Seasonal Study of Lead Content in the Atmospheric Air of the Chorokhi River

The aim of this study was to assess seasonal variations in lead (Pb) concentrations in the atmospheric air of the Chorokhi River basin and determine its potential environmental impact. The Chorokhi River basin is an ecologically important transboundary system with intensive transport, industrial, and agricultural activities, increasing the risk of heavy metal pollution. The study utilized an active biomonitoring based on sphagnum moss, which relies on the moss's ability to accumulate heavy metals from atmospheric air. Bags containing sphagnum moss were placed at six study sites. Lead concentrations were determined using atomic absorption spectrometry (AAS). The results showed that the maximum lead concentration was recorded in winter—0.041 mg/kg—and the minimum—0.020 mg/kg—in autumn. The pollution index showed the greatest significance during the winter period. The study's results confirmed that lead levels in atmospheric air vary seasonally and are significantly influenced by both anthropogenic and climatic factors. Sphagnum biomonitoring is an effective tool for assessing atmospheric air quality.