The possible dangers of mobile phones, controversy over genetically modified foods, fears over levels of radon gas, the dread of BSE and its human equivalent, variant CJD - all stories that involve the reporting of risk.
These scientific topics evoke strong public concerns, so understanding the risk aspect of these issues is crucial. By increasing understanding, a more informed public is better equipped to question and participate in a government's science policy.
Risk, however, is not an easy concept to communicate. There are two central ideas - risk and hazard - which are often viewed as the same. This confusion can create contradictions between different reports and sources. A hazard is something which endangers people, risk is the chance of exposure to that hazard. For example: eating salmonella-infected chicken is a definite hazard - you will get sick - but the risk of encountering it is low (unless the chef is careless).
The measurement of risk by scientists is a complex statistical process and produces results that are largely meaningless to the average person. Dr Wayne Anderson, chief specialist in food science with the Food Safety Authority of Ireland, says "scientists are trained to look at things in black and white, assessing them in strictly scientific terms". The public, on the other hand, focus more on their feelings. They want to know if they are safe or not. And because risk can only be communicated in terms of chance, it is a difficult message to get across.
Different people view risk in different ways. A person's views of a risk are affected by both factors in the wider society and psychological factors.
One especially relevant psychological factor when people view the risks of BSE and variant CJD is what Anderson calls "the dread factor". A degenerative brain disease arouses more dread than a heart attack, which is often perceived as an instantaneous death, he said. In addition, people underestimate common risks (smoking) and over-estimate exotic risks (CJD). People feel there is less risk of danger if they feel they can control their exposure to the risk. This is why some people have a fear of flying, but not of driving, despite there being a far greater statistical chance of dying in a car accident.
People also view risks as more worrying if they are involuntary (pollution), inescapable (pollution), coming from unfamiliar sources (your genes), causing hidden and irreversible damage (CJD) and posing a danger to future generations (radioactive waste). For a company or a government who wants to communicate risk, there are important areas to be aware of. According to Anderson, the first is trust - do the public trust who is giving the message? Credibility is the most important factor in communicating risk. People do not generally trust the pronouncements of politicians, who say, for example, beef is safe from BSE and are seen feeding it to their children, says Anderson.
He explains how people will be more likely to accept a risk if there are benefits. "Enough research exists to show mobile phones have possible adverse health effects, but people still buy them - because there are enormous benefits."
For genetically modified organisms (GMOs), on the other hand, the benefits are for the farmer, not the public - one reason for the level of opposition to them.
An organisation must also try to ensure they are open about their business. The Food Safety Authority in Britain, for example, held one of their most important meetings in public.
But the debate on GMOs has ethical, social and environmental aspects. And it is difficult to get one organisation to speak with authority on all of these issues.
Once people view something as a risk, it deserves to be reported by journalists, no matter if the risk is minimal, says Brian Trench, senior lecturer in communications at Dublin City University.
Because the risk is often very small, some reporters may feel lots of news coverage is unwarranted. A story about possible risk often becomes a story about a controversy. For example, coverage of the locating of a mobile phone mast in a given area will often switch its focus from the possible dangers associated with such masts to the positions of the company and local interest groups. And controversy is something journalists look for in stories.
A topic which has been under-reported until recently is the level of radon gas in schools and homes, says Trench. It illustrates some aspects of public perceptions of risk.
A naturally-occurring gas, radon can seep into a building where it can reach high levels. Living for a lifetime in a house with the maximum recommended level for radon could mean a 3 to 5 per cent chance of developing lung cancer. Naturally, this evokes fears. But compared with the high risk of developing lung cancer from smoking, the risk of contracting the disease from radon is small. Statistics back up this view. Smoking causes 90 per cent of all cases of lung cancer - 5 per cent of cases are estimated to be caused by radon. Yet people are often more worried about radon.
How, then, can the risk be communicated?
One method is through the use of comparisons, but the effectiveness of this method is debated, and some types of comparisons are far better than others. Saying smokers are X times more likely to contract lung cancer than non-smokers is better than comparing the chances of dying from smoking and dying in a car crash.
Trench says these comparisons may not necessarily reassure people, but in the future it may be possible to compile a scale to communicate a risk more accurately.
