EDITORIAL: Imperfectly Acceptable?

As packaging professionals, you’ve all gotten used to striving for the flawless package. But just how perfect does your package need to be? Could it contain pinholes or channels and still be considered safe and effective?

John Spitzley is awaiting these answers, as are other medical device packaging professionals. Recently retired from Medtronic after nearly 32 years, Spitzley says that in the past, medical device packagers have always “aimed for impermeability,” breathable packages notwithstanding. But he has suspected that “some seal anomalies may be OK.”

To provide some answers, the Sterile Barrier Package Integrity Task Group of IoPP’s Medical Device Packaging Committee continues its work. As we report in this issue (on page 12) and in others, the group is evaluating an alternative microbial challenge test method that involves the aseptic injection of sterile agar into a sealed and sterilized tray and then bombarding that package with microbes. To date, tests have shown that the injection itself does not introduce contamination. The group is now gearing up to present its method to ASTM Working Group F-02 as a standard. After raising funds, the group will then study what size breach allows microbial penetration.

The answers could change everything, says Spitzley. This study could “quantify what we are looking for,” he says. “One possible outcome would be to identify the level of sensitivity that we need to test to, which may be significantly below the current parameters.”

This test, however, is not presented as an alternative to physical challenge tests, points out Laura Bix, assistant professor, Michigan State University School of Packaging, who also serves as task group leader of the Sterile Barrier Package Integrity Task Group. “Rather than replacing physical tests, this test is meant to inform them,” she says.

We asked Bix whether the test would obviate the need for more-sensitive physical tests, some of which we describe in this month’s feature, “Simplifying Testing,” on page 28. “As physical tests become more and more sensitive, packaging engineers find more defects and throw out more packages, because they need to err on the side of caution,” she says. “And they should continue to err on the side of caution. [The work of the sterile barrier package integrity task group] approaches that question with science.”

In fact, Spitzley hopes that medical device packagers will start to put some of the newest physical challenge testing systems to use. “Just because the older technologies didn’t detect package problems doesn’t mean that there weren’t any,” he says. “The new systems need to be applied.” He mentions systems from PTI, Mocon, and T.M. Electronics.

Bix does say that the proposed microbial challenge test “has shown the promise of reducing the false-positives that were associated with the whole package microbial challenges of the past.” Reducing false-positives could reduce product and package waste.

In the end, the proposed new microbial challenge test and the more-sensitive physical tests may work in concert to yield more data about package performance. A simplified package testing program? Maybe not. But a better designed package, with appropriate investments in time and money? Maybe so.

Daphne Allen

For more information on the Sterile Barrier Package Integrity Task Group of IoPP’s Medical Device Packaging Committee, contact John Spitzley, cochair of IoPP’s Medical Device Packaging Committee, who is now a consultant to the medical device packaging industry. E-mail him at johnspitzley@comcast.net or call him at 651/343-3795. You can also contact Curt Larsen of DuPont Medical Packaging (curt.l.larson@usa.dupont.com), the committee’s other cochair.

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