Herbals need better regulation to overcome quality control challenges, say researchers

By Nathan Gray

- Last updated on GMT

Related tags Herbal medicines Herbalism

Implementing better growing and manufacturing processes along with increasing the use of modern analytical techniques and greater international regulation would ‘undoubtedly’ reduce the issues surrounding the quality of herbal extracts, say researchers.

Writing in Complementary Therapies in Medicine​, researchers said that despite the growing popularity of herbal medicines worldwide, there are still many adverse events associated with herbal supplements – which can be attributed to the poor quality of the raw materials or the finished products.

Led by senior author Professor Edzard Ernst of Peninsula Medical School, UK, the research group explained that increases in the usage of herbal medicines worldwide means that these safety issues have become important.

“A large proportion of the adverse events are attributable to the poor quality of the finished products, some resulting from the raw herbal materials that were contaminated,”​ said the researchers.

Ernst and his colleagues warned that issues such as contamination with toxic metals, pesticides residues and microbes, in addition to the rise of adulteration and misidentification mean that greater quality controls are needed for herbals.

“Although the problems are universal, they seem to be more prevalent in Asian countries, especially in China and India, which are the largest producers and users of herbal medicines,”​ reported Ernst and his team.

Quality is key

Ernst and his colleagues explained that there are many factors which influence the quality of herbals products – from the cultivation of medicinal herbs to the final herbal product. These issues can be categorised into ‘external’ and ‘internal’ issues, they said.

External quality problems mainly include contamination, adulteration, and misidentification, they said – adding that such problems can lead to a serious risk of harm to consumers and can pose a serious obstacle to the reliable trade and exporting of such products.

“Heavy metals have been found in herbal medicines with some regularity,”​ they warned. “The three most commonly detected toxic metals are mercury, arsenic, and lead; others include cadmium, copper and thallium.”

The team also warned that instances of herbal medicines adulterated with orthodox drugs and plant materials “have repeatedly been documented.”

“Several pharmaceuticals have been found in herbal medicines, and the incidence of adulteration of commercially available herbal preparation was reported to be 7% in California, 5.5% in New York and 1.23% in Singapore,”​ they noted.

Ernst and his team added that ‘internal’ quality issues can be even more challenging – explaining that the “bewildering variety of phytochemicals”​ produced by some herbs, in addition regional variations in composition caused by a host of environmental factors can lead to important issues of quality.

“A recent analysis of 25 ginseng products found a 15–200-fold variation in the concentration of the two ingredients believed to have biological activity: ginsenosides and eleutherosides,”​ they noted.


Ernst and his colleagues suggested that the “rigorous implementation”​ of Good Agricultural and Collection Practices (GACP) and Good Manufacturing Practices (GMP) “would undoubtedly reduce the risk of external issues”​ such as contamination and adulteration.

They added that the used of modern pharmaceutical standard analytical methods would ensure herbal products with controllable quality can be manufactured.

The team said that in order to achieve an overall improvement of quality, efforts should be made to deepen methodological research and enhance regulation of herbals.

“Government organisations should assume responsibility to provide active guidance and effective regulation,”​ they concluded.

Source: Complementary Therapies in Medicine
Volume 20, Issues 1–2​, February–April 2012, Pages 100–106, doi: 10.1016/j.ctim.2011.09.004
"Quality of herbal medicines: Challenges and solutions"
Authors: J. Zhang, B. Wider, H. Shang, X. Li, E. Ernst

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Posted by robert rogers,

Ernst and others have been for years cloaking their bias against herbal products using Cochrane Review, meta-analysis that takes a double blind placebo control model and tries to adapt to natural products. It does not work, as the multi compound herbs cannot be measured like a single molecule. the whole thing is so Newtonian and pseudo-science.

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inapropriate regulation and health claim evidence requirements

Posted by Robert Scott,

In her wisdom, Margaret Thatcher once referred to the European Union and being an intellectual is a construct that was not based in pragmatic reality. It should therefore come as no surprise that this dysfunction has been replicated in its second generation Lisbon Treaty with its third generation directives, including THMPD and the health claims directive.

