IJCS | Volume 32, Nº2, May/June 2019

251 1. Brasil. Ministério da Saúde, Secretaria de Vigilância Sanitária, Departamento Técnico-Normativo, Divisão deMeioAmbiente e Ecologia Humana. Manual de vigilância da saúde de populações expostas a agrotóxicos. Brasilia;1997. P.57-69. 2. Song Y. Insight into the mode of action of 2,4-Dichlorophenoxyaceticacid (2,4-D) as an herbicide. J Integr Plant Biol. 2014;56(2):106-13. 3. Brasil. Presidência da República, Subchefia para Assuntos Jurídicos. Lei No. 7.802 de 11 de julho de 1989. Dispõe sobre a pesquisa, a References Negrão et al. Effect of herbicide 2,4D inhalation on cardiac remodeling Int J Cardiovasc Sci. 2019;32(3)247-252 Original Article In another study, Razavi 26 shows that exposure to Diazinon (DZN) through a catheter once a day, during a 4-week period, also resulted in cardiac lesions in rats and cardiac hypertrophy in the DZNgroup, showing that this exposure chronically induces infiltration of inflammatory cells and necrosis in cardiac tissue, where they play an important role in cardiotoxicity. The analysis of the fractal dimension did not demonstrate a significant increase in the animals exposed to the 2,4D herbicide in the HCG (n = 5) when compared to the CG animals (n = 5), suggesting that there was no cardiotoxicity when it evaluated by the fractal dimension method. This method reveals the irregularities in the histological slides, and the increase in the inflammatory process and the collagen can cause these alterations, as it occurs in cardiac remodeling. 29,30 Possibly, these changes did not occur in the short term. Further studies involving the inhalation route and chronic exposure might disclose these alterations. This study becomes extremely relevant from the clinical point-of-view, as it demonstrates the acute potential for short-term cardiac damage when herbicides are inhaled. Considering that the workload of rural workers exceeds this period, it is important to use personal protective equipment (PPE), and this information must be disclosed to farmers, alerting them to the risks of heart disease. 30,32 As a study limitation, we can cite sample size, with only 5 animals per group. The results of this study, which is a translational research, show the possible heart damage that can be caused by pesticide exposure in the body of rural workers during their work routine. The pesticides can result in damage to the cardiac function and thus cause signs and symptoms of intolerance to exertion, such as fatigue and dyspnea. Control strategies to prevent the inhalation of these substances by rural workers are necessary to prevent progression to pathological cardiac remodeling. 8 Moreover, further analyses may also be used to characterize other pathological cardiac alterations, such as molecular analyses of the heart and evaluations of systolic and diastolic functions by echocardiography. The mechanisms involved in cardiac hypertrophy should also be elucidated. 33 Conclusion The 2,4D herbicide at acutely inhaled concentrations promoted cardiomyocyte hypertrophy in mice, showing its potential in causing pathological cardiac remodeling. Author contributions Conception and design of the research: Pacagnelli FL, Mariano TB, Sabela AKDA, Silva RCR, Nai GA. Acquisition of data: Negrão ALR, Oliveira B, Gonçalves MG, Oliveira TFS. Analysis and interpretation of the data: Negrão ALR, Oliveira B, Gonçalves MG. Statistical analysis: Mantovani RO. Obtaining financing: Pacagnelli FL. Writing of the manuscript: Pacagnelli FL, Negrão ALR, Oliveira B, Gonçalves MG. Critical revision of the manuscript for intellectual content: Silva RCR, Nai GA. Supervision / as the major investigador: Pacagnelli FL. Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding There were no external funding sources for this study. Study Association This study is not associated with any thesis or dissertation work. Ethics approval and consent to participate This study was approved by the Ethics Committee on Animal Experiments of the University of Western São Paulo (UNOESTE) under the protocol number 3331.