RISK ASSESSMENT OF SOME HERBAL POWDERS AND HERBAL FORMULATIONS CONTAMINATED WITH HEAVY METALS

RISK ASSESSMENT OF SOME HERBAL POWDERS AND HERBAL FORMULATIONS CONTAMINATED WITH HEAVY METALS

Meena Deswal ¹, Pawan Deswal ² and J. S. Laura ^{* 1}

Department of Environmental Sciences ¹, Maharshi Dayanand University, Rohtak - 124001, Haryana, India.

Department of AYUSH ², Community Health Center, Village Dubaldhan, Jhajjar, Panchkula - 134109, Haryana, India.

ABSTRACT: Ten herbal medicines, Four herb choornam (Trikatu, Hingwashtak, Triphala and sitopladi) and five herbal compounds - Kutajghan Vati, Gandhak Rasayan, Sarivadi Vati, Chanderprabha Vati, Shankh Vati were tested for levels of heavy metals (Lead, copper, cadmium, iron, chromium, manganese, nickel and zinc). Both herbal extracts and herbal formulations showed the presence of heavy metals. Concentrations were higher in the herbal formulations as compared to herbal extracts. The intake of the heavy metals has been calculated by taking into account the recommended daily dose of the given Ayurvedic medicines and their calculated average daily dose (ADD). The paper discusses the significance of these quantities regarding calculated daily limit given by various international food and drug administration agencies. Iron, zinc, and copper are classified as micro-nutrients, and these metals have been reported to be deficient in the diet. The prescribed medication of tested Ayurvedic medicines provides the required intake of these micronutrients. The study concludes that the tested Ayurvedic medicines are not only safe regarding heavy metal intake but apart from their therapeutic use they are also beneficial as they supply essential minerals most importantly iron which is usually deficient in the diet.

Heavy metals, Average daily dose, Calculated daily limits, Ayurvedic medicine

INTRODUCTION: Ayurvedic is a system of medicine of Indian origin. Ayurvedic medicines originated in India more than 2000 years ago and relied heavily on herbs and their formulations. It is known to be an upveda of Atharva Veda. WHO (world health organization) estimates that 80% of the world’s population relies on these ‘Alternative’ plant-based medicines as their primary medical intervention ^{1, 2}. Approximately 70 - 80% of India's population use Ayurveda through more than one-half million Ayurvedic practitioners working in 860 Ayurvedic hospitals and 22100 clinics ^3-5.

Ayurvedic medicines being prepared from herbs are usually considered safe and free from side effects. Considering the complexity of these drugs, their inherent biological variation it becomes necessary to evaluate their efficacy, safety and quality ⁶. As per Indian Ayurvedic Product Market Forecast & Opportunities report, Global Ayurvedic Market in 2015 was accounted for $3,428.0 million and is expected to reach $9,791.0 million by 2022 growing at a compound annual growth rate of 16.0% during 2015-2022.

Due to heavy demand of herbal medicines natural resources of these herbs have depleted, so to meet the increasing demand, the medicinal herbs are cultivated on farms using standard agronomic practices which require input of fertilizers, pesticides, fungicides etc. to provide nutrition, protection from pests and diseases and to maintain high productive level ^{7, 8, 9}.

It’s well documented that chemical fertilizers and pesticides contain toxic substances which are taken up and accumulated in the various parts of the medicinal herbs. One such group of toxic substances is heavy metals. Ayurvedic formulations prepared using such herbs are likely to contain heavy metals taken up from the growth media ^10-16.

Heavy metal concentration in Ayurvedic medicines is of special concern in today’s time, as the use of Ayurvedic medicines is increasing, and one of the most important reasons for heavy metal contamination is pollution from various sources. Also, air born heavy metals may be sources of foliar contamination, at least for lead ¹⁷ and cadmium ¹⁸. Since contamination of herbs with heavy metals cannot be avoided as heavy metals are naturally present in the soil media as well as additional contamination from anthropogenic sources.

