The dissolved load of the Amazon River is generally considered to be lowlyimpacted by anthropogenic activities. In this work, based on the chemical and hydrologicaldatabase of the Environmental Research Observatory—HYBAM (http://www.ore-hybam.org), we explore the importance of the Peruvian Foreland petroleum activity on the dis-solved Na and Cl fluxes of the Amazon River. The main result of this study allows ussuggesting that oil extraction activity, concentrated in the El Tigre River basin, a small foreland watershed in the Peruvian Amazon, influenced drastically the Na and Cl expor-tation of the Amazon River during the 2006–2007 period. During these years, the dis-solved exportations of this basin represented almost 20 % of the annual dissolved ClAmazon flux and almost 12 % of the annual dissolved Na Amazon flux for a mean annualdischarge\1 % of the Amazon River discharge. Since th...