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1 Microchemical Journal 95 (2010) Contents lists available at ScienceDirect Microchemical Journal journal homepage: Determination of essential and non-essential elements in some medicinal plants by polarised X ray fluorescence spectrometer (EDPXRF) Donatella Desideri, Maria Assunta Meli, Carla Roselli Institute of General Chemistry, Urbino University, Carlo Bo, P.zza Rinascimento 6, Urbino, Italy article info abstract Article history: Received 16 October 2009 Received in revised form 16 November 2009 Accepted 16 November 2009 Available online 28 November 2009 Keywords: EDPXRF Essential elements Toxic elements Medicinal plants Polarised X ray fluorescence spectrometer (EDPXRF) is employed for the determination of essential and nonessential elements in the parts (leaves, fruits, seeds, roots, flowers, barks, berries, and thallus) of thirty-five medicinal plants used in Italy generally as remedies. The quality of data was assured by calibrating the instrument with certified reference materials. The elements are found to be present in different plants in various proportions depending on soil composition and the climate in which the plant grows Elsevier B.V. All rights reserved. 1. Introduction In recent times, focus on plant research has increased all over the world and a large body of evidence has been collected to show the immense potential of medicinal plants used in various traditional systems. The therapeutic effect of these plants for the treatment of various diseases is based on the chemical constituents present in them [1,2]. Although the efficacy of herbs for curative purposes is often accounted for in terms of its organic constituents (essential oil, vitamins, glycosides, etc.) it has been established that there exists a relationship between the chelating of metals and some chemotherapeutic agents [3]. Trace elements play a very important role in the formation of the active chemical constituents present in medicinal plants and are there responsible for their medicinal as well as toxic proprieties; in fact, it has been pointed out that not all natural therapies or products related to complementary or alternative medicine are free from adverse effects [4]. The role of inorganic elements in animal and plant metabolism has long been established, but the effect and influences of these elements on administration of medicinal plant have received relatively little attention. The administration of medicinal plant, traditionally has been largely indiscriminate without due regard to possible side effects. Diet has long been considered as the major source of human exposure to trace elements and consequently the levels in basic foodstuff, but medicinal uptakes Corresponding author. Tel.: ; fax: address: donatella.desideri@uniurb.it (D. Desideri). are of greater interest from the toxicological and nutritional points of view [5]. Thus, a quantitative estimation of various essential or toxic element concentrations is necessary for determining the effectiveness of the medicinal plants in treating various diseases and also to understand their pharmacological action. Moreover, such an assessment would be helpful in regulating their use as certain elements are toxic at elevated levels. It is interesting to note that comparison of the elemental contents of these medicinal herbs with that of usual plants (non-medicinal) as rice, tomato, field bean and edible bitter herb shows that medicinal plants are more rich in elemental content than usual plants with a few exceptions [6]. This study aimed to evaluate the elemental composition of some medicinal plants used in Italy by polarised X ray fluorescence