The food we eat can pose a wide range of environmental health threats if it is contaminated with chemicals or dangerous microorganisms.
Biological threats include bacteria such as listeria and salmonella, and viruses such as norovirus.
These can enter the body in contaminated food and cause disease that can be extremely uncomfortable, and in some cases life-threatening – especially for vulnerable groups such as the very old or very young.
Other harmful microorganisms include bacteria and fungi that produce toxins that can linger on food. A famous example is aflatoxin, which is produced by a mold and is often found on peanuts.
People can also be infected by larger parasites, including worms and single-celled organisms such as Giardia, through the food they eat.
Food poisoning with a biological origin is usually the result of poor hygiene or improper handling, preparation and storage of food.
A single source of contamination tends to affect only a small number of people but in some cases tens or even hundreds of thousands can be made ill by the same source of contamination.
In poorer countries, unclean water is also major source of food poisoning.
Often these contaminants are present because of poor standards, or accidental contamination. In 1998, pigs in Ireland ate feed that had been contaminated with dioxins. When the dioxins were detected in the meat, governments ordered a recall of pork products and this had major economic impacts throughout the supply chain.
Sometimes hazardous chemicals have been added to food on purpose (see case study). Examples include drugs, food colourants and pesticides that have been banned or severely restricted but which enter the food chain because of unscrupulous business practices or weak enforcement of regulations.
Some harmful food contaminants have only recently been identified as potential threats. An example is acrylamide, which forms in some foods such as potatoes are cooked when they are heated.
This was only discovered in 2002 and led to immediate concerns as exposure to other sources of acrylamide is known to pose health threats. Research is underway to assess what level of risk is posed by acrylamide that forms during food production.
ALTERNATIVES / SOLUTIONS
At the simplest level, moves to ensure food safety include basic good hygiene before, during, and after food preparation and consumption. This includes hand washing, cooking food properly, storing it safely (in a refrigerator) and eating it quickly.
Some countries have strict regulations that make it easy to trace any food back to its source. This puts pressure on food producers to adopt high standards of hygiene, but also raises the costs to consumers.
The Codex Alimentarius is a UN-backed collection of internationally recognized standards, codes of practice and other recommendations about food safety.
The texts are compiled by a body set up by the World Health Organization and the Food and Agriculture Organization of the United Nations.
The Codex guidelines are presented as voluntary standards that countries can choose to adopt. But because the World Trade Organization makes use of them when it settles trade disputes, some countries and corporations fear that the guidelines could become a mandatory standard that will be expensive to meet.
Most cases of food poisoning are isolated and affect only a small number of people, but when a large outbreak occurs journalists have an important role to play in reporting on the threat and its cause.
For other types of threat, such as chemical, health problems might take years to develop.
A great source of information for journalists is the World Health Organization (WHO). This website gathers WHO information on food safety publications, meetings and training materials.
For more tips, visit the website of the 2009 World Conference of Science Journalists. It had a session devoted to reporting food safety and related issues, and you can listen to audio files and view powerpoint presentations.
Food is a multi-billion dollar business so journalists should take care to check whether their sources have hidden links to the industry.
Many websites, for instance, appear to be independent sources of information on food safety, but in fact are staffed by people with strong links to major food producers.
An example of high-profile journalism on food safety is this article by New York Times journalist Michael Moss, which won the Pulitzer Prize in 2010.
CASE STUDY – Melamine in China’s milk supply
One of the most high profile of food safety scares in recent years took place in China, where food manufacturers had added a chemical called melamine to milk and baby formula to make the products appear to contain more protein than they actually did.
Melamine is normally used to make plastics and is known to be dangerous to human and animal health as it can react with cyanuric acid in the body and cause kidney disease.
In 2008, close to 300,000 babies became ill after consuming contaminated products. Hundreds were hospitalized and six died.
One company was largely responsible, but when Chinese authorities investigated they found that 21 other companies had been adulterating their dairy products.
China had banned the use of melamine in foods one year earlier, after the United States detected melamine in pet food that contained protein from China.
The scandal had major economic impacts too as it led 11 nations to ban imports of Chinese dairy products.