Upton shocking novel sparked an investigation that led to..?

You're likely thinking of Upton Sinclair's novel "The Jungle" (1906). This book, a fictionalized account of the horrors of the Chicago meatpacking industry, sparked a public outcry and led to the passage of two landmark pieces of legislation:

* The Meat Inspection Act of 1906: This act mandated federal inspection of meatpacking plants to ensure safe and sanitary conditions.

* The Pure Food and Drug Act of 1906: This act banned the sale of adulterated or mislabeled food and drugs, leading to the creation of the Food and Drug Administration (FDA).

So, the investigation that "The Jungle" sparked resulted in better sanitation standards in the meatpacking industry and the establishment of a regulatory body to protect consumers from unsafe food and drugs.