On May 8, 1858, Frank Leslie's Illustrated Newspaper published an exposé about a severe public health crisis in New York City: the milk circulating in local communities was contaminated with toxic distillery waste.

Known as "swill milk," the adulterated product was stripped of essential nutrients and laced with hazardous additives like chalk and plaster to make it look fresh and creamy. The exposé condemned local dairy producers, calling them “milk murderers,” for knowingly feeding already sickly cows the harmful byproduct and then distributing the tainted milk.

Infants became the greatest victims. “Malnourished babies were left vulnerable to illness and, in severe cases, death,” says Darin Detwiler, a food safety advisor, author and professor at Northeastern University featured in the documentary Poisoned. “Beyond lacking essential nutrients, the unsanitary and contaminated nature of swill milk exposed children to harmful bacteria and toxins, leading to high rates of foodborne illness.”

The New York Times reported: “Last year, swill-milk killed in this City alone—according to carefully-figured statistics—over 8,000 children!” The scandal angered the nation and triggered demands for reform.

“In the 1850s, the U.S. lacked formal food safety laws, leaving those responsible for selling adulterated, contaminated milk largely unpunished despite public outrage,” says Detwiler. “The main outcome was reputational damage rather than legal penalties, and while the scandal led to eventual changes like the adoption of pasteurization and dairy inspections, it lacked immediate enforcement or accountability.”

Louis Pasteur invented pasteurization in 1864 as a method to heat liquids and eliminate harmful bacteria, but it took decades for the process to become standard practice in the United States. The lack of pasteurization led to a wide variety of foodborne illness outbreaks.

In 1911, for example, Boston experienced a "septic sore throat" epidemic caused by Streptococcus bacteria in raw milk taken from cows with infected udders. The outbreak affected 1,400 people and claimed 48 lives. Other cities that grappled with septic sore throat epidemics in the early 1900s, included Baltimore, Chicago and Concord, New Hampshire.

Typhoid fever spread rapidly across the United States in the late 19th and early 20th centuries, caused by the Salmonella Typhi bacteria commonly spread through contaminated food and water. The most infamous case, “Typhoid Mary” Mallon, involved an asymptomatic cook who unknowingly infected at least 53 people, leading to three deaths. Her case drew urgent attention to the dangers of asymptomatic carriers and emphasized the need for stricter hygiene in food preparation.

During the winter of 1924-1925, when New York reigned as the nation's oyster capital, harvested oysters were stored in baskets submerged just below the waterline, dangerously close to untreated sewage outlets. This exposure allowed typhoid bacteria from the sewage to contaminate the oysters, which were then transported nationwide in refrigerated rail cars.

The resulting outbreak caused over 1,500 illnesses and claimed 150 lives, marking it the most deadly foodborne illness outbreak in U.S. history. The crisis prompted the creation of the National Shellfish Sanitation Program to standardize shellfish safety and prevent future outbreaks.

As canning became popular in the early 20th century, improperly canned foods often harbored Clostridium botulinum, leading to severe or fatal cases of botulism. The 1906 canned meat outbreaks exposed major issues with contaminated meat products. Upton Sinclair’s 1906 novel The Jungle further intensified awareness, vividly portraying unsanitary conditions in the meatpacking industry and the health risks of tainted products.

“[Sinclair’s] legacy endures as a pivotal force in the creation of food safety laws, cementing him as a pioneering advocate whose influence reshaped public health protections in America,” says Detwiler. Sinclair’s work, along with public pressure, spurred the passage of the Pure Food and Drug Act and the Meat Inspection Act that same year.

In 1985, a Listeria outbreak linked to Mexican-style soft cheeses from Jalisco Products, Inc., claimed 52 lives and sickened over 100 people, including many pregnant women. Listeria poses severe risks for pregnant individuals, often leading to miscarriages, stillbirths and serious neonatal infections. This outbreak further underscored the dangers of unpasteurized milk, a major contributor to the contamination, and prompted the FDA to enforce stricter pasteurization standards for soft cheeses.

In 1993, Jack in the Box, a fast-food restaurant chain, experienced a tragic foodborne illness outbreak. “Four toddlers, including my own son, died and approximately 200 people were hospitalized out of 732 cases, and many suffered long-term health complications,” says Detwiler. This outbreak was caused by undercooked beef patties contaminated with E. coli O157, a strain of bacteria particularly dangerous for young children and the elderly.

Following the tragedy, regulations were updated to require higher cooking temperatures for beef, and the outbreak spurred significant changes in food safety policies, including the establishment of Hazard Analysis Critical Control Points (HACCP) protocols.

An outbreak of Salmonella in peanut butter and peanut paste, originating from the Peanut Corporation of America (PCA), occurred in 2008 to 2009. The incident left over 700 people across 46 states ill and caused nine deaths. Investigators discovered unsanitary conditions at PCA’s processing plant in Blakely, Georgia, including the presence of rats, mold and leaking roofs. Even more concerning was the revelation that the company had knowingly shipped contaminated peanut butter. PCA later recalled over 3,600 peanut butter products, making it one of the nation’s largest food recalls.

The scandal resulted in criminal convictions and the permanent closure of the business operations. “This case was significant in setting a legal standard for accountability in food safety,” says Detwiler, which he describes in his book Food Safety: Past, Present, and Predictions. “The CEO received a 28-year prison sentence, the longest sentence handed down for a foodborne illness case in U.S. history.”

In 2011, an outbreak of Listeria monocytogenes traced to cantaloupes from Jensen Farms in Colorado became one of the deadliest foodborne illness outbreaks in recent U.S. history. The outbreak led to 33 deaths and one miscarriage, affecting people across 28 states.

Jensen Farms recalled over 300,000 cantaloupes due to Listeria contamination. “This remains one of the largest recalls in U.S. history in terms of volume and impact​,” explains Detwiler. Following the outbreak, many growers adopted stricter sanitation standards, and it highlighted the need for improved traceability in produce distribution.

The Boar’s Head deli meats outbreak, linked to Listeria contamination, resulted in 10 deaths and 59 reported illnesses across 19 states. Over 7 million pounds deli meat was recalled, sparking widespread concern about food safety in ready-to-eat products. The outbreak has led to increased scrutiny of processing standards and reinforced the importance of stringent safety protocols to prevent contamination in large-scale food production.

“The Boar's Head outbreak is a great concern, because the risk of Listeria in these types of products is well-known, and companies can take steps to mitigate the risk and prevent illnesses,” says Craig Hedberg, an epidemiologist and food safety expert at the University of Minnesota. “The failure to do this is a major breakdown.”

“There are many outbreaks that may be caused by organisms and contamination methods that are not as well characterized, so companies may not understand how to prevent them fully,” says Hedberg. “We like to say foodborne outbreaks are preventable, but food systems are constantly changing, and some things slip past our prevention measures.”