Sustainability of herbal medicines and supply chains are very complex topics and issues vary between plants and cultures. This article sheds light on some of the issues with plants from Traditional Chinese Medicine.
There is no doubt that the expansion of Chinese herbal medicine around the world is having a negative impact on the environment and threatens an increasing number of wild plant species. Do we want to be a part of this problem or part of the solution?
It is a complex question as we may feel we have little control over the root causes, but it may be helpful to ask who is actually responsible for the solution.
Let’s start with the Chinese government. Should they not protect the wild plants? In fact, there is more land area given over to protected nature reserves in China (14.8%) (1) compared to 0.7% in the UK (2, 9). In such unpolluted areas such as in the Qinling Mountains, emphasis is given over to forestry and herb cultivation. Land in the lowlands is facing increasing pressure from building use, pushing herb farmers back into the hills where many of them come from. This is a good development. They are valuable ‘di dao’ areas. Similar to the terroir appellation for wine, di dao areas are renowned for having specific ecological characteristics that produce herbs with superior qualities and benefits. These regions are recognised as optimum regions to source certain specific species of herbs.
It is estimated that around 80% of the medicinal herb species by species number (not volume) used in Chinese herbal medicine are wild sourced (3). The concerning matter is that the output of wild collecting is reducing each year. In 2007 the Chinese Academy of Science with the State Forestry Administration produced their blueprint for the conservation of wild plants including medicinal plants. A positive outcome is that it has many important and far reaching policies including the protection of di dao regions.
One example that we may not even have considered is the extraction of wild Glycyrrhiza uralensis (gan cao) from the northern regions of China.
In the wild, gan cao is one of the important ground cover plants stabilising the shifting sands at the fringes of the Gobi desert. Removal of the ground cover is largely responsible for the increasing dust storms experienced in Beijing. The situation is being monitored using satellite imagery and steps are being taken to restore the habitat.
For us herbalists we think of gan cao as a common and ecologically sustainable herb, but only if it is taken in a sustainable manner from the wild, which it is not. The most rigorous standards for sustainable collection are run by The FairWild Foundation. Liquorice can be sustainably harvested under FairWild standards (4) and there are projects in Khazakhstan, Georgia, Uzbekistan and Spain currently in place. Anecdotal conversations with suppliers indicate that cultivated liquorice contains lower levels of the sweet glycyrrhizic acid compared to wild harvested.
Desert regions are also the natural habitat for Ephedra sinica (ma huang). In 2013, Ephedra sinica was declared ‘near threatened and rapidly declining’ according to the IUCN Red list of threatened species (5). It is the first Chinese herb to be protected by quotas. Issuing licences for collecting is an effective control which may be the way ahead for other herbs in this delicate ecosystem. You can read more about the sustainability of liquorice in our article “The sustainability of liquorice”.
Another important part of the 2007 Conservation Policy is to develop key labs for the cultivation of medicinal plants which are endangered. This is not a new policy as they have been trying to cultivate over 400 species of Chinese herbs for the past 50 years with considerable success. Since the 1955 to 2015 the land areas given over to medicinal herb cultivation has increased from 400.000 square hectares to 9.330.000 square hectares. Although this is a vital part of the programme towards sustainability, the use of toxic pesticides and increase in heavy metals in the soils has rendered some products unsuitable for use (6).
A more ecologically sensitive method is being explored for some herbs including Glycyrrhiza (7)and Fritillaria by establishing a method called ‘natural fostering’ by planting the herb crops within their natural habitat. Although the yields are not high enough to replace commercial cultivation, the quality of the herb most resembles that of the wild harvested.
Some of these herbs are not easy to cultivate. A national award was given for the commercial cultivation of Gastrodia elata (tian ma).
It is now possible to not only sustainably produce this rare orchid but the smaller plants are then introduced into the wild to increase wild stock
You can identify commercially grown and wild harvested tian ma in the markets in whole root form at least. However, for other species it is not so easy and currently most suppliers source their herbs from large markets where the source is unknown.
A key herb chosen in the 2007 report concerns Fritillaria species. In particular Fritillaria cirrhosa (chuan bei mu) Over 1 million yuan was allocated for the one species alone to improve cultivation. As an important ingredient of traditional cough medicine, this plant is estimated to fuel a 400 million dollar industry. Cultivation is now proceeding in Sichuan but, although protected in the wild, the livelihood of poor people is pushing the collection of more and more rare Fritillaria species through indiscriminate harvesting methods.
You can see that the bulbs on the left are closed compared to the right where they have opened. The opening of the bulb indicates that it has flowered and hence less damaging for the continuation of the species. Wild collection training and increased incentive to sustainably collect will help but these are often illegal harvesters in a poverty area.
The other major development is the establishment of GAP centres in each region of China.
The standard and sourcing provenance of the herbs can be greatly improved with these GAP centres compared to individual small growing and harvesting. Whilst this is a good plan overall, it does have implications which are less helpful.
Many small farmers rely on the increase in price afforded by processing.
By having to sell their raw product to the GAP centre to be processed, their income is greatly reduced. Without a stable income many young farmers are simply leaving the industry which is hard and unsustainable.
