Abstract
Radon concentrations and effective radium contents were measured using CR-39 solid-state nuclear track detectors. In this study, 27 local and imported phosphate fertilizer samples (liquid and solid) were collected from markets in eastern Saudi Arabia. The radon concentrations were found to vary from 3.23 +/- 1.2 to 1547 +/- 162 Bq m(-3). The radon exhalation rates and effective radium contents ranged from 1.77 +/- 0.7 to 848 +/- 89 mBq m(-2)h(-1) and from 3.53 +/- 1.1 to 2246 +/- 236 Bq m(-3), respectively. The highest annual effective dose was from a local fertilizer sample (39 +/- 9.8 mSv y(-1)); this value was higher than the world allowed dose. Therefore, these fertilizers can be a significant source of radiological hazards to human health. Strong correlations were found between the radon concentrations, exhalation rates and annual effective doses from the local and imported phosphate fertilizers. The radon concentrations in all fertilizer samples were compared with the recommended value from ICRP (200 Bq m(-3)).