Environmental particulates have been plaguing humans for some time now. Air pollutants have been implicated in many health issues, lowering immune strength and hastening disease, possibly even affecting social cognition and behavior, including violent behavior (h/t cawfeemug for the link).
Earlier this month, news broke that nearly half of all American adults have been exposed to lead over the course of their lifetimes, to the extent of an accumulated loss of over 83 billion IQ points. (This averages to about 2-3 points per person, with those on the high end of exposure suffering a loss of up approximately 7 points.) Most of the persons would have been affected before lead was phased out, with exposure occuring in the ‘60s and ‘70s. (“90% of children born in the US between 1950 and 1981 had blood-lead levels higher than the CDC threshold,” the Guardian reported.) The primary culprit seems to have been leaded gasoline. The substance, too, has been linked to violent criminal behavior.
Now, the Guardian relates that microplastics have been detected in human bloodstreams for the first time, in 77% of those tested.
Microplastics range in size; the researchers state that “[i]n the literature, microplastic is often defined as plastic particles up to 5 mm in dimensions with no defined lower size limit.” The focus of this study was of particles equal to or greater than 700 nanometers. As the study notes, most “capillaries are typically only 5-8 µm in diameter,” so a possible danger would arise from the particles occluding these crucial passages.
The scientists analysed blood samples from 22 anonymous donors, all healthy adults and found plastic particles in 17. Half the samples contained PET plastic, which is commonly used in drinks bottles, while a third contained polystyrene, used for packaging food and other products. A quarter of the blood samples contained polyethylene, from which plastic carrier bags are made. …
“It is certainly reasonable to be concerned,” [Prof Dick Vethaak, an ecotoxicologist at Vrije Universiteit Amsterdam in the Netherlands], told the Guardian. “The particles are there and are transported throughout the body.” He said previous work had shown that microplastics were 10 times higher in the faeces of babies compared with adults and that babies fed with plastic bottles are swallowing millions of microplastic particles a day. ...
A recent study found that microplastics can latch on to the outer membranes of red blood cells and may limit their ability to transport oxygen. The particles have also been found in the placentas of pregnant women, and in pregnant rats they pass rapidly through the lungs into the hearts, brains and other organs of the foetuses.
An especial concern would be if microplastics could cross the blood-brain barrier. This remains unknown.
The research team went to great lengths to ensure the integrity of results, utilizing glass vials and steel syringe needles to avoid plastic contamination via any collection materials. The study was small, with only 22 participants, but the results are significant and certainly warrant further review. The researchers consider their study “pioneering.”
I’ve read elsewhere that blood collected and stored prior to the end of WWII has some of the cleanest blood levels measurable today (that is, least polluted by particulate matter). It’s entirely possible that we will never be able to make it back to that level of somatic clarity.