Assessment of PM₂.₅ and PM₁₀ Pollution Sources and Exposure in ECDE Centers in High-Traffic and Industrial Areas of Nairobi City County, Kenya
Maurice Kavai *
Kenyatta University, Nairobi, Kenya.
Esther Kitur
Kenyatta University, Nairobi, Kenya.
*Author to whom correspondence should be addressed.
Abstract
Air pollution, particularly particulate matter (PM₂.₅ and PM₁₀), has emerged as a major environmental and public health challenge in rapidly urbanising cities, including Nairobi City County. Early Childhood Development Education (ECDE) centres located near high-traffic roads and industrial zones are especially vulnerable because of continuous exposure to emissions from vehicles, industrial activities, construction dust and other urban pollution sources. Young children are at higher risk because of their developing respiratory systems, higher breathing rates and prolonged exposure within school environments. This study aimed to assess and analyse the primary sources of PM₂.₅ and PM₁₀ pollution and determine their concentrations in selected ECDE centres in high-traffic and industrial areas. A descriptive cross-sectional research design was adopted, involving 120 ECDE children drawn from six ECDE centres. Data were collected using structured questionnaires, observation checklists, portable air-quality monitoring devices and key informant interviews with teachers and caregivers. Secondary data were obtained from the National Environment Management Authority (NEMA), Kenya Meteorological Department, World Health Organization, United Nations Environment Programme and peer-reviewed literature. Data were analysed using descriptive statistics, independent-samples t-tests, Pearson correlation and multiple regression analysis. The findings revealed that ECDE centres located near major highways recorded higher PM₂.₅ concentrations ranging from 38 to 82 µg/m³, while centres located in industrial zones recorded higher PM₁₀ concentrations ranging from 72 to 156 µg/m³. In both cases, the recorded levels exceeded the WHO recommended air-quality guidelines. The results further showed a strong positive correlation (r = 0.71, p < 0.01) between particulate matter exposure and the prevalence of respiratory symptoms among children aged 3–6 years, including coughing, wheezing and frequent colds. The study concludes that vehicular emissions and industrial activities are the primary contributors to elevated PM₂.₅ and PM₁₀ levels in ECDE environments and may pose respiratory health risks to children. It recommends stricter enforcement of air-quality regulations, strategic zoning of schools away from pollution hotspots and enhanced air-quality monitoring in urban educational settings to safeguard child health.
Keywords: PM₂.₅, PM₁₀, ECDE centres, particulate matter, traffic emissions, industrial emissions, air pollution exposure, respiratory symptoms, child health