Thermal injury resulting from drinking very hot beverages has been incriminated as a risk factor for oesophageal cancer, although no information is available on the lesions caused by this injury in human or experimental animals. The drinking of hot maté tea is very common in areas of moderately high incidence of oesophageal cancer in south-eastern areas of South America. This study investigated the prevalence of precancerous lesions of the oesophagus in 60 unskilled male workers, of whom half were daily maté drinkers and the remainder were non-maté drinkers. These 2 groups were matched for age, smoking and alcohol intake. Maté drinkers were 2.2 times more likely (p = 0.046) to develop histologically confirmed oesophagitis than non-maté drinkers.