The Ayurvedic formulations contaminated with heavy metals can be said to be an unavoidable evil, as these heavy metals cannot be removed from the herbals and preparations. Since, 1978 at least 55 cases of heavy metal intoxication associated with Ayurvedic HMP (herbal medicinal preparations) in adults and children have been reported in the USA and abroad ¹⁹. Hence, some international agencies have come out with limits of daily dietary intake for the various heavy metals.

The US EPA (Environment protection agency, ASTDR (Agency for Toxic Substances and Disease Registry) has compiled priority list in 2001 called as “TOP 20 Hazardous Substances”. The heavy metals arsenic, lead, mercury, and cadmium are ranked 1^st, 2^nd, 3^rd, and 4^th respectively ²⁰. The various agencies like EPA, ATSDR, FDA (Food and drug agency) have made different criteria’s. EPA has established a reference dose” (RfD) for inorganic arsenic, cadmium, and methylmercury. ATSDR within the U.S. Department of Health and Human Services also has established and maintains “minimal risk levels “(MLRs) for oral consumption of arsenic, cadmium, and methylmercury ²¹. FDA has stated allowable level for Arsenic, Cadmium, Lead and Mercury in bottled drinking water.  Some works on the estimation of heavy metals in herbal medicines are discussed in Table 1.

Objective: To determine the level of various heavy metals in four herbal powder and five herbal compounds formulations and to examine the results regarding toxicity levels in the prescribed dosage of test herbs, formulations and compare with the calculated daily limit and average daily dose (ADD) set by the international agencies.

TABLE 1: ANALYSIS OF HEAVY METALS IN HERBS AND HERBAL MEDICINES

MATERIALS AND METHODS:

Material: The herbs and formulations were collected from reputed registered Ayurvedic stores.

The following samples were taken for heavy metal analysis Table 2.

TABLE 2: HERBAL COMPOUND, COMPOSITION, SCIENTIFIC NAME AND MEDICINAL PROPERTIES

Estimation of Heavy Metals: Samples were dried in a hot air oven at 60 ºC for 4 h. Dried samples were ground, and 1 gram of sample was digested in an acid mixture of nitric acid and hydrochloric acid in ratio of 1:3 (Aquaregia). The digested samples were cooled and filtered through a glass fiber filter. The final volume made to 25 ml with distilled water. The filtered samples were subjected to analysis for heavy metals using a double beam Atomic Absorption Spectrophotometer (Electronic Corporation of India Ltd., (ECIL), model AAS4141). Calibration curves of each metal were prepared by dilution of 1000 mg /L standard stock solution of the metals. The absorbance readings obtained were then calculated using the equations generated from the curves for each metal.

Risk Assessment: Daily ingestion of heavy metal through medication was calculated according to equation 1.

C = A / B   ……(1)

A= Concentration of heavy metal in sample (µg/gm); B= Capsule/ tablet weight in gram; C= Concentration of heavy metal in Capsule/ tablet (µg).

Daily ingestion of heavy metal = C × Prescribed a number of capsules/ tablets per day.

Average daily dose (ADD) calculation is recommended by the joint FAO / WHO Expert Committee on Food Additives ^27-29 for the risk assessment of heavy metals in Ayurvedic medicines and is computed according to Eq. (2)

ADD = (CH × ID × EF × ED) / (BW × AT)….(2)

Where ADD is average daily dose (µg/kg/day), CH is the concentration of toxic metals (µg/gm), ID is the ingestion dose (mg or gram/day), EF is the exposure frequency (taken as 60 days/year), ED is the exposure duration (48.35 Year), BW is the body weight (kg), and AT is the average lifespan, it has been taken as 68.35 years for both male and female of Indian origin ³⁰. The average weight was taken as 63.05 kg for male and 52.6 kg for female ³¹. The CH value was based on the recommended daily dose of the Ayurvedic medicines.

