It is apparent that the EPA funded evaluation by S.C. Reed et al (1996) on the living machine in Frederick required more time for LT to correct it than Reed et al to write it.

To Michael Shaw, Richard Boylan and others :
Qs: could you tell us about the US EPA (Environmental Protection Agency) and its regulation system on LM ? Why was this  EPA evaluation presented at the Vienna Conference; are all EPA independent evaluations always presented at international conferences ?

Hans Brix <hans.brix@BIOLOGY.AAU.DK> quoted from the paper by S.C. Reed, J. Salisbury, L. Fillmore and R.K. Bastian, entitled: "An evaluation of the 'Living Machine' wastewater treatment concept" (presented at the 5th Int. Conf, on Wetlands Systems for Water Pollution Control held in Vienna 1996) that:

>(1) The plants used on and in the 'Living Machine' provide a marginal
>contribution to treatment and are not essential for realization of process
>treatment goals.

I see this statement as a highly incorrect one, so I wonder under what context was this statement made by Sherwood Reed.

Here is an info message which was distributed today via another list with research results showing that plants in potable water and secondary sewage increase in the die-off of salmonella and E.coli.

------
sender: THCLAX00@UKCC.UKY.EDU

 American Society for Microbiology
 20-May-98

                   Wetlands Remove Pathogens from Wastewater

 Mohammad Karim Shantz
 #429 University of Arizona
 Tucson, AZ 85721
 520/621-6910
(email: not available)

 Paper Q-135, Session 203-Q

Salmonella spp. is one of the major concerns of public health in the U.S. because of the more than 30,000 reported cases of Salmonella poisoning each year. Conventional wastewater treatment technologies depend on disinfection to reduce pathogen population. In this study we examined the survival of E. coli and Salmonella typhimurium in six different wetland systems receiving either potable water or secondary sewage which contained different aquatic plants. Our results suggest that the presence of aquatic plants significantly increases die-off of both bacteria in potable water and secondary sewage, indicating that vegetative wetland could provide an alternative method for reduction of bacterial pathogens in wastewater. The experiment was performed by Mohammad R. Karim and Dr. Edward P. Glenn in r. Charles P. Gerba's laboratory in the Department of Soil, Water and Environmental Science at the University of Arizona, Tucson. Funding was provided by United States Geological Survey and the results will be presented at the 98th General Meeting of the American Society for Microbiology in Atlanta Georgia on May 20, 1998. E. coli and S. typhimurium were added at a concentration of 1,000,000 cfu/ml to six wetland systems. Four wetland systems receiving potable water contained a combination of Cattail, Iris Lily, Taro, Duckweek and Elodea. Two other wetland systems receiving secondary unchlorinated sewage contained Water Hyacinth and Duckweed. Potable water and secondary sewage without the presence of any aquatic plants were used as controls. Bacterial die-off in potable water and secondary sewage was significantly higher when aquatic plants were present in these systems. We examined whether any antibiotic-like substance or inhibitory substances were released by the plants in the studied wetlands, which could enhance bacterial die-off. No antibiotic or inhibitory substances were found in these wetland waters. Further work on the survival of E. coli in non-sterile, filter sterilized and autoclaved wetland water indicated that the plausible mechanism of bacterial die-off in constructed wetlands is through microbial competition or predation. Vegetative wetland is a natural system with no added chemicals in it. These results along with the other published literature in this area suggest that this natural system might be used for microbial water quality improvement in the future.