Lead and Breastmilk-for the record

I'm not mad, but this suggestion that I'm poisoning my children through my milk has come up (twice for lead, a few other times for excema, etc.) so I'd like to pass along some info. Yes, it is possible, though HIGHLY unlikely for lead to pass through my milk to my children. When should a mother stop breastfeeding because of lead?
The answer is probably NEVER, unless she has severe lead poisoning.
And again, if I was the source of the lead, as I breastfed each child, more of the lead would be leaving me through the milk, and there would be less lead for each child, thereby meaning with each child their lcad level would be lower(relatively, each body absorbes lead differently) Which is not the case.
Assorted facts from various sources:

lead does not concentrate in breast milk because it does not attach to fat; indeed, levels of lead are generally higher in a mother's blood than in her milk. Several studies have found higher blood lead levels in formula-fed infants than in breast-fed infants.12 This may be a result of contaminated formula cans or formula prepared using tap water with high lead levels. Lead levels in blood and breast milk correlate closely with areas where lead is still used in gasoline, with the highest levels in areas with heavy traffic


Because breast milk is an ever changing substance, it can be difficult to measure and the literature shows a wide range of results. There has also been the problem of contaminated specimens. What has been found, is that the lead levels in breast milk are related to the lead levels in a mother's blood, but breast milk contains only 5% or less of this amount. Having your blood level checked is a simple way of estimating the risk to your baby. (If you are pregnant, ask your doctor to request a lead level with your next tests or ask your GP - this test is covered by Medicare).
Lead moves from where it is stored in a mother's skeleton, during later pregnancy and lactation, when the need for calcium increases. Maintaining your calcium intake will give the body plenty of circulating calcium in the blood which can be used easily by the body to meet the increased need of the foetus. This means there is less likelihood of the body using the skeletal calcium which might induce lead to leave the bones and enter the blood stream.
The 1994 Australian Market Basket Survey found only trace or undetectable levels of lead in breastmilk, cows milk and infant formulas including soy based formula. In the 1992 Australian Market Basket Survey, lead was below the detection limit in all breastmilk tested. Soy based infant formula had lead levels 4 times the detection limit and other infant formula had 3 times the detection limit. In Broken Hill, which is a lead rich environment, the mothers tested had levels that were one tenth of the amount considered to be a problem for breastfeeding.


Sources of lead (but this list is not all-inclusive, other things can have lead in them)

Common Sources of lead:
Lead-Based Paint
Lead Dust
Soil
Food
Water
Other

Unlike the persistent organic pollutants (POPs), metals do not accumulate in fat, and so do not usually achieve higher concentrations in breast milk than in blood. As a result, infants are likely to be exposed to higher levels before birth than during breastfeeding.

All of these contaminants are more likely to affect bottle-fed infants because they are water contaminants and are often found at higher concentrations in infant formula as compared with breast milk.

Breast Milk Overview
In general, the metals found in breast milk are usually at lower levels than are found in maternal blood.4 Thus, breast milk is not the primary pathway of exposure for infants; prenatal trans-placental exposure is a much greater concern. That said, instances of high exposure through breast milk do occur, and are often important indicators of an infant's total exposure. One study found that longer duration of breastfeeding was associated with poorer infant growth in children whose mothers had higher levels of mercury in their bodies. Generally, infants fed formula made with tap water are at the highest risk from metals contaminating the water supply.

This is me-Sajmom-talking here. Essentially what you can take from all this is that it's possible, but only in a case where the mother has had a significant lead exposure herself. Adults process lead quicker than children, and adults wash their hands more (removing the lead before it's ingested) and are less likely to put their hands in their mouths to begin with. So it's very unlikely that I have large amounts of lead in my body. Levels of lead aren't very high in a mother's milk to begin with and only 5% of the mother's level will pass through to the child. So the mother's lead level would have to be very high in order to significantly affect the child. In our case our house has more than enough lead to explain the children's high levels. And the health department agrees.