Remember that "risk" is not just used for
damage to health & environment. It also
includes risk about money, image etc. So
we now need to include these elements.

As stated previously, risk comes in a package. So, too, does risk assessment. There are not neat calculations for all environmental impacts.

People's perceptions also play their part.

DEFRA Guidelines on Social Aspects of RIsk

But where do people's perceptions come from? Why are people more concerned about some risks than others?

They get their concerns from others and from the popular press.

Concerns about salmonella in eggs or pesticide in food are often generated by stories in the press.

They cause people to change habits for a while, although many revert back when the stories die down.