It would have been worth quoting from this article, since it shows what nonsense the original claim about Sweden was.

"When Stockholm, Sweden introduced a "congestion tax" to discourage driving in the center of town, traffic eased and the pollution level dropped by between 5 and 10 percent.

There was one other result that was unexpected, but welcome nonetheless: The rate of asthma attacks among local children decreased by nearly 50 percent, according to a Johns Hopkins University economist's study of the tax and its impact."