144
Discussion
waters, sea waters, and general water quality monitoring (Water Quality Criteria, 1968; Standard
Methods, 1971).
The omission by the authors of the details used in water sampling was obviously due to space
limitations, but it is regretable that no mention was made of their neutralization procedure at the time
of collection of chlorinated water used in microbiological testing, the technique used in measurement
of chlorine levels in their water, and their salmonella evaluation procedure. I also assumed that the
membrane filter procedure for Escherichia coli I was done at 44°C and not at 40°C, as reported in the
paper available to me for review.
REFERENCES
BERG, G. 1971. Integrated Approach to Problem of Viruses in Water. Proc. Amer. Soc. Civil Engr.,
Sanitary Engr. Division, 97, SA 6, 867-882.
BERG, G. 1972. Reassessment of the Virus Problem in Sewage and in Surface and Renovated Waters.
Presented at the Sixth International Conference on Water Pollution Research, Jerusalem, Israel,
June 18-23, 1972.
CLIVER, D.O. 1968. In Transmission of Viruses by the Water Route (G. Berg, ed.), Interscience
Publishers, New York, p. 139-141.
European Standards for Drinking-Water, 2nd ed. 1970. World Health Organization, Geneva, Switzerland.
GELDREICH, E.E. 1966. Sanitary Significance of Fecal Conforms in the Environment, Publ. WP-20-3,
Federal Water Pollution Control Administration.
MELNICK, J.L. 1971. Detection of Virus Spread by the Water Route. In Proc. Thirteenth Water
Quality Conference, Virus and Water Quality: Occurrence and Control, Univ. Illinois, Urbana, p.
114-124.
National Technical Advisory Committee, Water Quality Criteria. 1968. Federal Water Pollution Control Administration, Washington, D.C.
Public Health Service Drinking Water Standards, Publ. No. 956. 1962. Public Health Service,
Washington, D.C.
RAO, V.C. 1971. A Simple Method for Concentrating and Detecting Viruses in Wastewater. Presented
at the Second International Congress for Virology, Budapest, Hungary, June 27-July 3, 1971.
SCARPINO, P.V. In Manuscript.
SHUVAL, H.I., FATTAL, B., CYMBALISTA, S. and GOLDBLUM, N. 1969. The Phase-Separation
Method for the Concentration and Detection of Viruses in Water. Water Research, 3, 225-240.
Standard Methods for the Examination of Water and Wastewater, 13th. ed. 1971. American Public
Health Association, New York.
WALLIS, C.,GRINSTEIN,S., MELNICK, J.L., and FIELDS, J.E. 1969. Concentration of Viruses from
Sewage and Excreta on Insoluble Polyelectrolytes. Appl. Microbiol, 18, 1007-1014.
Dr. Coin, France
Virus inactivation was carried out by the ozonization of more than 1,500,000 cubic metres of raw
water. This treatment had been progressively installed in plants during the last 10 years.
H. Leclerc, France
Hepatitis is the essential problem. How is one sure of its removal by break point chlorination?
Polio virus could be considered as an indicator virus.
Answer:
There is no reason to believe that the virus of infectious hepatitis should behave differently from
other viruses in respect to breakpoint chlorination. Neefe (1947), on human volunteers, has shown the
inactivation of the virus by breakpoint chlorination. I agree that the polio virus could possibly be used
as an indicator virus until such time as the infectious hepatitis virus can be isolated in the laboratory.
Aaron Meron, Israel
The effectiveness of breakpoint chlorination is low but the pH is high in stabilization pond
effluents.
Answer:
The increased concentration in the free residual chlorine of the hypochlorite ion at high pH levels
will account for this.
Discussion
waters, sea waters, and general water quality monitoring (Water Quality Criteria, 1968; Standard
Methods, 1971).
The omission by the authors of the details used in water sampling was obviously due to space
limitations, but it is regretable that no mention was made of their neutralization procedure at the time
of collection of chlorinated water used in microbiological testing, the technique used in measurement
of chlorine levels in their water, and their salmonella evaluation procedure. I also assumed that the
membrane filter procedure for Escherichia coli I was done at 44°C and not at 40°C, as reported in the
paper available to me for review.
REFERENCES
BERG, G. 1971. Integrated Approach to Problem of Viruses in Water. Proc. Amer. Soc. Civil Engr.,
Sanitary Engr. Division, 97, SA 6, 867-882.
BERG, G. 1972. Reassessment of the Virus Problem in Sewage and in Surface and Renovated Waters.
Presented at the Sixth International Conference on Water Pollution Research, Jerusalem, Israel,
June 18-23, 1972.
CLIVER, D.O. 1968. In Transmission of Viruses by the Water Route (G. Berg, ed.), Interscience
Publishers, New York, p. 139-141.
European Standards for Drinking-Water, 2nd ed. 1970. World Health Organization, Geneva, Switzerland.
GELDREICH, E.E. 1966. Sanitary Significance of Fecal Conforms in the Environment, Publ. WP-20-3,
Federal Water Pollution Control Administration.
MELNICK, J.L. 1971. Detection of Virus Spread by the Water Route. In Proc. Thirteenth Water
Quality Conference, Virus and Water Quality: Occurrence and Control, Univ. Illinois, Urbana, p.
114-124.
National Technical Advisory Committee, Water Quality Criteria. 1968. Federal Water Pollution Control Administration, Washington, D.C.
Public Health Service Drinking Water Standards, Publ. No. 956. 1962. Public Health Service,
Washington, D.C.
RAO, V.C. 1971. A Simple Method for Concentrating and Detecting Viruses in Wastewater. Presented
at the Second International Congress for Virology, Budapest, Hungary, June 27-July 3, 1971.
SCARPINO, P.V. In Manuscript.
SHUVAL, H.I., FATTAL, B., CYMBALISTA, S. and GOLDBLUM, N. 1969. The Phase-Separation
Method for the Concentration and Detection of Viruses in Water. Water Research, 3, 225-240.
Standard Methods for the Examination of Water and Wastewater, 13th. ed. 1971. American Public
Health Association, New York.
WALLIS, C.,GRINSTEIN,S., MELNICK, J.L., and FIELDS, J.E. 1969. Concentration of Viruses from
Sewage and Excreta on Insoluble Polyelectrolytes. Appl. Microbiol, 18, 1007-1014.
Dr. Coin, France
Virus inactivation was carried out by the ozonization of more than 1,500,000 cubic metres of raw
water. This treatment had been progressively installed in plants during the last 10 years.
H. Leclerc, France
Hepatitis is the essential problem. How is one sure of its removal by break point chlorination?
Polio virus could be considered as an indicator virus.
Answer:
There is no reason to believe that the virus of infectious hepatitis should behave differently from
other viruses in respect to breakpoint chlorination. Neefe (1947), on human volunteers, has shown the
inactivation of the virus by breakpoint chlorination. I agree that the polio virus could possibly be used
as an indicator virus until such time as the infectious hepatitis virus can be isolated in the laboratory.
Aaron Meron, Israel
The effectiveness of breakpoint chlorination is low but the pH is high in stabilization pond
effluents.
Answer:
The increased concentration in the free residual chlorine of the hypochlorite ion at high pH levels
will account for this.