The Spanish Instituto Nacional de Seguridad y Salud en el Trabajo (INSST) published a technical guide on 29 September 2026 on bladder cancer caused by exposure to carcinogenic substances at work. Spain has the highest recorded incidence of bladder cancer in Europe: 22,295 new cases were diagnosed in 2022. Research estimates that 10 to 20 percent of all bladder cancer cases are linked to occupational exposure, while Spain’s occupational disease reporting system recorded only 16 cases as occupation-related between 2007 and 2021. The guide aims to help reduce this underreporting by giving occupational physicians, general practitioners, insurance doctors and medical inspectors guidance on recognition, prevention and assessment. Occupational bladder cancer and its underreporting are not unique to Spain: recognition of this type of occupational disease also lags behind its estimated true scale elsewhere in Europe, making the guide relevant to occupational hygienists and occupational physicians outside Spain.
Which occupations and sectors are at risk?
The guide identifies workers in the dye industry, rubber and leather processing, hairdressers working with certain hair dyes, firefighters, bus and truck drivers and railway staff who inhale substantial diesel exhaust, chimney sweeps, and workers in aluminium production as risk groups. They may be exposed to aromatic amines such as benzidine, 2-naphthylamine and 4-aminobiphenyl, to polycyclic aromatic hydrocarbons (PAHs) and to substances such as arsenic and acrylonitrile. Workers in the pharmaceutical and explosives industries and in chemical photo development are also mentioned. The guide further points to individual susceptibility: (former) smoking, a family history of bladder cancer and certain genetic variants (GSTM1, NAT2, PSCA) increase the risk for exposed workers. An additional risk arises when occupational exposure coincides with smoking: the guide emphasises that this combination does not rule out recognition as an occupational disease.
What does the guide recommend?
Central to the guide is the classic hierarchy of prevention: first eliminate or substitute the carcinogenic substance, failing that work in closed systems, and only as a last resort deploy technical extraction and personal protective equipment. Employers must check air concentrations against exposure limits and have exposed workers undergo periodic medical checks (at the start of, during and after exposure), aimed at early detection. To estimate the risk level per job, the guide recommends a simplified, qualitative assessment method (INSST guideline NTP 937) that ranks situations by action priority, allowing companies to prioritise the most urgent situations. For recognition as an occupational disease, the guide specifies a minimum exposure period of one year and an induction period of at least ten years between exposure and diagnosis; no maximum latency period is set.
Context
The World Health Organization’s International Agency for Research on Cancer (IARC) has long classified benzidine, 2-naphthylamine and 4-aminobiphenyl as Group 1, the category of substances with proven carcinogenic effects in humans, specifically for bladder cancer. Within the European Union, the Carcinogens, Mutagens and Reprotoxic Substances Directive (2004/37/EC) requires employers to substitute carcinogenic substances in the workplace or, where that is not possible, to minimise exposure; a binding occupational exposure limit applies to the aromatic amine o-toluidine.
Source: Oncoguía: cáncer de vejiga de origen profesional – Año 2026, 29 September 2026
Additional sources consulted: IARC Monographs (WHO), EU Directive 2004/37/EC (Carcinogens, Mutagens and Reprotoxic Substances)
