Marlex is the trademarked name for a specific type of plastic that is used in many of C.R. Bard's hernia mesh products. Marlex was never being designed for internal use, as it was known to degrade inside the body as it comes into contact with oxygen. Nevertheless, C.R. Bard has used Marlex in its hernia mesh products since the 1970s. The disintegration of Marlex inside the body has been a centerpiece of hernia mesh lawsuits filed by victims who have been hurt by their implants.
- 1. What is Marlex?
- 2. How Marlex came to be used in hernia mesh
- 3. How Bard's Marlex meshes are defective
- 4. FDA intervention
1. What is Marlex?
Marlex is a trademark name for solid HGX-030-01 polypropylene, a type of plastic used in a wide variety of things from Hula Hoops to plastic bottles. Marlex is made using ethylene and propylene with a catalyst of chromium oxide, and was first created in the 1950s by workers at the Phillips Petroleum Company – now the Chevron Phillips Chemical Company.
What sets Marlex plastic apart from other plastics is the density it can achieve from relatively little pressure. Most other plastics take thousands of pounds of pressure to squeeze them into soft shapes. Marlex plastic only takes a few hundred pounds of pressure to squeeze it into a rigid shape.
2. How Marlex came to be used in hernia mesh
C.R. Bard started using Marlex polypropylene in its hernia mesh products in the 1970s, before the U.S. Food and Drug Administration (FDA) began regulating medical devices in 1976. Because hernia meshes made from Marlex plastic were on the market before 1976, they were “grandfathered” into approval.
Additionally, the regulations that gave the FDA power over medical devices included a loophole that allowed future medical devices that were “substantially similar” to pre-1976 devices to get an expedited approval known as the 510(k) clearance process. Because Marlex hernia meshes were already on the market in 1976, any hernia mesh based on the Marlex model could hit the market quicker through the 510(k) clearance process.
3. How Bard's Marlex meshes are defective
Marlex is a plastic that oxidizes, or deteriorates when it comes into contact with oxygen. Once implanted in a person, a hernia mesh made from Marlex gets surrounded by tissues and blood that contain oxygen. Even when the Marlex is treated with antioxidant additives that slow the oxidization process down, those additives eventually dissipate and leave the Marlex unprotected so it slowly deteriorates.
These chemical traits of Marlex are well known.
In 2005, the makers of Marlex, Chevron Phillips, learned that medical device manufacturer Boston Scientific was shaping Marlex polypropylene into tightly-woven mesh devices for implantation, and that they were making huge profits on it. Shocked that their material was being used for implants that it was never designed for, Chevron Phillips refused to sell Marlex to Boston Scientific at any price.1
Chevron Phillips' refusal to sell Marlex for use in implantable hernia meshes put Boston Scientific in a tough spot: They had to use something “substantially similar” to Marlex to benefit from the expedited 510(k) clearance process, but Marlex suppliers were freezing them from the market to avoid liability for using something so dangerous in a medical implant.2 After numerous failed attempts that brought Boston Scientific to the end of its stockpile of Marlex, the company bought a suspect load of counterfeit Marlex from Chinese suppliers.3
Despite internal testing that indicated the plastic material was probably not actually Marlex, and that it definitely had lower levels of antioxidant materials in it, Boston Scientific began using it to make implantable mesh devices, anyway.4
Lawsuits against Boston Scientific claim that the new material has been used in its mesh products since at least 2014.
Chemical experts have estimated that the mesh devices using this new material, which are designed for life-long implantation, would likely begin to oxidize and deteriorate within a few months.5
4. FDA intervention
While the FDA has not recalled mesh products made from Marlex, they have ordered manufacturers of certain mesh products to stop selling their products in the U.S.6 While this order only impacts implantable mesh products that are used for the transvaginal repair of pelvic organ prolapsed, rather than the entire line of mesh products that use Marlex polypropylene, the order is a move in the right direction.
See Scott Pelley, “Gynecological Mesh: The Medical Device that has 100,000 Women Suing,” CBS News (April 17, 2019).
See note 1.
See note 1.
See note 1.
See note 1.
FDA News Release, “FDA takes action to protect women's health, orders manufacturers of surgical mesh intended for transvaginal repair of pelvic organ prolapse to stop selling all devices,” (April 16, 2019).