TABLE 3: CONCENTRATION OF HEAVY METALS IN THE AYURVEDIC MEDICINE SAMPLES

BDL: Below detectable limit.

TABLE 4: HEAVY METALS CONCENTRATION IN THE RECOMMENDED DAILY DOSE

Recommended dose- * 3g bid, ** 250 mg bid.

TABLE 5: AVERAGE DAILY DOSE (ADD) µg/kg/DAY OF HEAVY METALS FOR INDIAN MALE

 TABLE 6: AVERAGE DAILY DOSE (ADD) µg/kg/day, OF HEAVY METALS FOR INDIAN FEMALE

TABLE 7: CURRENT QUANTITATIVE HEAVY METAL LIMITS OF U.S. AGENCIES

FDA; Food and Drug Administration, EPA; Environmental Protection Agency, IRIS; Integrated risk information system; ATSDR; Agency for Toxic Substances and Diseases Registry. Source- AHPA., 2009

TABLE 8: HEAVY METAL LIMITS FOR CANADA’s NATURAL HEALTH PRODUCTS ³²

TABLE 9: CLINICAL IMPLICATIONS OF NUTRITIONAL TRACE ELEMENTS ³³

RESULTS AND DISCUSSION: Represented in Table 3 are the concentrations of the various heavy metals in the tested Ayurvedic preparations. In all the samples the heavy metals have been detected in varying quantities. Presence of heavy metals in Ayurvedic preparations has been reported in earlier works as well ^34-40. Iron in the Ayurvedic preparations (Tablet) has been detected in large quantity as compared to the powder, among the Sarivadi vati, Chanderprabha vati, Kutajghan vati and shankh vati have the higher concentration of the heavy metal. The highest concentration of copper, zinc, and manganese were found in Chanderprabha vati, Sarivadi vati, and Shankh vati respectively.

In Table 4 are presented the calculated values of the heavy metals in the capsules and tablet standard presentation of the products. Table 7 gives the concentration of heavy metal intake in the prescribed daily dose of the herbal extracts and Ayurvedic preparations. Table 5 and Table 6 give the average daily dose of the studied Ayurvedic products for male and female respectively. The average daily dose represents the amount of the intake calculated for the whole lifespan of an individual, and its value is less than the daily intake calculated by the recommended dose ⁴¹.

Also, the ADD of males was less than females. The daily intake of the heavy metals through the prescribed daily dose of these Ayurvedic medicines, as well as the calculated average daily dose, are compared with the Calculated Daily Limit in dietary intake given by the American and Canadian agencies as given in Table 7 and Table 8, it is observed that the quantities ingested are within limits prescribed by these agencies for both males and females.

Hence, these Ayurvedic medicines can be considered to be safe. Moreover, some of the heavy metals such as Iron, zinc copper, manganese, chromium have been reported to be essential for good health Table 9. However, these metals have been reported to be deficient in the diet ⁴² and required to be made up through the use of supplements. However, the tested herbal medicines contain these nutrients and consumption of these medicines makes up for the deficiency of these minerals in the diet.

CONCLUSION: The tested Ayurvedic medicines are not only safe regarding heavy metal intake but apart from their therapeutic use they are also beneficial as they supply some of the essential minerals most importantly iron which is usually deficient in the diet. These minerals may also have a synergetic effect on the activity of these Ayurvedic medicines.

ACKNOWLEDGEMENT: Dr. Meena Deswal is thankful to M.D University Rohtak for financial assistance inform of University Research Scholarship.

CONFLICT OF INTEREST: There is no conflict of interest of any sort.

