We have all heard about high levels of metals that are in protein powders haven't we ?
Many folks will power down 4-6 of these drinks daily not realizing the hidden extras that accompany them. Arsenic, mercury, lead, and many other metals are in that powder you elect to drink as a source of protein. Personally I use protein powder but limit consumption to post workout for a shot of fast absorbing protein, and a casein shake before bed for its slow absorbing properties. All other protein should be obtained via food !! With Chicken, beef, beans, and plenty of other protein sources to choose from, solid protein is the way to go IMO.
Consumer reports did extensive testing quite some time back and it really sparked debates on the integrity of these supplements. Here is a good link that contains a chart on the top 15 protein powders and you will also fine consumer reports link on their study.
Google this topic and you will find numerous articles on this topic similar to this one:
http://www.thehealthyboy.com/2010/07/heavy-metals-found-in-your-protein.html?m=1