December 15, 2006:
Health Canada has set maximum acceptable concentrations (MACs) for most contaminants in farm and ranch water bodies and aesthetic objectives (AOs) for others. The MAC for nitrate, for example, is 10 mg per litre for human consumption and 100 mg per litre for animals, says Ken Williamson, a water specialist with Alberta Agriculture and Food (AAF).
The AO for sulphate, which can act as a laxative to humans and livestock in high concentrations, is less than 500 mg per litre. Other AOs deal primarily with nuisance issues. "Iron within reasonable levels, for example, isn't going to do a person any harm, but it can cause nuisance problems such as staining laundry," says Williamson.
To read our article "How safe is the water you drink?" on farm water testing, click here.