EPA determines formaldehyde poses an 'unreasonable risk' to humans and must be regulated

[IcyPeas]

19. Formaldehyde was used in milk in the 1890s (Smithsonian article - infants died)

The 19th-Century Fight Against Bacteria-Ridden Milk Preserved With Embalming Fluid
….
Finally, if the milk was threatening to sour, dairymen added formaldehyde, an embalming compound long used by funeral parlors, to stop the decomposition, also relying on its slightly sweet taste to improve the flavor. In the late 1890s, formaldehyde was so widely used by the dairy and meat-packing industries that outbreaks of illnesses related to the preservative were routinely described by newspapers as “embalmed meat” or “embalmed milk” scandals.

… the dairy industry to deal with milk’s bacterial problems simply by dumping formaldehyde into the mix. And although Hurty would later become a passionate advocate of pasteurization, at first he endorsed the idea of chemical preservatives.

In 1896, desperately concerned about diseases linked to pathogens in milk, he even endorsed formaldehyde as a good preservative. The recommended dose of two drops of formalin (a mix of 40 percent formaldehyde and 60 percent water) could preserve a pint of milk for several days. It was a tiny amount, Hurty said, and he thought it might make the product safer.

In the summer of 1900, The Indianapolis News reported on the deaths of three infants in the city’s orphanage due to formaldehyde poisoning. A further investigation indicated that at least 30 children had died two years prior due to use of the preservative, and in 1901, Hurty himself referenced the deaths of more than 400 children due to a combination of formaldehyde, dirt, and bacteria in milk.

This article is very interesting:

https://www.smithsonianmag.com/science-nature/19th-century-fight-bacteria-ridden-milk-embalming-fluid-180970473/