Table 1.
Summary of the thyroid toxic effects after glyphosate or glyphosate-based herbicides (GBH) exposure in amphibians.
| Chemical | LOAEL for the study | Experimental model | Age at beginning of exposure | Exposure duration | Exposure route | Main results | Reference |
|---|---|---|---|---|---|---|---|
| GBH (containing or not POEA), Glyphosate, or POEA surfactant |
6 mg/L | Tadpoles | Gosner stages (GS) 20 and 25 | 24 and 96 h | Water (aquaria) | In GBH containing POEA and POEA: ↑ Tail damage ↓ Tail length ↑ expression Thrb in tail |
Howe et al. (83) |
| GBH (Roundup WeatherMax and Vision, Monsanto Co.) |
0.21 mg/L | Tadpoles | GS 25 | two pulses (4 consecutive days) within 2 weeks | Water (aquaria) | ↓ expression Thrb in brain | Lanctôt et al. (87) |
| GBH (VisionMax, Monsanto Co.) | 0.21 mg/L | Tadpoles | GS 25 | 41 days | Water (aquaria) | ↑ expression Dio2 and Dio3 in brain Delayed metamorphosis |
Navarro-Martín et al. (88) |
| GBH IPA (Aquamaster, Monsanto Co.), or GHB IPA+ Agri-dex surfactant, or GHB IPA+ Competitor surfactant | GHB IPA+ Competitor surfactant: 711 mg/L | Tadpoles | GS 35 to 38 | 24 and 48h | Water (aquaria) | Both herbicide mixes were more toxic than the active ingredient alone ↑Tadpole mortality in the herbicide mixture |
Vincent and Davidson (89) |
| GBH (Roundup ULTRA MAX®, Monsanto Co.) or technical-grade glyphosate |
GHB: 0.0007 mg/L GLY: 15 mg/L |
Tadpoles | GS 25 and 36 | 96 h | Water (aquaria) |
GBH Swimming activity was affected Effects on growth, development, and abnormalities GLY Effects on growth, development, and abnormalities |
Bach et al. (90) |
| GBH (Roundup Original®, Monsanto) | 18 μgl−1 | Tadpoles | GS 25 | 7 days | Water (aquaria) | ↓ Glycogen ↑ Total lipid levels ↓ Triglyceride levels ↑ Cholesterol levels ↓ Total protein ↑ LPO ↓ Glycogen, cholesterol, total protein and triglyceride levels in the liver ↓ Glycogen, Total lipid, Triglyceride in the tissue muscle ↑Total protein in the muscle ↑ Lipid peroxidation levels in the Gills, liver and tissue muscle ↑Weight and size |
Dornelles and Oliveira (91) |
| GBH (Glyphogan®Classic, Monsanto Co.) | 2 mg a.e/L | Tadpoles | GS 25 | 1st, 2nd, 3rd, 4th, or 5th period of their larval development, each period lasting 9 days. Or even throughout the experiment period (5th period larval) |
Water (aquaria) | ↓ Body mass at metamorphosis during the entire experiment ↑ Time to metamorphosis during the entire experiment Slow development of tadpoles exposed throughout the experimental period Low dose individuals in the first exposure period group developed slower High dose ↓ Body mass in the 1st, 4th, and 5th period Individuals in the 1st,2nd, 3rd, 4th exposure period group developed slower |
Mikó et al. (92) |
| GBH (Roundup1UltraMax and Focus Ultra, Monsanto Co.) | 13.5 mg/L | Tadpoles | GS 25 | 96 h | Water (aquaria) | Delayed metamorphosis | Wagner et al. (93) |
| GBH (Roundup original®DI) | 144 µg/L | Tadpoles | GS 25–26 | acute assay: 96 h chronic assay: 14 days |
Water (aquaria) | Tadpoles showed shorter lengths and lower masses ↑ Malformation in the mouth, the epithelium color and bowel edema |
Herek et al. (94) |
| GBH (Roundup® Star) or Glyphosate (PESTANAL®, analytic grade, 45521, Sigma-Aldrich) | –Stage 8: 37.8 mg active ingredient L−1 for embryos –Stage 46: 45.1 mg active ingredient L−1 for tadpoles |
Embryos and tadpoles | –FETAX test: stage 8 embryos –Tadpole-toxicity bioassays: stage 46 |
24, 48, 72 and 96 h | Water/in a standard Frog Embryo Teratogenesis Assay Xenopus (FETAX) test medium | GBH: Significant inhibition of embryonic growth ↓Activity of GR, CaE, AChE, and SOD |
Turhan et al. (95) |