Fractionation of environmental radioactivity in road dust from a megacity: external and internal health risks

Environ Sci Pollut Res Int. 2024 Jan 4. doi: 10.1007/s11356-023-31657-4. Online ahead of print.ABSTRACTNaturally occurring radioactive materials (NORMs: 232Th, 226Ra, 40K) can reach our respiratory system by breathing of road dust which can cause severe health risks. Targeting the pioneering consideration of health risks from the NORMs in road dust, this work reveals the radioactivity abundances of NORMs in road dust from a megacity (Dhaka) of a developing country (Bangladesh). Bulk chemical compositions of U, Th, and K obtained from neutron activation analysis were converted to the equivalent radioactivities. Radioactivity concentrations of 226Ra, 232Th, and 40K in road dust ranged from 60-106, 110-159, and 488-709 Bq kg-1 with an average of 84.4 ± 13.1, 126 ± 11, and 549 ± 48 Bq kg-1, respectively. Estimated 226Ra, 232Th, and 40K radioactivities were, respectively, 1.7-3.0-, 3.7-5.3-, and 1.2-1.8-folds greater than the affiliated world average values. Mechanistic pathway of NORMs' enrichment and fractionation relative to the major origin (pedosphere) were evaluated concerning the water logging, relative solubility-controlled leaching and translocation, climatic conditions, and aerodynamic fractionations (dry and wet atmospheric depositions). Computation of customary radiological risk indices invokes health risks. Noticing the ingress of NOMR-holding dust into the human respiratory system along with the associated ionizing radiations, the computed radiological indices rep...
Source: Environmental Science and Pollution Research International - Category: Environmental Health Authors: Source Type: research