The dietary supplement industry should be concerned about the practice called "dry labbing," as there are probably more than a handful of laboratories operating under these types of practices. Not all dry labs will be operating as blatantly as the lab that was identified in the recent Dateline NBC segment covering that topic. Some labs may in fact be performing selective dry labbing, which means they will do testing on some samples, and not on others, which would make it much more difficult to prove.

When a company uses an independent third-party analytical lab for testing dietary supplement products, the third-party lab must also be qualified to provide those services under GMPs (good manufacturing practice).

A few best practices can help companies ensure they are working with the highest quality third-party contract analytical laboratories.

First, qualify any contract laboratories before sending samples and relying on the results they provide. It is a good idea to have a standard operating procedure (SOP) for "Qualifying Independent Contract Testing Laboratories." Consider providing a checklist for performing due diligence on a laboratory before it is "qualified" for use.

Next, qualify more than one analytical laboratory. Not only is it doubtful one laboratory could meet all of a company's needs, it is also better to use laboratories based upon their analytical expertise.

Then, sign a contract or agreement with the lab defining the relationship. This establishes ground rules and expectations with the third-party lab, which not only makes good business sense, but also is an important part of GMPs.

After that, visit, audit and inspect those contracted labo

ratories. Contract laboratories performing analytical testing services for dietary supplement manufacturers are in fact a part of the GMP process, which makes them fully accountable for being GMP compliant. Since contract laboratories are accountable for GMPs, the companies using the services of contract laboratories should visit, audit and inspect their labs ensure they are compliant.

Also consider what information and specifications are detailed when sending samples to independent laboratories for testing. Bear in mind it is not feasible to provide the lab with no details about the specifications for the sample. This would make it difficult for the lab to perform proper analytical testing without have some idea what the concentration range of the analyte (compound of interest) actually is. However, as an example, if the product to be tested contains 75 mg of caffeine per capsule, instead of stating the expectation is 75 mg/capsule, consider defining the expectation as somewhere between 25 mg and 150 mg per capsule. Not providing the laboratory with the exact specification makes it difficult for the lab to fabricate an expected value.

Finally, companies should  send challenge samples to all the contract laboratories they use. Challenge samples are also known as "dummy" samples, which have been made to misrepresent what you are telling them has been sent. For example, send the laboratory a sample of vitamin C capsules, and ask that they be tested for caffeine. If the laboratory reports there was no caffeine, a company is probably in good shape. The practice of sending challenge samples to  laboratories should be done with regularity. Challenge samples can also be used to perform routine check ups on the proficiency of the laboratories. For example, certified reference materials (CRMs) could be purchased from the National Institute of Standards and Technology (NIST), where they have been precisely measured and reported the values for various analytes in botanical matrix samples, such as spinach. Sending labs such proficiency samples can help determine how accurate their results are as compared to well-established values in CRM materials.

If companies in the dietary supplement industry using contract testing labs were to follow these basic tips, it would be difficult to operate a dry lab without getting caught. Will the elimination of dry labbing solve all of the quality control issues voiced at industry meetings? Not entirely; but, it will be one big step in the right direction by eliminating the "plausible deniability" blanket that dry labs most certainly provide companies knowingly or unknowingly using these labs.

Frank Jaksch is the president, CEO and co-founder of ChromaDex Inc. Prior to starting ChromaDex, Jaksch was with Phenomenex, an analytical chemistry consumables company, where he managed the international subsidiary and business development divisions. He is the co-author of "The Handbook of Analytical Methods for Dietary Supplements," which was published by the American Pharmacists Association in 2005.

Learn more about working with thrid-party contract manufacturers in INSIDER's Contract Manufacturing Content Library.