Replacing a hazardous substance may be costly or seem unnecessary to the people producing or using it. Also, developing new – less hazardous substance – is resource demanding, and most companies hesitate to take the risk if they aren’t sure that the market will buy the new product. To encourage this, there needs to be an incentive for change. Substitution policies have been effective when used. There are many examples where the use of hazardous substances has been reduced or eliminated by replacing them with easily available substitutes.
Some countries apply this principle in their pesticides policies, prescribing that farmers use the least hazardous substance to achieve their goal. In this way many hazardous pesticides have been phased out and replaced by less hazardous. A chemicals policy aimed at eliminating hazardous substances needs a mechanism to ensure that the hazardous substances deemed necessary by society are substituted as soon as possible.