Moira Livingston, in her official report to government from the Working Group on Extending Professional Regulation (WG on EPR), specifically identified what she referred to as "aspirant” groups, which falsely exaggerate alleged risks attached to their profession, as a way of promoting its professional status and through the imposition of Statutory Regulation (SR) by the HPC. The relevance here is that certain self-seeking groups of herbalists have supported the imposition of the regulation of herbal medicine by the MHRA, as a means of pursuing their own professional standing under SR, which, indirectly, is an aspect contained within the provisions of THMPD. This in effect means that they are promoting their personal aspirations at government (public) expense!

There has been a considerable amount of debate over the nature of evidence required for the licensing of herbal medicine products under THMPD and it is particularly alarming that this has also come to involve a "mission creep" to extend these regulations to herbal medicine, in its traditional "non-manufactured product" form.

“WHO defines traditional medicine, of which traditional herbal medicine is part, as follows:

“Traditional medicine is a comprehensive term used to refer both to TM systems such as Traditional Chinese medicine, Indian Ayurveda and Arabic Unani medicine, and to various forms of indigenous medicine. TM therapies include medication therapies — if they involve use of herbal medicines, animal parts and/or minerals — and non-medication therapies — if they are carried out primarily without the use of medication, as in the case of acupuncture, manual therapies and spiritual therapies.

The nature of traditional herbal medicine, as described by the WHO, includes the "spiritual" or "energetic" aspects of the herb as an integral part of their function. There is a particular relevance to this point since the MHRA has declared its intention not to regulate Bach flower remedies in the future. If the MHRA proceed with the regulation of herbal medicine, it would create a situation under which it seeks to regulate one aspect of the herb but not another. Whereas this situation might be just tenable in relation to the manufactured products, it could not be in any way acceptable to herbal medicine in its traditional form. However, even the proposed models for testing herbal medicine products do not withstand scrutiny as a model to ensure standards of safety and efficacy, as claimed.

To explain this point, I refer to the track record of established pharmaceutical products, which have already undergone an allegedly passed this level of scrutiny.

In did 2007 it was reported that more than 8,000 people had died in the previous decade, as a result of taking medicines intended to help them.

Almost 42,000 other patients have been hospitalised after suffering harmful side-effects or serious allergic reactions to prescription drugs and other medication.

The number of deaths from adverse drug reactions - negative responses to medicines resulting from medical error or side-effects -has more than doubled since 1997, rising by 131 per cent.

In the same period, the number of prolonged hospitalisations caused by medicines was up 82 per cent. It costs the NHS as much as £466million a year to treat those who respond badly to medication.

Although alarming, these figures should come as no surprise in the light of a further survey carried out by the BMJ into the efficacy of medicines commonly used within the NHS.

Of around 2500 [commonly used NHS] treatments covered 13% are rated as beneficial, 23% likely to be beneficial, 8% as trade off between benefits and harms, 6% unlikely to be beneficial, 4% likely to be ineffective or harmful, and 46%, the largest proportion, as unknown effectiveness.

These alarming figures clearly demonstrate that the officially accepted modalities of testing are both ineffective and inappropriate, even when used in their appropriate context.

It has also recently come into the public domain that there are marked discrepancies in the officially accepted nature of health claim evidence. Logic dictates that an "health claim" should relate to anything having an impact on the health of the individual, whether the impact be either negative or positive. There has been a move to discount a cannon of empirical knowledge, relating to traditional herbal medicine that has been refined over several millennia and relegate it to the status of unproven rumour. It is. However, precisely this standard of evidence that has been used to vilify the consumption of red meat, under the "health claim" that the consumption of more than one pound per week will have a negative impact on the health of the individual.

There has been no "double blind" testing, no placebo effect testing and no control group used to verify the evidence. This notwithstanding, the findings of this empirical study have been broadcast through the national media as an established "health claim", in an attempt to modify the nation's lifestyle choices. It is a matter of note that traditional herbalists have been offering exactly the same advice, based on their own more extensive cannon of empirical knowledge. This clearly indicates that the official acceptability of the evidence is not dependent upon its empirical nature, but upon source from which it emanates! This in turn is reflected in the official "witch hunt" which has been raised against herbal medicine, on the basis that it provides a viable alternative to the established toxicity of allopathic drugs. To validate this statement, I will refer verbatim to the report from the House of Lords Select Committee on Science and Technology (Section 5.53).

“Their Lordships made this recommendation because, as they explained, “these therapies carry inherent risk, beyond the intrinsic risk that all CAMs (Complementary and Alternative Medicine Systems) pose, which is the omission of conventional medical treatment.”

