Polypropylene baby bottles shed thousands of microplastic particles into infant formula, a new study in Nature Food has found, exposing infants worldwide to plastic particles at levels thousands of times higher than what adults face through their food and water.
Tiny plastic particles are widespread in our environment. Invisible to the eye, they are known as microplastics, and can be found in the ocean, in our food, in our water – and even in our air. The new study is the first to systematically estimate to what extent bottle-fed babies ingest these particles, and the results are troubling.
Researchers measured the number of microplastic particles in baby plastic bottles after following World Health Organization guidelines for the safe preparation of infant formula. They then analyzed baby bottle sales worldwide and estimated the exposure of babies globally, creating a map of exposure levels. Based on their estimates, which take into account breastfeeding habits, baby bottle sales, and infant daily milk intake, US babies are among the babies most-exposed to microplastics worldwide.
Most baby bottles are made of polypropylene plastic. Many bottles also have polypropylene accessories (bottle caps, straws, shaker balls). But this is the first study to quantify the shedding of polypropylene microplastic particles into infant formula, under recommended use conditions.
Unfortunately we don’t yet know whether this is cause for serious concern. The research quantifies the microplastics migrating from bottles into formula, and estimates how much babies are exposed to depending on their age and where they live. Scientists don’t know how harmful this plastic exposure is, or even whether it’s harmful. That’s something that would need to be determined in subsequent studies. What this gives us is a better understanding of global exposure levels.
The new study comes at a time when having a baby is especially complex and stressful. With limited information on the impact of COVID-19 on moms and babies, new moms are entering uncharted territory and may be paying special attention to hygiene and sterilization. There’s also some evidence that COVID is making plastic pollution worse.
This study determined that babies are exposed to average levels of microplastic particles in excess of 1 million per day, with generally higher rates in developed regions. This is about 2,600 times the total adult consumption of microplastic particles from water, food and air (up to 600 particles per day).
The health impacts of this exposure are unknown, so until we learn more, practice commonsense prevention strategies.
- Avoid heating your baby’s formula, breast milk, milk, or any other food in a microwave. Microwaves heat food unevenly, and can create pockets of high heat. This can increase the risk of burns — as well as increase the migration of plastic particles from the bottle or food container into the food. Don’t heat your baby’s milk, formula, or food in a microwave.
- Many parents heat water for formula in electric kettles. Avoid electric kettles made of plastic. Plastic kettles can shed high levels of microplastics. Instead, use a metal kettle or pot on the stovetop to heat your water, or choose a glass electric kettle.
- There is no evidence for microplastics in breast milk, but breast milk may be another source of plastic exposure. Breast pumps are largely made of plastic, especially the milk-contact areas (tubes and bags). Many people feed their babies breast milk from plastic bottles, and that breast milk is often reheated before feeding. These practices can introduce microplastics into breast milk.
- If possible, use glass bottles for feeding your baby.