Children’s Exposure to Pesticides in Vineyard and Orchard Regions

In December 2022, the State Council of the Canton of Valais mandated Swiss TPH to conduct a study on children’s exposure to pesticides from vineyard and orchard treatments, and on the potential impact of this exposure on their respiratory health. The study involved 206 children from schools in three villages in Canton of Valais. The results were presented today at a press conference of the Canton de Valais in Sion.

“Of the 81 pesticides tested using silicone wristbands worn by the children, 36 were detected. On average, each child was exposed to 14 different pesticides. In addition, both pesticide biomarkers analyzed were detected in the urine samples.”, said Samuel Fuhrimann, study coordinator and Head of the Agricultural Health group at Swiss TPH. “Pesticide exposure levels were influenced by the season, the distance between the children’s homes and agricultural areas, and the size of these cultivated zones.”

Involving more than 200 school children

Swiss TPH conducted the study with children aged 6 to 13 years in the schools of Chamoson, Salgesch, and Saxon. These locations were selected based on the size and type of nearby vineyard and orchard areas. A total of 206 children participated in the exposure measurement. Exposure was measured during four periods: once outside the pesticide spraying season (January/February) and three times during the spraying season (April, May, and June). Exposure was measured using silicone wristbands worn by the children for one week during each sampling period and urine samples.

Six pesticides found in more than 40% of the children

Of the 81 pesticides tested, 36 were detected on the wristbands during at least one of the four measurement periods. Of these 36 pesticides, half (18) were detected infrequently (in fewer than 5% of children). Six – all fungicides – were more commonly found, detected in over 40% of the children. Every child was exposed to at least one pesticide during at least one measurement period (average per child: 14; minimum: 1, maximum: 32). Additionally, two urinary biomarkers for pesticide exposure were also detected.

Pesticide exposure was higher from April to June – months in which spraying is more common – than in January/February. Levels of exposure were also linked to the distance between the children’s homes and agricultural areas, as well as to the size of those areas.

The study also investigated potential links between exposure to the six most frequently detected pesticides on the wristbands and the two urinary pesticide biomarkers on one hand, and respiratory symptoms on the other. The analyses did not find any short-term associations between pesticide concentrations and respiratory symptoms such as coughing or difficulty breathing. However, spirometry tests (which measure e.g. lung volume and airflow) showed a slight reduction in some lung function parameters associated with two pesticides (propiconazole and metalaxyl).

Recommendations to reduce exposure

Based on the study results, Swiss TPH issued a series of recommendations aimed at reducing pesticide exposure. “We recommend that authorities support federal monitoring of spraying activities, inspect farms and other professional users such as sports clubs, and promote the use of safer alternatives,” said Fuhrimann. “We also support the continuation of human pesticide monitoring programmes, as the evidence they generate can foster constructive dialogue between government agencies, pesticide users, and concerned citizens, helping to promote responsible pest control and reduce potential health risks.”

Implementation measures by the Canton

The canton of Valais has announced that it will evaluate Swiss TPH’s recommendations for implementation and strengthen its efforts to reduce pesticide exposure. This includes supporting federal initiatives and developing a coordinated cantonal action plan to reinforce and expand existing measures across all pesticide users.

“This is the first study of its kind in Switzerland. As pesticides are a controversial topic, it is essential to have data to inform discussion and guide action,” said Nicole Probst-Hensch, Head of the Department of Epidemiology and Public Health at Swiss TPH. “This study was only possible thanks to the involvement of all stakeholders from the outset – including representatives from agriculture, schools, medicine, public authorities, and research.” She adds: “Further studies in form of a larger, national cohort are needed to better understand the long-term health effects.”