Bibliography Tag: glyphosate

Benbrook and Benbrook, 2021

Benbrook, Charles, & Benbrook, Rachel (2021). “A minimum data set for tracking changes in pesticide use.” In R. Mesnage & J. Zaller (Eds.), Herbicides: Elsevier and RTI Press.

ABSTRACT:

A frequently asked but deceptively simple question often arises about pesticide use on a given farm or crop: Is pesticide use going up, down, or staying about the same? Where substantial changes in pesticide use are occurring, it is also important to understand the factors driving change. These might include more or fewer hectares planted, a change in the crop mix, a higher or lower percentage of hectares treated, or higher or lower rates of application and/or number of applications. Or, it might arise from a shift to other pesticides applied at a higher or lower rate and/or lessened or greater reliance on nonpesticidal strategies and integrated pest management (IPM). Questions about whether pesticide use is changing and why arise for a variety of reasons. Rising use typically increases farmer costs and cuts into profit margins. It generally raises the risk of adverse environmental and/or public health outcomes. It can accelerate the emergence and spread of organisms resistant to applied pesticides. If the need to spray more continues year after year for long enough, farming systems become unsustainable. Lessened reliance on and use of pesticides, on the other hand, are typically brought about and can only be sustained by incrementally more effective prevention-based biointensive IPM systems (bioIPM).1–3 Fewer pesticide applications and fewer pounds/kilograms of active ingredient applied reduce the impacts on nontarget organisms and provide space for beneficial organisms and biodiversity to flourish. Such systems reduce the odds of significant crop loss in years when conditions undermine the efficacy of control measures, leading to spikes in pest populations and the risk of economically meaningful loss of crop yield and/or quality. FULL TEXT


Milesi et al., 2021

Milesi, M. M., Lorenz, V., Durando, M., Rossetti, M. F., & Varayoud, J. “Glyphosate Herbicide: Reproductive Outcomes and Multigenerational Effects.” Frontiers in Endocrinology, 12. 2021; DOI:10.3389/fendo.2021.672532.

ABSTRACT:

Glyphosate base herbicides (GBHs) are the most widely applied pesticides in the world and are mainly used in association with GBH-tolerant crop varieties. Indiscriminate and negligent use of GBHs has promoted the emergence of glyphosate resistant weeds, and consequently the rise in the use of these herbicides. Glyphosate, the active ingredient of all GBHs, is combined with other chemicals known as co-formulants that enhance the herbicide action. Nowadays, the safety of glyphosate and its formulations remain to be a controversial issue, as evidence is not conclusive whether the adverse effects are caused by GBH or glyphosate, and little is known about the contribution of co-formulants to the toxicity of herbicides. Currently, alarmingly increased levels of glyphosate have been detected in different environmental matrixes and in foodstuff, becoming an issue of social concern. Some in vitro and in vivo studies have shown that glyphosate and its formulations exhibit estrogen-like properties, and growing evidence has indicated they may disrupt normal endocrine function, with adverse consequences for reproductive health. Moreover, multigenerational effects have been reported and epigenetic mechanisms have been proved to be involved in the alterations induced by the herbicide. In this review, we provide an overview of: i) the routes and levels of human exposure to GBHs, ii) the potential estrogenic effects of glyphosate and GBHs in cell culture and animal models, iii) their long-term effects on female fertility and mechanisms of action, and iv) the consequences on health of successive generations. FULL TEXT


Mesnage et al., 2021C

Mesnage R, Mazzacuva F, Caldwell A, Halket J, Antoniou MN. “Urinary excretion of herbicide co-formulants after oral exposure to roundup MON 52276 in rats.” Environmental Research. 2021 Jun;197:111103. DOI: 10.1016/j.envres.2021.111103.

ABSTRACT:

The toxicity of surfactants, which are an integral component of glyphosate-formulated products is an underexplored and highly debated subject. Since biomonitoring human exposure to glyphosate co-formulants is considered as a public health priority, we developed and validated a high-resolution mass spectrometry method to measure the urinary excretion of surfactants present in Roundup MON 52276, the European Union (EU) representative formulation of glyphosate-based herbicides. Quantification was performed measuring the 5 most abundant compounds in the mixture. We validated the method and showed that it is highly accurate, precise and reproducible with a limit of detection of 0.0004 μg/mL. We used this method to estimate the oral absorption of MON 52276 surfactants in Sprague-Dawley rats exposed to three concentrations of MON 52276 via drinking water for 90 days. MON 52276 surfactants were readily detected in urine of rats administered with this commercial Roundup formulation starting from a low concentration corresponding to the EU glyphosate acceptable daily intake. Our results provide a first step towards the implementation of surfactant co-formulant biomonitoring in human populations. FULL TEXT


