Radiological assessments of quarry dust from quarries in Kelantan, Malaysia

Quarry products have been used for various purposes in construction including road and building materials. Although this industry is not considered as major industry in Kelantan the amount and elemental contents of dust that came from the industry warrant a valid concern for the quarry workers and public users of the products. These elements would pose radiological, pollution as well as health risks to workers, public and the environment. The present study focused on quarry dust samples collected from eight locations throughout Kelantan. Natural radioactivity levels from ²³⁸U, ²³²Th and ⁴⁰K were determined using Gamma-ray Spectrometry technique. Depending on location and types of quarries the activity concentration of ²³⁸U ranges from 4.34-144.5 Bq kg⁻¹ and for ²³²Th from 2.35-180.4 Bq kg⁻¹ while for ⁴⁰K ranges from 27.4-595 Bq kg⁻¹ in, respectively. Based on radiological assessment, these activity concentrations yield the radium equivalent (Ra_eq) from 9.6-374 Bq kg⁻¹ with the corresponding External Hazard Indices (H_ex) ranging from 0.04-1.23. The suggested limit for both are 370 Bq kg⁻¹ and 1, respectively. These results could be used to estimate the related risks as well as to establish a baseline data of naturally occurring radionuclides in quarry industries.