Contaminated bean sprouts are being blamed for a salmonella outbreak that has made eight Waterloo Region residents sick. Of the eight people who have fallen sick, one is a two-year-old child, while the others range in age from their 20s to their 70s.

The outbreak has been traced to one large, Toronto-based company that distributes bean spouts widely throughout Ontario. Toronto Sun Wah Trading Inc. has voluntarily recalled all its mung bean sprouts, no matter what the code or best-before date.

It’s still unclear exactly how the bean sprouts were contaminated, but water isn’t likely to be the source, because the company uses Toronto tap water, said Dr. Hsiu-Li Wang, associate medical officer of health.

One possibility is that a sick employee transmitted the infection. Another possibility is that the seeds were contaminated. Toronto Public Health is investigating.