The integral approach for preparing reviews is in my opinion. Start with a existing leading article or review. Study it thoroughly and read the relevant references from this paper. Repeat this procedure till you vind no more new items. Search the net for any new information on your topic. Then the important work starts: organizing and writing down the collected information. Good Lucky!
You can see the new sources and learn about the ways of growth and reproduction of aflatoxins, their types and dangers. This is a review of your topic.