Comment by mrob

It's bad reporting. The actual numbers from the abstract are "22.1 ng/kg·day" for the worst case ingested dose, and "1000 μg/mL" for the tested toxic concentration. If you assume the solvent is water (solvent isn't specified in the abstract but water is the obvious choice) and convert the units to make it easier to compare, that toxic dose is "1,000,000,000ng/kg". There's no plausible way a toddler is going to accumulate that much within "days".