Total petroleum hydrocarbons (TPHs) in groundwater of the Ecuadorian Amazon: Implications for human health

The Ecuadorian Amazon, particularly in the provinces of Sucumbíos and Orellana, has been heavily impacted by oil activity since the 1970s. In this context, this study carried out between March and June 2024 analyzed 161 groundwater samples taken from deep domestic wells in both provinces, with the aim of determining the concentrations of total petroleum hydrocarbons (TPH) and their implication on the health of consumers. The results showed that, in Orellana, TPH concentrations ranged between 0.11 and 7.30 mg/L, while in Sucumbíos they varied between 0.13 and 7.45 mg/L. More than 95% of water samples exceeded the maximum permissible limit of 0.2 mg/L for drinking water, according to the quality criteria established by Ecuadorian regulations. These levels of contamination reflect a significant exposure of local communities to health risks. In particular, the study revealed that the consumption of groundwater with high concentrations of TPH can generate non-cancer and carcinogenic risks greater than the levels recommended by the United States Environmental Protection Agency (USEPA). This situation endangers the health of people, especially children, who are the most vulnerable. The findings of this study highlight the urgency of implementing control measures and risk management strategies to mitigate contamination in areas affected by oil activity and protect the health of communities that depend on groundwater in the Amazon region.