Exposures and cancer incidence near oil fields in the Amazon basin of Ecuador

Objectives - To examine environmental exposure and incidence and mortality of cancer in the village of San Carlos surrounded by oil fields in the Amaz on basin of Ecuador. Methods - Water samples of the local streams were analyzed for total petrol eum hydrocarbons (TPHs). A preliminary list of potential cancer cases from 1989 to 1998 was prepared. Cases were compared with expected numbers of can cer morbidity and mortality registrations from a Quite reference population . Results - Water analysis showed severe exposure to TPHs by the residents. T en patients with cancer were diagnosed while resident in the village of San Carlos. An overall excess for all types of cancer was found in the male po pulation (8 observed v 3.5 expected) with a risk 2.26 times higher than exp ected (95% confidence interval (95% CI) 0.97 to 4.46). There was an overall excess of deaths for all types of cancer (6 v 1.6 expected) among the male population 3.6 times higher than the reference population (95% CI 1.31 to 7.81). Conclusions-The observed excess of cancer might be associated with the poll ution of the environment by toxic contaminants coming from the oil producti on.