Dirty, dangerous and demeaning

The term originated from the Japanese expression 3K: kitanai, kiken, kitsui[1] (respectively 汚い "dirty", 危険 "dangerous", きつい "demanding"), and has subsequently gained widespread use, particularly regarding labor done by migrant workers and burakumin.

[7][8] This has allowed the uneducated and unskilled to earn a living wage by foregoing comfort, personal safety and social status.

In the United States, 3D occupations once filled by Irish and German immigrants, are today held by many Latin Americans.

Regardless of the hazards, engaging in high risk, low status work can be a way to escape poverty - captured by a line in the Irish folk song Finnegan's Wake, "to rise in the world he carried a hod."

[16] There is often a risk of early retirement due to injury, general joint depletion or mental fatigue.