CHEMICAL COCKTAIL

Newborn babies seem so pure. Their miniature toes have never encountered the ground. Their gummy mouths eagerly seek, for the first time, colostrum and then milk.

But they have been connected to the outer world for months via the placenta that bonds them to their mothers. Today, that world is replete with minuscule pieces of plastic, and this year a scientific paper reported the discovery of microplastics in the placentas of four babies born in Rome. Just a fraction of a millimetre long, the particles were on the babies’ side of the placenta as well as the mothers’. The placenta is the interface between mother and baby that provides nutrients to the fetus and removes its waste.

The likely sources of the microplastics were revealed by their pigments: paints, adhesives, plasters, cosmetics and personal-care products. “Every time scientists have looked for microplastics in people, they’ve found them, including in faeces,” says Professor Sally Gaw, an environmental scientist at the University of Canterbury. “If they’re in the placenta, they will have come from the mother’s blood.”

The authors of the paper, titled Plasticenta: First evidence of microplastics in human placenta, suspect the particles entered the mothers’ bloodstream either through the lungs or intestines. They may have slipped between cells that line these organs or been engulfed by immune cells at the lining. In either case, another type of immune cell probably then consumed them and ejected them into the bloodstream.

“Very small particles – less than 10 to 20 microns – can cross from the lungs into the bloodstream. They can enter via the gut, too, and potentially trigger an immune response,” says Gaw. “In lungs, there is evidence of damage and inflammation. Their effect on human health is very much an emerging area and not a lot is known yet. It’s hard to study. But we know that lungs don’t like tiny particles of any type, even cotton or smoke.”

Microplastics were found in the placentas