spectrometer (EDPXRF). EDPXRF is a simultaneous, reliable, sensitive, quantitative multielemental and non-destructive technique, suitable for routine analysis due to minimal sample preparation. This technique has been used successfully by various authors for the characterization of different complex matrices. The elements taken into account are 23 subdivided into essential (macro and micro) and non-essential or toxic. An element is considered essential if the plant fails to grow normally and to complete its life cycle, if grown in a medium adequately removed from the element, whereas in the presence of the suitable chosen concentration of the element it grows and reproduces normally [7]. Among the essential elements estimated in the present work we found the micro and trace elements (Mn, Fe, Co, Cu, Zn, Ni, Cr, Cl, Br, and I) and macro elements (K, Mg, Ca, P, and S); along the nonessential elements and the toxic elements Al, Rb, Sr, As, Cd, Sn, Pb and Hg are taken into account X/$ see front matter 2009 Elsevier B.V. All rights reserved. doi: /j.microc

2 D. Desideri et al. / Microchemical Journal 95 (2010) Table 1 Details of the medicinal plants under study. Botanical name (Common name) Part used Origin crop year Cultivation Malva sylvestris L. (Mauve) Leaves Italy 2007 Organic farming Salvia officinais L (Sage) Leaves Italy 2007 Organic farming Mentha piperita L. (Peppermint) Leaves Italy 2007 Organic farming Melissa officinalis L. (Balm-mint) Leaves Italy 2007 Organic farming Fraxinus excelsior L. (Ash) Leaves Hungary 2006 Spontaneous Thymus serpyllum L. (Thyme) Leaves Albania 2007 Spontaneous Calendula offcinalis L. (Calendula) Flowers Slovakia 2006 Cultivated Matricaria recutita Rausch (Chamomile) Flowers Italy 2006 Organic farming Lavanda angustifolia Miller (Lavander) Flowers Italy 2007 Cultivated Helichrysus stoecas (Elicriso) Flowers Hungary 2006 Cultivated Humulus Lupulus (Hops) Flowers Far East 2007 Cultivated Plantago arenaria (Nero psyllium) Seeds Italy 2007 Cultivated Foeniculum vulgare Miller (Fennel) Seeds Turkey 2007 Cultivated Linum usitatissimum L. (Flax) Seeds Italy 2007 Organic farming Elettaria cardamomum (Cardamom) Seeds Cultivated Cynodon dactylon Pers. (Dog's-tooth) Roots China 2007 Spontaneous Taraxacum officinale (Dandelion) Roots Poland 2007 Cultivated Arctium lappa L. (Burdock) Roots Italy2007 Organic farming Glycyrrhiza glabra L. (Liquorice) Roots Italy 2007 Cultivated Rosa canina L. (Rosehip) Fruits Chile 2007 Spontaneous Illicium verum (Star anise) Fruits Far East 2007 Cultivated Capsicum FR (Pepper) Fruits India 2007 Cultivated Vitex agnus castus krus (Lilac chastetree) Fruits Albania 2007 Cultivated Salix alba (White willow) Barks Spontaneous Frangula alnus Miller (Alder buckthorn) Barks Poland 2006 Cultivated Rhamnus purshiana (Bearberry) Barks USA 2007 Cultivated Ulmuis campestris L. (Elm) Barks Italy 2007 Spontaneous Cinnamomum Zeylanicus (Cinnamon) Barks Srilanka 2007 Cultivated Vaccinium myrtillus L. (Blueberry) Berries Hungary 2007 Cultivated Cupressus serpenvirens (Cypres) berries Italy 2007 Cultivated Juniperus communis (Juniper) Berries Italy2007 Cultivated Abies pectinata (Spruce) Berries. Italy 2007 Spontaneous Spirulina maxima (Alga Spirulina) Thallus Laminaria cloustonule (Alga Laminaria) Thallus France 2007 Spontaneous Fucus vesiculosus L. (Bladder wrack) Thallus France 2006 Spontaneous Table 2 Concentration (mg kg 1 dry) of essential macroelements in the studied medicinal plant. Botanical name Part used K Mg Ca P S Malva sylvestris L Salvia officinais L Mentha piperita L. Leaves Melissa officinalis L Fraxinus excelsior L Thymus serpyllum L Calendula offcinalis L Matricaria recutita Rausch