Acquavella JF, Alexander BH, Mandel JS, Gustin C, Baker B, Chapman P, Bleeke M, “Glyphosate biomonitoring for farmers and their families: results from the Farm Family Exposure Study.” Environmental Health Perspectives, 2004, 112:3.
ABSTRACT: Glyphosate is the active ingredient in Roundup agricultural herbicides and other herbicide formulations that are widely used for agricultural, forestry, and residential weed control. As part of the Farm Family Exposure Study, we evaluated urinary glyphosate concentrations for 48 farmers, their spouses, and their 79 children (4-18 years of age). We evaluated 24-hr composite urine samples for each family member the day before, the day of, and for 3 days after a glyphosate application. Sixty percent of farmers had detectable levels of glyphosate in their urine on the day of application. The geometric mean (GM) concentration was 3 ppb, the maximum value was 233 ppb, and the highest estimated systemic dose was 0.004 mg/kg. Farmers who did not use rubber gloves had higher GM urinary concentrations than did other farmers (10 ppb vs. 2.0 ppb). For spouses, 4% had detectable levels in their urine on the day of application. Their maximum value was 3 ppb. For children, 12% had detectable glyphosate in their urine on the day of application, with a maximum concentration of 29 ppb. All but one of the children with detectable concentrations had helped with the application or were present during herbicide mixing, loading, or application. None of the systemic doses estimated in this study approached the U.S. Environmental Protection Agency reference dose for glyphosate of 2 mg/kg/day. Nonetheless, it is advisable to minimize exposure to pesticides, and this study did identify specific practices that could be modified to reduce the potential for exposure. FULL TEXT
Carlos Alvarez-Moya, Mónica Reynoso Silva, Carlos Valdez Ramírez, David Gómez Gallardo, Rafael León Sánchez, Alejandro Canales Aguirre, Alfredo Feria Velasco, “Comparison of the in vivo and in vitro genotoxicity of glyphosate isopropylamine salt in three different organisms,” Genetics and Molecular Biology, 2014, 37:1, DOI: 10.1590/S1415-47572014000100016
There is considerable controversy with regard to the genotoxicity of glyphosate, with some reports stating that this compound is non-toxic for fish, birds and mammals. In this work, we used the comet assay to examine the genotoxicity of glyphosate isopropylamine (0.7, 7, 70 and 700 µM) in human lymphocytes, erythrocytes of Oreochromis niloticus and staminal nuclei of Tradescantia (4430) in vitro and in vivo. Cells, nuclei and fish that had and had not been exposed to 5 mM N-nitrosodiethylamine (NDEA) were used as positive and negative controls, respectively. Significant (p < 0.01) genetic damage was observed in vivo and in vitro in all cell types and organisms tested. Human lymphocytes and Tradescantia hairs showed lower genetic damage in vivo compared to in vitro, possibly because of efficient metabolization of the herbicide. In O. niloticus erythrocytes, significant (p < 0.001) genotoxicity was observed at > 7 µM, whereas in vitro, glyphosphate was genotoxic in human lymphocytes and Tradescantia hairs at > 0.7 µM. These results indicate that glyphosate is genotoxic in the cells and organisms studied at concentrations of 0.7-7 µM. FULL TEXT
M Antoniou, MEM Habib, CV Howard, RC Jennings, C Leifert, RO Nodari, CJ Robinson and J Fagan, “Teratogenic Effects of Glyphosate-Based Herbicides: Divergence of Regulatory Decisions from Scientific Evidence,” Environmental and Analytical Toxicology, S:4, 2012, DOI: 10.4172/2161-0525.S4-006.
The publication of a study in 2010, showing that a glyphosate herbicide formulation and glyphosate alone caused malformations in the embryos of Xenopus laevis and chickens through disruption of the retinoic acid signalling pathway, caused scientific and regulatory controversy. Debate centred on the effects of the production and consumption of genetically modified Roundup Ready® soy, which is engineered to tolerate applications of glyphosate herbicide. The study, along with others indicating teratogenic and reproductive effects from glyphosate herbicide exposure, was rebutted by the German Federal Office for Consumer Protection and Food Safety, BVL, as well as in industry-sponsored papers. These rebuttals relied partly on unpublished industry-sponsored studies commissioned for regulatory purposes, which, it was claimed, showed that glyphosate is not a teratogen or reproductive toxin.
However, examination of the German authorities’ draft assessment report on the industry studies, which underlies glyphosate’s EU authorisation, revealed further evidence of glyphosate’s teratogenicity. Many of the malformations found were of the type defined in the scientific literature as associated with retinoic acid teratogenesis. Nevertheless, the German and EU authorities minimized these findings in their assessment and set a potentially unsafe acceptable daily intake (ADI) level for glyphosate. This paper reviews the evidence on the teratogenicity and reproductive toxicity of glyphosate herbicides and concludes that a new and transparent risk assessment needs to be conducted. The new risk assessment must take into account all the data on the toxicity of glyphosate and its commercial formulations, including data generated by independent scientists and published in the peer-reviewed scientific literature, as well as the industry-sponsored studies. FULL TEXT
Arbuckle TE, Lin Z, Mery LS., “An exploratory analysis of the effect of pesticide exposure on the risk of spontaneous abortion in an Ontario farm population,” Environmental Health Perspectives, 2001, 109: 8.
