Biomonitoring of 137Cs fall-out in Kudankulam coastal waters, Gulf of Mannar, India

Concentration of fall-out 137Cs activity was monitored for a period of 3 years in coastline surface, near-shore surface and bottom waters of Kudankulam coast where a mega nuclear power station is being set up. Activity of 137Cs was estimated by HPGe gamma spectrometry after chemical processing with AMP (ammonium molybdophosphate). The total 137Cs concentration ranged from 1.2 to 1.6 mBq/L in coastline surface waters and between 0.75 and 1.4 mBq/L in near-shore surface and bottom waters. The data set followed a log-normal distribution. An insignificant relationship between 137Cs and salinity, temperature and pH was noted. No yearly variation and no variation between surface and bottom waters were observed (p > 0.05) in the concentration of 137Cs. The 137Cs activity between seasons was found to be significantly different (p < 0.05). (author)