Is it safe to store breast milk in plastic bags that may contain bisphenol analogues?

What's actually in it

Plastic storage bags are often made from materials that contain bisphenol analogues (chemicals like BPA, BPS, and BPF) and microplastics. These materials are not inert. They can leak these chemicals directly into the milk you store for your baby.

When you use plastic bags, you risk exposing your baby to these substances. Bisphenol analogues are known to be endocrine disruptors, and microplastics can carry additional chemical mixtures that your baby does not need in their diet.

What the research says

Peer-reviewed research shows that these materials can have serious consequences for a baby's health. A 2026 study in FASEB J found that polystyrene microplastics disrupt the natural transfer of the breast milk microbiome. This process is critical for your baby's early gut health and immune system development.

Furthermore, a 2026 study in Environ Pollut confirmed that repeated exposure to polyethylene microplastic mixtures containing bisphenols and PFAS (forever chemicals) triggers inflammatory responses in human cells. These findings highlight why plastic is not a safe choice for storing something as sensitive and essential as breast milk.