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By Enrico Liva, N.D., RPh As the public and the professional community make greater use of natural products for general wellness, prevention, and the treatment of disease, the quality assurance of natural products has received greater scrutiny. It is important to know that the brunt of that scrutiny ultimately falls upon the commercial natural products testing laboratory. Manufacturers make product and distributors sell those products. The company that encapsulates or tablets the product is the last one to verify quality assurance before the product gets to the consumer. The only resource the encapsulating or tableting company has to prove the veracity of the product is to use an in-house lab or a commercial contract lab that tests natural products. The bad news is that the commercial natural products contract lab industry is completely unregulated. The good news is having a good working knowledge of laboratory testing and knowing what questions to ask and when, greatly increases your chances of getting accurate results using ethical and scientifically valid methods of testing.
You cab start a lab in your basement or garage, with poorly trained personnel and testing equipment that is poorly maintained. A nice brochure, a good marketing campaign and reasonable prices may be all it takes to get a foothold in the market place. No license is necessary to open a lab. No inspection is required by any government agency. There is no requirement to follow any set of rules, guidelines or quality standards. In short, each lab can do as they please.
The unfortunate news in this laboratory industry is a phenomenon called dry labbing. This is where a lab claims to actually perform the requested test but it really does not. They make up the desired result and give it to the customer. The customer has no clue the test was never performed. It is important to know about dry labbing and how to read a laboratory test (particularly if you are an encapsulating or tableting manufacturer), because some results are scientifically impossible to obtain. Dry labbing is probably not wide spread, but it does occur. If you are the buyer of lab services testing natural products or you scrutinize lab test data, it is important to know how to discern what is scientifically valid verses accepting a lab result at face value.
Some manufacturers claim that their products are tested by FDA certified labs. THE FDA does not certify labs or manufacturing operations. They do inspect labs that are testing pharmaceuticals and over the counter drugs (OTC's), but they do not inspect contract labs testing natural products. If a lab is set up to test pharmaceuticals, OTC's, and natural products, one could make the assumption that the same level of quality and rigor applied to the drug side of the lab carries over to the natural products division. However, when FDA inspects such a lab, they focus their attention on the pharmaceutical and OTC drug side and ignore the natural products side.
GLP stands for good laboratory practices. This is a set of guidelines that if followed will go a long way to assure overall quality practices in a lab. Labs are not required to follow them. Some do, some don't, and all of them should. If a lab does, they can be independently audited for compliance with GLP's. Successful completion of an independent GLP audit is one way to gain confidence in a lab.
Let's make the assumption that a lab has adequately trained personnel, well-maintained instruments and chemicals, follows GLP's, and successfully passes a GLP audit. The most important and major factor determining accurate lab results is the method used to test the product. The method is like a recipe. It governs sample preparation, chemicals used, instrumentation, timing, etc. One of the major problems in the natural products testing industry is the fact that there are very few universally accepted proven methods for all labs to use. Labs make up their own methods or use methods provided by the maker of the product or industry groups. While this is not necessarily always bad, it makes for the possibility of a huge discrepancy in results coming from various labs. The FDA and private groups are working toward method standardization, but this is not going to happen soon. In the meantime, it is up to the person requesting the test to scrutinize the scientific validity of the method the lab will use.
Assuming we have a scientifically valid method, obtaining an accurate lab result is equally dependant upon the reference standard that is used to test the sample against. A lab can have a great method and use a poor standard, which produces an inaccurate result, either high or low. Ideally a lab would only buy guarantee potency reference standards. The information accompanying the standard should state the percentage of purity and identify the impurities. Upon receipt of the standard, the lab would have a valid method in place to test and verify the potency of the standard. This is necessary because many commercially available reference standards vary in potency despite claiming a specific potency. Once the potency is verified, the standard should be stored adequately, an expiration date assigned and a schedule of testing instituted to verify continued potency. It is critical to inquire about the standard used to test natural product. Failure to do so may lead to an unacceptable, inaccurate result.
