Offre de stage M2 Atmospheric Pesticides in the Gas and Particle Phases

Background

Pesticides used in agriculture can be released into the atmosphere during or after application and subsequently transported away from treated fields. Once in the atmosphere, they may be present in the gas phase or associated with atmospheric particles. This partitioning influences their transport, deposition and chemical transformation. However, the fate of pesticides in the atmosphere remains poorly understood, partly because of the challenges involved in measuring both phases simultaneously with sufficient time resolution.

Recent work carried out in our laboratory has demonstrated that pesticides in the gas phase can be monitored in real time using a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS). Coupling this instrument with the CHARON (CHemical Analysis of aeRosols ONline) module could extend this approach to the particle phase and provide a better understanding of pesticide behaviour in the atmosphere.

This internship will contribute to the development of an innovative analytical approach for high-time-resolution monitoring of atmospheric pesticides. It will assess the capabilities and limitations of PTR-ToF-MS/CHARON for characterising atmospheric pesticides and investigating their partitioning between the gas and particle phases.

Objectives and work plan

The aim of this internship is to assess the potential of PTR-ToF-MS coupled with a CHARON module for detecting and characterising pesticides present in both the gas and particle phases.

The work will begin with a literature review to select target compounds based on their physicochemical properties, the available scientific literature and the feasibility of their analysis by PTR-ToF-MS. Laboratory experiments will then be conducted to test their detection, optimise measurement conditions and characterise their mass spectral signatures.

Data analysis will allow to investigate pesticide partitioning between the two phases. Depending on the results, the work may also explore the detection of transformation products and their potential contribution to secondary organic aerosol formation.

The internship will therefore combine literature review, laboratory experiments, data analysis and interpretation of results. It will provide a better understanding of the capabilities and limitations of this analytical method for studying atmospheric pesticides.

Candidate profile

This internship is intended for a second-year Master's student (MSc) in Chemistry, Analytical Chemistry, Atmospheric Chemistry or Environmental Sciences.

An interest in experimental measurements and environmental issues is expected. Knowledge of mass spectrometry and data processing would be an advantage.

Additional skills and qualities: Ability to work independently and show initiative; Good organisational skills and ability to work as part of a team; Good written and spoken English skills.

Internship details :

Host institution and supervision

The internship will take place at INRAE, within the Ecophysiology and Physicochemistry of Biosphere–Atmosphere Interactions team of the EcoSys Joint Research Unit (UMR EcoSys).

The student will be supervised by Raluca Ciuraru and Carole Bedos. Raluca is an INRAE research scientist who specialises in characterising and analysing volatile organic compounds and secondary organic aerosols formed as a result of agricultural activities and practices. Carole is an INRAE senior research scientist who specialises in measuring and modelling pesticide volatilisation.

The student will also benefit from technical support during the experimental work and will have access to state-of-the-art analytical equipment available in our laboratory.

Duration: 5–6 months, starting in February or March 2027.

Location: EcoSys, AgroParisTech Campus, 22 place de l’Agronomie, 91120 Palaiseau, France. The laboratory is located on the Saclay plateau. It is accessible via Metro Line 18 and two bus routes from Massy-Palaiseau RER station. It is also approximately a 20-minute walk from Le Guichet station on RER Line B (Orsay).

Salary: Approximately €650, plus a contribution towards public transport costs, where applicable.

How to apply

Application documents: CV and cover letter to raluca.ciuraru@inrae.fr and carole.bedos@inrae.fr

Selection process: Applications will be reviewed, and shortlisted candidates will be invited for an interview.

Application deadline: 15 December 2026.