Document Type : Original Article

Authors

1 Department of Pharmacology and Toxicology, Faculty of Pharmacy, Federal University, Oye_Ekiti, Nigeria

2 ManProject Foundation, PortHarcourt, Nigeria

3 Department of Pharmacology and Toxicology, Faculty of Pharmacy, Bingham University, Karu, Nigeria

4 Department of Pharmacology and Toxicology, Faculty of Pharmacy, University of Uyo, Nigeria

5 Department of Human Physiology, College of Medicine and Health Sciences, Afe Babalola University, Ado-Ekiti, Nigeria

6 Department of Pharmacology, Therapeutics, and Toxicology, Lagos State University College of Medicine, Ikeja, Lagos, Nigeria

10.30476/jhsss.2021.93527.1457

Abstract

Background: Heavy metal contaminations of herbal formulations have constituted a public health challenge in the sub-Saharan Africa region and even in some developed nations. The study aimed to evaluate the public health concerns of chronic exposure to a polyherbal drug suspected to contain heavy metals. Methods: This is an experimental study. Heavy metals were measured using Solaar-Thermo-Elemental Atomic Absorption Spectrophotometer. Human health risk assessment was estimated by calculating the estimated daily intake, target, hazard quotient (THQ), health index (HI), carcinogenic risk (CR) of exposure to the polyherbal drug.
Results: The results showed the presence of metals in this order: Cd<Hg<As<Pb<Zn<Mn<Cu<Ni<Cr 1; HI for adolescents, adults, and geriatrics were >1. Ni and Cr had the highest cancer risk; total cancer risk was above the safe limit.

Conclusion: Since herbal medicines/dietary supplements are not under compulsory regulation by international, national, and local health regulatory authorities, these products must be manufactured using the highest manufacturing standards to ensure their safety among the end-users. Our findings suggest the likelihood of significant non-carcinogenic adverse health effects among adolescents, adults, and the geriatric population due to exposure to a mix of toxic metals, necessitating utmost caution on its chronic use. If policy formulations and implementations regarding the safety of herbal medicines and associated products prior to their circulation are ensured, public health will be protected and significantly improved.

