Microplastics are tiny particles of plastic that have been found across the entire planet—from the deepest oceans to the summit of Mount Everest—places once thought untouched. Everyday items such as baby bottles, breast pump parts, and breast milk storage bags can release these particles, especially when heated. For parents feeding a baby for the first time, this information can feel overwhelming, but understanding how microplastics enter our environment and bodies helps guide safer choices.

Understanding Plastic in Everyday Life

Breast pumps and storage systems often rely on plastic packaging and components because they are practical and convenient. At the same time, growing public awareness of plastic waste and its effects on marine wildlife and the environment has led some families to make intentional choices that reduce use of plastics while still supporting their infant feeding goals. Even small adjustments—like considering alternatives to synthetic fabrics and personal hygiene products—can make a meaningful difference. For healthy mothers, these choices can help minimize exposure for themselves and their babies.

How Microplastics Can Enter Breast Milk

Recent studies suggest that actions such as heating, shaking, or repeatedly reusing plastic bottles and milk storage bags can increase plastic particles in expressed breast milk. This is an important time for new parents to learn which materials are safer for everyday use if planning to incorporate pumping and bottle feeding into the baby's feeding routine. Alternatives such as glass, stainless steel, or silicone may be heavier or less convenient but can help reduce harmful chemicals and overall particle exposure. While the exact impact on infant health is still unknown, reducing unnecessary exposure is a practical precaution.

Prioritizing Direct Breastfeeding

Direct breastfeeding is the best way to reduce your baby's contact with microplastics. Breastfeeding directly lowers reliance on bottles and storage systems, decreasing potential exposure to chemical contaminants and microplastics. Combining direct breastfeeding with mindful handling of bottles and storage containers, when needed, is a practical way to reduce exposure.

Microplastics and Your Baby's Health

Recent research has detected evidence of microplastics in both formula and human breast milk samples, with small studies finding around 39% of samples contain plastic particles. Microplastics have even been identified in amniotic fluid and human placenta, highlighting exposure to pregnant women. While the toxic effects of microplastics are still being explored, these findings do not outweigh the advantages of breastfeeding. Breast milk offers complete nutrition, supports the immune system, improves child health, and is recommended by major health organizations as the best way to feed infants and young children.

Reducing Exposure Further

Parents can take steps to further reduce exposure to microplastics:

  • Choose fewer single-use plastics

  • Replace cracked, cloudy, or worn plastic items

  • Use glass or stainless steel containers when possible

  • Avoid heating food in plastic containers

  • Be mindful of personal care products

Choosing Plastics Wisely

While it’s impossible to eliminate all plastics, thoughtful choices can reduce exposure to microplastics and harmful chemicals.

What Is Polypropylene?

Polypropylene (PP) is a common plastic used in baby bottles and breast milk storage containers. In its intact form, it is considered non-toxic and does not contain Bisphenol A (BPA) or phthalates. However, heating or repeated use can release particles and other chemical contaminants, highlighting the urgent need for ongoing health research priority and further research into exposure and effects on the human body, human blood, and early life stages.

Preliminary evidence from laboratory and small human studies suggests potential health impacts of microplastics may include:

  • Damage to the digestive tract, immune system, and reproductive systems

  • Metabolic disorders

  • Reproductive and developmental toxicity

Other Plastics in Bottles and Pump Parts

Manufacturers have also developed newer, harder plastics to improve durability and reduce chemical leaching. These include:

  • Polyphenylsulfone (PPSU): Heat-resistant, BPA-free, durable, but repeated use can still release tiny particles.

  • Tritan™ copolyester: BPA-free, clear, lightweight, durable, can shed plastic particles under heat or friction.

  • Polyamide (PA): Clear, strong, chemically stable; less common but promising for durability and safety.

While newer plastics may be marketed as safer, any plastic can release tiny particles over time. By giving greater attention to heating, shaking, and reuse of plastic bottles and milk storage bags, parents can minimize microplastic exposure while maintaining convenience.

Everyday Steps to Reduce Exposure

  • Prioritize direct breastfeeding when possible.

  • Prepare and cool milk in glass or stainless steel before transferring to plastic

  • Avoid excessive shaking of bottles or milk storage bags

  • Thaw frozen milk in the refrigerator and transfer to non-plastic containers for warming

  • Hand-wash plastic items, instead of using the dishwasher, to prevent breakdown of plastics

  • Rinse plastic bottles and pump parts with cool water multiple times after dishwashing or sterilizing

Even small adjustments contribute to safer feeding. Finding the right balance between convenience and reduced exposure is key—every action counts toward protecting your baby and supporting human health. While the ubiquitous presence of microplastics makes complete avoidance impossible, simple, mindful practices can help reduce exposure and support your baby’s well-being.

Disclaimer: Our classes and accompanying materials are intended for general education purposes and should not replace medical advice. For personalized recommendations, please consult your healthcare provider and/or lactation consultant.