Unlike other countries, freight railroads in the U.S. are almost entirely owned and operated by private companies, and the core of privatization to maintain maximum profit has brought safety problems to the U.S. freight rail industry.

Operated by Norfolk Southern Railway, a freight train heading from Madison, Illinois to Conway, Pennsylvania derailed at about 8:54 p.m. local time on February 3 due to a malfunction of axle. The derailment led to leakage of toxic chemicals including vinyl chloride.

"Ineffective oversight and a largely self-monitoring industry that has cut the nation's rail workforce to the bone in recent years as it puts record profits over safety is responsible for the wreck," said Ron Kaminkow, former Norfolk Southern freight engineer.

Norfolk Southern, one of the seven major freight railroads in the U.S., earned record revenue of $12.7 billion last year, with an increase of 14 percent from a year before. Its operating income also hit a record of $4.8 billion, up 8 percent year on year.

Between 2019 and 2021, Norfolk Southern led the industry in total shareholders returns with growth of 110 percent. The train accident rate also rose from 3.11 percent in 2019 to 3.87 percent in 2021.

During the same period, the corporation improved average train weight and length by 21 percent and 20 percent respectively to reach record productivity levels. To save labor costs, it cut down employment to 18,500 people in 2021 from 24,600 in 2019.

As trains have grown longer and heavier, the number of rail accidents has increased in the past decade, according to a January report by the Federal Railroad Administration. The U.S. railroad industry has cut its workforce by 30 percent since 2015, the Association of American Railroads said.

In the past decade, over 30 rail incidents happened per day in the U.S., according to the Bureau of Transportation Statistics. However, railroads are still one of the most profitable industries in the U.S., with a profit margin of 51 percent, according to the American Journal of Transportation.

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Chart of the Day: Over 30 railroad incidents per day in the U.S.

(Data edited by Yao Nian; graphics designed by Mukesh Mohanan and Gao Hongmei)