“Broad conclusions about potential contamination of breastmilk are hard to make. Not only does each case involve a wide array of factors from the diet of the mother to the air she breathes, many of the suspected toxins are new enough to preclude any long-term studies. Claims of contamination must be looked at in light of their source: environmentalists often exaggerate the degree of contamination to boost their case for greater safe-guards, and formula companies freely spread fears of toxins in the hopes that mothers will choose formula as a way of erring on the side of safety. On the other hand, some breastfeeding promoters would have you believe that breastmilk is impervious to contamination.”—Naomi Baumslag, MD, MPH & Dia Michels in the book, “Milk, Money, and Madness: The Culture and Politics of Breastfeeding” 1995. p96.
After rereading the above paragraph; I am bemused, frustrated, and angry. I read the book some 26 years ago and the only thing about that paragraph that has changed is that we are living with more toxic chemicals. Environmentalists still use breastmilk contamination as a means to galvanize the public to create a better environment. Parents read the media reports, become frightened, and believe that infant formula is the answer to contamination in our environment.
MEDIA RESPONSE
This year the media (The Guardian and recently The Seattle Times) have focused on the research paper from Environmental Science & Technology called, “Per-and Polyfluoroalkyl Substances (PFAS) in Breast Milk: Concerning Trends for Current-Use PFAS,” by Guomao Zheng et al. The Seattle Times article was a more informative exposé on the research paper than The Guardian. While The Seattle Times article was informative, it was uncritical of the research paper itself. The article also featured one of mothers, who donated her milk for the research. While personalizing this issue may sway people to support the need to restrict PFAS chemicals in our environment, the uncritical stance of the research paper presumes the accuracy of the research.
The Guardian article that was published a few months ago was inaccurate and alarmist. One of the Guardian’s partners is the Joseph Rowntree Foundation as well as the Bill & Melinda Gates Foundation. Interestingly, the Joseph Rowntree company (maker of the Kit Kat candy bar, Smarties) was bought out by Nestlé in 1988 for $4.5 billion. Nestlé appears to partner (the Living Wage Project in UK) with The Joseph Rowntree Foundation. Nestlé responded to recent queries regarding the history of the Rowntree company and its relationship to the slave trade. When a newspaper partners with foundations that are allied with corporations that have an economic agenda, one might consider that articles in that newspaper might be slanted or biased.
https://www.nestle.co.uk/en-gb/media/pressreleases/nestl%C3%A9-becomes-living-wage-principal-partner
https://www.theguardian.com/environment/2021/may/13/pfas-forever-chemicals-breast-milk-us-study
https://www.theguardian.com/info/2018/oct/02/philanthropic-partnerships-at-the-guardian
“Per- and Polyfluoroalkyl Substances (PFAS) in Breast Milk: Concerning Trends for Current-Use PFAS” by Guomao Zheng et al.
https://pubs.acs.org/doi/10.1021/acs.est.0c06978
After reading and rereading this paper which was the basis for US media headlines this year, I find myself questioning the accuracy of their measurements of PFAS concentrations in breast milk. As a lactation consultant for many years, and having read many research papers over the years; I am somewhat taken aback that research is still being done on breast milk in which a paper does not define feeding methods. Were these mothers breastfeeding exclusively, and how was it defined? Were they partially breastfeeding and using other milks, water, and/or food? Were they pumping their milk exclusively or occasionally or not at all? One might wonder why this would matter, since they are only looking at PFAS chemicals in breast milk. A mother who is exclusively pumping her milk and bottlefeeding the milk or a mom who is partially breastfeeding (using animal or plant milks, water, or foods) would potentially expose her infant thru water, packaging of food products, and plastic bottles to more PFAS chemicals than a exclusively breastfeeding mom (no water, infant formula, or other food and drinks).
One of the facts of breast milk is that it is a substance in which its many components change from hour to hour, day to day, month by month with the fat content being the most variable component. Taking one sample at one moment in time will not give us a full picture of the toxins in breast milk. A woman that is partially breastfeeding or in the process of weaning (protein and sodium increased with a decrease in lactose) will have milk in which the components are more or less concentrated than a woman who is exclusively breastfeeding. This would mean that at different times in the day the woman donating her breast milk may have more toxins in her milk than at other times. Taking human milk samples over a day or over weeks, would give a more accurate view of toxins in a milk sample.
Focusing on PFAS chemicals in breast milk, obscures the reality that babies under a year in the US are not solely being fed at the breast. Most breastfeeding moms by 3 months postpartum are no longer exclusively breastfeeding. Breastfed babies under 6 months may be receiving lots of formula feeds as well as bottles of water. Thus avoiding the issue of other foods and water being ingested by infants is a very narrowed approach to the problem of infant exposure to PFAS chemicals.
It is particularly a problem, when one reads various research papers in which dairy products (some studies includes infant formula), and water are considered high risk foods and drinks for PFAS chemical contamination. Infant formula is often reconstituted with water from municipal water systems.
