The largest group of deaths attributable to overwork came in the transportation and postal industries in fiscal 2016, with 41 people, or 21.5 percent, according to the nation's second white paper on "karoshi."

The 2017 white paper on measures to prevent karoshi, released by the health ministry on Oct. 6, focuses on the transportation industry, which is suffering from a severe labor shortage.

It found that respondents to a survey reported being made to work longer overtime hours during the busy year-end holiday season.

“To prevent karoshi, it will be effective to reduce working hours in December and make the gap with less busy months smaller,” the white paper recommends.

The white paper describes the industry’s conditions that could contribute to death by overwork.

It marked the second white paper on karoshi since the Ministry of Health, Labor and Welfare published the first in 2016. The latest totals 380 pages, up 100 from the 2016 edition.

“We used four of those pages to describe the fact that the suicide of a rookie employee of (advertising giant) Dentsu Inc. (in 2015) led to strengthening of measures to prevent karoshi, though we did not name her,” said a ministry official in charge of the paper.

In fiscal 2016, which ended in March 2017, deaths and suicides, including attempted ones, of 191 people were recognized by labor standards inspection offices as resulting from overwork. The number was up two from fiscal 2015.

The number of recognized karoshi cases in the manufacturing industries was 35 and 23 in the construction industry.

In the industries that had many karoshi cases, long working hours were also conspicuous.

In particular, one out of five workers was working more than 20 hours of overtime per week in the transportation and postal industries.

The white paper also describes the working conditions in the transportation industry.

From December 2016 to February 2017, the ministry conducted a survey of about 40,000 drivers of buses, taxis and trucks. Of these, 4,678 replied to a questionnaire. Asked the reasons for their overtime, about 30 percent cited a “labor shortage.”

Many of the respondents also said that their overtime work at midnight or on holidays frequently occur in December when shipments and deliveries of goods and moves of passengers are concentrated. Therefore, the drivers often suffer from diseases that labor standards inspection offices recognize as caused by overwork in the period from January to March.

Lawyer Hiroshi Kawahito, who serves as the secretary-general of the National Defense Counsel for Victims of Karoshi, said, “It is necessary to strengthen regulations on working hours of drivers. But in the government’s reform on how to work, the application of the upper limit on overtime will be postponed for five years in the transportation industry. We can easily imagine that drivers will die (of overwork) during the period. It is a problem.”

(This article was written by Yoichi Yonetani and Koichi Murakami.)