Supporting Breastfeeding

La Leche League Canada

Toxic Chemicals in Breastmilk

on June 27, 2016

There is no reason to discourage breastfeeding.

The internet is buzzing with articles about toxic chemicals in breastmilk following the release of research [1] done by the Harvard T H Chan School of Public Health which looked at the levels of perfluorinated alkylate substances (PFAS) in breastmilk.
Perfluorinated alkylated substances (PFAS) make up a large group of chemicals which have been used in industrial and consumer products since the 1950s. The substances are mainly used in firefighting foams, protective coatings in food wrappers and containers, stain resistant textiles, floor wax, polish and in the electronic industries. These substances have a high likelihood of ending up in waste dumps, sewage water and the general environment.

The chemicals of the PFAS group are virtually indestructible and were until recently thought to be completely biologically inert and not available for uptake in living organisms. It now appears that they bond with proteins and fats in food sources. Since the late 1990s, increasing numbers scientific studies have brought PFAS chemicals in the focus of international environmental concern. PFAS are shown to be globally distributed and some of them are bioaccumulative which has implications for human exposure.


download (75)

The Harvard research, which was done in the Faroe Islands in conjunction with the Norwegian Government, showed that PFASs are transferred through breastmilk and that blood samples levels increased the longer that babies were breastfed. After the babies were weaned their accumulated PFAS levels decreased. Babies who were exclusively breastfeed had higher levels than partially breastfeed babies. This information is important not as a reason to discourage breastfeeding but because it is a look at PFAS exposure and accumulation levels in both women and children in that community. The tested babies only showed levels of PFASs in their blood samples because their mothers had built up an accumulation of PFASs over their lifetimes which they could pass on.

Presumably every other adult in that community has similar levels of accumulated PFASs.
Choosing to formula feed doesn’t necessarily protect an infant from exposure to these chemicals for two reasons. Firstly the baby has already been exposed in utero. Studies have shown that PFASs cross the placental barrier and high maternal levels can be linked to miscarriages. Secondly, community water supplies can carry high levels of PFASs. Drinking water prepared by treatment which does not include GAC filtration or reverse osmosis will generally contain higher PFAS levels. The potential for exposure to PFASs in formula fed babies through water supply applies both to the water used in the manufacturing of the formula and the water used to prepare it at home.
Philippe Grandjean, adjunct professor of environmental health at Harvard Chan School and spokesperson for the research team said “There is no reason to discourage breastfeeding, but we are concerned that these pollutants are transferred to the next generation at a very vulnerable age. Unfortunately, the current U.S. legislation does not require any testing of chemical substances like PFASs for their transfer to babies and any related adverse effects.”

More information about PFASs can be found at the following links:

Community Drinking Water [2]

Immunization response and PFAS exposure [3]

European Commission Community Research and Development information Service (CORDIS) Final Report summary – PERROOD (Perfluorinated organics in our diet) [4]


Do you have questions or concerns about breastfeeding or are you searching for a supportive community of other breastfeeding mothers? Check out a LLLC group near you.




If you need more information or have a breastfeeding problem or concern, you are strongly encouraged to talk directly to an accredited La Leche League Leader. In Canada, Leaders can be located by clicking or Internationally

If you have found this article helpful, La Leche League Canada would appreciate your support in the form of a donation at so we can continue to help others breastfeed. Thank you!





Your Comments are Welcome

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: