The riverine drainage system of the Pasión and its tributaries covers an area of over 5,000 square kilometres (1,900 sq mi) and forms a watershed for a substantial portion of the present-day Guatemalan department of Petén's western half.[2][a]
On June 6, 2015, residents around La Pasión River reported finding of a high count of dead fish floating in the river.[4] On June 11, 2015, Guatemala's authorities inspected palm oil company "Reforestadora de Palmas de Petén, S.A." (REPSA), located in Sayaxché, and found traces of Malathion, a pesticide, in the company's tributaries leading to La Pasión River.[5] Tranquilino Xojalaj, administrator of REPSA, declared that heavy rain caused the treatment wells to flood into the river,[6] however the company denied responsibility, stating that they do not use Malathion as a pesticide.[7]
By June 15, 2015, dead fish had been found over 105 kilometres (65 mi) downstream.[8] The pollution might have entered the Usumacinta River, which travels all the way to México.[9]
Houston, Stephen D. (1993). Hieroglyphs and History at Dos Pilas: Dynastic Politics of the Classic Maya. Austin: University of Texas Press. pp. 4 and 10. ISBN0-292-73855-2.