Table 5.

Effect of contacting time on inactivation of SARS-CoV in wastewater with low-concentration disinfectants^a

Disinfectants	Contacting time (min)	Inactivation rate (%)			Free residue chlorine (mg/L)
		SARS-CoV	f2 phage	E. coli (8099)
Chlorine
	1	43.77	15.79	0	0.39
	5	68.38	15.79	0	0.33
	10	100	18.32	14.29	0.40
	20	100	21.05	26.09	0.40
	30	100	31.58	20.21	0.35
Chlorine dioxide
	1	43.77	42.11	0	−
	5	68.38	26.32	17.39	−
	10	68.38	17.79	0	−
	20	68.38	26.32	14.29	−
	30	55.33	47.37	21.74	−

^aConcentration of chlorine and chlorine dioxide was 10 mg/L. SARS-CoV, 10^1.6TCID₅₀/ml; f₂, 1.9 × 10⁵ pfu/L; E. coli, 4.6 × 10⁵ cfu/L; temperature, 20 °C. (−) Not detected. Results from three experiments.