Keywords

  1. Akerele O. Nature’s medicinal bounty: Don’t throw it away. World Health Forum. 1993;14:390-395.
  2. Saunders JE, Jastrzembski BG, Buckey JC, Enriquez D, MacKenzie TA, Karagas MR. Hearing loss and heavy metal toxicity in a Nicaraguan mining company: audiological results and case reports. Audiol Neurootolo. 2013;18(2):101-13. https://doi.org/10.1159/000345470.
  3. Tchounwou PB, Yedjou CG, Patlolla AK, Sutton DJ. Heavy metal toxicity and the environment. EXS. 2012;101:133-64. https://doi.org/10.1007/978-3-7643-8340_6.
  4. Wang XL, Sato T, Xing BS, Tao S. Health risks of heavy metals to the general public in Tianjin, China via consumption of vegetables and fish. Sci. Total Environ.2005;350:28-37. https://doi.org/10.1016/j.scitotenv.2004.09.044.
  5. Solaade A. Assorted herbal mixtures: herbs or poison? [Internet] 2015 [Cited 2021 Aug 22]. Available from:  https://parroteye.blogspot.com/2015/01/herbs-or-poison.html.
  6. Säumel I, Kotsyuk I, Hölscher M, Lenkereit C, Weber F, Kowarik I. How healthy is urban horticulture in high traffic areas? Trace metal concentrations in vegetable crops from plantings within inner city neighbourhoods in Berlin, Germany. Environ Pollut. 2012;165:124-32. https://doi.org/10.1016/j.envpol.2012.02.019.
  7. United States Environmental Protection Agency. Recommended protocols for measuring conventional water quality variables and metals in fresh water of the Puget Sound, 1200 6th Avenue Seattle, WA 98101. [Internet] 1900 [Cited 2021 Aug 22]. Available from: https://www.psat.a.gov/Publications/protocols/protocol_pdfs
  8. Orisakwe OE, Dagur EA, Mbagwu HOC, Udowelle NA, Offor SJ. Levels of some heavy metals in vegetables from artisanal mining sites of Dilimi River, Bukuru and Barkin Ladi North Central Nigeria: any public health concern? Rocz Panstw Zakl Hig. 2018;69(4):335-45. https://doi.org/10.32394/rpzh.2018.0038.
  9. United States Environmental Protection Agency.  Risk Assessment Guidance for Superfund. Volume 1. Human Health Manual – Part E, Supplemental Guidance for Dermal Risk Assessment. Office of Superfund Remediation and Technology Innovation, Washington, D.C: United State Environmental Protection Agency; 2004.
  10. Tripathi RM, Raghuanath R, Krishnamoorthy TM. Dietary intake of heavy metals in Bombay city, India J Sci Total Environ.1997;208(3):149-59. https://doi.org/10.1016/s0048-9697(97)00290-8.
  11. Orisakwe OE, Nduka JK, Amadi CN, Dike DO, Bede O. Heavy metals health risk assessment for population via consumption of food crops and fruits in Owerri, South Eastern Nigeria. Chem Century J.2012;6:77.
  12. Ekhator OC, Udowelle NA, Igbiri S, Asoumugha RN, Igweze ZN, Orisakwe OE. Safety evaluation of potential toxic metals exposure from street foods consumed in Mid-West Nigeria. J Environ Public Health. 2017;8458057. https://doi.org/10.1155/2017/8458057.
  13. Igbiri S, Udowelle NA, Ekhator OC, Asoumugha RN, Igweze ZN, Orisakwe OE. Edible mushrooms from Niger Delta, Nigeria with heavy metal levels of public health concerns: a human health risk assessment. Recent Pat Food Nutr Agric.2018;9(1):31-41. https://doi.org/10.2174/22122798409666171129173802.
  14. Igbiri S, Udowelle NA, Ekhator OC, Asoumugha RN, Igweze ZN, Orisakwe OE. Polycyclic aromatic hydrocarbons in edible mushrooms from Niger Delta, Nigeria: carcinogenic and non-carcinogenic health risk assessment. Asian Pac J Cancer Prev. 2017;18(2):437-47. https://doi.org/10.22034/AJPCP.18.2.437
  15. Udowelle NA, Igweze ZN, Asoumugha RN, Orisakwe OE. Health risk assessment and dietary exposure of polycyclic aromatic hydrocarbons (PAHs), lead and cadmium from bread consumed in Nigeria. Rocz Panstw Zakl Hig.2017;68(3):269-80.
  16. Harmanescu M, Alda LM, Bordean DM, Gogoasa I, Gergen I. Heavy metals health risk assessment for population via consumption of vegetables grown in old mining area; a case study: Banat County, Romania. Chem Cent J. 2011;5:64. https://doi.org/10.1186/1752-153X-5-64
  17. Integrated Risk Information System. Regional screening level (RSL) summary table 2015 [Cited 2021 Aug 24] Available from: https://www.epa.gov/iris_pdf/.
