Monitoring of natural radionuclides in soil of District Gurugram, Haryana (India), by gamma spectrometry and statistical analysis.

Radioactive pollutants in soil continuously expose humans and contribute to the radiation dose to the public. Thirty-eight soil samples were collected from the District Gurugram, Haryana (India), and analyzed using a high-purity germanium detector-based gamma ray spectrometry technique. Potassium-40 (40 K), thorium-232 (232Th), and radium-226 (226Ra) activities were measured in soil samples. Activities of 40 K, 232Th, and 226Ra were found as 342 ± 10 to 760 ± 16 Bq/kg with an average of 568 Bq/kg, 35 ± 1.0 to 83 ± 3.4 Bq/kg with an average of 55 Bq/kg, and 48 ± 1.9 to 90 ± 3.7 Bq/kg with an average of 65 Bq/kg, respectively. The gamma index and alpha index were calculated and found in the range of 0.48 to 0.95 and 0.24 to 0.45, respectively. Descriptive statistical analysis, including the Shapiro-Wilk test for normality assessment, the Spearman rank correlation test to investigate monotonic relationship among these three radionuclides, and the Kruskal-Wallis test to investigate geology (lithological) influence on radionuclide levels, was carried out. Absorbed dose rate and annual effective dose rate for indoor and outdoor were estimated from measured radionuclide levels. Results are compared with the permissible limits of international agencies.