The train that derailed Thursday morning in west-central Minnesota — leading to the evacuation of the town of Raymond — was carrying ethanol and corn syrup.

Q: What is corn ethanol?

A: Ethanol is a byproduct of corn that can be used in everything from fuels to medicines to paint. In the U.S. since the 1980s, ethanol has increasingly been blended with gasoline as fuel for motor vehicles. Proponents say the domestically produced fuel is superior to petroleum as it's a cleaner-burning fuel than conventional gasoline and can be grown domestically. However, critics have increasingly cited emissions at ethanol plants as counterbalancing environmental benefits.

Q: How is ethanol transported across the country?

A: Between 60% and 70% of ethanol is carried by rail, according to the Association of American Railroads (AAR), often to and from processing and refining facilities. As ethanol is derived from corn, and corn is grown in rural croplands, as much as 20% of corn ethanol freight first moves on short line and regional railroads, according to the AAR.

Q: Has ethanol spilled from trains before in Minnesota?

A: Yes. Most recently, in 2015, a BNSF train leaked roughly 20,000 gallons of ethanol into the Mississippi River after a derailment near Alma, Wis. At the time, BNSF said a full tank car holds 30,000 gallons.

Q: How often do trains derail in Minnesota?

A: Last year, Minnesota reported 34 train incidents. Derailments of trains carrying hazardous material, however, is relatively rare. More than 99% of hazmat trains safely reach their destinations, according to the AAR. Since 1975, 20 train accidents requiring evacuations of nearby residents have occurred in Minnesota, according to the Federal Railroad Administration. The last came in 2016 following a propane spill outside the southern Minnesota town of Ellendale.

Q: What train derailed in Raymond?

A: Thursday's derailment involved a train on a BNSF rail line. Chicago-based ADM, an agribusiness giant, confirmed on Thursday that the derailed train carried products made at ADM's corn processing facility in Marshall, Minn., more than 50 miles southwest of Raymond.

Q: How big was the derailment in Raymond?

A: The derailment overnight involved 22 cars carrying mixed freight, including ethanol and corn syrup. Four cars were reported on fire, according to BNSF.

Q: What is the health risk to nearby residents?

A: Ethanol is considered a hazardous material, according to the AAR. However, the U.S. Energy Information Administration says pure ethanol that is spilled will break down into "harmless substances." Fuel ethanol, however, is flammable and not drinkable, as the industry often mixes natural gas or gasoline into ethanol tankers to discourage human consumption. A spokeswoman for the Minnesota Pollution Control Agency said when ethanol reaches surface water, it can cause fish kills.

Q: How safe are ethanol tankers?

A: A transportation law signed by President Barack Obama in 2015 called the FAST Act spawned new regulations, requiring tankers — including train cars carrying ethanol — to be retrofitted or upgraded to DOT-117 models, which feature an array of safety features. An ADM spokeswoman confirmed all the company's tankers have been upgraded.

Q: How much Minnesota corn goes into ethanol?

A: According to an industry group, nearly 1 out of every 3 rows of corn grown in Minnesota ends up in ethanol (just less than 30%).

Q: How much ethanol does Minnesota produce?

A: There are 19 ethanol plants in Minnesota, according to the state's Agriculture Department. The highest concentration of processing facilities is in southwestern Minnesota. Nationwide, Minnesota ranks as the sixth-largest ethanol-producing state, generating 1.4 billion gallons in 2022. The top five states are all concentrated in the Midwest, with Iowa the biggest.