  18. Kamunda C, Mathuthu M, Madhuku M. Health risk assessment of heavy metals in soils from Witwaterssrand gold mining basin, South Africa. Int J Environ Res Public Health. 2016;13:633-44. https://doi.org/10.3390/ijerph3070663.
  19. United States Environmental Protection Agency. Exposure Factors Handbook. [Internet] 2011a [Cited 2021 Aug 26]. Available from:  https://cfpub.epa.gov/ncea/risk/recordisplay.cfm?deid=236252
  20. United States Environmental Protection Agency. USEPA regional screening level (RSL) summary table. [Internet] 2011b [Cited 2021 Aug 22]. Available from:  https://www.epa.gov/regshwmd/risk/human/index.html
  21. California Office of Environmental Health Hazard Assessment. Revised Draft: California Human Health Screening Level for Lead. [Internet] 2009 [Cited 2021 Aug 26]. Available from: https://oehha.ca.gov/risk/chhsl051809.html.
  22. United States Department of Energy. The Risk Assessment Information System (RAIS). USDOE Oak Ridge Operations Office, Tennessee: United States Department of Energy; 2011.
  23. Shah A, Niaz A, Ullah N, Rehman A, Akhlaq M, Zakir M et al. Comparative study of heavy metals in soil and selected medicinal plants. J Chem.2013;2013:621265. https://doi.org/10.1155/2013/621265.
  24. World Health Organization. Guidelines for the Safe Use of Waste Water, Excreta and Grey Water: Waste Water in Agriculture (Volume 2). Geneva: World Health Organization; 2006.
  25. World Health Organization. Health Risks of Heavy Metals from Long-range Transboundary Air Pollution – Joint Task Force on the Health Aspects of Long-range Transboundary Air Pollution. Geneva: World Health Organization; 2007.  
  26. WHO/FAO. Guidelines for the Safe Use of Waste Water and Food Stuff: Waste Water in Agriculture (Volume 3). Geneva: World Health Organization; 2013.
  27. WHO/FAO. General Standard for Contaminants and Toxins in Food and Feed (CODEX STAN 193 – 1995). Geneva: World Health Organization; 2015.
  28. United States Food and Drug Administration. Code of Federal Regulations (CFR) Title 21: Food for Human Consumption – Requirements for Specific Standardized Beverages. [Internet] 2018 [Cited 2021 Aug 30]. Available from: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=165.110
  29. Hassan Z, Anwar Z, Khattak KU, Islam M, Khan RU, Khattak JZK. Civic pollution and its effects on water quality of River Toi at district Kohat, NWFP. Res J Environ Earth Sci.2012;4(3):334-39.
  30. Asomugha RN, Udowelle NA, Offor SJ, Njoku CJ, Ofoma IV, Chukwuogor CC et al. Heavy metals hazards from Nigerian spices. Rocz Panstw Zakl Hig. 2016;67:309-14.
  31. Rehman K, Fatima F, Waheed I, Akash MSH. Prevalence of exposure of heavy metals and their impact on health consequences. J Cell Biochem. 2017;119(1):157-84. https://doi.org/10.1002/jcb.26234.
  32. Orisakwe OE. Lead and cadmium in public health in Nigeria: Physicians neglect and pitfall in patient management. New Am J Med Sci. 2014;6:61-70.
  33. Podsiki C. Chart of heavy metals, their salts and other compounds. [Internet] 2008 [Cited 2021 Aug 30]. Available from: https://www.conservation-us.org/docs/default-source/resource-guides/chart-of-heavy-metals-theirsalts-and-other-compounds-nbsp-pdf
  34. Ogwuegbu MO, Muhanga W. Investigation of lead concentration in the blood of people in the copper belt province of Zambia. J Environ. 2005;11:66-75.
  35. Agency for Toxic Substances and Disease Registry. Chromium toxicity: what are the physiologic effects of chromium exposure? [Internet] 2013 [Cited 2021 Aug 29]. Available from: https://www.atsdr.cdc.gov/csem/csem.asp?csem=10&po=10  
  36. Agency for Toxic Substances and Disease Registry. Toxicological Profiles, Toxic Substances Portal. Atlanta: Agency for Toxic Substances and Disease Registry; 2015.
  37. Liu J, Zhang XH, Tran H, Wang DQ, Zhu YN. Heavy metal contamination and risk assessment in water, paddy soil, and rice around an electroplating plant. Environ Sci Pollut Res. 2011;18(9):1623-32. https://doi.org/10.1007/s11356-011-0523-3.
  38. Liu X, Song Q, Tang Y, Li W, Xu J, Wu J et al. Human health risk assessment of heavy metals in soil-vegetable system: a multi medium analysis. Sci Total Environ.2013;(463-464):530-40. https://doi.org/10.1016/j.scitotenv.2013.06.064.