Governments are being urged to do more to regulate the advertising of infant formula sent offshore.
Australian National University has published a paper in the International Breastfeeding Journal on the environmental damage of milk formula.
Author Dr Julie Smith told Kate Hawkesby studies show a tin of formula generates up to 11 kilograms of carbon-equivalent greenhouse gases.
She says it starts to add up.
"We're looking probably around 20 million tonnes of greenhouse gas emissions from baby formula each year."
She says governments could do a lot more to curb the marketing of the products.
"We've got restraints in Australia and New Zealand, for example, which limit the aggressive marketing of baby formula to mothers, and we don't apply that to our export industry."