“Recent studies in the Journal of Dairy Science and Food Science, have examined the bioaccumulation and transfer of PFAS from contaminated feed and drinking water to cow’s milk and results suggest that certain PFAS compounds have a relatively high potential to transfer to milk and beef from the diet of dairy cows.” https://www.bbjgroup.com/blog/crying-over-spilled-milk-the-latest-victims-of-pfas-contamination-in-new-mexico
.“…the number of Americans exposed to PFAS from contaminated tap water has been dramatically underestimated by previous studies…” https://www.bbjgroup.com/blog/crying-over-spilled-milk-the-latest-victims-of-pfas-contamination-in-new-mexico
In a research paper called, “Infant Dietary Exposures to Environmental Chemicals and Infant/Child Health,” published in September of 2018 in Environmental Health Perspective, compared the number of research papers on toxins in breast milk versus toxins in infant formula. They found plenty of studies on breast milk but very few on infant formula. The authors did a literature search using PubMed and the Web of Science (WoS) on human milk and infant formula. They initially found 1,151 studies and 259 citations on human milk, and 139 studies and 644 citations on infant formula. They narrowed down these numbers in both categories according to specific criteria (PECO-Population, Exposure, Comparison, Outcome). None of the infant formula studies passed the PECO criteria and only 74 studies and 11 citations of human milk passed their criteria. I highly recommend this particular study for an understanding of the importance of having data on prenatal exposures of infants, the need for a comparison group-such as infant formula, and documentation of health outcomes of infants.
“A critical gap is a lack of research on environmental chemicals in formula and infant/child health outcomes.”
https://ehp.niehs.nih.gov/doi/10.1289/EHP1954
When we examine the research paper cited by The Guardian and The Seattle Times, there is no comparison of infants being breastfeed versus infant formula fed. Nor do we have any prenatal blood data; even more telling this paper has no data on the mothers’ blood levels of PFAS chemicals. Without paired blood samples from the mothers, they instead used the CDC’s breast milk and serum data published in 2015-2016 of the NHANES (National Health & Nutrition Examination Survey) to calculate the lactational transfer efficiencies. I consider this to be very problematic, a fatal flaw. They also used the US EPA average age-based daily breast milk consumption rates. The US EPA defines exclusive breastfeeding as the “sole source of milk from human milk with no other milk substitutes.” This definition would mean that a mother who gave water and/or food would be considered to be exclusively breastfeeding. Yet we know that water consumption can be a high risk for PFAS chemical exposure.
There are other issues regarding this research. Sixty-eight percent of the mothers were over 33 years old and having their first baby. Older moms would potentially be exposed to more PFAS chemicals than younger mothers. It is believed that first time mothers deliver more toxins to their first born than to their subsequent children. Fifty-two percent of the babies were over 6 months of age. This means that the milk collected for these older babies would be very different from babies under 6 months. I would have liked to have seen samples of milk from mothers with newborns, and at 3 months postpartum. Again, one sample of donated milk does not tell us enough about a breastfed baby’s exposure to toxins. And no comparison made with mothers who do not breastfeed and use infant formula, means our understanding is limited.
The mothers who participated in this research were mostly Caucasian. Sixty-two percent of the mothers had advanced degrees with 46 percent having middle incomes ($70,000-100,000). It would seem that these women would probably have far less exposure to PFAS chemicals than women of lower income. While all populations are important to study PFAS chemicals exposure, I would like to see more studies done on women/babies from riskier environments (those living in more industrial areas where these chemicals are manufactured) in order to get a total picture of the reality of this problem.
One of the more interesting issues brought up in a research paper I ran across states, “Levels of PFASs in breast milk have been reported to be lower than PFAS levels in maternal plasma and serum in matched samples collected from the same donors (Hinderliter et al. 2005; Karrman et al. 2007; Liu et al. 2010).” “Per- and Polyfluoroalkyl substances in human breast milk and current analytical methods,” Macheka-Tendenguwo et al. Environmental Science and Pollution Research, 2018.
This has also been documented in rats. Are breastfed infants being protected from toxins in their mother’s milk? This needs to be more fully explored. This means that studies need to have not just donor milk samples, but also paired blood samples from the mothers in the study.
https://link.springer.com/article/10.1007%2Fs11356-018-3483-z
CONCLUSION
We do have to clean up the environment for the safety of people on earth now and into the future; that is if we want a future. The risk of chemical toxins to infants should be based on accurate statistics of what babies are being fed in their first year of life, babies’ exposure levels prenatally, defining feeding methods as well as including infant formula feeding, the need for multiple milk samples paired to mother’s blood samples, and long term studies on how chemical toxins impact the short and long term health of babies. Focusing only on the chemical toxins in human milk, does a grave disservice to our society, and its ability to safeguard the next generation.
