Plants in general can contain more lead from soil whereas animals will filter it out before you consume their flesh, but the amounts they found were still well below what is recommended for other plant products such as fruit juice. After looking into it when I saw that study it kinda sucks how much lead is still in a lot of things. I’d be curious to see a bigger study comparing the lead found in people that use the plant-based powder or are vegetarian versus meat-eaters.