Flowers Humulus lupulus Lavanda angustifolia Miller Helichrysus stoecas b Plantago arenaria Wald. et Kit Foeniculum vulgare Miller Seeds Linum usitatissimum L Elettaria cardamomum Cynodon dactylon Pers b Taraxacum officinale Weber Roots b Arctium lappa L Glycyrrhiza glabra L Rosa canina L Capsicum FR Fruits b Vitex agnus castus krus Illicium verum Ulmuis campestris L b Cinnamomum Zeylanicus Salix Alba Barks b Rhamnus purshiana Frangula alnus Miller Juniperus communis Abies pectinata Berries b Vaccinium myrtillus L b Cupressus serpenvirens Laminaria cloustonule Fucus vesiculosus L. Thallus b Spirulina maxima

3 176 D. Desideri et al. / Microchemical Journal 95 (2010) Essential metals can also produce toxic effects when the metal intake is in high concentrations [8]; whereas non-essential metals are toxic even in a very low concentration for human health and the environment [9]. Potassium and magnesium are essential electrolytes for maintaining normal fluid balance in cells and a delicate balance of these two elements is reported to prevent an increase in blood pressure and to maintain normal cardiac rhythm. Calcium is known to be involved in muscle contraction and relaxation, blood clotting, proper nerve function and body immune defenses. The biological roles of K, Mg and Ca are essential for disease prevention and control. Chloride is the chief anion of extracellular fluid which is responsible for muscular irritability. P is essential for growth and renewal of tissues. Phosphorus compounds carry, store and release energy and they assist many enzymes and vitamins in extracting the energy from nutrients. Fe, Cu, Mn and Zn are essential elements in enzyme metabolism. They have immunomodulatory functions and thus influence the susceptibility to the course and the outcome of a variety of viral infections [2]. The importance of iron in maintaining good health and well being has long been recognized by nutritionists. Manganese plays a vital role in the control of diabetes, while Zn has an anti-diarrhoea activity and regulates fertility. Table 3 Concentration (mg kg 1 dry) of essential elements (micro and trace) in the studied medicinal plants. Botanical name Part used Cr Mn Fe Co Ni Cu Zn Malva sylvestris L Salvia officinais L b Mentha piperita L. Leaves Melissa officinalis L b Fraxinus excelsior L. b b Thymus serpyllum L Calendula offcinalis L b Matricaria recutita Flowers Rausch Humulus Lupulus b b Lavanda angustifolia b b Miller Helichrysus stoecas b b Plantago arenaria b b Wald. et Kit. Foeniculum vulgare Seeds b Miller Linum usitatissimum L. b b Elettaria cardamomum b Cynodon dactylon Pers. 6.6 b b Taraxacum officinale Roots b b Weber Arctium lappa L. b b Glycyrrhiza glabra L. b2 b b Rosa canina L. b b Capsicum FR Fruits b b Vitex agnus castus krus b Illicium verum b b Ulmuis campestris L b b1 b Cinnamomum b Zeylanicus Salix Alba Barks b b Rhamnus purshiana b b Frangula alnus Miller b b Juniperus communis b b Abies pectinata Berries b b Vaccinium myrtillus L. b b Cupressus serpenvirens b2 b b1 b Laminaria cloustonule b Fucus vesiculosus L. Thallus Spirulina maxima b Co in the form of Vitamin B-12 is in its physiologically active form. Although there are no reported physiological effects of Sr and Rb at low concentrations, their accumulation in the body system could be detrimental to health. Cd, Pb, Hg and Al have no known physiological function yet reported. They are reported to be toxic and should be considered as a high risk factor to public health in general [7]. Cd has an adverse effect on brain metabolism and has other severe effects such as prostate cancer, kidney, liver, lungs and bone damage. Children are particularly at risk from Pb consumption, both before and after birth [10]. 