The Use of Color in Medical Devices: FDA's Regulatory Authority Is Less Than Crystal Clear

By Keller and Heckman LLP’s Packaging Practice Group

The scenario: A child in an emergency room needs to have blood drawn immediately so that her doctors can run tests necessary to save her life. A nurse must quickly distinguish the proper 22 gauge needle from the 20 gauge needle, which is too large for the child's small veins. It's not likely that the nurse will be able to eyeball the difference; a 22 gauge needle has a diameter of 0.0275 inches while a 20 gauge needle has a diameter of 0.0375.

Once the child's blood is collected and sent to the laboratory for analysis, the technician must distinguish between a vial of the child's blood and a vial that also contains the anticoagulant needed to conduct specific critical care tests.

In critical situations like this, medical professionals cannot depend on markings that can be accidentally wiped away. Rather, they rely on color-coded medical devices to save the lives of their patients. Other medical devices employ colors for other purposes. While the reason for using color in a product can be unique to the specific medical device--such as changing the appearance of a person's eye color with a colored contact lens--other uses of color can be attributed to the manufacturer's desire to enhance the marketability of its product. For instance, condom manufacturers have indicated that certain regions of the world prefer prophylactics in certain colors.1

Regardless of the reason for the use of color, it is essential that medical device manufacturers use colorants that have a proper regulatory status for the intended use of the products. This article briefly discusses the U.S. Food and Drug Administration's (FDA) jurisdiction to regulate colorants in medical devices, and the regulatory considerations of selecting a color to add to a medical device.

As noted in a previous PackagingLaw.com article, "The Use of Colorants in Packaging Applications: An Overview" (see below for link), Congress amended the Federal Food Drug and Cosmetics Act (FD Act) in 1960 to create a class of substances identified as "color additives."2 As amended, the FD Act defines a color additive as a material that:

• (A) is a dye, pigment, or other substance made by a process of synthesis or similar artifice, or extracted, isolated, or otherwise derived, with or without intermediate or final change of identity, from a vegetable, animal, mineral, or other source and
• (B) when added or applied to a food or cosmetic, or to the human body or any part thereof, is capable ... of imparting color thereto.

            21 U.S.C. § 321(t)(1).

It is significant to note that the "color additive" definition excludes substances added to "medical devices" to impart color. This suggests that colorants in medical devices that do not otherwise satisfy the "color additive" definition are not subject to FDA regulation as color additives and do not need FDA premarket approval.

FDA, however, reads the color additive definition in a different, and more creative way. FDA asserts that the phrase, "capable ... of imparting color," implies that a colorant is a color additive if "it can impart color when it is added or applied to the human body, even though it cannot impart color to the body when it is used in a device."3

FDA has stated its belief that Congress, in subjecting some colorants in medical devices to regulation as color additives, was concerned with the potential toxicity of the chemicals used as colorants, not with their effectiveness in coloring the body tissues with which they came into contact. The agency seems untroubled by the fact that the legislative histories of the Medical Device Amendments of 1976 and the Color Additive Amendments of 1960 provide no support for this position.

In spite of FDA's creative interpretation, Section 721(a) of the FD Act provides that colorants in medical devices are exempt from the need for a color additive regulation unless "the color additive comes in direct contact with the body of man or other animals for a significant period of time." FDA has reserved for itself the authority to assess the "significance" of the contact with the body in determining whether to require premarket clearance of a colorant used in a medical device.

For colorants used in or on devices that are eligible for clearance under Section 510(k) of the FD Act, as well as in devices that are exempt from notification, FDA has chosen not to enforce the color additive requirements. In fact, there is no mechanism for colorant manufacturers to obtain independent FDA review of colorants for use in all medical devices. Instead, the agency requires colorants for medical devices to be the subject of Color Additive Regulations only when used in Class III devices requiring Pre-market Approval Applications. The applicable Color Additive Regulations are drafted narrowly to cover particular medical devices. Examples of such products are certain types of sutures, extended-wear soft contact lenses, and bone cement.

In situations where a preapproved color additive is unnecessary, many manufacturers prefer to use colorants that have a favorable food-contact status. Such a status, however, does not mean that a material is necessarily suitable for use in medical devices. Instead, it is a single piece of information that may be considered by FDA as part of its review of the safety of the device itself. There are a number of ways to establish a suitable food-contact status for substances, including colorants, as detailed in "Fathoming Food Packaging Regulation Revisited," elsewhere on PackagingLaw.com.

Rather than repeatedly submitting the same formulation and safety information to FDA, some colorant manufacturers assist their customers while advancing FDA's review of medical device applications by submitting and maintaining Device Master Files (MAF). In addition to including general toxicological information on the colorant, some manufacturers conduct biological reactivity tests on their products and include the test results in the MAF. Information in an MAF is kept confidential.

Colorants will continue to be an important characteristic of many medical devices, and, consequently, it is important that colorants be suitable for specific devices. Although there is disagreement about the definition of a color additive, it is recognized that only medical devices that have significant contact with the body of a man or animal need to use colorants cleared under a specific color additive regulation. Manufacturers of less-invasive medical devices, typically prefer to use colorants that have a favorable status under FDA's regulations for food-contact substances.

FOOTNOTES

1See www.dw-world.de/english/0,3367,1922_A_344778,00.html.

2See Color Additive Amendments of 1960, PL 86-618 (S. 2197); 74 Stat. 397.

3Letter from Thomas Scarlett, Chief Counsel, Food and Drug Administration to John B. Dubeck (Keller and Heckman) (February 15, 1983).