Chronic inhalation exposure to the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) alters cardiac collagen in Wistar rats

Introduction: 2,4-dichlorophenoxyacetic acid (2,4-D) is one of the most used in the world and exposure to herbicides can affect animalsand humans, causing toxic effects that include cardiotoxicity. This is the first study to evaluate cardiac remodeling after experimentalsimulation of environmental exposure by chronic inhalation (6 months) to the herbicide 2,4-D. Methods: Thirty male Wistar rats were exposed to two different concentrations of the 2,4-D formulation (low - 187.17 mg/m3;andhigh - 467.93 mg/m3) and the control group exposed to nebulization of chloride solution 0.9% sodium. Inhalation exposure lasted6 months. Mice hearts were collected for histology. Results: There was a difference between exposure concentrations in relation to the increase in cardiac collagen (P<0.0001). In miceexposed to a low dose of 2,4-D and a decrease in the fractal dimension of cardiac collagen in the high dose of 2, 4-D (P=0.010).Discussion: This study shows that chronic inhalation exposure to 2,4-D induces cardiotoxicity in rats, characterized by extracellularmatrix reorganization and changes in collagen levels, highlighting the impact of the exposure route on cardiac outcomes. Conclusion: There was no difference in relation to anatomical parameters, cardiomyocyte area, collagen types I and III and analysis ofarteriole thickness. Chronic exposure at different doses to the 2,4D herbicide had the potential to cause damage to cardiac remodelingby altering cardiac collagen in rats.