Once a testing method is developed, it has to be validated. Validation is the proof that a method is suitable for its purposes, is reproducible and shows that it is able to accurately determine the level(s) of analyses of interest in the product. According to the FDA, all products sold to consumers (pharmaceutical and nutritional) must meet label claim. The FDA position on validation is that any method used to determine if a product meets label claims must be validated. The FDA, USP and other scientific groups have published guidelines for validating a method. If a contract lab uses an in house method (a method they developed) or a method from another source, it should validated following either FDA guidelines or another reputable guideline. If the method used has not been validated, it greatly increases the likelihood of obtaining inaccurate results.
In choosing a laboratory, it is important that they meet some of the following criteria: 1) The lab should follow GLP's. 2) The lab should have successfully passed an independent audit for GLP's, following good methods that have been validated using the FDA validation guidelines or another acceptable guideline. 3) They should buy guaranteed potency standards, and test them to verify potency.
The majority of Hypericum extract on the market is standardized to 0.3% Hypericin. The most widely used method to test the Hypericin level is an Ultra Violet Spectrophotometric or UV method. UV Method: This method has been more or less accepted as the industry standard for quality assurance testing of Hypericum extract 0.3%. Essentially this method checks for a certain color (Hypericins fluoresce red) at a specific wavelength and does not distinguish total Hypericin content. The method is woefully inadequate for 3 reasons. First, it does not guarantee you have the right plant. Only microscopic examination of the plant or TLC (thin layer chromatography) will assure correct genus and species. Second, you could easily manipulate this test with very poor quality Hypericin extract and spiking it with the correct amount of red dye. Third, in addition to Hypericin(s) being counted by the UV method there are other substitutes in the plant material that get counted along with it, thus inflating the value of the total Hypericin count. The method cannot distinguish between Hypericin and these other similar substances.(1) HPLC Method: This method also does not completely authenticate genus and species but comes very close, because it does check specifically for Hypericin, Pseudohypericin and other Hypericins found in Hypericum perforatum. The total Hypericin yield via HPLC is 0.2%-0.25% vs. the inflated 0.3% Hypericin claim for the UV method. It is scientifically possible to fool the HPLC method, but it's difficult and not really worth the time, energy, and trouble to do so. To authenticate this plant and its potency, a TLC fingerprint and HPLC assay would be performed. This would leave little or no room for poor quality raw material to slip by. In view of the fact that many contract manufacturers might not foot the bill for both tests, the HPLC assay should be performed at the very least. The UV method should pass into oblivion.
This fairly popular plant medicine has a similar quality assurance dilemma as Hypericum perforatum. Boswellia extract on the market is standardized to 60-80% Boswellic acids. The most widely used method to test the Boswellic acids is titration for organic acids. Titration method: This method does not test for specific Boswellic acids at all, only organic acids. The raw material can easily be manipulated and spiked (with some organic acid) to pass, just like the Hypericum situation. It gives no real assurance of potency or correct plant genus and species. HPLC Method: An HPLC method does exist that quantitates four specific Boswellic acids; beta Boswellic Acid, Acetyl-Beta Boswellic Acid, 11-Keto-Beta Boswellic Acid, and Acetyl-11-Keto-Beta Boswellic Acid. The total Boswellic acid content of raw material is usually around 25%. This is much less than the stated claim of 60-80% for the titration method. To authenticate this plant and its potency, a TLC fingerprint and the HPLC assay for the four stated Boswellic acids would pretty much make it bulletproof. However, the HPLC assay may suffice as the four Boswellic acids are specific enough to the genus and species that it makes the TLC identification much less warranted. As can be seen, regulation and validation of laboratory test methods is an arduous and difficult task. Finding a nutritional supplier that is dedicated and committed to finding honest laboratories, and producing high quality supplements is of utmost importance when choosing a nutritional supplier.
• Kurth PhD, Herman, Spreemann PhD, Ralf. Phytochemical Characterization of Various St. John's Wort Extracts. Advances In Therapy. Vol.15 #2, march/April 1998, pg. 117-128.
Whew!! Definitely do not buy cheap supplements. They couldn't possibly be doing all this and make a profit, and I'm sure they aren't in this business to not make money. The thing that strikes me is that honest manufacturers could be duped by the testing lab, either intentionally or not. Don't take chance. Only take verified, quality supplements that are guaranteed authentic in all ways.
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