2. Experimental 2.1. Samples and sampling 35 medicinal plants coming from different countries were purchased in dried form of roots, leaves, barks, seeds, flowers, fruits, berries and thallus from local herbalists. Table 1 lists, for the medicinal plants selected for the present study, the common name, the scientific or botanical name, the particular part analysed, the kind of cultivation (spontaneous, cultivated or organic farming), the country of origin and the crop year Analytical methods Samples were dried in an oven at 80 C until constant mass was obtained. The dry mass value was used to determine the concentration. Then the samples were measured by polarised X ray fluorescence spectrometer. Each sample was prepared by finally pulverising the dried materials in a vibrating mill (equipped with a zirconia made grinding Table 4 Concentration (mg kg 1 dry) of essential elements (halogens) determined in the medicinal plant selected in this study. Botanical name Part used Cl Br I Malva sylvestris L Salvia officinais L Mentha piperita L. Leaves Melissa officinalis L Fraxinus excelsior L Thymus serpyllum L Calendula offcinalis L Matricaria recutita Rausch Flowers Humulus Lupulus Lavanda angustifolia Miller Helichrysus stoecas Plantago arenaria Wald. et Kit Foeniculum vulgare Miller Seeds Linum usitatissimum L Elettaria cardamomum Cynodon dactylon Pers Taraxacum officinale Weber Roots Arctium lappa L Glycyrrhiza glabra L Rosa canina L b1 6.3 Capsicum FR Fruits Vitex agnus castus krus 38.6 b1 5.7 Illicium verum 32.4 b1 5.5 Ulmuis campestris L b20 b1 5.7 Cinnamomum Zeylanicus Salix Alba Barks 44.4 b1 6.2 Rhamnus purshiana b Frangula alnus Miller b20 b1 6.9 Juniperus communis b1 7.0 Abies pectinata Berries b1 6.1 Vaccinium myrtillus L. b20 b1 7.3 Cupressus serpenvirens Laminaria cloustonule Fucus vesiculosus L. Thallus Spirulina maxima b1 7.0

4 D. Desideri et al. / Microchemical Journal 95 (2010) Table 5 Concentration (mg kg 1 dry) of non-essential or toxic elements determined in the medicinal plant selected in this study. Botanical name Part used Al As Rb Sr Cd Sn Hg Pb Malva sylvestris L b b Salvia officinais L b b b Mentha piperita L. Leaves b b b Melissa officinalis L b b0.5 b0.1 b Fraxinus excelsior L. b100 b b Thymus serpyllum L b b0.5 b0.1 b Calendula offcinalis L. b100 b b0.5 b0.1 b Matricaria recutita Rausch Flowers b100 b b0.5 b0.1 b Humulus Lupulus b b b Lavanda angustifolia Miller b b b Helichrysus stoecas b100 b b0.1 b Plantago arenaria Wald. et Kit. b100 b b b0.1 b0.1 Foeniculum vulgare Miller Seeds b100 b b0.5 b0.1 b0.1 b0.1 Linum usitatissimum L. b100 b b b0.1 b0.1 Elettaria cardamomum b100 b b0.5 b0.1 b Cynodon dactylon Pers. b100 b b b Taraxacum officinale Weber Roots b b b Arctium lappa L b b Glycyrrhiza glabra L. b100 b b b Rosa canina L. b100 b b b Capsicum FR Fruits b100 b b b Vitex agnus castus krus b b0.5 b0.1 b Illicium verum b b b Ulmuis campestris L b100 b b b Cinnamomum Zeylanicus b b b Salix Alba Barks b100 b b Rhamnus purshiana b100 b b b Frangula alnus Miller b100 b b b Juniperus communis b100 b b b Abies pectinata Berries b100 b b b Vaccinium myrtillus L. b100 b b b Cupressus serpenvirens b100 b b b Laminaria cloustonule b b Fucus vesiculosus L. Thallus b Spirulina maxima b100 b b b system) and mixing it with Wachs-C Mikropulver, a paraffin wax that helps to reduce the sample to tablet though pressure. The determinations were done with a Spectro-X-LAB2000 (SN DK ), energy dispersive, polarised X ray fluorescence spectrometer (EDPXRF). The quality of data was assured by calibrating the instrument with the following certified reference materials (CRM): MURST-ISS-A1 