Southafricantraditionalplantmedicinaltrade.Challengesinregulatingqualitysafetyandefficacy

Journal of Ethnopharmacology 119 (2008) 705–710

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Journal of Ethnopharmacology
journal homepage: www.elsevier.com/locate/jethpharm

South African traditional medicinal plant trade—Challenges in regulating quality, safety and efficacy
R.A. Street, W.A. Stirk, J. Van Staden ∗
Research Centre for Plant Growth and Development, School of Biological andConservation Sciences, University of KwaZulu-Natal Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa

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Based on the long history of medicinal plant use, users of traditional medicines accept that they are safe for human consumption. However, the absence of regulation of the medicinal plant trade in aspects such as collection,processing and storage provides no such guarantee. Environmental pollution, misidentification and adulteration provides further grounds for concern. The potential adverse effects of South African traditional medicines are not well documented. There are only a few investigations of mutagenic properties and heavy metal contamination. In the absence of regulatory controls, the safety and quality of medicinalplants vary considerably. The current comprehension and future challenges regarding quality, safety and efficacy of South African traditional medicine are discussed. © 2008 Elsevier Ireland Ltd. All rights reserved.

Article history: Received 9 May 2008 Received in revised form 18 June 2008 Accepted 19 June 2008 Available online 27 June 2008 Keywords: Drug development Environmental contaminantsMedicinal plants Pesticide residue Toxic metal accumulation

1. Introduction It is estimated that around 27 million South Africans depend on traditional medicine for their primary health care needs (Mander, 1998). The reliance of such a large portion of the population on traditional medicine can be attributed to a number of factors; relatively good accessibility to the plants, affordability andextensive local knowledge and expertise amongst the local communities (Mander et al., 1996). Secondary metabolites obtained from plants are not benign molecules (Gurib-Fakim, 2006). Plants have evolved such chemical defenses in order to deter, stun, poison or kill threatening species. It would therefore be naive to assume that plant extracts are inevitably safe (Gurib-Fakim, 2006). Nonetheless, acommon misconception is that medicinal plants are “pure and natural” which equates to “harmless”. Inappropriate methods of collection, processing and storage with undesirable contaminants in the products, have all contributed to the negative impact with regards to African natural plant products competing in international markets (Tadmor et al., 2002). The regulation of traditional medicinal plantuse embodies three fundamental aspects: quality, safety and efficacy. Unfortunately, comprehensive safety and efficacy data on traditional medicines

are lacking (Springfield et al., 2005). The shortage of safety and quality controls of South African medicinal plants is further compromised by the fact that there is currently no pharmacopoeia that documents indigenous medicinal plants of South Africa(Fennell et al., 2004a). The objective of this paper is to discuss factors which influence the safety, quality and efficacy of medicinal plants and to highlight current knowledge and future challenges of the South African medicinal plant trade. 2. Factors compromising quality, safety and efficacy of South African medicinal plants Many South African medicinal plants are harvested from the wild. Thisnot only threatens medicinal plant biodiversity and population stability but also leads to speculation with regard to safety as industrial encroachment has led to contamination of water sources and natural habitats. The deposition of processed and unprocessed mining and industrial waste materials (Naicker et al., 2003; Roychoudhury and Starke, 2006) have led to questions of safety for South...