Natural News published a 2014 article exposing unsafe levels of contaminants and lead in mangosteen product. This analysis included mangosteen products that came with a purported safe Certificate of Analysis, but upon 3rd party testing were found false. Always check for 3rd party testing verification on your health products.
Safety: It is important to note from the studies that mangosteen tested at high levels brought no adverse reactions in cell biology. National Institutes of Health safety studies on mangosteen are numerous. Safety studies from the NIH Peer Medical include fantastic descriptions of mangosteen benefits as well.