Although widely accepted all over the world as a concept, the goal of sustainable development has a noteworthy weakness - the difficulty of measuring sustainability. A sustainability indicator should tell us if, and to what degree, we are making progress toward the goal of sustainability. In the Netherlands, it has been a policy goal to reduce the physical amount of pesticides used in agriculture. Such a reduction, however, does not necessarily imply fewer environmental impacts. In fact, Reus shows that dosages of pesticides and impacts on the environment are not significantly correlated.
Farmers lack information about the environmental impacts of pesticides and fertilizers they use.
If considered important for a particular crop or pesticide, the yardstick can include additional effects such as measures of food safety. They are calculated by computer models that predict the leaching of pesticides into ground water, soil and surface water and their biodegradation. To measure the environmental impacts of pesticides, methods derived from the pesticide registration procedure of the Dutch government are used. Reference points of the yardstick according to proposed Dutch environmental standards are set at 100. Actual scores below 100 are considered to be acceptable.