A Study of the Organic and Nonorganic Food Ingredients with Instrumental Neutron Activation Analysis

Abstract

Organic food is welcomed by the general public because people think organic food is more environment-friendly and can introduce a healthy lifestyle. This popular notion is under scrutiny recently. Compared with conventional food, does the organic food we obtained from local farms and/or supermarket chains are actually chemically healthier? In this research, organic fruit and vegetables with USDA certification from local farmers and popular supermarket chains, along with their conventional counterparts, were collected and studied by a radioanalytical method—instrumental neutron activation analysis (INAA). Samples were irradiated by thermal and epithermal neutrons from the PULSTART nuclear reactor. After that, regular gamma-ray spectroscopy was applied to obtain the qualitative and quantitative information of target isotopes. Our preliminary study indicated that there is not much difference in the trace elements content between organic food and its conventional counterpart. Some heavy metals, which are commonly regarded as the source of harmful components, are detected in both categories. In terms of methodology, INAA is proved to be a sensitive radioanalytical tool to tell the elemental information on atomic or nuclear levels. However, as a nuclear technique, it lacks the capability to probe the properties of compounds on the molecular level, which may be the real difference between organic and nonorganic food.