The French National Centre for Scientific Research (CNRS) is offering a fully funded 3-year PhD position to investigate the ecotoxicological effects of PFAS on coral reef fish in Okinawa, Japan.

Job Description

Thesis Topic

Ecotoxicology of PFAS in a reef medium in a coastal damsy fish in Okinawa: a transcribentic coupling approach, field studies and controlled bioassays.

Forty percent of the world’s population lives within 100 kilometers of the coast, causing unprecedented pollution. In tropical and subtropical regions, coral fish, which are essential to the ecology of reefs, are thus subjected to many stresses of anthropogenic origin. In particular, per- and polyfluoroalkylated substances (PFAS) constitute a class of persistent pollutants commonly detected in coastal environments. In Japan, Okinawa, the activities of U.S. military bases are linked to high concentrations of PFAS at river mouthpieces. Their chemical stability and potential for bioaccumulation raises major concerns about their effects on marine organisms, which are still largely under-explored.
The interactions between gene expression and the environment are increasingly being studied in a wide range of organisms and are very promising in terms of ecological monitoring. With the rise of sequencing technologies in recent decades, transcriptomic analyses are frequently used to understand the metabolic and physiological pathways affected in organisms exposed to pollutants.

The main objectives will be:

1. to explore the potential of dose-response modelling approaches to identify, in the transcriptomes of young fish (Chrysiptera cyanea), the signatures of chronic and environmental exposure to PFAS,
2. to establish the link between the transcriptional effects of laboratory and field PFAS exposure in Okinawa, and
3. to characterize the effects of the PFAS.

The project is a collaboration between the Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC, France), the CNRS International Research Laboratory EARLY, and the Okinawa Institute of Science and Technology (OIST), Japan.

Requirements

Applicants should possess:

• A Master’s degree (or equivalent engineering degree) in Environmental Toxicology, Ecotoxicology, Marine Sciences, Ecology, Biodiversity, Evolutionary Biology, Molecular Biology, or a related discipline.
• Knowledge and Know-how: We are looking for someone with a solid background in biology to address the molecular basis of the stress response of organisms.
• Previous experience in the study of reef environments, ecotoxicology, landscape ecology, bioinformatics and/or data analysis (Software R), ideally related to gene expression, will be appreciated.
• A scuba diving experience (holder of the CAH 1B) would be a plus.
• We are looking for a well-organized and rigorous person, volunteering for fieldwork, in the laboratory, and in the office for data analysis, bibliographic research and writing.
• Finally, it is necessary to have writing, presentation and communication skills in English to interact with the international network of the project.

Location: Metz, France, and extended research stays (3–6 months) at Okinawa Institute of Science and Technology (OIST), Japan will be organized to conduct field sampling and laboratory experiments.

Duration: 36 months

Start Date: 1 October 2026

Salary: Approximately €2,300 gross per month

How to Apply

The application and the requested documents below must be submitted using the Apply link on the offer page emploi.cnrs.fr.

• A detailed CV (including the contact details of two referents and the transcripts of Master 1 and Master 2 (or equivalent)
• Motivation letter

Any questions may be addressed to elise.billoir@univ-loraine.fr and vincent.laudet@oist.jp

Application Deadline

27 June 2026 (00:00 CET)