ABSTRACT: The toxicity of pesticides on human reproduction is largely unknown–particularly how mixtures of pesticide products might affect fetal toxicity. The Ontario Farm Family Health Study collected data by questionnaire on the identity and timing of pesticide use on the farm, lifestyle factors, and a complete reproductive history from the farm operator and eligible couples living on the farm. A total of 2,110 women provided information on 3,936 pregnancies, including 395 spontaneous abortions. To explore critical windows of exposure and target sites for toxicity, we examined exposures separately for preconception (3 months before and up to month of conception) and postconception (first trimester) windows and for early (< 12 weeks) and late (12-19 weeks) spontaneous abortions. We observed moderate increases in risk of early abortions for preconception exposures to phenoxy acetic acid herbicides [odds ratio (OR) = 1.5; 95% confidence interval (CI), 1.1-2.1], triazines (OR = 1.4; 95% CI, 1.0-2.0), and any herbicide (OR = 1.4; 95% CI, 1.1-1.9). For late abortions, preconception exposure to glyphosate (OR = 1.7; 95% CI, 1.0-2.9), thiocarbamates (OR = 1.8; 95% CI, 1.1-3.0), and the miscellaneous class of pesticides (OR = 1.5; 95% CI, 1.0-2.4) was associated with elevated risks. Postconception exposures were generally associated with late spontaneous abortions. Older maternal age (> 34 years of age) was the strongest risk factor for spontaneous abortions, and we observed several interactions between pesticides in the older age group using Classification and Regression Tree analysis. This study shows that timing of exposure and restricting analyses to more homogeneous endpoints are important in characterizing the reproductive toxicity of pesticides. FULL TEXT
Ludmilla Aristilde, Michael L. Reed, Rebecca A. Wilkes, Tracy Youngster, Matthew A. Kukurugya, Valerie Katz, and Clayton R. S. Sasaki, “Glyphosate-Induced Specific and Widespread Perturbations in the Metabolome of Soil Pseudomonas Species,” Frontiers in Environmental Science, 2017, 5:34, DOI: 10.3389/fenvs.2017.00034.
Previous studies have reported adverse effects of glyphosate on crop-beneficial soil bacterial species, including several soil Pseudomonas species. Of particular interest is the elucidation of the metabolic consequences of glyphosate toxicity in these species. Here we investigated the growth and metabolic responses of soil Pseudomonas species grown on succinate, a common root exudate, and glyphosate at different concentrations. We conducted our experiments with one agricultural soil isolate, P. fluorescens RA12, and three model species, P. putida KT2440, P. putida S12, and P. protegens Pf-5. Our results demonstrated both species- and strain-dependent growth responses to glyphosate. Following exposure to a range of glyphosate concentrations (up to 5 mM), the growth rate of both P. protegens Pf-5 and P. fluorescens RA12 remained unchanged whereas the two P. putida strains exhibited from 0 to 100% growth inhibition. We employed a 13C-assisted metabolomics approach using liquid chromatography-mass spectrometry to monitor disruptions in metabolic homeostasis and fluxes. Profiling of the whole-cell metabolome captured deviations in metabolite levels involved in the tricarboxylic acid cycle, ribonucleotide biosynthesis, and protein biosynthesis. Altered metabolite levels specifically in the biosynthetic pathway of aromatic amino acids (AAs), the target of toxicity for glyphosate in plants, implied the same toxicity target in the soil bacterium. Kinetic flux experiments with 13C-labeled succinate revealed that biosynthetic fluxes of the aromatic AAs were not inhibited in P. fluorescens Pf-5 in the presence of low and high glyphosate doses but these fluxes were inhibited by up to 60% in P. putida KT2440, even at sub-lethal glyphosate exposure. Notably, the greatest inhibition was found for the aromatic AA tryptophan, an important precursor to secondary metabolites. When the growth medium was supplemented with aromatic AAs, P. putida S12 exposed to a
lethal dose of glyphosate completely recovered in terms of both growth rate and selected metabolite levels. Collectively, our findings led us to conclude that the glyphosateinduced specific disruption of de novo biosynthesis of aromatic AAs accompanied by widespread metabolic disruptions was responsible for dose-dependent adverse effects of glyphosate on sensitive soil Pseudomonas species. FULL TEXT
Armiliato N, Ammar D, Nezzi L, Straliotto M, Muller YM, Nazari EM, “Changes in ultrastructure and expression of steroidogenic factor-1 in ovaries of zebrafish Danio rerio exposed to glyphosate,” Journal of Toxicology and Environmental Health A, 2014, 77:7, DOI: 10.1080/15287394.2014.880393.
