I dont know if you seen this already, ConsumerLabs gives a free access to a report they did on multivitamins and some supplement companies failed. I was kind of suprised a few very common brands failed the test. Weird, since their are supposed to be GMP, and one of them even says on the label (at least of some products) that they are third party tested.
https://www.consumerlab.com/trialsignup ... =DROZTRIAL
https://www.consumerlab.com/trialsignup ... =DROZTRIAL