REFERENCES:

1. Chan K: Some aspects of toxic contaminants in herbal medicines. Chemosphere 2003; 52: 1361-71.
2. Robert BS, Stefanos NK, Janet P, Michael JB, David ME and Roger BD: Heavy metal content of Ayurvedic herbal medicine products. J. American Med. Assocn 2004; 292(23): 2868-73.
3. Mafuva C and Marima-Matarira HT: Towards professionalization of traditional medicine in Zimbabwe: a comparative analysis to the South African policy on traditional medicine and the Indian Ayurvedic system. Int J Herb Med 2014; 2: 154-161.
4. Sen S and Chakraborty R: Revival, modernization and integration of Indian traditional herbal medicine in clinical practice: importance, challenges and J Trad Complementary Med 2017; 7: 237-244.
5. Gogtay NJ, Bhatt HA, Dalvi SS and Kshirsagar NA: The use and safety of non-allopathic. Indian medicines. Drug Saf 2002; 25: 1005-19.
6. Maria R, Gomez SC, Lorena LS, Maria FS and Lui DM: Determination of heavy metals for the quality control in Argentinean herbal medicines by ETAAS and ICP-OES. Food chem. Toxico. 2007; 45: 1060-64.
7. Kan WL, Ma B and Lin G. Sulfur fumigation processing of traditional Chinese medicinal herbs: beneficial or detrimental? Front Pharmacol 2011; 2(84): 1-7.
8. WHO: World Health Organization guidelines for assessing the quality of herbal medicines concerning contaminants and residues 2007; 1-35.
9. Yu IS, Lee JS, Kim SD, Kim YH, Park HW, Ryu HJ, Lee JH, Lee JM, Jung K, Na C, Joung JY and Son CG: Monitoring heavy metals, residual agricultural chemicals and sulfites in traditional herbal decoctions. BMC Complementary and Alternative Medicine 2017; 17: 154.
10. Nauri J, Khorasani N, Lorestani B, Karomi M, Hassani AH and Yousefi, N : Accumulation of heavy metals in soil and uptake by plant species with phytoremediation potential. Environmental Earth Sciences 2009; 59(2): 315-323.
11. Jyoti B, Nair S and Kakkar P: Heavy metal accumulation in medicinal plants collected from environmentally different sites. Biomed Environ Sci 2008; 21: 319-324.
12. Wenzel WW and Jockwer F: Accumulation of heavy metals in plants grown on mineralized soils of the Austrian Alps. Environmental Pollution 1999; 104(1): 145-155.
13. Slaveska R, Spirevska I, Stafilov T and Ristov T: The content of trace metals in some herbal teas and their aqueous extracts. Acta Pharm 1998; 48: 201-209.
14. Lasat M: Phytoextraction of metals from contaminated soil: a review of plant/soil/metal interaction and assessment of pertinent agronomic issues. Journal of Hazardous Substance Research 2000; 2(5): 1-25.
15. Gaur A and Adholeya A: Prospects of arbuscular mycorrhizal fungi in phytoremediation of heavy metal contaminated soils. Current Science 2004; 86(4): 528-534.
16. Anon: Lead,  electronic  Version, WHO Regional Office for Europe: Copenhagen, Denmark 2008a; Chapter  7: 3
17. Anon: Cadmium, electronic Version, WHO Regional Office for Europe: Copenhagen, Denmark 2008 b; Chapter 6.3: 3.
18. Saper RB, Kales SN, Paquin J, Burns MJ, Eisenberg DM, Davis RB and Phillips RS: Heavy metal Content of Ayurvedic Herbal Medicine Products, JAMA 2004; 292: 2868-2873.
19. Das SK, Grewal AS and Banerjee M: A brief review: Heavy Metal and their Analysis, Int. Journal of Pharmaceutical Sciences Review and Research Vol.11/1/art-003 2011.
20. Gogtay NJ, Bhatt HA, Dalvi SS and Kshirsagar NA: The use and safety of non-allopathic Indian medicines. Drug Safety 2002; 25: 1005-1019.
