Medical Infusion Bags Can Release Microplastics Into the Bloodstream, Research Finds

Microplastics are entering the human body through the ingesting of seafood, drinking water and even by inhaling particles in the air. These plastic particles have been detected in the human gut, blood, lungs and brain.

Now, a team of researchers has found another potential pathway for microplastics to enter the bloodstream: medical bags used for infusions. According to a new study published in Environment & Health, a single 8.4 ounce (250 milliliter) medical infusion bag could release 7,500 microplastic particles — sized 1 to 62 micrometers long — into a person’s blood.

Medical infusion bags can be used to provide intravenous (IV) fluids such as water, nutrients, electrolytes or medicine, as the American Chemical Society reported. Previous research from the 1970s found that these infusion bags may contain solid particles, which prompted researchers of the newly published study to investigate whether these particles could be microplastics. 

Medical infusion bags are typically made from polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), thermoplastic elastomers(TPE) or ethylene vinyl acetate (EVA). PP is one of the most common materials, because it seals well, holds up to impacts, is resistant to chemical corrosion and is transparent.

To determine whether medical infusion bags may release microplastics, researchers tested two different brands of commercial infusion bags, both made from PP, containing IV saline solutions. They allowed each bag to drip from an infusion tube into separate glass beakers, which were covered with aluminum foil to prevent outside particles from interfering.

After collecting the liquid, the team filtered and condensed the samples in order to count and analyze the plastic particles detected under a microscope. They used this total to then estimate the amount of microplastics for each entire medical infusion bag.

The samples collected from both brands included PP microplastics, and based on the analysis, the team determined that one bag could release around 7,500 microplastic particles into the bloodstream during an infusion. When more fluids are needed to treat ailments such as dehydration or during procedures such as abdominal surgery, this total could increase substantially.

Heat illness, nausea, diarrhea and similar instances that require IV fluids could lead to a release of around 24,375 to 30,000 microplastics. With severe dehydration requiring about 4.2 to 5.6 liters of water infusion for a person weighing an average 60 to 80 kilograms (132 to 176 pounds), medical infusion bags could release 31,500 to 42,000 microplastic particles into the blood, the study determined. These findings become more concerning as the world continues to break heat records and risk of heat-related illnesses and deaths rises.

In some cases, such as an abdominal surgery, higher IV fluid requirements mean that as much as 52,500 microplastics could be released into a patient’s bloodstream.

The study authors noted that additional analyses will need to investigate any differences in microplastic presence among a wider range of brands, different batches, batches made in different facilities, bags made from different materials or even differing qualities of PP, storage conditions and other factors. Additionally, more research is needed to further evaluate the health risks of microplastics.

To limit the amount of microplastic breakdown, the authors wrote that temperature and UV light exposure should be highly considered when storing the medical bags, as higher temperatures and more light exposure can degrade the PP material.

“Potentially effective measures include the use of highly efficient micrometer- or submicrometer-level filtration systems during intravenous infusion and enhanced monitoring across the medical device and pharmaceutical supply chain to meet stringent safety standards,” the authors concluded. “Additionally, innovative infusion system designs using materials resistant to MP shedding and optimized closed systems may significantly minimize external contamination.”