Glyphosate effects on earthworms

This is a list of papers on glyphosate effects on earthworms. The list doesn’t contain all papers on the subject and might occasionally be updated.

Harmful effects

Effects of different concentrations of glyphosate (Roundup 360®) on earthworms (Octodrilus complanatus, Lumbricus terrestris and Aporrectodea caliginosa) in vineyards in the North-East of Italy (Stellin et al. 2018)
“Earthworms in untreated terraria were found all alive, while specimens exposed to glyphosate (Roundup 360®) showed a decreasing survival rate and a sharp decline in the number of cocoons.” … “Results indicate the occurrence of some resistance mechanisms on anecic earthworms in vineyards that have been exposed to glyphosate for at least three decades. However in spite of the long period of application of glyphosate the impact of this largely applied herbicide is still serious (up to 26% of mortality) especially on the deep-burrowing earthworms species (Oc. complanatus and L. terrestris).”

Effects of herbicides, glyphosate, on density and casting activity of earthworm, Pheretima (Amynthas) carnosus (Kaneda et al. 2016)
“From these results, the herbicide did not have direct harmful impacts on the earthworm, but would effect on earthworm casting activity through variation of environmental factors, such as litter amount, soil temperature, and soil moisture.”

Toxicity of AMPA to the earthworm Eisenia andrei Bouché, 1972 in tropical artificial soil (Domínguez et al. 2016)
“Our results suggest that earthworms coming from parents grown in contaminated soils may have reduced growth, limiting their beneficial roles in key soil ecosystem functions.” (AMPA = Aminomethylphosphonic acid – one of glyphosate’s main metabolites.)

Survival, Reproduction, Avoidance Behavior and Oxidative Stress Biomarkers in the Earthworm Octolasion cyaneum Exposed to Glyphosate (Salvio et al. 2016)
“These results indicate that environmentally relevant concentrations of GLY (up to 996 µg GLY kg-1 dry soil) did not exert a toxic effect to O. cyaneum.”

Glyphosate-based herbicides reduce the activity and reproduction of earthworms and lead to increased soil nutrient concentrations (Gaupp-Berghausen et al. 2015)
“We demonstrate, that the surface casting activity of vertically burrowing earthworms (Lumbricus terrestris) almost ceased three weeks after herbicide application, while the activity of soil dwelling earthworms (Aporrectodea caliginosa) was not affected. Reproduction of the soil dwellers was reduced by 56% within three months after herbicide application. Herbicide application led to increased soil concentrations of nitrate by 1592% and phosphate by 127%, pointing to potential risks for nutrient leaching into streams, lakes, or groundwater aquifers.”

Glyphosate Sublethal Effects on the Population Dynamics of the Earthworm Eisenia fetida (Savigny, 1826) (Santadino et al. 2014)
“The matrix population model built showed that while the control population had a positive growth rate, both glyphosate treatments showed negative growth rates. The results suggest that under these sublethal effects, non-target populations are at risk of local extinction, underscoring the importance of this type of studies in agrochemical environmental risk assessment.”

Glyphosate herbicide affects belowground interactions between earthworms and symbiotic mycorrhizal fungi in a model ecosystem (Zaller et al. 2014)
“We found that herbicides significantly decreased root mycorrhization, soil AMF spore biomass, vesicles and propagules. Herbicide application and earthworms increased soil hyphal biomass and tended to reduce soil water infiltration after a simulated heavy rainfall. Herbicide application in interaction with AMF led to slightly heavier but less active earthworms. Leaching of glyphosate after a simulated rainfall was substantial and altered by earthworms and AMF.”

Earthworm communities and soil properties in shaded coffee plantations with and without application of glyphosate (García-Pérez et al. 2014)
“Our findings indicated reduced species number, density and biomass of earthworms, and increased net carbon mineralization rate in plots with GBH.”

Exposure Assessment to Glyphosate of Two Species of Annelids (García-Torres et al. 2014)
“O. tyrtaeum was more sensitive to the highest concentration of glyphosate (50,000 mg kg-1), with 100 % mortality by day 7 of exposure, compared with 71 % for E. fetida. Although biomass of O. tyrtaeum was significantly different between the control and 5,000 mg kg-1 dose at day 14, E. fetida was not affected at that concentration, and only showed a significant weight loss after 7 days of exposure to 50,000 mg kg-1. Adverse effects upon adult fecundity and cocoon viability were observed at glyphosate concentrations of 5,000 mg kg-1 and above. Adverse effects were observed at concentrations that greatly exceeded the recommended field application rates of glyphosate.”

