Glyphosate: ANSES reviews the monitoring data
Today, ANSES is publishing a summary of monitoring data on glyphosate and reviewing the knowledge currently available in France on its presence in water and food, as well as on blood concentration levels in humans.
As part of its phytopharmacovigilance scheme to detect adverse effects of plant protection products, ANSES collects monitoring data on the presence of substance residues in the environment, as well as on exposure and the impact on human health and ecosystems. This information is outlined in phytopharmacovigilance summary files for each substance, designed to be useful to all stakeholders, including the relevant government control services and authorities.
Today the Agency is publishing a file for glyphosate and aminomethylphosphonic acid (AMPA), its main metabolite.
Glyphosate in aquatic environments and groundwater
Tests conducted in 2017 show that glyphosate and AMPA are frequently found in surface water such as rivers and lakes (in 50% of samples for glyphosate and 74% for AMPA), leading to exposure of aquatic organisms. The concentrations observed are generally below the toxicity reference values in force for aquatic environments, with this value being exceeded only once in eleven years of monitoring.
In groundwater, glyphosate and AMPA were found in 3 to 4% of samples in 2017 with the water quality standard (maximum concentration of 0.1 µg/L for each substance) being exceeded annually at fewer than 1% of sampling points.
Glyphosate in drinking water
The presence of pesticide residues and their metabolites in drinking water is regulated by European Directive 98/83/EC, which requires permanent monitoring of drinking water quality. The maximum pesticide residue concentration in drinking water has been set at 0.1 µg/L for each substance. This value represents a standard for water quality, not for the health risk. The results of drinking water monitoring over the last ten years show that the 0.1 µg/L threshold was only exceeded for a very limited number of samples: 3 out of 7,596 samples for glyphosate in 2017.
For drinking water, the Vmax, a reference value derived from toxicity values, is a health threshold. It has been set for glyphosate and AMPA at a maximum concentration of 900 µg/L of water, which is 9,000 times higher than the water quality standard of 0.1 µg/L.
Glyphosate in food and oral exposure
Concerning dietary exposure, the main data come from studies conducted by ANSES: the 2016 Infant Total Diet Study, and the analysis of surveillance and control plans for adults and children in 2014. They show the presence of small amounts of glyphosate in foods including cereals, wine grapes and lentils. These studies show that dietary exposure of the French population does not exceed 1% of the acceptable daily intake (ADI), a reference health value for chronic toxicity risks. In order to improve the estimation of oral exposure, ANSES believes that other modes of exposure (inhalation and dermal) should be better documented and analysed.
Population monitoring surveys
The concentration of glyphosate in urine was analysed in two epidemiological studies conducted in France, one on a cohort of pregnant women who used herbicides (Inserm PELAGIE study over the period 2002-2006) and the other also on pregnant women (Santé publique France ELFE study over the year 2011).
Glyphosate and AMPA were found in respectively 43% and 36% of the urine samples collected from women in the PELAGIE study. The urinary concentrations observed ranged from 0.07 to 0.76 µg/L, while for AMPA they ranged from 0.06 to 1.22 µg/L. Glyphosate was quantified in 0.3% of samples in the ELFE study, but other data from studies published in the scientific literature, as well as from samples taken by associations, report urinary glyphosate concentrations of the same order of magnitude, around 1 µg/L. These quantities of glyphosate in urine of around 1 µg/L correspond to oral exposure below 1% of the acceptable daily intake.
These results will be supplemented by additional results from glyphosate monitoring in the urine of the general population, which will be available in 2020 (ESTEBAN study by Santé publique France).
Lastly, ANSES is continuing its work on glyphosate to improve current knowledge of its carcinogenic potential and to assess possible alternatives to this substance in the context of marketing authorisations.
Glyphosate reference values
For oral exposure, the toxicity reference value is expressed as an acceptable daily intake (ADI). The ADI for glyphosate (acceptable daily intake for chronic oral exposure), as well as the acute reference dose, have been estimated at 0.5 mg/kg of body weight/day. The chronic and acute toxicity thresholds for a 60 kg consumer therefore correspond to daily absorption of 30 mg of glyphosate.
Regarding drinking water, the Vmax is a management reference value, derived from the toxicity reference value, which ensures that the consumer is not exposed to any health risks. The Vmax for glyphosate and its metabolite AMPA together has been set at 900 micrograms per litre in drinking water.
In 2015, ANSES set up a phytopharmacovigilance scheme to monitor the potential adverse effects of pesticides on humans, animals and ecosystems. It helps gather information on environmental contamination and exposure, as well as the on emergence of phenomena of resistance to plant protection products. Through this scheme, the Agency funds studies to improve knowledge of the impact of plant protection products on humans and the environment.
Find out more about phytopharmacovigilance.