Railroad ties are treated with chemical preservatives to protect them against insect pests and decay, which can extend their service life to 30 years or more. The most common preservative used is creosote, an oil-based pesticide that is applied to the wood. Creosote is a wood preservative pesticide used in outdoor settings such as in railroad ties and utility poles. Other preservatives approved by the EPA can also be used to treat wood, including copper naphthenate or copper naphthenate-borate.
It is important to note that creosote-treated wood can pose risks to fish and invertebrates when used in aquatic and railroad structures. Additionally, creosote and chromated copper arsenate, another chemical preservative used in railroad ties, are banned for residential use due to their potential health risks. If homeowners need to dispose of creosote-treated wood, it can usually be taken to a landfill that accepts hazardous waste.
