Scientific Studies

Toxicology Studies

Toxicology is broadly defined as the study of adverse effects of chemicals on human beings. Generally, when people refer to toxicology studies, they tend to migrate toward discussions of carcinogenic effects. Many millions of dollars in research and hundreds of independent assessments have determined that the use of 2,4-D does not cause cancer and the herbicide can be used safely according to label directions for a variety of lawn, turf, industrial, forestry and agricultural applications. The following are some of the paramount studies in the area of 2,4-D toxicology research demonstrating this fact.

Health Canada Pest Management Regulatory Agency. Re-evaluation Decision (2,4-Dichlorophenoxy)acetic Acid [2,4-D]. RVD2008-11, 2008.
Bus, J.S. and Hammond, L.E., Regulatory Progress, Toxicology, and Public Concerns with 2,4-D: Where do we Stand after Two Decades? Crop Protection 26 (2007) 266-269.
Carmichael, N.G. et al., Agricultural Chemical Safety Assessment: A Multisector Approach to the Modernization of Human Safety Requirements. Crit. Rev. Toxicol. 36:1–7, 2006.
Cooper, R.L. et al., A Tiered Approach to Life Stages Testing for Agricultural Chemical Safety Assessment. Crit. Rev. Toxicol. 36:69–98, 2006.
Ross, R.H. et al., Dermal absorption of 2,4-D: A Review of Species Differences. Regulatory Toxicology and Pharmacology 41 (2005) 82-91.
U.S. Environmental Protection Agency. Reregistration Eligibility Decision for 2,4-D. Office of Pesticide Programs. EPA 738-R-05-002, 2005.
Timchalk, C., Comparative Inter-Species Pharmacokinetics of Phenoxyacetic Acid Herbicides and Related Organic Acids - Evidence that the Dog is Not a Relevant Species for Evaluation of Human Health Risk. Toxicology 200 (2004) 1-19.
Van Ravenzwaay, B. et al., Comparative Metabolism of 2,4-dichlorophenoxyacetic Acid (2,4-D) in Rat and Dog. Xenobiotica, August 2003, Vol. 33, No. 8, 805-821.
De Roos, A.J. et al., Integrative Assessment of Multiple Pesticides as Risk Factors for Non-Hodgkin's Lymphoma Among Men. Occup Environ Med. 2003;60e11.
Dost, F.N., Toxicology and Potential Health Risk of Chemicals that May Be Encountered by Workers Using Forest Vegetation Management Options - Part III, Risk to Workers Using 2,4-D Formulations. Forest Practices Branch, BC Ministry of Forests, 2003.
Garabrant, D.H. and Philbert, M.A., Review of 2,4-Dichlorophenoxyacetic Acid (2,4-D) Epidemiology and Toxicology. Critical Reviews in Toxicology 32(4):233-257, 2002. (Abstract only)
Gold, L.S., et al., Misconcptions About the Causes of Cancer. Human and Environmental Risk Assessment: Theory and Practice. D. Paustenbch, ed., New York: John Wiley & Sons, pp. 1415-1460 (2002).
Kennepohl, E. and Munro, I.C., Chapter 72 Phenoxy Herbicides (2.4-D). Handbook of Pesticide Toxicology, Vol 2, Chapter 72.6. Agents and Toxic Actions. Academic Press, New York, NY:1623-1638, 2001. (Abstract only)
Charles, J.M. et al., Developmental Toxicity Studies in Rats and Rabbits on 2,4-Dichlorophenoxyacetic Acid and its Forms. Toxicological Sciences, 60, 121-131, 2001.
Charles, J.M. et al., Ames Assays and Unscheduled DNA Synthesis Assays on 2,4-Dichlorophenoxyacetic Acid and its Derivatives. Mutation Research 444 (1999): 207-216.
Charles, J.M. et al., In Vivo Micronucleus Assays on 2,4-Dichlorophenoxyacetic Acid and its Derivatives. Mutation Research 444 (1999) 227-234. 1999.
Gollapudi, B.B. et al., Evaluation of the Genotoxicity of 2,4-dichlorophenoxyacetic Acid and its Derivatives in Mammalian Cell Cultures. Mutation Research 444 (1999) 217-225.
Acquavella, J. et al., Cancer among Farmers: a Meta-Analysis. Annals of Epidemiology, 8:64-74, 1998. (Abstract only)
Ritter, L. et al., Report of a Panel on the Relationship between Public Exposure to Pesticides and Cancer, for the Ad Hoc Panel on Pesticides and Cancer. National Cancer Institute of Canada, Cancer, 80(10):2019-33, 1997.
Mattsson, J.L. et al., Single-Dose and Chronic Dietary Neurotoxicity Screening Studies on 2,4-Dichlorophenoxyacetic Acid in Rats. Fundamental and Applied Toxicology, 40, 111-119, 1997. (Abstract only)
WHO Pesticide Residues in Food – 1996. Part II - Toxicological Evaluations. FAO Plant Production and Protection Paper 140: 31-38; and WHO/PCS/97.1: 45-96.
Charles, J.M. et al., Chronic Dietary Toxcicity/Oncogenicity Studies on 2,4-Dichlorophenoxyacetic Acid in Rodents. Fundamental and Applied Toxicology, Vol.33 166- 172 (1996).
Charles, J.M. et al., Comparative Subchronic and Chronic Dietary Toxicity Studies on 2,4-Dichlorophenoxyacetic Acid, Amine and Ester in the Dog. Fundamental and Applied Toxicology, Vol. 29, Number 1:78-85 (1996).
Safe, Stephen H., Environmental and Dietary Estrogens and Human Health: Is there a Problem? Environmental Health Perspectives. Vol 103 No. 4: 346-351, 1995.
Munro, I.C. et al., A Comprehensive, Integrated Review and Evaluation of the Scientific Evidence Relating to the Safety of the Herbicide 2,4-D. J. Amer. Coll. Toxicol. Vol. 11, No. 5: 559-664, 1992.
Cantor, K.P. et al., Pesticides and Other Agricultural Risk Factors for Non-Hodgkins Lymphoma among Men in Iowa and Minnesota. Cancer Res 1992; 52: 2447-55 (see also Cantor, KP et al. letter to the editor, Cancer Res 1993; 53: 2421) (Abstract only)
Gorzinski, S.J. et al., Acute, Pharmacokinetic, and Subchronic Toxicological Studies of 2,4-Dichlorophenoxyacetic Acid. Fundamental and Applied Toxicology 9, 423-435 (1987).
Sauerhoff, M.W. et al., The Fate of 2,4-Dichlorophenoxyacetic Acid (2,4-D) Following Oral Administration to Man. Toxicology, 8 (1977) 3-11.
Feldmann, R.J. and Maibach, H.I., Percutaneous Penetration of Some Pesticides and Herbicides in Man. Toxicology and Applied Pharmacology 28, 126-132 (1974).