Breastfeeding and PFAS

Breastfeeding and PFAS

Research shows breastfeeding is the best source of nutrition for most infants. Breast milk can be a source of per- and polyfluoroalkyl substances (PFAS), but its health benefits include reduced risk of:

• Ear and respiratory infections.
• Asthma.
• Obesity.
• Sudden infant death syndrome (SIDS).

For mothers, breastfeeding can help lower their risk of:

• High blood pressure.
• Type 2 diabetes.
• Ovarian and breast cancer.^[1]

The American Academy of Pediatrics (AAP) and the Dietary Guidelines for Americans, 2020-2025 recommend the similar guidance:

1. Exclusively breastfeed for about the first 6 months.
2. Then, while introducing age-appropriate foods, continue breastfeeding for one to two year or longer as desired by the mother and infant12.

PFAS in breast milk

There are many things to think about when deciding to breastfeed. One of these may be the risk of exposing an infant to environmental chemicals, like PFAS, that can pass through to breast milk.

PFAS are widely spread throughout the environment. Most people in the U.S. and other industrialized countries have measurable amounts of PFAS in their blood. Research studies have shown that PFAS can be found in human breast milk and excreted through lactation.^[3]

How PFAS enter breast milk is not fully understood. The level of exposure for an infant depends on a number of circumstances, including:

• Level of PFAS in the mother
• Amount of PFAS that transfers to the breast milk
• How long the infant is breastfed

Testing breast milk for PFAS

Laboratories can now detect and measure small amounts of PFAS in human breast milk. However, measuring PFAS in breast milk is not a routine test performed by most commercial laboratories:

• The composition of breast milk is complex.
• Factors that influence the concentration of PFAS in breast milk are not completely understood.
• Some studies show that levels of PFAS may vary depending on the time of breast milk collection during a single feed or throughout the course of lactation34.
• How breast milk samples are collected, stored, and shipped must minimize or eliminate the possibility of contamination45.
• Testing requires a standard, validated method for detection, extraction, and analysis.
• Quality control methods for human milk are necessary.

PFAS levels measured in breast milk are most helpful when performed as part of a carefully designed research study.

To date, there have not been large-scale biomonitoring studies for PFAS in breast milk to establish reference values for comparison that are representative of the population of breastfeeding women in the United States. Reference values allow physicians and scientists to determine whether a person or group has an unusually high exposure. Further, there is no established PFAS level for breast milk at which a health risk for an infant (or mother) is expected. Without this information, it is difficult to interpret test results.

Some additional limitations with interpreting test results include the following:

• Even with the ability to confirm the presence of PFAS in breast milk, it may be difficult to estimate how much PFAS an infant is absorbing (bioavailability)
• PFAS levels in breast milk cannot determine if exposure is associated with past or present illness and cannot predict future (short- or long-term) illness or adverse health effects in the infant or the mother
• Infants can also be exposed to PFAS during pregnancy and from other sources in their environment, making it extremely difficult to determine if or how much of an infant's body burden of PFAS is from breast milk

Continuing to breastfeed

For the general population, ingestion of PFAS is considered the major human exposure pathway. For some populations, PFAS in the drinking water supply can be an important contributor to PFAS exposure. For infants, breast milk can be a source of PFAS exposure. Even though PFAS have been detected in breast milk, studies have not shown a causal relationship with a specific health effect in infants or children6. In addition to PFAS, an infant could be exposed to other environmental chemicals through breast milk, making it difficult to associate any potential health affect to one chemical or class of chemicals.

With numerous protective health benefits, breast milk continues to be the ideal nutrition for infants, and in nearly every circumstance, the Centers for Disease Control and Prevention and the American Academy of Pediatrics recommend that nursing mothers continue to breastfeed their babies despite the potential presence of environmental contaminants7.

There are circumstances in which an infant may not be able to breastfeed. In this case, if powdered or concentrated liquid formulas are used, they should be mixed with water from a safe source. In addition, it's important for everyone, including nursing mothers and women of reproductive age, to take steps to reduce or eliminate sources of PFAS exposure (e.g., certain foods and food packaging, contaminated drinking water, and stain-repellant and water-repellant materials).

The science on the health risks of PFAS exposure continues to evolve. However, given the scientific understanding at this time, the benefits of breastfeeding outweigh potential risks of PFAS exposure through breast milk. In addition to regular prenatal care, nursing mothers should continue to receive recommended routine post-natal care and are encouraged to engage in discussions with their healthcare provider when questions or concerns arise. Infants and children should also receive regular well-child checkups, recommended vaccinations, and health screening tests appropriate for age.

Consultation with a specialist in occupational and environmental medicine, or others with expertise and experience treating patients exposed to PFAS, may help guide primary healthcare providers with caring for their patients.

A woman's decision to breastfeed is a personal choice, often made in consultation with her healthcare provider. It is a choice made after the consideration of many different factors specific to the mother and child. ATSDR has developed information on PFAS to guide clinicians and aid in this decision-making process8.