The environmental impact of some of the main pesticides used in viticulture and on other crops may have been ‘significantly underestimated’, a new study has found.
According to the study, the results of which were presented at the Goldschmidt Conference in Prague earlier this month, the nine pesticides that were examined exceeded the Stockholm Convention’s 2-day half-life limit in the atmosphere, with some persisting for several weeks.
The global use of pesticides has doubled since 1990, according to the UN Food and Agriculture Organisation, with this study raising concerns about the potential impact on health and the environment, according to the researchers.
Regulatory frameworks
The research team, led by Boulos Samia of Aix-Marseille University and including colleagues from Aix-Marseille University and CNRS, France have called for the urgent updating of regulatory frameworks governing the use of pesticides.
Current European regulations only consider the atmospheric lifetimes of pesticides based on their gas phase, with the research team calling for their reclassification as ‘persistent organic pollutants’.
‘Limited understanding’
“These pesticides are used in huge quantities across Europe and our research shows limited understanding about how they endure in the lower atmosphere,” Samia commented.
“In the past they have been studied in their gas phase, and this is how EU regulations are set. Yet our research shows they are far less reactive in their particulate phase, meaning that they degrade more slowly. Because of this, they should be considered as persistent organic compounds with potential for long-range transport, and that the models used to test their safety do not go far enough.”
A second experiment undertaken by the team saw them examine the degradation mechanisms of pesticides, observing several toxic and non-commercially available molecules. Finally, the researchers examined how temperature and relative humidity affect the partitioning of the pesticide molecules between gas and the particle phase, finding discrepancies compared with current models of their behaviour.
“Together these experiments suggest that pesticides used in agriculture need updated regulatory frameworks that take into account their particulate phase behaviour in the atmosphere,” Samia added. Read more here.
