊藻毒素类似物表现出高亲和力。经过 48 小时接触后，小 PP 颗粒上吸附的微囊藻毒素比例在 83%至 100%之间，具体取决于类似物。在所研究的所有类似物中，只有微囊藻毒素-LW 和 -LF 吸附到较大尺寸的 PP 和 PET 微颗粒上。单独情况下，微囊藻毒素-LF 吸附到小 PET（19%）上的量大于其存在于微囊藻毒素混合物中时（11%）。虽然微囊藻毒素-LR 没有在微囊藻毒素混合物中吸附到小 PET 微颗粒上，但当与小 PET 微颗粒单独接触时，观察到 5%的吸附。结果表明，微塑料可以吸附八种不同的微囊藻毒素类似物，并且疏水性更强的类似物比疏水性较弱的类似物更有可能被吸附。
