Introduction
The presence of lead (Pb) in foods can be hazardous to human health. It can produce subtle but adverse long term health effects, particularly in children. Lead residues can be found in maple products, especially when produced with lead containing equipment.
According to Health Canada, the presence of lead in maple syrup, at levels of 0.5 parts per million (ppm) or more, suggests that avoidable contamination has taken place. Lead levels for other maple products have not yet been established.
Avoid, reduce or eliminate lead in maple products
Sources of lead include equipment:
- welded with lead solder (soldered before 1995, especially in storage tanks and homemade equipment)
- made from galvanized steel before 1994
- with brass and bronze joints and connections
- with terne plate, a lead containing alloy
It has been reported that a significant portion of the lead is concentrated in the sugar sand suspended in the syrup, even if a large percentage is in a dissolved form. Therefore, filtration systems such as gravity filtration and press filtration may reduce lead levels in maple syrup. A laboratory analysis would confirm whether the residue level was successfully reduced below 0.5 ppm.
To help identify, reduce and eliminate possible sources of lead contamination, numerous resources can be used, including:
- Maple Syrup Fact sheet No. 211b1094(E): A few rules to reduce the risks of contamination of maple syrup products by lead residues, Centre ACER, December 1999.
- Keeping Lead Out of Maple Syrup, Proctor Maple Research Center, University of Vermont, with the assistance of the US Department of Agriculture (USDA) and the North American Maple Syrup Council (NAMSC).
- Local maple producers' associations.