Marine sediment, GBW07310 Stream sediment, GBW07310 Stream sediment, GBW08303 Farmland Soil, LGC6138 Soil, SRM Sludge, STD Fly ash, BCR CRM 144R Sludge, CCRM LKSD1 Lake sediment, CCRM PACS-2 Marine sediment, NIST SRM 2709 Agricultural soil, NIST SRM 2711 Montana soil, and NIST SRM 1633b Fly ash. The analytical precision, measured as relative standard deviation, for Pb, Cd, As, Zn, Cu, Ni, Mn and Cr, was routinely between 10 and 6%, but about 10% for Cr. The averaged analytical standard errors observed with the reported certified materials were below 10% for Cr, As and Cd, and below 7% for Mn, Ni, Cu, Zn and Pb. 3. Results and discussion The medicinal plants were subdivided in 8 groups on the basis of the analysed part and used in the traditional use (roots, leaves, barks, seeds, flowers, fruits, berries and thallus). An examination of the data from Tables 2 5 shows that different medicinal plants contain the elements K, Rb, Mg, Ca, Sr, Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Sn, Hg, Pb, P, As, S, Cl, Br, and I, in various proportions. Along macro elements, K ranges from to mg kg 1 dry (thallus of Laminaria cloustonule); Mg from b500.0 to mg kg 1 dry (leaves of Malva sylvestris); Ca from to mg kg 1 dry (barks of Salix alba); P ranges from to mg kg 1 dry (thallus of Spirulina maxima). Cl ranges from b20.0 to (thallus of L. cloustonule). Taking into account the minor and trace elements, Fe, Mn, Cu and Zn range from 29.4 to mg kg 1 dry (leaves of Thymus serpyllum), from b6.0 to mg kg 1 dry (barks of Frangula anlus), from 2.3 to 20.3 mg kg 1 dry (roots of Arctium lappa) andfrom5.4to mg kg 1 dry (barks of S. alba) respectively. Co ranges from b1 to 6.5 mg kg 1 dry (leaves of Tymus serpyllum). Along non-essential Table 6 Comparison, for every element, between the arithmetical mean of all values and the maximum concentration (mg kg 1 ). Element Mean value Max value Plant K Laminaria cloustonule Mg Malva sylvestris Ca Salix alba P Spirulina maxima S Laminaria cloustonule Cr Thymus serpyllum Mn Frangula anlus Fe Thymus serpyllum Co Thymus serpyllum Ni Thymus serpyllum Cu Arctium lappa Zn Salix alba Cl Laminaria cloustonule Br Laminaria cloustonule I Laminaria cloustonule Al Mentha piperita As Laminaria cloustonule Rb Ilicium verum Sr Laminaria cloustonule Cd Laminaria cloustonule Sn Laminaria cloustonule Pb Laminaria cloustonule Hg Fucus vesiculosus

5 178 D. Desideri et al. / Microchemical Journal 95 (2010) Table 7 Arithmetical mean, standard deviation, minimum and maximum values (mg kg 1 dry) of essential elements (macro) determined in the medicinal plants selected in this study. Part used K Mg Ca P S Leaves Mean±σ ± ± ± ± ± Minimum Maximum Flowers Mean±σ ± ± ± ± ±578.9 Minimum b Maximum Seeds Mean±σ ± ± ± ± ± Minimum Maximum Roots Mean±σ ± ± ± ± ±336.6 Minimum b Maximum Fruits Mean±σ ± ± ± ± ± Minimum b Maximum Barks Mean±σ ± ± ± ± ± Minimum b Maximum Berries Mean±σ ± ± ± ± ±139.0 Minimum b Maximum Thallus Mean±σ ± ± ± ± ± Minimum b Maximum elements, Rb and Sr range from 1.6 to 83.3 mg kg 1 dry (fruits of Ilicium verum) and from 2.8 to mg kg 1 dry (thallus of L. cloustonule) respectively. The toxic elements as Cd, Pb and Al range from b0.5 to 5.5 mg kg 1 dry (thallus of L. cloustonule), from b0.1 to 4.9 mg kg 1 dry (thallus of L. cloustonule)andfromb100 to mg kg 1 dry (leaves of Mentha piperita). Hg is always b0.1 mg kg 1 dry except for Fucus vesiculosus L. (0.8 mg kg 1 dry). As is always b1.0 mg kg 1 dry except for L. cloustonule (74.0 mg kg 1 dry) andf. vesiculosus L. (47.5 mg kg 1 dry). Table 6 shows, for every element, the comparison between the arithmetical mean of all values and the maximum concentration. It is possible