Researchers from the University of Galway have found that one quarter of families that took part in a study were to have low levels of exposure to glyphosate.

68 families, 14 of which were from a farming background, took part in the first study of its kind in Ireland to investigate the background level of exposure to the herbicide.

Between 2019 and 2020, urine samples from 226 people were tested for glyphosate and its main human metabolite, aminomethylphosphonic acid (AMPA).

The study, carried out in collaboration with the Institute for Prevention and Occupational Medicine in Bochum, Germany and the German Environment Agency, also involved participants filling out a detailed dietary and lifestyle questionnaire.


Researchers found that glyphosate was detectable in 26% of samples, while AMPA was found in 59% of samples.

The daily intakes for participants were back-calculated from urinary glyphosate concentrations and compared to the acceptable daily intake.

Calculated intakes were equivalent to 3% or less of the European Food Safety Authority (EFSA) acceptable level.

There was no statistical difference between farm and non-farm families’ exposures, though higher concentrations were detected among some fathers living on farms, possibly because they sprayed glyphosate-based pesticide products the day before sampling.

The researchers said that the higher detection frequency for AMPA may be due to residues on foods and water.

They also found maximum exposures to glyphosate are low compared to the current acceptable daily intake set by the EFSA without presenting an appreciable health risk.

This study was carried out as a European project on human biomonitoring (the HBM4EU project), which has identified a number of substances, including glyphosate, for which further information is needed.

This is to better understand the potential risk posed to human health from such substances.


Glyphosate is the active ingredient in over 750 products and is the most common herbicide used globally.

However, the potential adverse health effects of the chemical have come under increasing scrutiny in recent years.

Glyphosate is currently approved for use in the EU, a review of this approval is currently underway with a final conclusion due from the EFSA in July 2023.

The International Agency for Research on Cancer (IARC) classified glyphosate as “Group 2A – probably carcinogenic to humans” in 2015.

The European Chemical Agency’s (ECHA) Committee for Risk Assessment (RAC) has classified the herbicide as causing serious eye damage and being toxic to aquatic life.

It has stated that it is not justified to classify glyphosate as a carcinogen.

Dr. Alison Connolly, exposure scientist and Dr. Marie Coggins, senior lecturer in Exposure Science at University of Galway

Dr. Alison Connolly, the exposure scientist who conducted the research while at University of Galway, said:

“This study produced important results on human exposures to a chemical of public concern and is particularly timely with the European Commission currently re-evaluating glyphosate.

“Though the quantifiable levels were low, it is essential to understand how chemical exposures can occur among different groups, particularly vulnerable people such as children.

“This information is necessary for conducting robust regulatory risk assessments, managing exposure levels, and fully understanding their effect on human health.

“This study also demonstrated how beneficial human biomonitoring is for evaluating chemical exposures.”