Chronic dietary toxicity/oncogenicity studies on 2,4-dichlorophenoxyacetic acid in rodents.

  title={Chronic dietary toxicity/oncogenicity studies on 2,4-dichlorophenoxyacetic acid in rodents.},
  author={Jeffrey M. Charles and David M. Bond and T K Jeffries and Barry L. Yano and W. T. Stott and K A Johnson and Helen C. Cunny and R. D. Wilson and James S. Bus},
  journal={Fundamental and applied toxicology : official journal of the Society of Toxicology},
  volume={33 2},
  • J. CharlesD. M. Bond J. Bus
  • Published 1996
  • Medicine
  • Fundamental and applied toxicology : official journal of the Society of Toxicology
Forms of 2,4-dichlorophenoxyacetic acid (collectively known as 2,4-D) are herbicides used to control a wide variety of broadleaf and woody plants. Doses in the 2-year chronic/oncogenicity rat study were 0, 5, 75, and 150 mg/kg/day. The chronic toxicity paralleled subchronic findings, and a NOEL of 5 mg/kg/day was established. A slight increase in astrocytomas observed (in males only) at 45 mg/kg/day in a previously conducted chronic rat study was not confirmed in the present study at the high… 

Tables from this paper

Comparative metabolism of 2,4-dichlorophenoxyacetic acid (2,4-D) in rat and dog

The results show that the body burden of 2,4-D in dog is significantly higher than in rat for an equivalent dose, which is consistent with the increased sensitivity of dog to 2, 4-D toxicity.

Review of 2,4-Dichlorophenoxyacetic Acid (2,4-D) Epidemiology and Toxicology

The scientific evidence in humans and animals relevant to cancer risks, neurologic disease, reproductive risks, and immunotoxicity of 2,4-D was reviewed and no experimental evidence exists supporting the theory that 2, 4-D or any of its salts and esters damages DNA under physiologic conditions.

Sex-dependent differences in the disposition of 2,4-dichlorophenoxyacetic acid in Sprague-Dawley rats, B6C3F1 mice, and Syrian hamsters.

Kinetic analysis revealed significant differences in elimination and exposure parameters consistent with a greater ability to clear 2,4-D by male rats relative to females, which suggests that at equivalent doses, female rats are exposed to higher concentrations of 2, 4-D for a longer time than males and may be more susceptible to 2,3-D-induced toxicity.

Exposures to 2,4-Dichlorophenoxyacetic acid with or without endotoxin upregulate small cell lung cancer pathway

The data from the study provide the insights of the potential damage on lungs caused by 2,4-D and help to better understand the mechanism of this complex relation.

Investigation of 2,4 dichlorophenoxyacetic acid effects in different population of rat duodenum myenteric neurons.

The results suggest that the 2,4-D has a neurotoxic action in the neurons from the myenteric plexus, interfering in the myEnteric neuronal density, when different population of these neurons are compared.


The cytotoxic effects of exposure to low concentrations of the herbicide, 2,4dichlorophenoxyacetic acid (2,4-D) that are typically found in groundwater were investigated, in vitro, and cytotoxicity was induced directly by 2, 4-D, and not by the ‘inert ingredients’ in the commercial formulation.

A Systematic Review of Carcinogenic Outcomes and Potential Mechanisms from Exposure to 2,4-D and MCPA in the Environment

A comparison of biomonitoring data to oral equivalent doses calculated from bioassay data shows that environmental exposures are not sufficient to support a causal relationship and the combined evidence does not support a genotoxic mode of action.

Evaluation of myenteric neurons in the colon of rats exposed to 2,4 dichlorophenoxyacetic acid herbicide

  • Wagner NanniG. S. Porto R. B. Mari
  • Biology
    Journal of environmental science and health. Part. B, Pesticides, food contaminants, and agricultural wastes
  • 2022
The neurotoxic effects of 2,4-D in the myEnteric plexus influenced an increase in the general population of myenteric neurons in the colon, which may be related to the increased expression of the neurotransmitter acetylcholine by colocalization.



Comparative subchronic and chronic dietary toxicity studies on 2,4-dichlorophenoxyacetic acid, amine, and ester in the dog.

Comparing toxicity among representative forms of 2,4-D and their generally low toxicity following subchronic and chronic dietary exposure in the dog are indicated.

Chronic dietary toxicity study on 2,4-dichlorophenoxybutyric acid in the dog.

  • J. CharlesN. Leeming
  • Biology, Medicine
    Toxicological sciences : an official journal of the Society of Toxicology
  • 1998
The findings in this study indicate the general low toxicity of 2,4-DB following chronic dietary exposure in the dog and support a chronic no observed adverse effect level of 75 ppm.

Chronic toxicity of 2,4-dichlorophenoxyacetic acid in rats and dogs.

A Comprehensive, Integrated Review and Evaluation of the Scientific Evidence Relating to the Safety of the Herbicide 2,4-D

The available data indicate that the potential public health impact of 2,4-D, including the risk of human cancer, was negligible in the past and would be expected to be even smaller in the present and future.

Aging changes in CD-1 HaM/ICR mice reared under standard laboratory conditions.

Variability in tumor incidence among small groups if mice emphasized the need for adequate samples is found, as well as among mice that came to autopsy, is found.

New tables for multiple comparisons with a control.

The main purpose of the present paper is to give the exact tables for making two-sided comparisons, and a method is given for adjusting the tabulated values to cover the situation where the variance of the control mean is smaller than thevariance of the treatment means.

Transformations: Some Examples Revisited

This paper considers the particular problem of transforming data from the viewpoint of several aspects of a problem or several criteria by re-examining some specific published examples.

The Icr:Ha(ICR) mouse: a current account of breeding, mutations, diseases and mortality

This stock of albino mice is minimally inbred, and has been rigidly selected for fecundity, with predominant tumour types being pulmonary, lymphoreticular, and mammary, while renal and cardiovascular disease was common in the elderly and males outlived females.

A Multiple Comparison Procedure for Comparing Several Treatments with a Control

(1955). A Multiple Comparison Procedure for Comparing Several Treatments with a Control. Journal of the American Statistical Association: Vol. 50, No. 272, pp. 1096-1121.

Robust tests for equality of variances