to note that the thallus of the algae is very rich of elements: for essential elements as K, P, S, Cl, Br, and I the algae present the maximum value, but they are also the richest of non-essential and toxic elements as Sr, As, Cd, Sn, Pb and Hg. The variation of elemental content from plant to plant is mainly attributed to the differences in botanical structure, as well as in the mineral composition of the soil in which the plants are cultivated. Other factors responsible for a variation in elemental content are preferential absorbability of the plant, use of fertilizers, irrigation water and climatic conditions. Tables 7 10 show for every group, the arithmetical mean and standard deviation for the concentration of all the elements Table 8 Arithmetical mean, standard deviation, minimum and maximum value (mg kg 1 dry) of essential elements (micro and trace) in the medicinal plants selected in this study. Part used Cr Mn Fe Co Ni Cu Zn Leaves Mean±σ 22.9 ± ± ± ± ± ± ±16.0 Minimum b b Maximum Flowers Mean±σ 2.2 ± ± ± ± ± ± ±4.9 Minimum b b Maximum Seeds Mean±σ 3.1 ± ± ± ± ± ± ±6.6 Minimum b b Maximum Roots Mean±σ 3.1 ± ± ±125.5 b ± ± ±1.3 Minimum b2.0 b Maximum Fruits Mean±σ 2.2 ± ± ±55.2 b ± ± ±15.4 Minimum b Maximum Barks Mean±σ b ± ± ± ± ± ±80.2 Minimum b1.0 b Maximum Berries Mean±σ b2 28.5± ±23.9 b ± ± ±15.7 Minimum b b Maximum Thallus Mean±σ 6.7 ± ± ± ± ± ± ±7.2 Minimum b b Maximum

6 D. Desideri et al. / Microchemical Journal 95 (2010) Table 9 Arithmetical mean, standard deviation, minimum and maximum value (mg kg 1 dry)of essential elements (halogens) in the medicinal plants selected in this study. Part used Cl Br I Leaves Mean±σ ± ± ±0.6 Minimum Maximum Flowers Mean±σ ± ± ±0.4 Minimum Maximum Seeds Mean±σ ± ± ±1.6 Minimum Maximum Roots Mean±σ ± ± ±0.7 Minimum Maximum Fruits Mean±σ 487.8± ± ±0.7 Minimum 32.4 b Maximum Barks Mean±σ 94.8 ± ± ±0.4 Minimum b20.0 b Maximum Berries Mean±σ 537.9± ± ±0.5 Minimum b20.0 b Maximum Thallus Mean±σ ± ± ± Minimum Maximum determined in this study. For the element concentrations below the detection limit, MDA was considered. Tables 11 and 12 show for Elettaria cardamom and Glycyrrhiza glabra a comparison between the concentration of some elements obtained by other authors using different techniques as Neutron Activation Analysis (NAA) and Atomic Absorption Spectroscopy (AAS). The data show that, for three samples of G. glabra coming from Italy, Algeria and India, the content of the different elements is often similar. However, it is difficult to draw conclusions by extrapolating data from plants collected in different zones. Among the many factors and parameters that can influence the concentration of elements in an organism, we should not underestimate all the factors affecting the area in question. Table 11 Comparison between the concentrations (mg kg 1 ) of some elements obtained by using different techniques for Elettaria cardamomum. Element 4. Conclusion This paper by EDPXRF (from unknown country) K Ca Cl Fe Mn Co b Cu Al b Ni Zn Cr Cd b Pb Hg b Rajurkar 1997 [7] by NAA and AAS (from India) A total of 23 elements (essential, non-essential and toxic) have been determined by polarised X ray fluorescence spectrometer (EDPXRF) in 35 medicinal plants used in Italy. The accuracy and precision of the technique were assured by analysing the Standard reference material. The use of the EDPXRF technique for the analysis of biological samples provides an essential tool for ascertaining the elemental composition of medicinal plants. The role of the elements determined in the body metabolism has been well established and the therapeutic action of medicinal plants through the alteration of metabolic processes