Concentration and sources of polycyclic aromatic hydrocarbons in some commercial herbal drugs used for cholera treatment in southwest Nigeria

Akintelu Sunday Adewale, Olugbeko Seyifunmi Charles, Folorunso Femi Adekunle, Oyebamiji Abel Kolawole, Folorunso Aderonke Similoluwa


The aim of this study was to investigate the cancer risk that could be incurred from the use of some anti-cholera herbal drugs sold in Southwest Nigeria. Three most popular anti-cholera herbal drugs were studied. The cancer risk estimation for the drugs at studied population ranges from 7.119 to 0.338 x 10-8 in children, 9.563 to 0.129 x 10-8 in preteen and 9.541 to 5.196 x 10-8 in adult. The cancer risk estimated values are below the USEPA set value 1 x 10-6. This established that the use of these herbal drugs might not lead to cancer if consumed at low dosage.


cancer risk; traditional medicine; cancer risk estimation; anti-diarrhea and toxicity

Full Text:



Adagbada OA, Adesida AA, Nwaokorie OF, Niemogha MT, Coker AO. Cholera epidemiology in Nigeria an overview. Pan Afr Med J. 2012; 59: 1–12.

Dalhat M, Isa A, Nguku P, Nasir S, Urban K, Abdulaziz M, Dankoli R, Nsubuga P, Poggensee G. Descriptive characterization of the 2010 cholera outbreak in Nigeria. BMC Public Health 2014;14(1):.

Dan-Nwafor C, Ogbonna U, Onyiah P, Gidado S, Adebobola B, Nguku P, Nsubuga P. A cholera outbreak in a rural north central Nigerian community: an unmatched case-control study. BMC Public Health 2019;19(1):.

Mengel M. Cholera in Africa: new momentum in fighting an old problem. Transactions of the Royal Society of Tropical Medicine and Hygiene 2014;108(7):391-392.

Mengel M, Delrieu I, Heyerdahl L, Gessner B. Cholera Outbreaks in Africa. Cholera Outbreaks 2014;:117-144.

Piarroux R, Faucher B. Cholera epidemics in 2010: respective roles of environment, strain changes, and human-driven dissemination. Clinical Microbiology and Infection 2012;18(3):231-238.

Ndon J, Udo S, Wehrenberg W. Vibrio-associated gastroenteritis in the lower Cross-River Basin of Nigeria.. Journal of Clinical Microbiology 1992;30(10):2730-2732.

Dan-Nwafor C, Ogbonna U, Onyiah P, Gidado S, Adebobola B, Nguku P, Nsubuga P. A cholera outbreak in a rural north central Nigerian community: an unmatched case-control study. BMC Public Health 2019;19(1):.

Galvão Rodrigues F, Costa J, Rodrigues F, Campos A. Study of the Interference betweenPlectranthusSpecies Essential Oils from Brazil and Aminoglycosides. Evidence-Based Complementary and Alternative Medicine 2013;2013:1-7.

Sanchez E, Garc�a S, Heredia N. Extracts of Edible and Medicinal Plants Damage Membranes of Vibrio cholerae. Applied and Environmental Microbiology 2010;76(20):6888-6894.

Senthilkumar PK, Reetha D. Bioactivity of Cassia auriculata methanol extract against human pathogenic bacteria and fungi. Int. J. Psy. Behav. Anal. 2, 2011;:1534–1538.

Taran M, Ghasempour HR, Shirinpour E. Antimicrobial activity of essential oils of Ferulago angulate subsp. carduchorum. Jundishapur J Microbiol 2010; 3: 10–14.

Ekeanyanwu RC, Njoku JO, Nwodu PO, Njokuobi AE. Analysis of Some Selected Toxic Heavy Metals in Some Branded Nigerian Herbal Products. J App. Pharm. Sci. 2013;3(4):088-091


Martena M, Van Der Wielen J, Rietjens I, Klerx W, De Groot H, Konings E. Monitoring of mercury, arsenic, and lead in traditional Asian herbal preparations on the Dutch market and estimation of associated risks. Food Additives & Contaminants: Part A 2010;27(2):190-205.

Orisakwe O. The role of lead and cadmium in psychiatry. North American Journal of Medical Sciences 2014;6(8):370.

Larsen JC, Larsen PB. Chemical carcinogens. In: Air Pollution and Health (Hester R, Harrison R, eds.). Cambridge, UK: The Royal Society of Chemistry, 1998; 33–56.

Agency for Toxic Substance and Disease Registry (ATSDR), Public Health Assessment Guidance Manual (Update), U.S. Department of Health and Human Services, Atlanta, GA, 2005 (January).

Ding X, Kaminsky L. HUMANEXTRAHEPATICCYTOCHROMESP450: Function in Xenobiotic Metabolism and Tissue-Selective Chemical Toxicity in the Respiratory and Gastrointestinal Tracts. Annual Review of Pharmacology and Toxicology 2003;43(1):149-173.

Ciecierska M, Obiedziński M. The GC-MS analysis of polycyclic aromatic hydrocarbons content in selected fruit and herbal teas kerlapolica 2009; (55) 2; 19-24

European Union, Commission Recommendation of 4 February 2005 on further investigation into the levels of polycyclic aromatic hydrocarbons in certain food, 2005 [Accessed on 12-05-2020]

Domínguez C, Sarkar S, Bhattacharya A, Chatterjee M, Bhattacharya B, Jover E, Albaigés J, Bayona J, Alam M, Satpathy K. Quantification and Source Identification of Polycyclic Aromatic Hydrocarbons in Core Sediments from Sundarban Mangrove Wetland, India. Archives of Environmental Contamination and Toxicology 2010;59(1):49-61.

Lijinsky W. The formation and occurrence of polynuclear aromatic hydrocarbons associated with food. Mutation Research/Genetic Toxicology 1991;259(3-4):251-261.

Agency for Toxic Substances and Disease Registry (ATSDR). Health Consultation, EPA FACILITY ID: OHN000510571 U.S. Department of Health and Human Services, Fostoria, Wood County, Ohio. February 2014.