TY JOUR TI DETERMINING THE DEGREE OF TOXICITY OF NATURAL SURFACE WATER POLLUTED WITH OIL PRODUCTS BY METHODS NUMERICAL CHEMICAL ANALYSIS AND BIO-TESTING KW river Volga KW oil pollution KW bioassay KW quantitative chemical analysis KW bio-test KW test-organism KW Daphnia magna KW toxiс effect KW harmless concentration KW lethal concentration JO Vestnik of Astrakhan State Technical University. Series: Fishing industry AU Fomicheva, G.. AU Fyodorova, I.. AU Kamakin, A.. PY 2016 IS PB Astrakhan State Technical University