Air Pollutants, Metals Are Reaching The Placenta, Study Finds

TUESDAY, Sept. 29, 2020 (HealthDay News) -- Metals and other air pollutants have been found in the placentas of new mothers, which means such pollutants may be able to reach the fetus, researchers report.

"Our study for the first time shows that inhaled carbon particulate matter in air pollution travels in the blood stream, and is taken up by important cells in the placenta. We hope that this information will encourage policy makers to reduce road traffic emissions," said lead author Dr. Jonathan Grigg, a professor of pediatric respiratory and environmental medicine at Queen Mary University of London.

His team analyzed placentas donated by 15 healthy women in London who had just given birth. Black particles that closely resembled particulate air pollution were found in an average of 1% of cells in all 15 placentas.

Most of the particles were carbon-based. But there were also trace amounts of metals, including silica, phosphorus, calcium, iron and chromium, and more rarely, titanium, cobalt, zinc and cerium.

Many of the metals are associated with vehicle-emitted air pollution from fossil fuel combustion and brake wear, according to the study published recently in the journal Science of The Total Environment.

Co-author Norrice Liu said there had been a known link between maternal exposure to high pollution levels and problems with the fetus, including low birthweight.

"We have thought for a while that maternal inhalation could potentially result in pollution particles traveling to the placenta once inhaled," added Lisa Miyashita, a postdoctoral research assistant. "However, there are many defense mechanisms in the lung that prevent foreign particles from traveling elsewhere, so it was surprising to identify these particles in the placental cells from all 15 of our participants."

More information

The March of Dimes has more on air pollution and pregnancy.