Skip to content
Licensed Unlicensed Requires Authentication Published by De Gruyter March 26, 2016

Determination of methanol in Iranian herbal distillates

  • Kobra Shirani , Faezeh Vahdati Hassani , Kamal Razavi Azar-Khiavi , Zohreh Samie Moghaddam and Gholamreza Karimi EMAIL logo


Background: Herbal distillates have been used as beverages, for flavoring, or as phytomedicines in many countries for a long time. Recently, the occurrence of blindness after drinking herbal distillates has created concerns in Iran. The aim of this study was to determine the concentrations of methanol in herbal distillates produced in Iran.

Methods: Eighty-four most commonly used herbal distillates purchased from herbal distillate factories were analyzed for methanol contents by gas chromatography and flame ionization detection, with ethanol as internal standard.

Results: In 15 herbal distillates, the methanol concentration was below the limit of quantitation. The methanol concentrations in all samples ranged from 43 to 277 mg/L. Forty-five samples contained methanol in excess of the Iranian standard. The maximum concentration was found in an herbal distillate of Mentha piperita (factory E) (277±12), and the minimum in a distillate of Carum carvi (factory B) (42.6 ± 0.5).

Conclusions: Since the 45 Iranian herbal distillates containing methanol levels were beyond the legal limits according to the Iranian standard, it seems necessary to monitor the amount of methanol and give a warning to watch out for the latent risk problem of methanol uptake, and establish a definitive relationship between the degree of intoxication observed and the accumulation of methanol in the blood.


The authors are thankful to the Vice Chancellor of Research, Mashhad University of Medical Sciences and Iran National Science Foundation (INSF) for financial support.

Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

Research funding: None declared.

Employment or leadership: None declared.

Honorarium: None declared.

Competing interests: The funding organization(s) played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.


1. Kulig K, Duffy JP, Linden CH, Rumack BH. Toxic effects of methanol, ethylene glycol, and isopropyl alcohol. Adv Emerg Nurs J 1986;6:14–29.Search in Google Scholar

2. Word Health Organisation (WHO). Environmental health criteria 196: methanol. Geneva: WHO, 1997. Available at: in Google Scholar

3. Soffritti M, Belpoggi F, Cevolani D, Guarino M, Padovani M, Maltoni C. Results of long‐term experimental studies on the carcinogenicity of methyl alcohol and ethyl alcohol in rats. Ann N Y Acad Sci 2002;982:46–69.10.1111/j.1749-6632.2002.tb04924.xSearch in Google Scholar

4. Bestic M, Blackford M, Reed M. Fomepizole: a critical assessment of current dosing recommendations. J Clin Pharmacol 2009;49:130–7.10.1177/0091270008327142Search in Google Scholar

5. Kraut JA, Kurtz I. Toxic alcohol ingestions: clinical features, diagnosis, and management. Clin J Am Soc Nephrol 2008;3:208–25.10.2215/CJN.03220807Search in Google Scholar

6. Blanco M, Casado R, Vazquez F, Pumar J. CT and MR imaging findings in methanol intoxication. Am J Neuroradiol 2006;27:452–4.Search in Google Scholar

7. Barceloux DG, Randall Bond G, Krenzelok EP, Cooper H, Allister Vale J. American Academy of Clinical Toxicology practice guidelines on the treatment of methanol poisoning. Clin Toxicol 2002;40:415–46.Search in Google Scholar

8. Von Burg R. Methanol. J Appl Toxicol 1994;14:309–13.10.1002/jat.2550140412Search in Google Scholar

9. Brent J, McMartin K, Phillips S, Aaron C, Kulig K. Fomepizole for the treatment of methanol poisoning. N Engl J Med 2001;344:424–9.10.1056/NEJM200102083440605Search in Google Scholar

10. Mangos TJ, Haas MJ. A spectrophotometric assay for the enzymatic demethoxylation of pectins and the determination of pectinesterase activity. Anal Biochem 1997;244:357–66.10.1006/abio.1996.9908Search in Google Scholar

11. Lea A. Enzymes in the production of beverages and fruit juices, enzymes in food processing. New York: Chapman and Hall, 1995:223–49.10.1007/978-1-4615-2147-1_7Search in Google Scholar

12. Mousavi SR, Namaei-Ghassemi M, Layegh M, Afzalaghaee M. Determination of methanol concentrations in traditional herbal waters of different brands in Iran. Iran J Basic Med Sci 2011;14:361–8.Search in Google Scholar

13. Barboza GE, Cantero JJ, Núñez C, Pacciaroni A, Ariza Espinar L. Medicinal plants: a general review and a phytochemical and ethnopharmacological screening of the native Argentine flora. Kurtziana 2009;34:365–7.Search in Google Scholar

14. Houghton PJ. The role of plants in traditional medicine and current therapy. J Altern Complement Med 1995;1:131–43.10.1089/acm.1995.1.131Search in Google Scholar

15. Solhi H, Delirrad M, Ghasempour Z, Hassanzadazar H, Roshani Y, Mohammadi D, et al. Determination of methanol content in herbal distillates produced in Urmia using spectrophotometry. Iran J Toxicol 2012;6:594–9.Search in Google Scholar

16. Rao VP. Extraction of essential oil and its applications. BTech thesis. Rourkela, Odisha: National Institute of Technology Rourkela, 2006.Search in Google Scholar

17. Onianwa P, Adetola I, Iwegbue C, Ojo M, Tella O. Trace heavy metals composition of some Nigerian beverages and food drinks. Food Chem 1999;66:275–9.10.1016/S0308-8146(98)00257-XSearch in Google Scholar

18. Paine A, Dayan A. Defining a tolerable concentration of methanol in alcoholic drinks. Hum Exp Toxicol 2001;20:563–8.10.1191/096032701718620864Search in Google Scholar PubMed

19. Tamura M, Uyama A, Mochizuki N. Development of a multi-mycotoxin analysis in beer-based drinks by a modified QuEChERS method and ultra-high-performance liquid chromatography coupled with tandem mass spectrometry. Anal Sci 2001;27:629–35.10.2116/analsci.27.629Search in Google Scholar PubMed

20. Gout E, Aubert S, Bligny R, Rébeillé F, Nonomura AR, Benson AA, et al. Metabolism of methanol in plant cells. Carbon-13 nuclear magnetic resonance studies. Plant Physiol 2000;123:287–96.10.1104/pp.123.1.287Search in Google Scholar PubMed PubMed Central

21. Rafizadeh A, NasiriFard R, Gazni MN, Haghshanas M, PoorMohammad FJBaL. The Effectiveness of Whole Concentration of Homemade Herbal Distillates on the Result of Qualitative Methanol Detection by the Chromotropic Acid Method. J Ornamental Plant 2013;3:105–9.Search in Google Scholar

22. James JT. Spacecraft maximum allowable concentrations for airborne contaminants. Johnson Space Center20584 1995Search in Google Scholar

23. Organisation Internationale De La Vigne Et Du Vin (OIV). Recueil des methods internationals d’analyse des vins et des mouts. Paris: Edition Officielle, 1990.Search in Google Scholar

24. Karimi G, Hasanzadeh M, Shahidi N, Samiei Z. Quantitative determination of methanol in plant water produced in Mashhad by spectrophotometry method. J Med Plant 2008;25:56–9.Search in Google Scholar

Received: 2015-6-15
Accepted: 2016-3-5
Published Online: 2016-3-26
Published in Print: 2016-6-1

©2016 by De Gruyter

Downloaded on 25.3.2023 from
Scroll Up Arrow