Silver et al., 2021

Silver, M. K., Fernandez, J., Tang, J., McDade, A., Sabino, J., Rosario, Z., Velez Vega, C., Alshawabkeh, A., Cordero, J. F., & Meeker, J. D.; “Prenatal Exposure to Glyphosate and Its Environmental Degradate, Aminomethylphosphonic Acid (AMPA), and Preterm Birth: A Nested Case-Control Study in the PROTECT Cohort (Puerto Rico);” Environmental Health Perspectives, 2021, 129(5), 57011; DOI: 10.1289/EHP7295.

ABSTRACT:

BACKGROUND: Glyphosate (GLY) is the most heavily used herbicide in the world. Despite nearly ubiquitous exposure, few studies have examined prenatal GLY exposure and potentially adverse pregnancy outcomes. Preterm birth (PTB) is a risk factor for neonatal mortality and adverse health effects in childhood.

OBJECTIVES: We examined prenatal exposure to GLY and a highly persistent environmental degradate of GLY, aminomethylphosphonic acid (AMPA), and odds of PTB in a nested case-control study within the ongoing Puerto Rico Testsite for Exploring Contamination Threats (PROTECT) pregnancy cohort in northern Puerto Rico.

METHODS: GLY and AMPA in urine samples collected at 18+/-2 (Visit 1) and 26+/-2 (Visit 3) wk gestation (53 cases/194 randomly selected controls) were measured using gas chromatography tandem mass spectrometry. Multivariable logistic regression was used to estimate associations with PTB (delivery <37wk completed gestation).

RESULTS: Detection rates in controls were 77.4% and 77.5% for GLY and 52.8% and 47.7% for AMPA, and geometric means (geometric standard deviations) were 0.44 (2.50) and 0.41 (2.56) mug/L for GLY and 0.25 (3.06) and 0.20 (2.87) mug/L for AMPA, for Visits 1 and 3, respectively. PTB was significantly associated with specific gravity-corrected urinary GLY and AMPA at Visit 3, whereas associations with levels at Visit 1 and the Visits 1-3 average were largely null or inconsistent. Adjusted odds ratios (ORs) for an interquartile range increase in exposure at Visit 3 were 1.35 (95% CI: 0.99, 1.83) and 1.67 (95% CI: 1.26, 2.20) for GLY and AMPA, respectively. ORs for Visit 1 and the visit average were closer to the null.

DISCUSSION: Urine GLY and AMPA levels in samples collected near the 26th week of pregnancy were associated with increased odds of PTB in this modestly sized nested case-control study. Given the widespread use of GLY, multiple potential sources of AMPA, and AMPA’s persistence in the environment, as well as the potential for long-term adverse health effects in preterm infants, further investigation in other populations is warranted.

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Kogevinas, 2021

Kogevinas, M.; “Glyphosate Exposure during Pregnancy and Preterm Birth (More Research Is Needed);” Environmental Health Perspectives, 2021, 129(5), 51301; DOI: 10.1289/EHP9428.

ABSTRACT:

Not Available

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Ganesan and Keating, 2020

Ganesan, S., & Keating, A. F.; “Ovarian mitochondrial and oxidative stress proteins are altered by glyphosate exposure in mice;” Toxicology and Applied Pharmacology, 2020, 402, 115116; DOI: 10.1016/j.taap.2020.115116.

ABSTRACT:

Glyphosate (GLY) usage for weed control is extensive. To investigate ovarian impacts of chronic GLY exposure, female C57BL6 mice were orally administered saline as vehicle control (CT) or GLY at 0.25 (G0.25), 0.5 (G0.5), 1.0 (G1.0), 1.5 (G1.5), or 2 (G2.0) mg/kg for five days per wk. for 20 wks. Feed intake increased (P < .05) in G1.5 and G2.0 mice and body weight increased (P < .05) in G1.0 mice. There was no impact of GLY on estrous cyclicity, nor did GLY affect circulating levels of 17beta-estradiol or progesterone. Exposure to GLY did not impact heart, liver, spleen, kidney or uterus weight. Both ovarian weight and follicle number were increased (P < .05) by G2.0 but not affected at lower GLY concentrations. There were no detectable effects of GLY on ovarian protein abundance of pAKT, AKT, pAKT:AKT, gammaH2AX, STAR, CYP11A1, HSD3B, CYP19A, ERA or ERB. Increased (P < .05) abundance of ATM protein was observed at G0.25 but not higher GLY doses. A dose-dependent effect (P < .10) of GLY exposure on ovarian protein abundance as quantified by LC-MS/MS was observed (G0.25-4 increased, 19 decreased; G0.5-5 increased, 25 decreased; G1.0-65 increased, 7 decreased; G1.5-145 increased, 2 decreased; G2.0-159 increased, 4 decreased). Pathway analysis was performed using DAVID and identified glutathione metabolism, metabolic and proteasome pathways as GLY exposure targets. These data indicate that chronic low-level exposure to GLY alters the ovarian proteome and may ultimately impact ovarian function. FULL TEXT


Franke et al., 2021

Franke, Adrian A., Li, Xingnan, Shvetsov, Yurii B., & Lai, Jennifer F.; “Pilot study on the urinary excretion of the glyphosate metabolite aminomethylphosphonic acid and breast cancer risk: The Multiethnic Cohort study;” Environmental Pollution, 2021, 277, 116848; DOI: https://doi.org/10.1016/j.envpol.2021.116848.

ABSTRACT:

Breast cancer is the most commonly diagnosed female cancer and the second leading cause of death in women in the US, including Hawaii. Accumulating evidence suggests that aminomethylphosphonic acid (AMPA), the primary metabolite of the herbicide glyphosate—a probable human carcinogen, may itself be carcinogenic. However, the relationship between urinary AMPA excretion and breast cancer risk in women is unknown. In this pilot study, we investigated the association between pre-diagnostic urinary AMPA excretion and breast cancer risk in a case-control study of 250 predominantly postmenopausal women: 124 cases and 126 healthy controls (individually matched on age, race/ethnicity, urine type, date of urine collection, and fasting status) nested within the Hawaii biospecimen subcohort of the Multiethnic Cohort. AMPA was detected in 90% of cases and 84% of controls. The geometric mean of urinary AMPA excretion was nearly 38% higher among cases vs. controls (0.087 vs 0.063 ng AMPA/mg creatinine) after adjusting for race/ethnicity, age and BMI. A 4.5-fold higher risk of developing breast cancer in the highest vs. lowest quintile of AMPA excretion was observed (ORQ5 vs. Q1: 4.49; 95% CI: 1.46–13.77; ptrend = 0.029). To our knowledge, this is the first study to prospectively examine associations between urinary AMPA excretion and breast cancer risk. Our preliminary findings suggest that AMPA exposure may be associated with increased breast cancer risk; however, these results require confirmation in a larger population to increase study power and permit careful examinations of race/ethnicity differences.


Coullery et al., 2020

Coullery, R., Pacchioni, A. M., & Rosso, S. B.; “Exposure to glyphosate during pregnancy induces neurobehavioral alterations and downregulation of Wnt5a-CaMKII pathway;” Reproductive Toxicology, 2020, 96, 390-398; DOI: 10.1016/j.reprotox.2020.08.006.

ABSTRACT:

Glyphosate-based formulations are the most popular herbicide used around the world. These herbicides are widely applied in agriculture to control weeds on genetically modified crops. Although there is much evidence showing that glyphosate-based herbicides induce toxic effect on reproductive and hepatic systems, and also cause oxidative damage on cells, studies from recent years revealed that the nervous system may represent a key target for their toxicity. In the present work, we evaluated the effect of glyphosate (without adjuvants) in neonate rats after gestational exposure. Particularly, we examined whether glyphosate during gestation affected the nervous system function at early development. Pregnant Wistar rats were treated with 24 or 35mg/kg of pure glyphosate every 48h and neurobehavioral studies were performed. Our results indicated that gestational exposure to glyphosate induced changes in reflexes development, motor activity and cognitive function, in a dose-dependent manner. To go further, we evaluated whether prenatal exposure to glyphosate affected the Ca(+2)-mediated Wnt non-canonical signaling pathway. Results indicated that embryos exposed to glyphosate showed an inhibition of Wnt5a-CaMKII signaling pathway, an essential cascade controlling the formation and integration of neural circuits. Taken together, these findings suggest that gestational exposure to glyphosate leads to a downregulation of Wnt/Ca(+2) pathway that could induce a developmental neurotoxicity evidenced by deficits at behavioral and cognitive levels in rat pups. FULL TEXT


Mesnage et al., 2021B

Mesnage, R., Teixeira, M., Mandrioli, D., Falcioni, L., Ibragim, M., Ducarmon, Q. R., Zwittink, R. D., Amiel, C., Panoff, J. M., Bourne, E., Savage, E., Mein, C. A., Belpoggi, F., & Antoniou, M. N.; “Multi-omics phenotyping of the gut-liver axis reveals metabolic perturbations from a low-dose pesticide mixture in rats;” Communications Biology, 2021, 4(1), 471; DOI: 10.1038/s42003-021-01990-w.

