The effect of boron concentration in water on the gamma, fast and slow neutrons and alpha particles components at the central, forward and backward surfaces inside tumor phantom of 4.2 cm diameter and 4.4cm height, during brachytherapy by neutrons from 252Cf were investigated. The source was at the centre of a cubic shaped water phantom of 30 cm side. The study was carried for different concentrations of boron from H3BO3, Li2B4O7 and H310BO3. The effect of source to tumor distance on the different components of radiation was also measured. The results indicated that the use of 10B compounds enhances the damage and is recommended for successful boron neutron capture therapy (BNCT).