Okoro Hussein K, Orosun Muyiwa M, Agboola Afisat F, Emenike Ebuka Chizitere, Nanduri Sireesha, Kedia Navin, Kariem Muthena, Priya Ati, Rab Safia Obaidur
Environmental-Analytical & Material Science Research Group, Department of Industrial Chemistry, Faculty of Physical Sciences, University of Ilorin, P. M. B. 1515, Ilorin, Nigeria.
Department of Chemistry and Industrial Chemistry, Faculty of Pure and Applied Sciences, Kwara State University, P.M. B 1530, 241104, Malete, Nigeria.
Heliyon. 2025 Feb 19;11(4):e42769. doi: 10.1016/j.heliyon.2025.e42769. eCollection 2025 Feb 28.
Over the past three decades, heavy metals (HMs) in indoor dust have been a significant focus due to their environmental and health risks. This study assessed HM contamination (Co, Pb, Cd, Cr, Ni, and As) in classroom and lecture theatre dust in Ilorin, Nigeria, across dry and rainy seasons. Dust samples from primary, secondary, and university settings were analyzed using atomic absorption spectrometry and ICP-OES. HM concentrations followed the order As > Pb > Co > Cr > Ni > Cd, all below background values. Indices like geoaccumulation (Igeo), contamination factor (CF), and pollution load index (PLI) indicated minimal contamination. The proportion of human health risks attributed to dermal contact, represented by HQderm and CRderm, accounted for 67.76 % and 30.30 % of the total hazard index (HI) and cancer risk (CR) during the dry season, and 86.76 % and 72.65 % during the rainy season, respectively. Health risks via ingestion, inhalation, and dermal exposure showed children were more vulnerable than adults, with dermal pathways contributing significantly to overall risk. Principal component and geo-spatial analyses highlighted natural and anthropogenic HM sources. The findings provide critical data for policymakers to develop effective strategies for minimizing HM exposure in indoor environments.
在过去三十年里，室内灰尘中的重金属因其环境和健康风险一直备受关注。本研究评估了尼日利亚伊洛林地区教室和讲堂灰尘中重金属（钴、铅、镉、铬、镍和砷）在旱季和雨季的污染情况。使用原子吸收光谱法和电感耦合等离子体发射光谱法对小学、中学和大学环境中的灰尘样本进行了分析。重金属浓度顺序为砷＞铅＞钴＞铬＞镍＞镉，均低于背景值。地累积指数（Igeo）、污染因子（CF）和污染负荷指数（PLI）等指标表明污染程度极低。由皮肤接触导致的人体健康风险比例，以皮肤接触危害商（HQderm）和皮肤接触致癌风险（CRderm）表示，在旱季分别占总危害指数（HI）和癌症风险（CR）的67.76%和30.30%，在雨季分别占86.76%和72.65%。通过摄入、吸入和皮肤接触途径产生的健康风险表明，儿童比成人更易受到影响，皮肤接触途径对总体风险的贡献显著。主成分分析和地理空间分析突出了重金属的自然和人为来源。研究结果为政策制定者制定有效策略以减少室内环境中的重金属暴露提供了关键数据。
