I've also been told that the railways used arsenic as a weed killer and would spray between the rails and the ballast as well for many years before the days of caring for environment came to be.
Could be something to it, a quick google and :
"Arsenic is used as a pesticide primarily to preserve wood from rot and decay. In the past, arsenic was also used in rat poisons, ant poisons and
weed killers. Old agricultural soils may contain high levels of arsenic resulting from its former agricultural uses. Airborne arsenic particles can be inhaled and they can travel long distances in the air. Most forms of arsenic tend to stick to soil or sediment particles but some can dissolve in water, possibly leaching into lakes, rivers, or ground water. Burning, sawing or sanding arsenic-treated wood can increase the chance of inhaling arsenic. Long-term exposure to arsenic can increase the risk of cancer over a lifetime. Most arsenic compounds are not well absorbed by the skin so only small amounts are likely to get into your body through your skin."
However, on saying this , would I have a fire with railway sleepers?? hell yes!!! Life's too short and you probably do more damage to your body drinking coke
( or the stuff you drink with coke)