Genotoxic effects of glyphosate or paraquat on earthworm coelomocytes (Muangphra et al. 2014)
“This study showed that, at concentrations well below field application rates, paraquat induces both clastogenic and aneugenic effects on earthworm coelomocytes whereas glyphosate causes only aneugenic effects and therefore does not pose a risk of gene mutation in this earthworm.”

Comparative toxicity of two glyphosate-based formulations to Eisenia andrei under laboratory conditions (Piola et al. 2013)
“Median lethal concentration (LC50) showed that glyphosate-A was 4.5-fold more toxic than glyphosate-B. Sublethal concentrations caused a concentration-dependent weight loss, consistent with the reported effect of glyphosate as uncoupler of oxidative phosphorylation. Glyphosate-A showed deleterious effects on DNA and lysosomal damage at concentrations close to the applied environmental concentrations (14.4µg ae cm-2).”

Toxicity of three pesticides commonly used in Brazil to Pontoscolex corethrurus (Müller, 1857) and Eisenia andrei (Bouché, 1972) (Buch et al. 2013)
“Glyphosate showed no toxic effects for either species even at the highest concentration tested (47mga.i.kg-1), although they displayed avoidance behavior at this concentration.”

Toxicity assessment of 45 pesticides to the epigeic earthworm Eisenia fetida (Wang et al. 2012)

Effects of Glyphosate and 2,4-D on Earthworms (Eisenia foetida) in Laboratory Tests (Correia & Moreira, 2010)
“Earthworms kept in glyphosate-treated soil were classified as alive in all evaluations, but showed gradual and significant reduction in mean weight (50%) at all test concentrations. For 2,4-D, 100% mortality was observed in soil treated with 500 and 1,000 mg/kg. At 14 days, 30%–40% mortality levels were observed in all other concentrations. No cocoons or juveniles were found in soil treated with either herbicide. Glyphosate and 2,4-D demonstrated severe effects on the development and reproduction of Eisenia foetida in laboratory tests in the range of test concentrations.”

Effect of Pesticides on the Reproductive Output of Eisenia fetida (Yasmin & D’Souza, 2007)
“The results showed that the pesticide treatment had a marked negative impact on the growth and reproduction of earthworms. Carbendazim and dimethoate were found to cause greater harm to the selected earthworm species than glyphosate.”

Ecotoxicological assessment of the effects of glyphosate and chlorpyrifos in an Argentine soya field (Casabé et al. 2007)
“GLY reduced cocoon viability, decreasing the number of juveniles. Moreover, earthworms avoided soils treated with GLY.” … “Both pesticides caused a reduction in the feeding activity under laboratory and field conditions.”

As the Worm Turns: Eisenia fetida Avoids Soil Contaminated by a Glyphosate-Based Herbicide (Verrell & Van Buskirk, 2004)

Histochemical and histopathological study of the intestine of the earthworm (Pheretima elongata) exposed to a field dose of the herbicide glyphosate (Morowati, 2000)
“These results suggest that glyphosate, even at the recommended field dose, could cause cell death and interfere with non-specific esterases activity of the epithelial lining of the intestine of P. elongata causing at least 50 percent mortality in the population of the worms.”

Glyphosate, 2,4-DB and dimethoate: Effects on earthworm survival and growth (Dalby et al. 1995)

Effect of repeated low doses of biocides on the earthworm Aporrectodea caliginosa in laboratory culture (Springett & Gray, 1992)
“Azinphos-methyl and Glyphosate applied alone, reduced growth the most over the 100 days and at all rates of application.”

Beneficial effects

Inhibition effect of glyphosate on the acute and subacute toxicity of cadmium to earthworm Eisenia fetida (Zhou et al. 2014)
The presence of glyphosate reduced the concentration of Cd in all fractions, especially the intact cells. During a longer period of exposure, the weight loss of earthworm and the total Cd absorption was alleviated by glyphosate.

Subacute toxicity of copper and glyphosate and their interaction to earthworm (Eisenia fetida) (Zhou et al. 2013)
The joint toxicity data showed that the relative weight loss and the uptake of Cu, as well as the superoxide dismutase, catalase and malondialdehyde activities, were significantly alleviated in the present of GPS, which indicated that GPS could reduce the toxicity and bioavailability of Cu in the soil because of its strong chelating effects.

Does glyphosate impact on Cu uptake by, and toxicity to, the earthworm Eisenia fetida? (Zhou et al. 2012)
The mortality rates and whole-worm metal burdens increased significantly with the increasing Cu concentration in solution. However, toxicity of GPS to earthworms was not observed in this study. Furthermore, the presence of GPS could significantly reduce the acute toxicity of Cu to earthworms. The mortality rates decreased sharply and the uptake of Cu was nearly halted in the presence of GPS.