Inactivation by bromine of single poliovirus particles in water.

Quantitative electron microscopy shows that Freon-extracted poliovirus, velocity banded in a sucrose gradient, contains over 95% single particles. This well-dispersed virus reacts quite rapidly with bromine in turbulent flowing water, losing plaque titer at the rate of one log10 unit in 10s at pH 7, 2 C, and at a bromine concentration of 2.2 muM. At 10 and 20 C the rate of disinfection (log10 plaque-forming units per second) is faster, and at both temperatures it increases in approximately linear fashion with increasing bromine concentration. At 2 C such a linear relationship is not observed.