Tainted Claims about “Agglomerated” Corks

A recent article in Wine Industry Insight titled “Micro-Agglomerates: 350 Million Illegal Corks Per Year?” reports: “Agglomerated cork manufacturers and importers are facing scrutiny from two major federal agencies over health concerns about the plastic used to bind bits of cork glued together. The concern is that chemicals in the binding plastic can leach into wine.” 

But a closer look at the issue indicates that these agencies are not focused on the corks, there’s nothing illegal about them, and safety concerns are unwarranted.

The two agencies allegedly interested in the issue are the U.S. Environmental Protection Agency (EPA) and the Food and Drug Administration (FDA). The chemical in question, toluene diisocyanate or TDI, Wine Industry Insight notes, is “listed as a potential carcinogen” with the International Agency for Research on Cancer (IARC) and the National Toxicology Program (NTP).

This sounds scary, but there are many reasons why no one should be alarmed about the closures or the chemical involved. But before going into that, we should be clear as to what the agencies are doing in regard to the corks.

According to an EPA press release, the agency has proposed a rule that would require manufactures to notify the agency if a consumer product they are making will contain more than 0.1 percent of TDI by weight. The EPA does not mention scrutiny of corks that may contain TDI. It’s very possible that these corks don’t contain that much TDI and would not even be subject to this proposed rule.

Nor is the FDA really scrutinizing the issue. Instead, the agency received letter from an outside party asking questions about related FDA law. Wine Industry Insight has posted a link to a letter from the FDA responding to that party, but the name of the party asking questions is either blanked out or never included. But Wine Industry Insight points out that it was an association that represents competitors of agglomerated cork producers—a synthetic cork association—who filed the petition. It notes:

“Competition is fierce for the low-end market which is why a synthetic cork association blew the TDI whistle on agglomerates in a letter to the FDA.”

Obviously, competitors have an interest in making this an issue, but FDA isn’t taking the bait. FDA has authority to regulate “food additives” that might pose a threat to public health and that includes chemicals that might migrate from packaging into food. In its cryptic, bureaucratically written letter, FDA is basically indicating that they have data showing there is no detectable migration of TDI into the wine for the closures currently on the market. Otherwise, they’d be regulating now, but they’re not.

So much for “federal scrutiny.” There really isn’t much because there’s no good reason for it.

It may be true that the International Agency for Research on Cancer and the National Toxicology Program have classified TDI as a potential carcinogen, but that does not mean the chemical poses much of any risk on consumer products. Such classifications only sound scary, but as I have noted before, classifications do not mean the chemical poses any risk in current uses and exposure levels. Remember, it’s the dose that makes the poison. And traces of chemicals in consumer products are too low to matter.

In this case, these agencies give a higher (allegedly more “dangerous”) ranking to pickled vegetables as well as chemicals that form naturally in foods like coffee and even broccoli than they do to TDI.

So, if you open a bottle and see one of these corks, be happy because they are an excellent tool for keeping your wine in good and tasty condition. In fact, I take a keen interest in this issue because, as someone who both loves wine and innovation, I LOVE THESE CORKS! I learned first-hand about them this past summer at a visit to the facility of one of these cork manufacturers—DIAM—who make these so-called “agglomerated corks.”

Basically, rather than simply cutting the bark off of trees and punching out the closures from the cork, DIAM grinds up the cork using more of the tree bark and leaving less waste. Then they clean it and mix the cork grinds with micro-granules that can precisely control how much air goes in and out of the bottle. Not only does this process clean out contaminants such as bacteria that can destroy the wine, it makes a consistent product so winemakers will know exactly how much air the wine in the bottle will receive. And DIAM makes several different grades of cork, meaning some allow more oxygen and some less, so winemakers can select the perfect cork for each type of wine they sell. What a marvelous innovation!

Several wines I buy use these corks and I appreciate their ability to help keep the wine fresh and tasty. Every time I open a bottle that doesn’t use these corks and experience cork taint, I wonder why they used inferior corks for their wine. What a waste!