Subchronic exposure to a glyphosate-based herbicide causes dysplasia in the digestive tract of Wistar rats.

Glyphosate-based herbicides (GBH) are the most widely used herbicide for treatment of crops in the world. The digestive tract is one of the first systems exposed to pesticides, and damage to this system can affect the general health of individuals. The aim of this study was to evaluate the effects of subchronic inhalation and oral exposure to GBH on the digestive tract in rats. Six groups of Wistar rats (male and female) were exposed to nebulization with three concentrations of GBH [3.71 × 10-3 grams of active ingredient per hectare (g.a.i./ha), 6.19 × 10-3 g.a.i./ha and 9.28 × 10-3 g.a.i./ha] administered orally or by inhalation for 75 days. Bone marrow cells, smears of the tongue and fragments of the tongue, oesophagus, stomach and intestine were collected for histopathological analysis. Congestion, inflammation, an increase in the number of mast cells and nucleoli-organizing regions were detected in the tongue in the groups exposed to GBH. Females had a higher number of mast cells in the tongue than males. Animals in the groups exposed to higher concentrations of GBH showed dysplasia in the oesophagus and small and large intestine regardless of sex. Gastric changes were not observed. Animals exposed to GBH showed increased micronucleus formation. Our data indicate that GBH causes oral allergies and dysplastic lesions in the oesophagus and small and large intestine and has genotoxic potential.

Cardiovascular damage associated with subchronic exposure to the glyphosate herbicide in Wistar rats.

Glyphosate is the most widely used herbicide in the world. Although some studies have shown cardiac electrophysiological changes associated to glyphosate, the histopathological changes that this herbicide may cause in the cardiovascular system are not yet established. The aim of this study was to evaluate the cardiovascular effects of subchronic oral and inhalation exposure to the glyphosate herbicide in rats. Eighty albino Wistar rats were distributed into eight groups (five males and five females/group): inhalation control: nebulization with sodium chloride solution (NaCl); oral control: nebulized feed with NaCl; low inhalation concentration: nebulization with 3.71 × 10-3 grams of active ingredient per hectare (g.a.i./ha) of glyphosate; low oral concentration: nebulized feed with 3.71 × 10-3 g.a.i./ha of glyphosate; medium inhalation concentration: nebulization with 6.19 × 10-3 g.a.i./ha of glyphosate; medium oral concentration: nebulized feed with 6.19 × 10-3 g.a.i./ha of glyphosate; high inhalation concentration: nebulization with 9.28 × 10-3 g.a.i./ha of glyphosate; and high oral concentration: nebulized feed with 9.28 × 10-3 g.a.i./ha of glyphosate. After 75 days of exposure, the animals were euthanized, and aortas and hearts were collected for histopathological analysis. Fatty streaks were observed in most animals exposed to glyphosate and were more prevalent in male rats, regardless of the route of exposure (p < 0.05). There were no differences in the measurements of the thickness of the right and left ventricle or in the collagen density of both ventricles in any of the groups evaluated (p > 0.05). Our study suggests that glyphosate has atherogenic potential, regardless of the concentration and route of exposure.

Protective effects of Bidens pilosa on hepatoxicity and nephrotoxicity induced by carbon tetrachloride in rats.

The aim of this study was to assess the protective effects of oral and topical treatment with Bidens pilosa (BP) against carbon tetrachloride (CCl4)- induced toxicity. Fifty-six rats were divided into seven groups: A: CCl4 only; B: CCl4+oral BP; C: CCl4 and topical BP; D: CCl4+oral and topical BP; E: oral BP only; F: negative control; and G: positive control (cyclophosphamide). The animals were treated for 10 weeks. Blood samples were collected for tests of hepatic and renal function, and fragments of the liver, spleen, pancreas, kidney, and intestine were collected for histopathological analyses. Cells from the femoral bone marrow were used for a micronucleus test and 'comet assay'. Statistically significant differences were observed in the levels of gamma-glutamyl transpeptidase (GGT), albumin, urea and creatinine, hepatic inflammation, renal tubular lesion, and inflammation of the intestinal mucosa between the BP-treated groups and untreated group. The median number of micronuclei in group A was 4.00, in group G was 9.00 and in the other groups was 0.00. Group A had the lowest number of cells with a score of 0 and the greatest number with scores of 3 and 4, similar to the results obtained from group G using the 'comet assay'. Thus, BP effectively protected against the toxic effects of CCl4 on the liver, kidney, and intestine and exerted an antimutagenic effect on rats exposed to CCl4.