Three ways climate change can increase food-borne illnesses
As temperatures rise and extreme weather events become more common, scientists are warning of an increase in food-borne illnesses as a result.
Every year, approximately one in eight Canadians will become sick from a food-borne illness caused by bacteria such as salmonella, Listeria and E. coli, according to the Canadian Food Inspection Agency. Globally, the World Health Organization estimates that 600 million people will fall ill and 420,000 will die from contaminated food every year.
Lawrence Goodridge, a professor of food safety at the University of Guelph, said he predicts there will be more outbreaks of food-borne illnesses linked to climate change in the coming years.
“The one thing I found surprising is how fast we’re seeing food contamination events impacted by climate change,” Goodridge told CTV’s Your Morning on Friday.
Goodridge said there are three main climate change variables that can contribute to a rise in food-borne illnesses.
Hurricanes and other extreme rainfall events that result in flooding can have a significant impact on food safety, according to Goodridge. He explained that floodwater can contaminate fields by washing bacteria, such as salmonella, Listeria, and E. coli, onto crops.
“For example, last year Hurricane Florence impacted North Carolina and that led to flooding of lagoons where hog waste was kept and those lagoons overflowed, contaminating the fields where fruits and vegetables were grown,” he said.
Extreme weather events can also lead to power outages, and therefore, more food-borne illnesses because people can’t refrigerate their food.
Rising ocean temperatures
In addition to extreme weather events, Goodridge said rising ocean temperatures can harm certain foods because warmer water allows certain bacteria to grow. He said Vibrio parahaemolyticus, the most common bacteria found in B.C. waters, thrive in warm seawater and contaminate food, such as mussels and oysters.
People can be exposed to Vibrio parahaemolyticus if they eat raw or undercooked shellfish.
Rising air temperatures
Just like the oceans, rising air temperatures can also result in more incidences of food-borne illness, according to Goodridge. He said bacteria that sicken people, such as salmonella, Listeria, and E. coli, grow much better in warmer conditions.
“[It’s] one reason why we refrigerate our food,” he explained. “Many scientific studies have found that, as the ambient air temperature increases, these bacteria can cause more illnesses.”
For example, Goodridge cited a study conducted by the Public Health Agency of Canada that showed for every one degree rise in the ambient air temperature, the number of people who became sick with E. coli increased by six per cent.
Goodridge said people can protect themselves from food-borne illnesses by safely handling and thoroughly cooking their food. If there is a power outage, he said people shouldn’t open their fridges because foods of animal origin can be safe to eat for up to four hours.