Before a probit function is included in the calculation method, a step-by-step process of derivation, evaluation and formalisation is followed.

The government has laid down rules in the regulation on animal feeds to guarantee the quality of animal feeds, and thus also of meat, milk and eggs. Many of the legal requirements for producers and those who distribute animal feeds are set at the European level.

The Product Board Animal Feed has a number of monitoring programmes through which it keeps a finger on the pulse. By studying the results it is able to detect undesirable developments promptly and see how they are to be managed. The monitoring programme for chemical contaminants focuses on aflatoxin, cadmium, pesticides and Salmonella.

The government has tried in many ways, including regulations, to limit or even prevent the pollution of surface water. For example, environmental permits generally stipulate the volume of waste products that a company may release into the surface water in a given period.

A monitoring programme for Dutch recreational fishing has been in place for many years. This measures the pollution of eels with PCBs, organochlorine compounds and mercury.

Fruit and vegetables are healthy. Scientific research has shown that if people were to eat more fruit and vegetables there would be considerably fewer cases of cancer. However the most recent dietary survey conducted in the Netherlands (Voedselconsumptiepeiling, VCP-3) shows that the consumption of fruit and vegetables has declined considerably.

The registration of chemicals that are used has been the usual practice in the Environmental Conscious Cultivation (Milieubewuste voedingstuinbouw, MBT) for several years. The aim of the programme is to stimulate environmentally aware horticulture.

In the Netherlands the Dutch government and agribusiness have set up the Multi-year Plan Crop Protection. One important objective for the year 2000 is to halve the use of pesticides in comparison to 1984-1986. Other goals are to make the agricultural sector in the year 2000 less dependent on chemicals and to reduce the emission of pesticides into the environment.

The Dutch dairy industry continually monitors the purity and safety of milk and dairy products, taking account of a large number of risk factors. The Quality Programme for Agricultural Products (KAP) deals only with the residues and contaminants covered by the dairy industry’s monitoring programmes: organochlorine chemicals, PCBs and aflatoxin.