<prompt> Proposed guideline value for Radioactivity in drinking water is:Gross a activity 0.1 BqL and Gross b activity 1.0 BqLGross a activity 1.0 BqL adn Gross b activity 0.1 BqLGross a activity 1.0 BqL and Gross b activity 10.0 BqLGross a activity 10 BqL and Gross b activity 1.0 BqL  <response>: Key guidelines aspects of WHO recommended drinking water quality: Colour 15 true colour units TCU Turbidity 1 nephlometric turbidity units NTU pH: 6.5-8.5 Total dissolved solids TDS 500 mgLitre Zero pathogenic microorganisms Zero infectious viruses Absence of pathogenic protozoa and infective stages of helminthes Fluoride 1.0 ppm 0.5-0.8 ppm: Optimum level Nitrates 45 mgLitre Nitrites 3 mgLitre Gross alpha radiological activity 0.5 BqLitre new guidelines -WHO Gross Beta radiological activity 1.0 BqLitre new guidelines-WHO Ref: Park 25th edition Pgno: 762 