Sayaxché (Spanish pronunciation: [saʝaʃˈtʃe]) is a municipality in the El Petén department of Guatemala, on the Río La Pasión river.

[3] The investors are trying to turn Guatemala into one of the main palm oil exporters, in spite of the decline on its international price.

[4] On June 11, 2015, Guatemala's authorities inspected palm oil extracting company "Reforestadora de Palmas de Petén, S.A." (REPSA), located in Sayaxché, and found traces Malathion in the company's tributaries leading to Río 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 is denying any involvement in the disaster,[7] stating that they do not use Malathion as pesticide.

As of June 15, 2015, contamination has extended to over 105 km downstream and is affecting over 5,600 families (around 30,000 residents) from 16 communities by the riverside.