Researchers in San Diego say they have detected a poisonous substance in the Tijuana River Valley as a result of the high volume of raw sewage flowing from Mexico into the area.
Concretely, they say they found dangerous levels of hydrogen cyanide and hydrogen sulfide, leading them to abandon their work in the area. The researchers from San Diego State University and UC-San Diego stopped their work as Dr. Kim Prather, director of the Center for Aerosol Impacts on Chemistry of the Environment at UC San Diego, said she could not continue putting them "at this level of risk."
