Estimation of 239Pu in fecal sample using simulant matrix

Estimation of 239Pu in faeces following accidental exposure to insoluble aerosols like plutonium oxide is the best means of obtaining an indirect assessment of the intake. As part of providing radiological surveillance to plutonium handling workers, a technique has been developed and standardised for analysis of 239Pu in fecal sample. For developing the technique cow dung and simulant fecal matrices spiked with 239Pu have been used. The sample was ashed and the silica was eliminated by treating with HF-HNO3 mixture. 239Pu was separated on anion exchange and electrodeposited. The interfering elements such as Fe, Si were removed by washing the column. The percent recovery of 239Pu by this method was 86.14±3% with a minimum detectable activity of 12.6 mBq. Experiments were repeated with a matrix which simulates fecal matter. The percent recoveries and the minimum detectable activities in both cow dung and simulant faeces were comparable. This method can detect activity less than one derived investigation level even on tenth day following exposure of 239Pu due to inhalation. (author). 10 refs., 2 tabs