ABSTRACT:

Health effects of pesticides are not always accurately detected using the current battery of regulatory toxicity tests. We compared standard histopathology and serum biochemistry measures and multi-omics analyses in a subchronic toxicity test of a mixture of six pesticides frequently detected in foodstuffs (azoxystrobin, boscalid, chlorpyrifos, glyphosate, imidacloprid and thiabendazole) in Sprague-Dawley rats. Analysis of water and feed consumption, body weight, histopathology and serum biochemistry showed little effect. Contrastingly, serum and caecum metabolomics revealed that nicotinamide and tryptophan metabolism were affected, which suggested activation of an oxidative stress response. This was not reflected by gut microbial community composition changes evaluated by shotgun metagenomics. Transcriptomics of the liver showed that 257 genes had their expression changed. Gene functions affected included the regulation of response to steroid hormones and the activation of stress response pathways. Genome-wide DNA methylation analysis of the same liver samples showed that 4,255 CpG sites were differentially methylated. Overall, we demonstrated that in-depth molecular profiling in laboratory animals exposed to low concentrations of pesticides allows the detection of metabolic perturbations that would remain undetected by standard regulatory biochemical measures and which could thus improve the predictability of health risks from exposure to chemical pollutants. FULL TEXT


Gorga et al., 2021

Gorga, A., Rindone, G. M., Centola, C. L., Sobarzo, C. M., Pellizzari, E. H., Camberos, M. D. C., Marin-Briggiler, C. I., Cohen, D. J., Riera, M. F., Galardo, M. N., & Meroni, S. B.; “Low Doses of Glyphosate/Roundup Alter Blood-Testis Barrier Integrity in Juvenile Rats;” Frontiers in Endocrinology, 2021, 12, 615678; DOI: 10.3389/fendo.2021.615678.

ABSTRACT:

It has been postulated that glyphosate (G) or its commercial formulation Roundup (R) might lead to male fertility impairment. In this study, we investigated the possible effects of G or R treatment of juvenile male rats on blood-testis barrier function and on adult male sperm production. Pups were randomly assigned to the following groups: control group (C), receiving water; G2 and G50 groups, receiving 2 and 50 mg/kg/day G respectively; and R2 and R50 groups receiving 2 and 50 mg/kg/day R respectively. Treatments were performed orally from postnatal day (PND) 14 to 30, period of life that is essential to complete a functional blood-testis barrier. Evaluation was done on PND 31. No differences in body and testis weight were observed between groups. Testis histological analysis showed disorganized seminiferous epithelium, with apparent low cellular adhesion in treated animals. Blood-testis barrier permeability to a biotin tracer was examined. A significant increase in permeable tubules was observed in treated groups. To evaluate possible mechanisms that could explain the effects on blood-testis barrier permeability, intratesticular testosterone levels, androgen receptor expression, thiobarbituric acid reactive substances (TBARS) and the expression of intercellular junction proteins (claudin11, occludin, ZO-1, connexin43, 46, and 50 which are components of the blood-testis barrier) were examined. No modifications in the above-mentioned parameters were detected. To evaluate whether juvenile exposure to G and R could have consequences during adulthood, a set of animals of the R50 group was allowed to grow up until PND 90. Histological analysis showed that control and R50 groups had normal cellular associations and complete spermatogenesis. Also, blood-testis barrier function was recovered and testicular weight, daily sperm production, and epididymal sperm motility and morphology did not seem to be modified by juvenile treatment. In conclusion, the results presented herein show that continuous exposure to low doses of G or R alters blood-testis barrier permeability in juvenile rats. However, considering that adult animals treated during the juvenile stage showed no differences in daily sperm production compared with control animals, it is feasible to think that blood-testis barrier impairment is a reversible phenomenon. More studies are needed to determine possible damage in the reproductive function of human juvenile populations exposed to low doses of G or R. FULL TEXT