Current-use pesticides (CUPs) are crucial to modern agricultural practices, yet their off-target transport poses environmental and human health risks. Passive air sampling using polyurethane foam (PUF) is a practical method for monitoring CUPs occurrence, transport, and temporal patterns [1]. In parallel, biomonitoring using pollinators has emerged as a valuable approach to investigate CUPs distribution and persistence in the environment [2].

This study evaluates the persistence and distribution of CUPs using an integrated approach that combines passive air sampling with PUF disks and biomonitoring through bee pollen analysis. Five beehives and thirteen PUF samplers were strategically installed around a controlled area covering 39 agricultural fields (~600,000 m²). Detailed pesticide application records, including the specific compounds used, quantities, and locations, were compiled, along with continuous meteorological data. Weekly bee pollen and biweekly PUF samples were collected from late April to late October 2023.

Airborne pesticide concentrations were estimated using a previously published model for effective sampling volumes [3], adapted to CUPs physicochemical properties and local meteorological conditions. The results revealed short-term changes in pesticide levels and dispersion over distances greater than two kilometres from their application sites. Additionally, bee pollen analysis confirmed that pesticides persisted on crops beyond their intended periods, contaminating untreated and off-crop areas more than 800 meters from application sites. Fractionation of pollen samples by plant species further confirmed multiple contamination sources, including directly treated crops and untreated off-crop plants.

Overall, this study provides a comprehensive view of how CUPs are distributed and persist in the environment. The presented approach improves the spatial and temporal resolution of CUPs contamination by revealing new perspectives on pesticide presence, transport, and longevity. These findings highlight significant exposure risks for non-target organisms, particularly pollinators, and emphasise the need for complementary sampling techniques to guide effective mitigation and environmental protection policies.

[1] V. H. Estellano, K. Pozo, C. Efstathiou, K. Pozo, S. Corsolini, and S. Focardi, (2015) “Assessing levels and seasonal variations of current-use pesticides (CUPs) in the Tuscan atmosphere, Italy, using polyurethane foam disks (PUF) passive air samplers,” Environmental Pollution, vol. 205, pp. 52–59.

[2] C. Kast, J. Müller, and M. Fracheboud, (2024), “Temporal entry of pesticides through pollen into the bee hive and their fate in beeswax,” Environmental Science and Pollution Research, vol. 31, no. 51, pp. 61060–61072.

[3] N. J. Herkert, A. Martinez, and K. C. Hornbuckle, (2016), “A Model Using Local Weather Data to Determine the Effective Sampling Volume for PCB Congeners Collected on Passive Air Samplers,” Environ Sci Technol, vol. 50, no. 13, pp. 6690–6697