Homogeneity study is one of the steps in reference material, RM, characterization. Due to its inherent characteristics, Instrumental
Neutron Activation Analysis, INAA, is an analytical technique of choice for homogeneity testing. An interesting possibility
is the use of complementary gamma ray photopeaks to confirm INAA homogeneity test results. In this study, the use of the complementary
gamma ray photopeaks of 110mAg, 82Br, 60Co, 134Cs, 152Eu, 59Fe, 140La, 233Pa (for Th determination), 46Sc and 75Se radionuclides was investigated in the between bottle homogeneity study of a mussel candidate RM under preparation at IPEN–CNEN/SP.
Although some photopeaks led to biased element content results, the use of complementary gamma ray photopeaks proved to be
helpful in supporting homogeneity study conclusions for the new RM under characterization.