Rationale Engineered nanomaterials (ENMs) induce groundbreaking impacts by endowing unique properties to materials. However, uncertainties remain on their biological aftereffects. Entrusted by health and labour ministries, the French Public Health Institute launched since 2014 the EpiNano epidemiological surveillance program of workers potentially exposed to ENMs. The 2016–2020 national occupational health (OH) action plan inscribed the ENMs topic as of priority, with an enlargement to the construction and civil-engineering (CCE) sector. A scientific consortium was therefore established in order elaborate a standardised methodology to identify ENMs-exposed CCE workers.

Methods A comprehensive, structured PubMed review and web-search of technical documents was undertaken, complemented by in-depth experts’ interviews to collect contextual information regarding CCE nanoproducts.

Results Several methodological challenges were primarily revealed, pertaining primarily to : (i) Demarcating the target population: Involvement of a large number of companies (400,000) of all sizes and activities; Massive delegation to subcontractors; Heterogeneity of socioprofessional categories (from engineers to operators) and occupations (around 22); (ii) Unknown exposures’ circumstances: no CCE nanoproducts inventories neither detailed composition information; Unawareness of CCE actors of nanoproducts’ use; Heterogeneity of ENMs incorporated in various matrices (cement, coatings, paints…) with unknown ENM release/exposure potential; Potentially passive occupational exposures; Myriad of confusion factors with interactions with other risks at workplace; (iii) Capturing and following the eligible population: a complex topic to be addressed with a lot of pedagogy for adhering workers; epidemiological follow-up hampered by high turnovers, duration of construction sites and language barrier. Discussions are ongoing to overcome these methodological challenges. As a first step, an awareness campaign and the establishment of CCE nanoproducts’ inventory will be launched soon.

Conclusions An increase in CCE nanoproducts’ use is expected in the context of sustainable development and energy saving. This underscores the urgency to implement a specific surveillance system, by circumventing designing complexity.