title: A review on the elemental contents of Pakistani medicinal plants: Implications for folk medicines.
abstract: BACKGROUND
  Substantially, plants produce chemicals such as primary and secondary metabolites, which have significant applications in modern therapy. Indigenous people mostly rely on traditional medicines derived from medicinal plants. These plants have the capacity to absorb a variety of toxic elements. The ingestion of such plants for medicinal purpose can have imperative side effects. Hence, with regard to the toxicological consideration of medicinal plants, an effort has been made to review the elemental contents of ethno medicinally important plants of Pakistan and to highlight the existing gaps in knowledge of the safety and efficacy of traditional herbal medications.
  
  
  METHODS
  Literature related to the elemental contents of ethno medicinal plants was acquired by utilizing electronic databases. We reviewed only macro-elemental and trace elemental contents of 69 medicinal plant taxa, which are traditionally used in Pakistan for the treatment of sundry ailments, including anemia, jaundice, cancer, piles, diarrhea, dysentery, headache, diabetes, asthma, blood purification, sedative and ulcer.
  
  
  RESULTS
  A majority of plants showed elemental contents above the permissible levels as recommended by the World health organization (WHO). As an example, the concentrations of Cadmium (Cd) and Lead (Pb) were reportedly found higher than the WHO permissible levels in 43 and 42 medicinal plants, respectively. More specifically, the concentrations of Pb (54ppm: Silybum marianum) and Cd (5.25ppm: Artemisia herba-alba) were found highest in the Asteraceae family.
  
  
  CONCLUSIONS
  The reported medicinal plants contain a higher amount of trace and toxic elements. Intake of these plants as traditional medicines may trigger the accumulation of trace and toxic elements in human bodies, which can cause different types of diseases. Thus, a clear understanding about the nature of toxic substances and factors affecting their concentrations in traditional medicines are essential prerequisites for efficacious herbal therapeutics with lesser or no side effects.
authors.affiliation: Department of Botany, Kohat University of Science and Technology, Kohat 26000, Pakistan.
authors.forename: Muhammad Abdul
authors.initials: MA
authors.lastname: Aziz
authors.affiliation: Department of Botany, Kohat University of Science and Technology, Kohat 26000, Pakistan. Electronic address: ghurzang@hotmail.com.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Adnan
authors.affiliation: Department of Environmental Sciences, Fatima Jinnah Women University, The Mall Rawalpindi 46000, Pakistan.
authors.forename: Shaheen
authors.initials: S
authors.lastname: Begum
authors.affiliation: Department of Botany, Kohat University of Science and Technology, Kohat 26000, Pakistan.
authors.forename: Azizullah
authors.initials: A
authors.lastname: Azizullah
authors.affiliation: Department of Chemistry, Kohat University of Science and Technology, Kohat 26000, Pakistan.
authors.forename: Ruqia
authors.initials: R
authors.lastname: Nazir
authors.affiliation: Department of Environmental Sciences, Fatima Jinnah Women University, The Mall Rawalpindi 46000, Pakistan.
authors.forename: Shazia
authors.initials: S
authors.lastname: Iram
mesh_terms: D000818:Animals; D019448:Ethnobotany; D020834:Ethnopharmacology; D006801:Humans; D008519:Medicine, Traditional; D010154:Pakistan; D008517:Phytotherapy; D010936:Plant Extracts / Q000009:adverse effects* / Q000302:isolation & purification / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry* / Q000145:classification; D018570:Risk Assessment; D012621:Seasons; D013997:Time Factors; D018675:Toxicity Tests; D014131:Trace Elements / Q000009:adverse effects* / Q000302:isolation & purification / Q000494:pharmacology
chemical_list: D010936:Plant Extracts; D014131:Trace Elements
keywords: Ethno medicinal plants; Ethnobotany; Macro-elements; Toxic effects; Trace elements