Factsheets

Vinyl in Medical Applications: Unique Characteristics Help Save Lives

For more than 50 years, vinyl's performance and protectiveness have made it a critical material in such health care products and procedures as blood and intravenous bags, kidney dialysis and blood transfusions, cardiac catheters and endotracheal tubes.  These products are regulated for safety by the U.S. Food and Drug Administration (FDA).
Vinyl has a number of characteristics that together make it uniquely suited to medical use:

  • It is optically clearer than many alternatives.
  • It is kink-resistant.  Alternatives frequently kink when bent to angles of 90 degrees or more, which can cut off the flow of blood or vital fluids to a patient if left undetected for any length of time.
  • It resists “necking down” – that is, constricting when pulled.  Vinyl alternatives can neck down when inadvertently stretched, which can result in a changed inner tubing diameter that affects the fluid delivery rate.
  • Medical kits made of vinyl are factory assembled using a technique known as solvent cementing, in which tubing is locked to its connectors and ports by a solvent that evaporates after application.  Most PVC substitutes cannot be bonded this way.  If joints yank loose and leaks occur, patients can be exposed to flow interruptions, and care givers can be exposed to potentially contagious body fluids.

Vinyl medical products can also be steam-sterilized and frozen.  And, they are tough enough to be air-dropped onto a battlefield for use by troops on the move.
Flexibility is a key performance attribute of vinyl medical products, requiring the use of a plasticizer.  Di(2-ethylhexyl) phthalate (DEHP) is the plasticizer most often used (although not the only one available) to make vinyl flexible.  DEHP allows vinyl to be softened and shaped into many designs without cracking or leaking. Without plasticizers such as DEHP, many of the vinyl medical products doctors and nurses use everyday would not exist.
However, because DEHP is not an integral part of the PVC polymer matrix, it can be extracted from vinyl devices that come into contact with fluids such as blood, plasma, and other solutions. The U.S. Food and Drug Administration (FDA) considers this phenomenon when it evaluates medical devices. FDA conducted a safety review of DEHP and found "little or no risk" to most patients receiving the majority of procedures involving DEHP-plasticized medical products.  FDA cautioned doctors and nurses about exposure to phthalates in certain patient populations, such as premature male infants undergoing continuous blood oxygenation therapy.  The agency noted that it had not received reports of harm from such uses of vinyl medical products (widely used for decades) and also cautioned not to forego life-saving procedures using vinyl products, noting “the risks of not doing a needed procedure is far greater than the risk associated with exposure to DEHP."

Disposal

Vinyl medical products can be handled like other medical wastes at the end of their lives, whether that means sterilizing and landfill or incineration.  If they are incinerated, vinyl products are not a unique source of dioxin, which can be created when most things burn, including wood, food and garbage as well as vinyl. 

Dioxin is formed when chlorine or chlorides are present during combustion.  Studies have shown that when burning is well controlled as it is in modern incinerators, very little dioxin is made or emitted.  For example, a 1995 study sponsored by the American Society of Mechanical Engineers (ASME), involving the analysis of more than 1,900 test results from 169 large-scale commercial incinerator facilities throughout the world, found no relationship between the chlorine content of waste like vinyl and dioxin emissions from combustion processes under real-life conditions. The amount of chlorine or vinyl going into the incinerator is not a reliable indicator of the amount of dioxin coming out. Rather, incinerator design and operation have far more important impacts. However, in uncontrolled burning (e.g., volcanoes, forest fires, old incinerators, backyard burn barrels and accidental building fires), dioxin can be formed in larger amounts.
The best news about dioxin is that emissions to the environment and levels in the environment have been declining for decades, according to the U.S. Environmental Protection Agency.  This has happened even as vinyl production and use have soared. 

Additional Resources

Lifestyle

King Finds Comfort in Colour
April 11, 2008 – The work shown in his sculptor Phillip King's latest exhibition, Living with Colour, is a new departure — in part the result of him discovering a new material to work with, foam PVC.
Learn more...