HQ Team
June 14, 2023: About 16.2 bits of microplastic are inhaled by humans every hour — that constitutes a credit card for an entire week, according to research published by the American Institute of Physics.
“Millions of tons of these microplastic particles have been found in water, air, and soil,” said author Mohammad S. Islam.“Global microplastic production is surging, and the density of microplastics in the air is increasing significantly.”
“For the first time, in 2022, the studies found microplastics deep in human airways, which raises the concern of serious respiratory health hazards.”
Tiny microplastic debris is generated from the degradation of plastic products, consumer products, tire wear, and industrial breakdown. Global microplastic production is surging, and the density of microplastics in the air is increasing significantly.
Transport behavior
The respirable microplastics can transport in atmospheric air. The transport behavior, migration, and toxicity of microplastics in human airways were never studied.
Australian researchers explored the movement of microplastics with different shapes — spherical, tetrahedral, and cylindrical — and sizes, 1.6, 2.56, and 5.56 microns, and under slow and fast breathing conditions.
Microplastics tended to collect in hot spots in the nasal cavity and oropharynx, or back of the throat.
“The complicated and highly asymmetric anatomical shape of the airway and complex flow behavior in the nasal cavity and oropharynx causes the microplastics to deviate from the flow pathline and deposit in those areas,” said Islam.
“The flow speed, particle inertia, and asymmetric anatomy influence the overall deposition and increase the deposition concentration in the nasal cavities and the oropharynx area.”
Breathing conditions and microplastic size influenced the overall microplastic deposition rate in airways.
Largest particle deposits
An increased flow rate led to less deposition, and the largest, 5.56 micron, microplastics were deposited in the airways more often than their smaller counterparts.
The study highlights the real concern of exposure to and inhalation of microplastics, particularly in areas with high levels of plastic pollution or industrial activity.
The results could help inform targeted drug delivery devices and improve health risk assessment.
Consumable microplastics have been detected in seafood, salt, sugar, honey, milk, and drinking water. The jury is still out on their impact on human health.