Herb prices are also very volatile for the farmer- fluctuating according to the amount of herb on the market. This is why there is provision in the conservation plan to stabilise herb prices. It may not be enough to stop the exodus of young farmers.
What can we do as consumers at the end of these long supply chains? Firstly, we need to be vigilant when choosing our herbs and ask more questions. We can make choices. For example, we can try to avoid using herbs which are endangered.
We can use zhe bei mu (Fritillaria thunbergii) instead of chuan bei mu. Zhe bei mu is cultivated in Zhejiang province. It is doubtfully native in China.
Zhe bei mu is easily to differentiate macroscopically from chuan bei mu due to its larger size and open structure.
It is true that zhe bei mu is more for excess heat and early nodes than the gentler chuan bei mu. However, we can adjust the dosages and formulation accordingly. Our formulas are designed to be flexible.
Another example is that of sha shen. There are 2 official species for this herb. Nan sha shen from the south is sourced from Adenophora tetraphylla which is not endangered in the wild. In the north the source is Glehnia littoralis which is now on the critical endangered list in the wild (8).
In sliced form they are easy to tell apart as the nan sha shen shown on the left is much looser than the harder bei sha shen, which also shows a distinct cambium ring. We should revert to only using nan sha shen unless we have assurance that the Glehnia has been cultivated.
We can also become aware of other herbs which are being pushed toward extinction in the wild. We should ask of our supplier if these herbs are wild collected or cultivated. They may not claim to know the answer, but they should make the extra effort to find out. At the same time they should be better at labelling the source species as it is often left vague where several substitutions exist.
Does the responsibility rest with our suppliers or ourselves as consumers?
The RCHM Approved Suppliers Scheme does offer at least some dialogue to move more into sourcing control. All the suppliers in this scheme are aware of the problem and attempting to check their sources. Affiliated with the BHMA’s Herbal Practitioner Supplier Scheme, whilst it lacks specific reference to sustainability, it does keep dialogue between practitioners and suppliers open.
Once a herb has reached the CITES lists for endangered species it is already serious. In order to obtain CITES certification for a small batch of herbs coming to the UK, the cost and time taken means that the herb is simply dropped. One issue faced by suppliers trying to meet new expectations is that the cost of the herb will usually need to be increased. From their experience the customer is unwilling to pay for this increased selectivity. Put simply, herbalists will normally still buy on the basis of cost in the same way as we want cheap food at the supermarket despite the implications.
One interesting area is that of finding suitable substitutes for endangered herbs. We have had to do this with animal products, so it can and needs to be done. As with animal products there is often not one simple replacement. We need to know exactly what the herb is doing in the formula and its importance. It may require simply dropping it and increasing other herbs or finding a few herbs to do the same job. It is a creative process which would require an article in itself.
Dendrobium orchid species used as sources for the Chinese herb shi hu, are another plant threatened in the wild.
Although it is also cultivated in small amounts it is impossible to tell in the markets.
Perhaps we could consider herbs closer to home. The western pharmacology and use of our native Althaea officinalis (marshmallow) indicate it is a possible substitute for the orchid Dendrobium nobile (shi hu).
The switch to using more locally based herbs in TCM is another topic in itself and beyond the scope of this discussion. As is the increasingly common but difficult question of cultivating authenticated Chinese herbs in the UK
So, to answer the initial question posed in the title, we are all responsible for the situation of unsustainable use of herbs and we all need to find our own solution. We may have to restrict or substitute our materia medica as we have already done by eliminating animal products. Or we may have to be prepared to pay more for authenticated sustainable herbs which will cost more to produce and monitor.
Either way, we cannot avoid it. It is a challenge that is inherent in the term ‘unsustainable’.
References
- Zhijun Ma et al Ministry of Education-key labs for biodiversity science: Conserv Biol 2019 33(5) 1066-1075
- UKBI – C1. Protected areas | JNCC – Adviser to Government on Nature Conservation. Published December 14, 2022. https://jncc.gov.uk/our-work/ukbi-c1-protected-areas/
- ShilinC, PeigenX Introduction to the sustainable utilisation of Chinese Herbal Medicine. China Medical Technology Publication 2006
- FairWild Foundation. Liquorice — FairWild Foundation. FairWild Foundation. Published online August 1, 2023. https://www.fairwild.org/ingredients/liquorice
- The IUCN red list of threatened species. IUCN Red List of Threatened Species. https://www.iucnredlist.org/
- Xu R, ChenJ, ChenS Medicinal plant resources achieve rational development China Pharmaceutical 2009 18
- Wei SL, Wang WQ, Wang H. [Study on licorice resources and their sustainable utilization in center and western area of China]. PubMed. Published March 1, 2003. https://pubmed.ncbi.nlm.nih.gov/15015299/
- Leon C, Yu-Lin L. Chinese Medicinal Plants Herbal Drugs and Substitutes: An Identification Guide: An Identification Guide. Vol 1. Kew Publishing; 2017.
- Morris S. How much of England is protected for nature? Government may fail in delivering 2030 nature target. Evening Standard. https://www.standard.co.uk/news/environment/england-land-sea-protected-nature-uk-government-target-b1033834.html. Published July 27, 2023.