Interior settled dust is one of the greatest threats of potentially toxic metal(oid)s (PTMs) exposure to the children, especially in the school environment. Therefore, it is more worthy of having in-depth knowledge of compositional characteristics of school dust. Forty schools were selected of Lahore city for dust sampling. The school dust was analyzed to determine the PTMs (As, Cd, Cr, Cu, Ge, Mo, Ni, Pb, Sb, Sn, Sr, V, and Zn) concentrations using ICP-MS. The morphological characteristics, PTMs speciation, and mineralogy of school dust were examined using SEM with EDS, XPS, and XRD, respectively. Moreover, the geo-accumulation index (I_geo), potential ecological risk index (PERI), and multivariate statistical analysis were employed to assess the pollution levels, ecological risk, and source identification of PTMs, respectively. The I_geo indicated a heavily-extreme pollution level of Cd (I_geo=4.92), moderate-heavy pollution of Zn (I_geo=3.22), and Pb (I_geo=2.78), and slight-moderate pollution of Cr (I_geo=1.62), and Cu (I_geo=1.53). The ecological risk has been found extremely high for Cd and moderately high for Pb and As, while potential ecological risk found extremely high posed by cumulatively all selected PTMs. Multivariate statistical analysis showed that sources of PTMs comprise of natural processes as well as several anthropogenic processes like vehicular emissions, agricultural and industrial activities. The SEM, XRD, and XPS analyses demonstrated the presence of airborne particles and PTMs containing minerals with several toxic chemical species in school dust. This study can help to develop strategies to reduce school indoor pollution and hence to establish an eco-friendly learning environment for children.

内部沉降的灰尘是可能有毒的金属（PTM）暴露于儿童的最大威胁之一，尤其是在学校环境中。因此，更值得深入了解学校粉尘的成分特征。拉合尔市选择了40所学校进行灰尘采样。使用ICP-MS分析学校的灰尘以确定PTM（砷，镉，铬，铜，锗，钼，镍，铅，铅，锑，锡，锶，钒和锌）的浓度。使用EDS，XPS和XRD的SEM分别检查了学校灰尘的形态特征，PTM形态和矿物学。此外，地理累积指数（I _geo），潜在生态风险指数（PERI）和多元统计分析分别评估了PTM的污染水平，生态风险和来源识别。I _geo表示Cd的极度污染水平（I _geo = 4.92），Zn的中度重度污染（I _geo = 3.22）和Pb（I _geo = 2.78）和Cr（I _geo = 1.62）和Cu（I _geo= 1.53）。已发现镉的生态风险极高，而铅和砷的生态风险极高，而累积的所有选定PTM所带来的潜在生态风险极高。多元统计分析表明，PTM的来源包括自然过程以及一些人为过程，例如车辆排放，农业和工业活动。SEM，XRD和XPS分析表明，学校尘埃中存在含有矿物和几种有毒化学物质的矿物的空气传播颗粒和PTM。这项研究可以帮助制定减少学校室内污染的策略，从而为儿童建立一个生态友好的学习环境。