I need to correct a misconception concerning lead. Lead readily
transfers into human milk at a rate proportional to maternal blood
levels(milk/plasma ration =3D 1). One study evaluated lead transfer into
human milk in a population of women with an average blood lead of 45 =B5g/dL
(considered very high). The average lead level in milk was 2.47 =B5g/dL.
Using these parameters, the average intake in an infant would be 8.1
=B5g/kg/d. The daily permissible level by WHO is 5.0 =B5g/kg/d. Using=
these
parameters, mothers contaminated with lead should not breastfeed their
infants. Permissible levels (CDC) in USA children have dropped from 25 to
less than 10 =B5g/dL in the last decade. Lead poisoning significantly=
alters
IQ, and mental development, particularly in infants.
Tom Hale, Ph.D.
Texas Tech University
Dept. of Pediatrics