Sleepers are treated with a black substance called creosote for preservation purposes. Creosote contains chemicals, and the creosote used in the United States results from heating the coal by-product coke. Exposure to creosote could be hazardous and create skin irritations and, in extreme cases, even cancer. If you plan to work with sleepers treated with creosote, remove it using one of a few possible natural methods.
Some of the chemicals that make up creosote dissolve in water. If exposed to adequate moisture levels, these chemicals will leach away into the soil. If the groundwater in your area is not deep, however, you face the risk of the chemicals from the creosote seeping into the groundwater.
Another way to get rid of creosote from sleepers involves using a solvent, whether in the form of white spirit or a paint thinner. Use this solvent to rub the creosote away.
If you plan to use sleepers for landscaping projects, you will likely be exposed to creosote and should take some safety measures. Wear gloves and long-sleeved outfits when you have to handle wood treated with creosote. Also, work in well-ventilated areas. Do not work in hot areas, which may activate the creosote vapours. Avoid exposing children to the sleepers since they might get the creosote on their skin or clothing and could swallow it. If the landscaping is for a garden that grows vegetables, do not use sleepers. The creosote compounds may contact the roots of the vegetables, producing vegetables that expose you to creosote.