Occupational heat risk among migrants in Spain’s agricultural sector is worsened by socioeconomic inequality

The occupational heat risk faced by migrant farm workers in Spain goes beyond environmental factors and is compounded by socioeconomic inequalities. This is the main conclusion of a study carried out as part of the CATALYSE project by the Barcelona Institute for Global Health (ISGlobal), a centre supported by the ”la Caixa” Foundation, and published in the International Journal for Equity in Health. The findings show that these workers often face the dilemma of protecting their health or safeguarding their income, while their protection frequently depends more on employers’ willingness than on guaranteed rights.

Giving migrant farm workers a voice to better understand their experiences

Climate change is intensifying exposure to heat, with heatwaves becoming increasingly frequent and severe. Heat stress can cause anything from dizziness and cramps to fainting, while also increasing the risk of workplace injuries, worsening pre-existing conditions and impairing kidney function over the long term. In Spain, a strong link has been documented between rising temperatures and workplace injuries in the agricultural sector.

“Until now, no study had examined the experiences of migrant agricultural workers dealing with heat in Spain. Our aim was to understand how they experience and cope with occupational heat stress,” explains Marlena van Selm, predoctoral researcher at ISGlobal and first author of the study.

The team interviewed 30 migrant agricultural workers —24 men and six women, mainly from sub-Saharan and North Africa— in Almería, Lleida and Huelva. The interviews were recorded, transcribed and analysed using reflexive thematic analysis.

Heat and precarious working conditions limit people’s ability to protect their health

Participants described extreme heat as a routine part of their work and reported frequent symptoms of heat stress, including dizziness, exhaustion and fainting. Conditions were particularly severe inside greenhouses, where temperatures can rise far above outdoor levels if adequate ventilation and shading measures are not in place. Although many workers tried to protect themselves by drinking water, wearing suitable clothing or taking breaks, these measures were often limited by pressure to maintain high work rates and minimise rest periods.

The study shows that the ability to prevent the effects of heat depends largely on social and economic factors. Job insecurity, irregular immigration status, language barriers and the fear of losing employment make it difficult for workers to demand better conditions or stop working during periods of extreme heat. Housing conditions also play a role. Many participants were living in poor-quality accommodation with very high indoor temperatures, making it difficult to recover from heat exposure after the working day.

Protection against heat depends more on employers than on guaranteed rights

Although Spanish legislation requires working conditions to be adapted during periods of high temperatures, interviewees pointed out that, in practice, their protection largely depends on the goodwill of employers.

“Reducing the health risks associated with heat stress requires clearer and enforceable preventive measures, as well as improvements in working conditions. It also means addressing other structural vulnerabilities, such as access to decent housing, in a context where temperatures are rising due to climate change,” concludes Ana Requena-Méndez, head of ISGlobal’s Migration Health group and coordinator of the study.

Reference

van Selm, L., Voorhis, C., Williams, S., Izuzquiza-Regalado, D., Notario-Gallego, S., Diop, S., Evangelidou, S., Briones-Vozmediano, E., & Requena-Méndez, A. (2026). Lived experiences of heat stress among migrant agricultural workers in Spain: a qualitative study. International Journal for Equity in Health, 25(1). https://doi.org/10.1186/s12939-026-02850-x