Dirty, dangerous and demeaning

"Dirty, Dangerous and Demeaning" (often "Dirty, Dangerous and Demanding" or "Dirty, Dangerous and Difficult"), also known as the 3Ds, is an American neologism derived from the Asian concept, and refers to certain kinds of labor often performed by unionized blue-collar workers.

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

Any task, regardless of industry, can qualify as a 3Ds job. These jobs can bring higher wages due to a shortage of willing qualified individuals and in many world regions are filled by migrant workers looking for higher wages.

Traditionally, workers in 3D professions are well paid, due to the undesirability of the work, and the resulting need to pay higher wages to attract workers. This has allowed the uneducated and unskilled to earn a living wage by foregoing comfort, personal safety and social status. This concept proves itself in the economic theory of quantity supplied and quantity demanded (see Quantity adjustment), the wages paid to these workers is higher due to the undesirable nature of their professions.

However, in regions where certain classes of workers are restricted to this type of work or there are contributing regional conditions - for example, high unemployment, adjacent to regions with high poverty, or the recipient of driven labor migration - there will be workers willing to accept lower than equilibrium wages and then these jobs are not well paid. Large scale international labor migration, from developing to developed countries since the late 19th century and early 20th century has provided a pool of migrants willing to undertake employment for lower wages than native residents. Higher wages in developed countries are a strong 'pull' factor in international migration, and thus while a migrant worker is willing to accept a comparatively low-wage for a 3D job in a developed country it may mean a significant increase in wages compared to their originating country.

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