A picogram is a one-trillionth of a gram,” Novitzky told
MMAjunkie. “If you put one grain of salt on the table and split it up into 50 million pieces, a picogram is one of those pieces of that gram of salt. These levels have shown up in the single and double digits of picograms – so such a small amount.”
Just find this funny how he say a picogram is one trillionth of a gram, which is correct, but then says to split a gram of salt into 50 million pieces and one piece would be a picogram. Didn't know one out of 50 million is equal to one trillionth. Apparently I have to go back to maths.