This statement clearly indicates an agenda to limit the public’s freedom of choice and is an inherently undemocratic attack on herbal medicine in favour of allopathy.

The House of Commons Select Committee Report on the Influence of the Pharmaceutical Industry also officially reported the same unacceptable bias within the MHRA itself!

It states, ‘(t)here are regular interchanges of staff, common policy objectives, agreed processes, shared perspectives and routine contact and consultation. Many of the senior staff of the MHRA have previously worked with the industry …’1 It is therefore doubtful whether the MHRA can be trusted to serve the best interests of herbal medicines, herbalists and their patients.

The consequences of lax oversight is that the industry’s influence has expanded and a number of practices have developed which act against the public interest. The industry affects every level of healthcare provision, from the drugs that are initially discovered and developed through clinical trials, to the promotion of drugs to the prescriber and the patient groups, to the prescription of medicines and the compilation of clinical guidelines. We heard allegations that clinical trials were not adequately designed – that they could be designed to show the new drug in the best light – and sometimes fail to indicate the true effects of a medicine on health outcomes relevant to the patient. We were informed of several high-profile cases of suppression of trial results. We also heard of selective publication strategies and ghost-writing. The suppression of negative clinical trial findings leads to a body of evidence that does not reflect the true risk : benefit profile of the medicine.

Further concerns, expressed in this report, led to the recommendation that the MHRA will be transferred from the auspices of the NHS to those of the Department of Trade and Industry, as it was seen as the de facto promotional wing of the pharmaceutical industry, rather than its watchdog.

The combination of these findings not only clearly indicates that the evidence requirements for MHRA regulation are not only improperly biased, but also lacking in efficacy. In addition to this, it has clearly been established that the MHRA, by nature of its inherent bias, is not fit to exercise any degree of regulation of herbal medicine.

As the main thrust is the cutting of inappropriate red tape within the MHRA, I would also like to bring attention to the professed intention of the MHRA to regulate the manufacture of homeopathic medicine. This can only add unnecessary expense to the manufacture of homeopathic medicine products, the necessity for which cannot be substantiated in the light of the MHRA’s declared intention not to regulate Bach flower remedies! This is a matter of note that homeopathic remedies are biochemically inert, do not contain a single molecule of the material upon which they are based and totally rely upon the subtle energy imprint for their effect. I submit that the subtle energy imprint relates to the "spiritual" aspect referred to in the WHO definition of natural medicine and therefore cannot properly be regulated under a regime designed for allopathic chemicals.

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Edzart Ernst is he still at it?

Posted by Energetic,

Edzart Ernst, I thought he had retired, he is still on a one man mission to hamper alternative and traditional medicine? Ernst loves to court the media, stands behind his title, the press fall easily for his 'this is science' 'this is not science' approach.
The argument of safety is an interesting one, adverse events connected to herbal medicines are statisically extremely rare. When we compare the adverse events and deaths that happen every day from pharmaceutical drugs, which do go through rigourous quality assesments. The FDA, Adverse Events Reporting system, data shows "deaths" totaling 452,780 and "serious outcomes" equaling 2,816,297 occurred during the ten years from 2000 to 2010 as tabulated from the FDA's Adverse Event Reporting System for prescription drugs. IN PLAIN ENGLISH NEARLY HALF A MILLION AMERICANS HAVE DIED FROM PHARMA DRUGS IN THE PAST TEN YEARS.
So the argument is this, yes quality is a good idea, to know something is made well, with the right ingredients, free from contaminants and with consistancy from raw material to finished product is a good idea. However to argue this case on the grounds of safety in relation to herbals is a weak argument. Safety should be in reality about the effect of the substance on the body, this should be monitored far more, just because a drug has been made in a GMP environment and has been shown to be effective, does not mean it should not be monitored for at least a decade after it is on the market.
That is what safety should really mean as this is much more of a problem for pharma drugs than herbals and that is a statisical fact. No matter how much Ernst likes to press release isolated cases and bang on about how much he cannot except that human beings could use the plants that grow on this planet to treat their ills, because it is just not science! I wish the media would accept, his approach to science is entrenched, old fashioned and out of touch, he has demonstrated over the years an irrational dislike of herbal formulations, for reasons that are probably not based in science...

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