On April 16, 2015, Health Canada posted Guidelines for Canadian Drinking Water Quality - Guideline Technical Document: Toluene, Ethylbenzene and Xylenes.

Toluene, ethylbenzene and xylenes are primarily synthetic chemicals found in petroleum hydrocarbons, such as gasoline and diesel fuel, or used as industrial solvents or as intermediates in styrene or benzene production. They can enter drinking water through leaching from contaminated sites or from industrial discharges of chemical manufacturing plants, or as a result of a spill during transportation or storage.

The guidelines set maximum acceptable concentrations, as follows: 0.06 mg/L (60 µg/L) for toluene, 0.14 mg/L (140 µg/L) for ethylbenzene, and 0.09 mg/L (90 µg/L) for xylenes.