SARS spread through sewage? Experts refute concerns

The Water Environment Association of Ontario is working to dispel concerns that the virus associated with SARS might survive and be spread through biosolids. The Sierra Club of Canada, an environmental group, has suggested that the Coronavirus implicated as a likely cause of SARS might be passed to humans or animals through the spreading of biosolids as fertilizer by farmers.
WEAO president Tony Petrucci replied: “Any link between SARS and Biosolids is erroneous and based on speculation, not science.” A press release issued by the association at the end of May said: “Even if the virus is present in wastewater, it will not survive in the waste stream due to the level of biological treatment and destruction that occurs in the wastewater treatment facility.”
A study by the Water Environment Research Foundation has found that human viruses such as the Coronavirus have their microbial concentration reduced by 90% within hours of being anaerobically digested. Wastewater in Canada is treated in process tanks for several days, and solids are transferred to digesters where they are treated for a further minimum 15 days.
The association is also refuting concerns that the virus could spread through inadequate plumbing. It quotes Dr. Donald Low, a microbiologist in chief at Toronto’s Mount Sinai Hospital, saying that the circumstances whereby SARS may have spread in an apartment complex in Hong Kong due to leaking wastewater pipes were very unlikely to happen in Canada.
There have been some suggestions that the virus could survive in diarrhea for up to four days, or even longer. In this regard, the WEAO press release quoted Dr. Syed Sattar, of the University of Ottawa, who believes that SARS spread through wastewater is unlikely: “Even if the Coronavirus was found to be excreted in feces, it may not survive in the waste stream, since the dilution factor in the sewage system is expected to be immense and the Coronavirus is most likely to lose its infectivity quite rapidly in the waste stream and in the sewage treatment process. The Water Environment Association of Ontario represents individuals in the industry. See www.weao.org