environmental issue in Russia
... that a top environmental issue in Russia is water pollution, affecting 75% of the country's surface water?
... that a top <b id="mwEUU"><a href="./Environmental_issues_in_Russia" id="mwEUY" rel="mw:WikiLink" title="Environmental issues in Russia">environmental issue in Russia</a></b> is <a href="./Water_pollution" id="mwEUc" rel="mw:WikiLink" title="Water pollution">water pollution</a>, affecting 75% of the country's <a href="./Surface_water" id="mwEUg" rel="mw:WikiLink" title="Surface water">surface water</a>?