(b) Concentrations of lead in the bloodstream are often quoted in units of μg/dL. Averaged over the entire country, the mean concentration of lead in the blood was measured to be 1.6 μg/dL in 2008. Express this concentration in ppb.

Video transcript

hi everyone for this problem. It reads arsenic and all its inorganic compounds are highly toxic substances. A blood concentration of more than five micrograms per deciliter of arsenic is harmful to human health. A study performed on a small number of people working in the alloy industry found an average concentration of 8.5 micrograms per deciliter, expressed this concentration in parts per million units. Okay, so our goal here is to express this 8.5 micrograms per deciliter and parts per million units. So let's go ahead and define what are parts per million unit is one part per million is equal to one mg per leader. Okay, so our goal here is to go from 8.5 micrograms per deciliter, two mg per liter. So let's go ahead and write out what we're starting with. So we're starting with 8. micrograms per desolate er. Okay, so let's go ahead and first convert our micro grams to milligrams. Okay, and we can use the conversion of micrograms two g. So one microgram Is equal to 10 to the -6 g. Okay, but we need to take it a step further because one part per million is milligrams. Okay, so now we need to go from grams to milligrams in one mg. There is 10 to the negative three g. Okay, so let's just make sure our units are canceling properly. So these micrograms cancel these grams cancel and we're left with milligram which is perfect. So now we need to go from desa leader to Leader. Ok and the conversion that we can use for that is in one desolate er There is 10 to the -1 leader. Okay. And so now this desolate er will cancel with this one and we're left with Leaders and so now we're in our desired units milligrams per liter. So let's go ahead and do this final calculation. And when we do that we get zero point 085 mg/s, which is also parts per million. Okay, so this is going to be our final answer expressed in parts per million units. That's the end of this problem. I hope this was helpful.