Abstract
The increasing prevalence of environmental pollution, especially soil contamination with heavy metals has led to their uptake in the human food chains through plant parts. Accumulation and magnification of heavy metals in human tissues through consumption of herbal remedies can cause hazardous impacts on health. Therefore, chemical profiling of nine heavy metals (Mn, Cr, Pb, Fe, Cd, Co, Zn, Ni and Hg) was undertaken in stem and leaf samples of ten medicinal plants (Acacia nilotica, Bacopa monnieri, Commiphora wightii, Ficus religiosa, Glycyrrhiza glabra, Hemidesmus indicus, Salvadora oleoides, Terminalia bellirica, Terminalia chebula and Withania somnifera) collected from environmentally diverse regions of Haryana and Rajasthan states in North-Western India. Concentration of all heavy metals, except Cr, was within permissible limits in the tested stem and leaf samples. Leaf samples had consistently more Cr compared to respective stem samples with highest concentration in leaf samples of Bacopa monnieri (13.19 ± 0.0480 ppm) and stem samples of Withania somnifera (4.93 ± 0.0185 ppm) both collected from Bahadurgarh (heavy industrial area), Haryana. This amount was beyond the permissible limit of 2.0 ppm defined by WHO for raw herbal material. Other two most perilous metals Pb (2.64 ± 0.0260) and Cd (0.04 ± 0.0274) were also recorded in Bahadurgarh region, although below permissible limits. Concentration of Hg remained below detectable levels in all the leaf and stem samples tested. These results suggested that cultivation of medicinal plants and other dietary herbs should be curtailed near environmentally polluted especially industrial areas for avoidance of health hazards.
Highlights
Herbal medicines being natural are preferred over synthetic remedies by a major section of the world
Results of analysis of nine heavy metals (Mn, Cr, Pb, Fe, Cd, Co, Zn, Hg and Ni) done in stem and leaf samples of ten medicinal plant species are summarized in Tables 4 and 5 respectively
Mn concentration was more in the stem samples, ranging from 1.65 fold in A. nilotica to 7.03 fold in W. somnifera, compared to respective leaf samples except C. wightii wherein leaf samples accumulated more Mn (Figure 3)
Summary
Herbal medicines being natural are preferred over synthetic remedies by a major section of the world. Accumulation of toxic industrial effluents in the soil is continuously increasing due to fast urbanization and extensive pollution of the environment Among these toxic substances, presence of heavy metals (HMs; atomic weights 63.5–200.6 g mol−1 and a specific gravity greater than 5 g cm−3) which are ubiquitous in nature, cause serious harmful effects on living organisms (Nies, 1999; Lee and Lee, 2002). Accumulation and concentration of HMs in plants is influenced by various attributes including atmospheric depositions (depend on traffic densities, metal mining and smelting operations), concentration and bioavailability of HMs in soil (through addition of pesticides and sewage sludge), the nature of soil where herbs are grown (pH and organic matter concentration), individual plant performance (degree of maturity of the plant, time of harvest) and manufacturing conditions of herbal drugs (grinding weights, lead-releasing containers and manufacturing utensils) etc (Nwoko and Mgbeahuruike, 2011). Metal mediated hazardous impacts can be direct or indirect via binding of metals with pharmacologically active substances or by manipulating the pharmacokinetics (Weber and Konieczyński, 2003)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
