Consumer Reports purchased 15 protein powders and drinks and tested multiple samples of each for arsenic, cadmium, lead, and mercury. Levels in several of the products could, with just three servings a day, result in daily exposure to arsenic, cadmium, or lead exceeding USP limits.
When taking into account the large serving size suggested, the number of micrograms per day for these products was comparatively high.
According to ABC 6 Action News:
"Cadmium raises special concern because it accumulates in and can damage the kidneys, the same organs that can be damaged by excessive protein consumption. And it can take 20 years for the body to eliminate even half the cadmium absorbed today."