21. Ting A, Chow Y and Tan W: Microbial and heavy metal contamination in commonly consumed traditional Chinese herbal medicines. Journal of Traditional Chinese Medicine 2013; 33(1): 119-124.
22. Wu X and Xub J: Heavy metals contamination status and analyses of traditional Chinese medicine. Asian Journal of Chemistry 2013; 25(1): 19-22.
23. Nkansah MA, Hayford AT, Borquaye LS and Ephraim HJ: Heavy metal contents of some medicinal herbs from Kumasi, Ghana. Cogent Environmental Science 2016; 2: 1-8.
24. Dghaim R, Khatib SA, Rasool H and Khan MA: Determination of heavy metals concentration in traditional herbs commonly consumed in the Unites Arab Emirates. Journal of Environmental and Public Health 2015; 1-6.
25. Edward ME, Rajmund M, Nicoleta M and Marcel: Chemical risk due to heavy metal contamination of medicinal plants. Hop and Medicinal Plants 2016; 1-2.
26. Mishra SN: RasRatan Samuchchayah of acharya Shree vagbhat 2011b; 20: 466
27. Report of the Joint FAO/WHO consultation of food consumption and exposure assessment of chemicals. Geneva: WHO Press 1997; 10-4.
28. Chauhan G and Chauhan UK: Human health risk assessment of heavy metals via dietary intake of vegetables grown in wastewater irrigated area of Rewa, India. Int. Jou of Scientific and Research Publication 2014; 4(9): 1-9.
29. Kacholi DS and Sahu M: Levels and Health Risk Assessment of Heavy Metals in Soil, Water and Vegetables of Das es Saleam, Tanzania. Journal of Chemistry 2018; Article ID 1402674: 9.
30. World Bank: Life expectancy and Health life expectancy data by WHO region 2016.
31. LIC of India: Accepted as a standard weight chart all over India 2008.
32. WHO: Trace elements in human nutrition and health. World Health Organization 1996.
33. Dutta KT and Mukta V: Trace Elements. Medicine Update 2012; 22: 353-357.
34. Breeher L, Gerr F and Fuortes L: A case report of adult lead toxicity following use of Ayurvedic herbal medication. Journal of Occupational Medicine and Toxicology 2013; 8: 26. http://www.occup-med.com/ content/8/1/26
35. Saper RB, Kales SN, Paquin J, Burns MJ, Eisenberg DM, Davis RB and Phillips RS: Heavy metal Content of Ayurvedic Herbal Medicine Products, JAMA 2004; 292: 2868-2873.
36. Ernst E: Heavy metals in traditional Indian remedies. Eur. J. Clin. Pharmacol 2002; 57: 891-6.
37. Li SP, Zhao J and Yang B: Strategies for quality control of Chinese medicines. J. Pharm. Biomed. Anal 2011; 55(4): 802-9.
38. Zhang J, Wider B, Shang H, Li X and Ernst E: Quality of herbal medicines: challenges and solutions. Complement Ther Med. 2012; 20(1-2): 100-6.
39. Sarma H, Deka S, Deka H and Saikia RR: Accumulation of heavy metals in selected medicinal plants. Rev Environ Contam Toxicol.2011; 214: 63-86.
40. Posadzki P, Watson L and Ernst E: Contamination and adulteration of herbal medicinal products (HMPs): an overview of systematic reviews. Eur J Clin Pharmacol 2013; 69(3): 295-307.
41. Levine M, Michalic J, Runa AM, French, RNE and Brooks DF: Heavy Metal contaminants in Yerberia Shop Products, J.Med. Toxicol 2013; 9(1): 21-24.
42. WHO: Worldwide Prevalence of Anemia 1993-2005: WHO Global Database on Anemia 2008.
    

    ---

    How to cite this article:

    Deswal M, Deswal P and Laura JS: Risk assessment of some herbal powders and herbal formulations contaminated with heavy metals. Int J Pharm Sci & Res 2019; 10(1): 393-00. doi: 10.13040/IJPSR.0975-8232.10(1).393-00.

    ---

    All © 2013 are reserved by International Journal of Pharmaceutical Sciences and Research. This Journal licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.

    ---