UCL School of Pharmacy


Scientists’ Warning on Climate Change and its Impact on Medicinal Plants

15 November 2019

Scientists from all continents including Professor Michael Heinrich have highlighted the impact climate change has on medicinal plants, their quality and the trade in medicines derived from them.

They highlight the need for actions including conservation and local cultivation of valued plants, sustainability training for harvesters and certification of commercial material, preservation of traditional knowledge, and programs to monitor raw material quality, in addition to, of course, efforts to mitigate climate change (see Applequist et al. Planta medica)

The spice market at Kunming in China. There are samples stored in tubs in a shop.

This warning focuses on the impact climate change already has had and will have on the supply and use of medicinal plants (as well as mushrooms). With the vast majority of the world’s population relying on direct access to traditional and local medicines as their primary resource for medical treatment, and with medicinal plants being an important element of self-care in all countries of the global North, environmental challenges caused by climate change will directly impact on human health.

The spice market at Kunming. A customer is walking down a corridor which is lined with shops selling spices and medicinal products.

The authors highlight that ‘plant populations may be threatened by changing temperature and precipitation regimes, disruption of commensal relationships, and increases in pests and pathogens, combined with anthropogenic habitat fragmentation that impedes migration‘. As highlighted specifically by Michael Heinrich’s group, too, unsustainable harvesting of medicinal species  results in additional pressures pushing many populations to extinction.

Plants respond to increased environmental stresses not only with declines in biomass production but with changes in chemical content, potentially affecting quality or even safety of medicinal products. This calls for a concerted action and research which can be translated into direct measures to mitigate such changes.

The initiative is lead by Dr. Wendy Applequist, and in addition to the core team of authors, has also been endorsed by a group of leading experts representing major societies and journals in the field.

This commentary is based on the Second Warning to Humanity on Climate Change (Ripple et al. 2017;  including 15,364 scientist signatories from 184 countries; BioScience 67: 1026–1028) presented up-to-date evidence for the continuing unsustainable loss of major environmental resources on which humanity depends, and made broad-scale proposals for steps humanity could take to avoid environmental collapse, to call attention to the fact that around the world, human populations’ access to medicinal plants is likely to be threatened by climate change, in addition to the perennial threats of direct anthropogenic habitat loss and overharvesting.


Prof Michael Heinrich - m.heinrich@ucl.ac.uk

Further information:
ScientistsʼWarning on Climate Change and Medicinal Plants - https://www.thieme-connect.com/products/ejournals/pdf/10.1055/a-1041-340...