“Sick building syndrome, according to the World Health Organization (WHO), recognizes the syndrome in buildings that at least 20 per cent of the occupants complain of the same the same illness: it can be headache, it can be diarrhea, it can be gastrointestinal illnesses,” says Gil Blutrich, founder and CEO of Clear, an air and water purifying company in Toronto. New York experienced water problems due to old infrastructure. “When it started to run through the pipes in New York city, the average age of the piping is over 100 years old so when the pipe started to rust, only 75 per cent reached the building, the rest disappeared, dissipated through a hole in the system.” This produced a problem called the “last mile syndrome,” says Blutrich, where the water is coming out and pathogen and bacteria is coming in.