Research Article Novel Acaricidal Drug Fluazuron Causes Immunotoxicity via Selective Depletion of Lymphocytes T CD8 Juliana Gonçalves Ribeiro, 1,2 Anelise Santos Soares, 2 Pamella Eduardha Espindola Chaves, 2 Jéssica Tamara Limberger, 2 Emanoeli da Rosa, 1,2 Lu-sa Zuravski, 2 Lu-s Flávio Souza de Oliveira, 1,2 and Michel Mansur Machado 1,2 1 Postgraduate Program in Pharmaceutical Sciences, Federal University of Pampa, BR 472, Km 585, Mailbox 118, CEP: 97500-970, Uruguaiana, RS, Brazil 2 TOXCEL-Cellular Toxicology Research Group, Federal University of Pampa, BR 472, Km 585, Mailbox 118, CEP: 97500-970, Uruguaiana, RS, Brazil Correspondence should be addressed to Michel Mansur Machado; michelmachado@unipampa.edu.br Received 29 January 2019; Accepted 22 April 2019; Published 7 May 2019 Academic Editor: Jairo Kennup Bastos Copyright © 2019 Juliana Gonc ¸alves Ribeiro et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Fluazuron is one of the newest veterinary antitick medicines. Belonging to the benzoylphenylureas group, its mechanism of action acts by the interference of the formation of the chitin of the tick, which is responsible for the hardening of its exoskeletons. In addition to taking care of the health of the animal so that it receives the medication in the doses and the correct form, it is important to analyze the safety of the operator. Reduced resistance to infectious disease was a well-documented consequence of primary and acquired immunodefciencies, but a novel fnding following xenobiotic exposure. Te awareness of the consequences of altered immune function is the most likely outcome of inadvertent exposure. Te human health implications of studies in which chemical exposure reduced resistance to infection drove an early focus on immunosuppression within the toxicology community. Te main objective is to perform the evaluation by computational platforms and in cell culture, searching for data that can serve as a foundation for a better understanding of the toxic efects involved with the accidental contamination of Fluazuron and, thus, to assist the medical community and users to understand the risks inherent in its use. As far as we can determine in the literature, our work has unmistakably demonstrated that the Fluazuron can cause genotoxicity by probable chromatin rearrangement and immunodepleting by specifc reduction of the CD8 T lymphocyte subpopulation, mediated by the decrease in gamma interferon production. Although the use of Fluazuron is a necessity for tick control and for cattle management, we must bear in mind that the imminent risks to its application exist. Careless use can damage the immune system which in turn carries a gigantic hazard by opening a door to diseases and pathogens and leaving us defenseless. 1. Introduction In recent years there have been several changes in beef cattle, with modern production applications, which allowed the sector to increase volume and productivity [1]. Due to the increase in animal production, there was a multiplication of the cases of parasitism, developing a wide range of para- sitic species, one among them being the tick Rhipicephalus (Boophilus) microplus [2]. One of the main control methods for the tick is the use of acaricides, the main ones being applied under immersion, spray, pour-on, and injectable formulations and the latter two being classifed as systemic action [3]. In the market there are several active principles and for- mulations. Fluazuron (N-[[4-chloro-3-[3-chloro-5-(trifuor- omethyl)pyridin-2-yl]oxyphenyl]carbamoyl]-2,6-difuorob- enzamide) (Figure 1) is one of the newest veterinary antitick medicines, which has the “pour-on” formula in which it means to apply the drug along the animal’s back [4]. Belonging to the benzoylphenylureas group, its mechanism of action acts by the interference of the formation of the chitin of the tick, which is responsible for the hardening Hindawi Evidence-Based Complementary and Alternative Medicine Volume 2019, Article ID 2815461, 7 pages https://doi.org/10.1155/2019/2815461