BBC News | August 2023
Shoppers in the UK are being reminded to thoroughly wash mixed salad leaves, amid concern that this food could be the source of a major outbreak of food poisoning that has killed two and infected more than 150 people in the country.
The infection – the E. coli O157 bug - can cause bloody diarrhoea and abdominal pain.
The World Health Organization (WHO) estimates that up to 600 million people fall ill and 420,000 die every year from eating contaminated food, so watching what you eat is a worldwide concern.
With this in mind, the BBC spoke to food safety expert Bill Marler, a lawyer who has been involved in practically every major food poisoning case in the United States over the last few decades.
Here’s what he does and doesn’t eat.
Unpasteurised milk and packaged juices
Bill Marler’s experience in litigation has led him to swear off raw or unpasteurised milk products or unpasteurised juices. The danger is that there can be severe complications due to ingesting a bacteria known as E. coli, which can lead to acute kidney failure, perhaps necessitating a kidney transplant.
Neither does Mr Marler eat raw sprouts such as alfalfa, mung bean, clover or bean sprouts. These have been linked to some of the largest foodborne outbreaks in the world. In 2011, an outbreak linked to fenugreek seeds in Germany meant up to 900 people developed kidney failure and there were more than 50 deaths. According to Mr Marler, in the US and Canada there have been 50 sprout outbreaks in the last decade and a half.
Meat that isn’t well done
With ground or minced meat, any bacteria that is on the surface of the meat has been mixed into the interior. That’s why it’s important to cook hamburgers thoroughly.
When it comes to steaks, there’s typically less danger as the bacteria on the outside is killed during the cooking process. But, warns Mr Marler, a lot of steaks in restaurants get needle-tenderised – poked with needles to make the steak less tough - and that pushes any bacteria into the interior. If that’s the case, he warns that the steak needs to be cooked just like a hamburger.
Pre-washed and pre-cooked fruits and vegetables
In 2006 there was a major outbreak of E. coli linked to spinach – more than 200 people were made sick and up to five people killed by the outbreak in the US. Mr Marler says he represented most of those involved. The bacterial contamination was eventually linked to a spinach farm in California that had had some animal intrusion, and the faeces had contaminated the spinach with E. coli. When it was cut and sent to a facility where they triple washed it, that bacteria was spread amongst the product and shipped across the country, and sickening many.
Raw and undercooked eggs
In 1988, a UK health minister sparked a crisis when she said that most of the country's egg production was infected by salmonella. Egg sales fell by 60%, she was forced to resign and the government ordered the slaughter of more than two million chickens.
A recent report by a British food safety group says that pregnant women should be told they can safely eat runny eggs, almost 30 years after a salmonella crisis. But, whilst he agrees that it’s true that raw eggs are safer today than they were before, Bill Marler still urges caution. He thinks that federal legislation about egg safety has helped, but salmonella still poses an unacceptable risk to consumers of raw or undercooked eggs.
Raw oysters and other raw shellfish
The risk from oysters and other raw shellfish is that they are filter-feeders. That means if there is a bacterial or viral infection in the water, it’ll get into the food chain easily. And Bill Marler thinks that the problem is being exacerbated by global warming.
“I’m from Seattle and some of the best oysters in the world come from the Pacific north-west, but there are clearly issues going on with our water quality and the temperature. It’s a new risk factor which you have to think about when you are ordering those raw oysters,” he says.
Mr Marler warns that the age of the sandwich is the major risk factor, which could lead to exposure to listeria montocytogenes – a very nasty bug. He says it is a big killer both in the US and around the world and will put nearly everyone who ingests it in the hospital.
“Listeria grows really well at refrigerator temperatures, so if somebody makes you a sandwich and you eat it nearly immediately, the risk of listeria is low. If they make it and it’s stored in a fridge for a week before you eat it, it’ll give the listeria bug a chance to grow to a sufficient quantity that it’ll make you sick,” he says.
But one food type that people are frequently sceptical about – sushi – holds few fears for Bill Marler, although he concedes that you should be careful where you buy it.
“A good sushi restaurant is something that I go to. I don’t buy sushi from a grocery store or a gas station. A good sushi restaurant is pretty safe as fish are low risk when it comes to bacterial infections. More often I’ll go to a sushi restaurant before I go to a steak place. It’s a risk profile I feel more comfortable with,” he says.