2024 Yes Risk Assessment and Implications of Schoolchildren Exposure to Classroom Heavy Metals Particles in Jeddah, Saudi Arabia https://www.mdpi.com/1660-4601/16/24/5017 Alghamdi, Mansour A Asia Exposure Modeling Elementary (K-5) Dust Heavy metals Filtration Classrooms air conditioner filter particles Heavy metals Contamination level Indoor air quality Health Risk Air conditioner filter dust from Jeddah schools showed high heavy metal contamination, especially in urban areas. Cd, Pb, and Co posed the highest risks. Ingestion was the primary exposure route, supporting stronger IAQ controls and filtration. 2019