What is ‘Medical Grade Plastic’?

We don't typically associate plastic with positivity. Plastic is known for being a prime perpetrator of pollution, namely plastic pollution in our oceans, inland waterways, towns, and cities. According to Surfers Against Sewage, 8 million pieces of plastic find their way into our oceans each day. If that's the case, what is medical-grade plastic, and why do we still use it? Keep reading to explore.

What Is Medical Grade Plastic?

Let's start by answering the question. Medical grade plastic is a material used in, well, medicine, with multiple applications. It's not a one-trick pony, and that's why it's so widely used. Let's get technical - medical-grade plastic is typically made from thermoplastic materials such as polycarbonate, polyethylene, or sometimes custom polymers tailored towards a specific medical device application.

The plastic should meet specific requirements outlined in national and international regulations - an example being the EU regulation 2017/45 (MDR). Technically, that means manufacturers can use any polymeric material as long as it meets the guideline requirements, although, typically, the materials mentioned above are the go-to materials.

Most medical-grade plastics are typically put into three categories:

• Non-implantable - used externally rather than implanted into the body.
• Short-term implantable - this type of plastic can stay in the body for up to a few weeks.
• Long-term implantable - this can stay in the body for months, and sometimes years, at a time. Applications include long-term analgesic administration and joint replacements.

Why Is It Used?

There is yet to be a material more suitable than medical-grade plastic. Most importantly, medical-grade plastic is easy to sterile, and the composition of the material doesn't falter after multiple sterilisation cycles. Infection prevention is of paramount importance within a healthcare setting, something professionals are striving to achieve excellence in, and medical-grade plastic is one of the easier materials to sterilise.

Sterility isn't the only perk - medical-grade plastic has low toxicity and chemical reactivity levels, making it perfect for intravenous devices such as the all-important cannula. Cannulas are typically made from biocompatible polyurethane and must be coated with heparin or something similar to reduce the inflammation response. 

How Is It Used?

Cannulas are not the only application of medical-grade plastic. In theatres, the self-retaining retractor, endoscopic probes, PPE face shields, and prosthetic devices. All of which another type of material wouldn't be suitable. Plastic can be transparent, flexible, and easily adjusted to suit the needs of the procedure.

One of the categories is non-implantation, and that applies to devices such as an MRI or CT scanner - both are made of durable medical-grade plastic. Some medical-grade plastics are single-use, but most, like an MRI scanner, can simply be sterilized, ready for the next patient with minimal infection transmission risk. It's devices such as a cannula that go straight in the sharps bin as a single-use device.

It's unlikely that new materials will replace plastic anytime soon. Not only is it durable and easy to sterile, but it's also cost-effective. Plastic is a cheap material, and there's a somewhat unlimited supply of it. There are so many applications of medical-grade plastic that it would be hard to abolish it entirely.