has been identified. Although the direct linkage between elemental concentration in plants and their reported curative potentials is yet to be established, information on the levels of inorganic elements in plants is important in understanding the pharmacological and toxicological actions of medicinal plants in general. The results obtained in the analysis of some medicinal plants showed the presence of essential elements that could enhance the curative process of ill health, as well as the presence of potentially toxic elements. Table 10 Arithmetical mean, standard deviation, minimum and maximum value (mg kg 1 dry) of non-essential elements in the medicinal plants selected in this study. Part used Al Rb Sr Cd Sn Pb Leaves Mean±σ ± ± ± ± ± ±1.0 Minimum b b0.5 b Maximum Flowers Mean±σ ± ± ± ± ± ±0.2 Minimum b b0.5 b Maximum Seeds Mean±σ b ± ±16.0 b ± ±0.2 Minimum b0.1 b0.1 Maximum Roots Mean±σ ± ± ± ± ± ±0.3 Minimum b b Maximum Fruits Mean±σ ± ± ±30.2 b ± ±0.5 Minimum b b Maximum Barks Mean±σ ± ± ± ± ± ±0.6 Minimum b b Maximum Berries Mean±σ b ± ±13.0 b ± ±0.2 Minimum Maximum Thallus Mean±σ b ± ± ± ± ±1.9 Minimum b Maximum

7 180 D. Desideri et al. / Microchemical Journal 95 (2010) Table 12 Comparison between the concentrations (mg kg 1 ) of some elements obtained by different authors for Glycyrrhiza glabra. Element This paper By EDPXRF (from Italy) Rajurkar 1997 [7] by NAA and AAS (from India) Lamari 2008 [3] by NAA (from Algeria) K Ca Mg Fe Cl Mn b Co b Cu Al b Ni Zn Cr b Pb Hg b Cd b Rb Br I Sr Attempts are under progress by the authors in order to understand the exact relation between elemental content of these medicinal plants and their therapeutic proprieties. References [1] K. Chan, Some aspects of toxic contaminants in herbal medicines, Chemosphere 52 (2003) [2] N.K. Devi, N.H. Sarma, S. Kumar, Estimation of essential and trace elements in some medicinal plants by PIXE and PIGE techniques, Nuclear Instruments and Methods in Phisycs Research B 266 (2008) [3] Z. Lamari, S. Landsberger, J. Braisted, H. Neggache, R. Larbi, Trace element content of medicinal plants from Algeria, Journal Radioanalytical and Nuclear Chemistry 276 (1) (2008) [4] J. Barnes, Reports on complementary health care symposium, Pharmaceutical Journal 258 (1997) [5] L.A. Dim, I.I. Funtua, A.O. Oyewale, F. Grass, I.M. Umar, R. Gwozdz, U.S. Gwarzo, Determination of some elements in Ageratum conyziodes, a tropical medicinal plant, using instrumental neutron activation analysis, Journal of Radioanalytical and Nuclear Chemistry 261 (1) (2004) [6] N.S. Rajurkar, B.M. Pardeshi, Analysis of some herbal plants from India used in the control of diabetes mellitus by NAA and AAS techniques, Applied Radiation and Isotopes 48 (8) (1997) [7] N.S. Rajurkar, M.M. Damame, Mineral content of medicinal plants used in the treatment of diseases resulting from urinary tract disorders, Applied Radiation and Isotopes 49 (7) (1998) [8] V. Angelova, R. Ivanova, V. Delibaltova, K. Ivanov, Bio-accumulaton and distribution of heavy metals in fiber crops, Industrial crops and products 19 (2004) [9] S. Haider, V. Naithani, J. Barthwal, P. Kakkar, Heavy metal content in some therapeutically important medicinal plants, Bulletin of Environmental Contamination and Toxicology 72 (2004) [10] D.R. Baldwin, W.J. Marshall, Heavy metal poisoning and its laboratory investigation, Annals of Clinical Biochemistry 36 (1999) Acknowledgment The authors are very grateful to Dr S. Degetto of the CNR-ICTIMA (Padua, Italy) for his cooperation in this research.

8 ID Title Pages Determination of essential and non-essential elements in some medicinal plants by polarised X ray fluorescence spectrometer (EDPXRF) 7