Detroit's pharmaceutical, medical and chemical industries are shown in the upper panels of the north and south walls. In the far right panel on the north wall, a child is being vaccinated in a medical laboratory surrounded by the animals whose blood is used to make serum and the scientists who make the serum into vaccine. In the far left panel, chemical bombs are being made, and in the panels beneath both of these scenes Rivera further contrasts the constructive and destructive results of science—a healthy human embryo (below the vaccination panel) and cells suffocated by poisonous gas (below the chemical bomb panel).

When the Detroit Industry murals were completed in March 1933, and the public was invited to view them, a controversy erupted. Though some people thought the subject of industry made the mural inappropriate for display in an art museum and others objected to Rivera's Marxist political views, it was this panel that became the focus of protest. Viewers were outraged at what they felt was Rivera's parody of a Nativity scene. The poses and draped clothing of the nurse and child as well as the halo-like cap and hair of the two figures echo traditional depictions of Mary and Jesus. In addition, the farm animals in the foreground recall a manger scene, while the three scientists were interpreted as the Three Wise Men. Members of the press, clergy, and the City Council demanded that the murals be whitewashed.

Through the efforts of the museum staff and Edsel Ford, as well as the support of the national art community and hundreds of Detroiters, the murals were saved. By the time the controversy had subsided in Detroit, Rivera had begun to work on a large mural project at Rockefeller Center, which was under construction in new York City. He strayed from the authorized theme and began using overt, anti-Capitalist references, including a portrait of the Soviet hero Vladimir Lenin. As a result, the Rockefeller Center murals were ordered destroyed before completion.

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