MISSISSAUGA, Ontario - Imports of phthalo green, a very popular ink in the packaging and printing business, have been halted because of trace levels of the banned chemical hexachlorobenzene (HCB), according to the Canadian Plastics Industry Association.

Pigment manufacturers say the ink contains residual HCB levels that exceed the allowable limit of 20 parts per billion set out in the Prohibition of Certain Toxic Substances Regulation, 2003 (SOR/203-99), made under the federal Canadian Environmental Protection Act, 1999.

"Phthalo green is used in printing inks, house paints and automotive paints," says Barrie Porteous, the marketing manager for liquid inks at Sun Chemical Limited. "It's a very clean and permanent green, used to print a lot of corporate logos and even the Canadian $20 bill. There's really no other substitute for it."

While it's illegal to bring the ink into Canada under the current regulations, a package of proposed amendments would allow for greater variation in the controls placed on individual substances. "It may or may not be okay to use phthalo green down the road," says Porteous.