Ontario Provincial Police have issued a warning about packages containing a lethal substance which have been shipped to homes across the province.

OPP say the packages contain sodium nitrite, and is being sold online and distributed by mail to those who are at risk of self harm.

It is a white crystalline substance, used as a food additive in processed meats, which if intentionally consumed in excessive amounts can reduce oxygen levels, impair breathing and result in death.

A disturbing element of the situation is those being shipped the packages, are at risk of self-harm.

Residents are being asked to remain vigilant and if they find a package from the following companies to immediately contact police:

  • Imtime Cuisine
  • AmbuCA
  • Academic /ACademic
  • Escape Mode / escMode
  • ICemac

Early Tuesday evening Peel Regional Police arrested a suspect believed to be responsible.

However, it is believed the packages have been shipped to more than a dozen Ontario communities and other parts of the world.