Gov. Eliot Spitzer last week signed a partial ban on a toxic wood preservative, creating a law that his predecessor had vetoed.

The law will partially end the manufacture, sale and use of creosote, a mixture of chemicals derived by high-temperature treatment of coal, tar or wood. The bill, however, left open the use of the preservative in cases where there is no alternative. The ban also does not affect the largest users of creosote: railroads, utilities and public authorities. 

"This is a smart bill, a bill that is designed to exempt from the prohibition on the use of creosote, the production of creosote, those few products where it's absolutely necessary and essential, so it will not have a significant impact on commerce," Spitzer said in a statement.