Glyphosate is a broad-spectrum organophosphate (OP) herbicide, highly soluble in water, and when applied in terrestrial systems it penetrates into soil, eventually reaching the aquatic community and affecting nontarget organisms. The aim of this study was to evaluate the toxicity of glyphosate on ovaries of zebrafish (Danio rerio). Ovaries (n = 18 per triplicate) were exposed to 65 μg/L of glyphosate [N-(phosphonomethyl) glycine] for 15 d. This concentration was determined according to Resolution 357/2005/CONAMA/Brazil, which establishes the permissible concentration of glyphosate in Brazilian inland waters. Nonexposed ovaries (n = 18 per triplicate) were used as control. Subsequently, morphology and expression of steroidogenic factor-1 (SF-1) of exposed and nonexposed ovaries was determined. No apparent changes were noted in general morphology of exposed and nonexposed ovaries. However, a significant increase in diameter of oocytes was observed after exposure to glyphosate. When ovarian ultrastructure was examined the presence of concentric membranes, appearing as myelin-like structures, associated with the external membranes of mitochondria and with yolk granules was found. After glyphosate exposure, immunohistochemistry and immunoblotting revealed greater expression of SF-1 in the oocytes, which suggests a relationship between oocyte growth and SF-1 expression. These subtle adverse effects of glyphosate on oocytes raised a potential concern for fish reproduction. These results contribute to understanding glyphosate-induced toxicity to nontarget organisms, showing subcellular and molecular impairments that may affect reproduction in +female fish.
Medardo Avila-Vazquez, Agustina Etchegoyen, Eduardo Maturano and Luciana Ruderman, “Cancer and detrimental reproductive effects in an Argentine agricultural community environmentally exposed to glyphosate,” The Journal of Biological Physics and Chemistry, 2015, 15:3, DOI: 10.4024/09VA15A.jbpc.15.03
Argentina utilizes about 200 000 tonnes of glyphosate for its agriculture each year. People living near the fields treated with glyphosate often mention an increase in cancer and reproductive alterations. In Monte Maiz, an agricultural settlement with approximate population 8000, we conducted an environmental test assessing water, soil and particulate material contamination as well as an epidemiological study to detect and locate cases of cancer, abortion and genetic abnormality. The site utilizes annually 650 tonnes of glyphosate applied over an area of 65 000 ha. The glyphosate is concentrated and prepared for dispersal in the settlement. We detected glyphosate in particulate material and grain husks and it was found to be present at an even higher concentration on the ground in the village than in the surrounding rural area. The rate of spontaneous abortion in Monte Maiz is three times higher than the national average and the rate of occurrence of genetic abnormality is about twice the national average. Cancer occurrence is between two and three times the reference values for the entire nation with regard to incidence, prevalence and mortality. Although it is of course impossible to establish direct causality, the indicators that emerge from the correlated variables strongly suggest a public health problem of significant proportions, requiring immediate attention.
Medardo Avila-Vazquez, Eduardo Maturano, Agustina Etchegoyen, Flavia Silvina Difilippo, Bryan Maclean, “Association between Cancer and Environmental Exposure to Glyphosate,” International Journal of Clinical Medicine, 2017, 8:2, DOI: 10.4236/ijcm.2017.82007
BACKGROUND: Argentina, Brazil, Paraguay and Uruguay farm transgenic seeds glyphosate resistant. Argentina annually utilizes 240,000 tonnes of glyphosate in agriculture. A change in the profile of morbidity and mortality is perceived in agricultural areas; cancer seems to prevail. Monte Maíz is a typical argentine agricultural town with 8000 inhabitants; the Mayor and residents of Monte Maiz requested an environmental health study due to perceived increase in cancer frequencies.
METHODS: An exploratory ecological study was developed to assess the urban environmental contamination and the frequencies and distribution of cancer through an environmental analysis of pollution sources including measurements of pesticides in water, soil and grain dust, and a cross-sectional study of cancer patients that explore associations with different variables.
RESULTS: Glyphosate was detected in soil and grain dust and was found to be at an even higher concentration in the village soil than in the rural area. 650 tonnes are used annually in the region and manipulated inner town. We do not find other relevant sources of pollution. Cancer incidence, prevalence, and mortality are between two and three times higher than the reference values (Globocan 2012, WHO) for the entire nation (706/100,000 persons vs. 217/100,000; 2123/100,000 persons vs. 883.82/100,000 and 383/100,000 persons vs. 115.13/100,000, respectively).
CONCLUSION: This study detects high glyphosate pollution in association with increased frequencies of cancer in a typical argentine agricultural village, and by design, cannot make claims of causality. Other study designs are required, but if we corroborate the concrescence of high exposure to glyphosate and cancer. FULL TEXT