Newfoundland and Labrador's transportation minister says a controversial roadside herbicide spraying program is necessary to keep highways safe, with the chemicals no more dangerous than salt.

But critics disagree, saying the province should stop using chemicals to prevent vegetation growth near roads.

Transportation Minister Tom Hedderson called a news conference Thursday afternoon to respond to what he called misinformation about the spraying program.

"We do need to use it for our roadside simply because it's the most effective right now, it's the safest, and it gives us the best results," Hedderson told reporters.

"The bottom line is that I have people travelling on the highway now that are safer."

The minister said the spraying is vital to help prevent moose-vehicle collisions.

Hedderson has come under fire for suggesting that the chemicals used in spraying programs are no more dangerous than salt.

He repeated that again Thursday.

'Toxic' chemicals

But NDP environment critic George Murphy said Hedderson is wrong, and the province should stop using Tordon 101.

One of the chemicals used by the provincial program — called 2,4-D —  was recently banned for cosmetic use in Newfoundland and Labrador.

But the government is still using the product.

"This stuff is toxic; we really don't need it," Murphy said.

Murphy suggested traditional methods — such as brush cutting along the sides of highways — should be used.

Dr. Ian Simpson, a physician in western Newfoundland who is with the Coalition for Alternatives to Pesticides, agrees.

'I am horrified. I really am shocked.' —Dr. Ian Simpson

He also says machinery and manpower should be used instead of chemicals.

"I am horrified," Simpson said. "I really am shocked."

Simpson says Hedderson's comments equating the chemicals to salt are perplexing.

"Common sense says that if the regulations that Dow Chemical put on this particular chemical state — don't get it on the hands, don't get it on the skin, don't breathe it in, don't get it in the eyes, use a ventilator, use a mask — and we have a minister of the Crown saying it is as harmless as table salt and vitamin A ...

"There is a disconnect here."

A group that represents lawn-care professionals is also unhappy with the minister.

Landscape Newfoundland and Labrador is upset that Hedderson said the ban on the chemical wasn't put in place for health reasons, but because they were being used indiscriminately.

The group says any suggestion that its members were using chemicals dangerously is wrong.