Today I learned about how much danger there was in food everywhere during the Victorian era of England. Some of these horror stories I had heard before. I am familiar with a lot of practices back in the day that killed people like putting borax (detergent) in spoiled milk and thinking it would make it safe to drink, when in reality it would just kill children who drank it, and not the bacteria, and left the poor kids who survived susceptible to bovine tuberculosis transmitted from the rotten milk because this was a time before pasteurization.
However, there was still a lot of information that was brand new to me, and it was especially sad because often in these situations it wasn't just ignorance, but greedy merchants selling things they were well aware weren't good for people to eat, but doing it anyway to maximize profit-- something that still resonates today in the 21st century.
I learned from my reading that bakers and millers would put chalk, sand, sawdust, plaster of Paris and alum was in bread as a cheap filler in place of actual flour. Alum was used in particular because it made the bread look white and pretty, and retained water so the loaves would feel substantial, when you were really eatting a muth full of nothing. This could result in all sorts of digestive problems and even mean death from malnutrition over time.
Something else new to me was that just about anything from used tea leaves to dust, ashes to iron filings and sheep dung would be passed off as black tea by unscrupulous merchants. Lead chromate was added to mustard to cut costs so that it would look yellow without the real mustard seeds or tumeric. One of the worst to read about strchynine being put into beer to hide when it had been watered down, which could mean hallucinations and violent death. Yikes!