微塑料在整个环境中无处不在,但与水生和陆地微塑料不同,空气中的微塑料受到的科学关注较少。这项研究是首次明确检查在伊斯兰堡使用主动空气采样器收集的室内和室外空气(PM2.5)样品中的微塑料,巴基斯坦。使用ATR-FTIR分析可疑的合成颗粒,μ-拉曼和SEM-EDX根据它们的形态特征对它们进行分类,聚合物组合物,和元素化妆。在所有室内和室外空气样本中都发现了微塑料,室内空气样品(4.34±1.93项/m3)的污染程度明显高于室外空气样品(0.93±0.32项/m3)(P<0.001)。在所有室内空气样本中,从教室采集的样品(6.12±0.51项目/m3)比从走廊采集的样品(4.94±0.78项目/m3)和实验室采集的样品(1.96±0.44项目/m3)受污染更严重。在室内和室外空气传播的微塑料中,纤维被发现是普遍的形状类型,其次是碎片。透明和黑色的微塑料颗粒在室内和室外空气样品中占主导地位。根据ATR-FTIR分析,聚对苯二甲酸乙二醇酯(PET),聚乙烯(PE),聚丙烯(PP),和聚苯乙烯(PS)是在室内和室外环境中最普遍的聚合物类型。μ-拉曼分析的结果证实了通过ATR-FTIR鉴定的聚合物的存在。通过SEM对颗粒的形态分析表明颗粒表面有风化的迹象,即凹槽,休息,切碎的边缘,坑等。随机选择的颗粒的SEM-EDX揭示了C和O作为核心元素的存在,随着重金属的存在,由于异物附着在他们的表面。环境因素的相关分析,即,PM2.5,相对湿度,温度,风速与MP丰度的关系不显著。这项研究的结果要求对机载MP进行进一步研究,以更好地理解它们的分散,毒性,与其他空气污染物的相互作用,和可归因于的健康风险。
Microplastics are ubiquitously pervasive throughout the environment, but unlike aquatic and terrestrial microplastics, airborne microplastics have received less scientific attention. This study is the first of its kind to explicitly examine microplastics in the indoor and outdoor air (PM2.5) samples collected using active air samplers in Islamabad, Pakistan. The suspected synthetic particles were analyzed using ATR-FTIR, μ-Raman and SEM-EDX to categorize them based on their morphological characteristics, polymeric composition, and elemental makeup. Microplastics were found in all indoor and outdoor air samples, with indoor air samples (4.34 ± 1.93 items/m3) being significantly more contaminated than outdoor air samples (0.93 ± 0.32 items/m3) (P < 0.001). Among all the indoor air samples, samples taken from classroom (6.12 ± 0.51 items/m3) were more contaminated than samples taken from hallway (4.94 ± 0.78 items/m3) and laboratory (1.96 ± 0.44 items/m3). Fibers were found to be the prevalent shape type in indoor and outdoor airborne microplastics followed by fragments. Transparent- and black colored microplastic particles were predominant in both indoor and outdoor air samples. According to ATR-FTIR analysis, polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), and polystyrene (PS) were the most prevalent polymer types in both indoor and outdoor environments. Results from μ-Raman analysis corroborated the presence of the polymers identified by ATR-FTIR. Morphological analysis of particles by SEM indicated signs of weathering on particles\' surface i.e., grooves, breaks, shredded edges, pits etc. SEM-EDX of randomly chosen particles unraveled the presence of C and O as core elements, along with the presence of heavy metals at some spots due to foreign material adhering to their surface. Correlation analysis of environmental factors i.e., PM2.5, relative humidity, temperature, and wind speed with MPs abundance revealed non-significant relationships. The findings of this study call for further research on airborne MPs to better comprehend their dispersion, toxicity, interactions with other air pollutants, and attributable health risks.