Heavy Metals Alter the Potency of Medicinal Plants

Heavy metals, accumulated naturally in soil, surface water or through industrial and mining processes, pose a potential threat to various terrestrial and aquatic organisms (Greeger 1999; Larison et al. 2000; Dwivedi and Dey 2002; Hsu et al. 2006; Dhir et al. 2008). Exposure to high metal concentrations impinges on the growth and development of plants (Rout and Das 2003; Shanker et al. 2005; Dhir et al. 2009). Such growth effects result from alterations in physiological events such as photosynthesis, respiration, changes in lipid composition, enzyme activity, and distribution of macro and micronutrients at the cellular level (Sheoran et al. 1990; Van Assche and Clijsters 1990; Rout and Das 2003; Shanker et al. 2005). Research also suggests that abiotic factors such as heavy metals may alter the production of bioactive compounds by changing aspects of secondary metabolism (Verpoorte et al. 2002). © 2010 Springer Science+Business Media, LLC.