The National Childbirth Trust (NCT) called for clearer labelling on bottles to show which ones are more likely to leach the chemical.
Chief executive Belinda Phipps said: ‘Although the level of risk is not certain, parents are largely unaware of this risk and do not know which bottles to avoid.
‘As a first step, it is important that bottles and other items that might reach a baby’s mouth, are labelled in a standard and easy to understand way.’
Bisphenol A is a chemical that causes damage to humans and animals during critical stages in their development.
It mimics the effects of oestrogen in the body and affects reproductive, neurological and immune systems.
The chemical is a monomer used to make polycarbonate and epoxy resins found in some feeding bottles.
Bottles containing Bisphenol A are not likely to leach the chemical at room temperature – but if bottles are warmed, for instance during sterilisation or washing, the likelihood of leaching increases.
Polycarbonate bottles that often have the number seven in the recycling triangle on the bottle, or the letters "PC" near the recycling triangle that leach Bisphenol A. Some plastic bottles do not leak it and glass bottles do not.