Our modern world is literally filled with plastic: we not only deal with plastic objects on a daily basis, we also spread the substances in our environment. It becomes dangerous when wind, current and UV light break down the plastic into microfine particles that get into the smallest opening. Such particles have already been detected in animal and human tissue. Now the first evidence of human blood has been found.
Plastic particles have toxic effects on cells
Dutch researchers have found polyethylene, polyethylene terephthalate and polymers of styrene in human blood. The average amount was about one teaspoon per 1,000 liters of liquid. The particles probably entered there through the mucous membrane, through inhalation and/or ingestion. In the air, the plastic particles are only about 1 nanometer to 20 micrometers in size, nobody notices. Other studies have already shown that plastic particles have a toxic effect on cells, causing them to change shape.
In mice, the substances have penetrated the blood-brain barrier, raised cholesterol levels and contributed to heart disease. However, it has not been clarified exactly what the particles do in human blood, nor whether and how they subsequently end up in tissues and organs. The Dutch now want to investigate this. The micromaterials cause aneurysms in fish and impair cognitive abilities in hermit crabs. So there are more than enough warning signs.
Our lifestream contains plastic«
The blood test was performed on 22 healthy study participants. The researchers focused on 5 different polymers that serve as building blocks of plastic. “We have now proven that our bloodstream, so to speak, our lifestream, contains plastic,” says Heather Leslie of VU University Amsterdam. And study author Marja Lamoree adds: “This dataset is the first of its kind and needs to be expanded to understand how widespread plastic pollution is in the human body and how harmful it can be. With these insights, we can determine whether exposure to plastic particles poses a threat to public health.” 
Source: newatlas.com