Programa de Pós-Graduação em Ciências da Saúde, Universidade do Oeste Paulista, Presidente Prudente, SP, Brasil.
Departamento de Medicina, Universidade do Oeste Paulista, Presidente Prudente, SP, Brasil.
Braz J Med Biol Res. 2022 Sep 12;55:e12350. doi: 10.1590/1414-431X2022e12350. eCollection 2022.
2,4-Dichlorophenoxyacetic acid (2,4-D) is a herbicide of the chlorophenoxy class and the second most widely used herbicide applied to several different crops worldwide. Environmental factors, especially those related to diet, strongly affect the risk of developing cancer of the gastrointestinal tract. There is currently no evidence to determine whether there is an association between 2,4-D exposure and gastrointestinal disorders. We evaluated the histological effect of chronic oral and inhalation exposure to 2,4-D on the digestive tract of rats. Eighty male adult albino Wistar rats were divided into 8 groups (n=10): two control groups, one for inhalation and one for oral exposure, and 6 groups exposed orally or by inhalation at three different concentrations of 2,4-D [3.71×10-3 grams of active ingredient per hectare (gai/ha), 6.19×10-3 gai/ha, and 9.28×10-3 gai/ha]. The animals were exposed for 6 months. The esophagus, stomach, and intestine were collected for histopathological analysis. Animals exposed to 2,4-D had hyperkeratosis of the esophagus, regardless of the exposure route. All animals exposed to a higher concentration of 2,4-D orally presented mild dysplasia of the large intestine. In the small intestine, most animals exposed to moderate and high concentrations of 2,4-D had mild dysplasia. No gastric changes were observed in any of the groups studied. Chronic exposure to 2,4-D, especially at moderate and high concentrations, regardless of the exposure route, caused reactive damage to the esophagus (hyperkeratosis) and dysplastic changes to the intestine.
2,4-二氯苯氧乙酸（2,4-D）是一种属于氯苯氧类的除草剂，也是全球应用于多种不同作物的第二大广泛使用的除草剂。环境因素，特别是与饮食有关的因素，强烈影响胃肠道癌症的发病风险。目前尚无证据确定 2,4-D 暴露与胃肠道疾病之间是否存在关联。我们评估了慢性口服和吸入 2,4-D 暴露对大鼠消化道的组织学影响。将 80 只雄性成年白化 Wistar 大鼠分为 8 组（n=10）：两组对照组，一组用于吸入，一组用于口服暴露，以及 6 组分别以三种不同浓度的 2,4-D [3.71×10-3 克有效成分/公顷（gai/ha）、6.19×10-3 gai/ha 和 9.28×10-3 gai/ha]经口或吸入暴露。动物暴露 6 个月。收集食管、胃和肠道进行组织病理学分析。暴露于 2,4-D 的动物食管均有过度角化，无论暴露途径如何。所有经口暴露于较高浓度 2,4-D 的动物均有大肠轻度发育不良。在小肠中，大多数经中等和高浓度 2,4-D 暴露的动物均有轻度发育不良。在研究的任何一组中均未观察到胃的变化。慢性暴露于 2,4-D，尤其是在中高浓度下，无论暴露途径如何，都会导致食管（过度角化）产生反应性损伤和肠道发育不良变化。
