Study Finds Microplastics in Every Tested Human Placenta

University of New Mexico Health Sciences researchers have used a new analytical tool to measure the microplastics present in human placentas.

A team led by Matthew Campen, PhD, Regents’ professor in the UNM Department of Pharmaceutical Sciences, reported finding microplastics in all 62 of the placenta samples tested, with concentrations ranging from 6.5 to 790 micrograms per gram of tissue. The study was published in the journal Toxicological Sciences.

Although those numbers may seem small (a microgram is a millionth of a gram), Campen is worried about the health effects of a steadily rising volume of microplastics in the environment.

Used Pyrolysis to Catch Gas Emissions of Different Plastics

“If we’re seeing effects on placentas, then all mammalian life on this planet could be impacted. That’s not good,” says Matthew Campen, PhD, Regents’ professor in the UNM Department of Pharmaceutical Sciences.

For toxicologists, “dose makes the poison,” he said. “If the dose keeps going up, we start to worry. If we’re seeing effects on placentas, then all mammalian life on this planet could be impacted. That’s not good.”

In the study, Campen and his team, partnering with colleagues at the Baylor College of Medicine and Oklahoma State University, analyzed donated placenta tissue. In a process called saponification, they chemically treated the samples to “digest” the fat and proteins into a kind of soap.

They then spun each sample in an ultracentrifuge, leaving a small plastic clump at the bottom of a tube. Next, using a technique called pyrolysis, they placed the plastic pellet in a metal cup and heated it to 600 degrees Celsius. Then they captured gas emissions as different types of plastic combusted at specific temperatures.

“The gas emission goes into a mass spectrometer and gives you a specific fingerprint,” Campen said. “It’s really cool.”

Polyethylene was the Most Abundant Polymer Found:

The researchers found the most abundant polymer in placental tissue was polyethylene, which is used to make plastic bags and bottles. It accounted for 54% of the total plastics. Polyvinyl chloride and nylon each represented about 10% of the total, with the remainder consisting of nine other polymers.

Marcus Garcia, PharmD, a postdoctoral fellow in Campen’s lab, said that until now, it has been difficult to quantify how much microplastic is present in human tissue. Typically, researchers would simply count the number of particles visible under a microscope, even though some particles are too small to be seen.

Source: University of New Mexico Health Sciences/specialchem