The authors of the study published in the journal Nature Food exposed each of the best-selling models of polypropylene baby bottles to the preparation procedure recommended by the World Health Organization: sterilizing the bottle, then preparing the formula with a formula. water heated to 70 ° C, to eliminate any dangerous bacteria.
As a result, some bottles release up to 16 million microplastics per liter, and temperature plays an important role.
Thus, if the water for preparing milk is heated to 95 ° C, the amount can rise to 55 million per liter; and go down to just over half a million with 25 ° C water. A 12-month-old baby swallows an average of 1.5 million microplastics every day, according to the researchers who were based in particular on the sales figures of bottles and the volume of milk ingested per day in 48 countries.
“The last thing we want is to overly alarm parents, especially since we don’t have enough information about the potential consequences of microplastics on the health of babies,” commented one of the authors, John Boland, who calls all the same in the Guardian for the precautionary principle.
Some studies show the extent of food contamination with microplastics – notably WWF has estimated that the average person ingests up to 5 grams of plastic each week – the weight of a credit card. But data are lacking on the health impact of this ingestion itself or the chemical risks associated with possible additives.
“It is very possible that (particles) are simply passing very quickly through the body,” noted Oliver Jones, a professor at RMIT University in Melbourne who was not involved in the study, cited by Science. Media Center.
Interestingly, both polypropylene and glass bottles have been particularly highlighted since 2010 in France, when Bisphenol A bottles were banned.
Limit exposure of babies
Despite everything, the authors make recommendations to limit the exposure of babies: rinse the bottles three times with cold sterilized water after sterilization, prepare the milk powder in a non-plastic container before pouring the cooled liquid into the bottle. , do not shake the bottle too much, do not put it in the microwave.
And to heat the water, do not use a plastic electric kettle that releases “a similar number of microplastics”.
The study did not look at glass baby bottles, which although “do not release particles”, are “heavy and breakable” and remain marginal in the market, the authors note.
Given the widespread use of plastic models, “studying the fate and transport of microplastics through the body is our next step”, they told AFP, specifying that they wanted to focus on questions of immunology and of biochemistry linked to the ingestion of micro or even nanoparticles of plastics.