There are different strategies that can be used to reduce hazardous waste. The amount of waste is highly dependent on the reaction and the strategy to reduce waste will depend greatly on the purpose of the reaction in the first place (i.e. when producing a product, scaling down is generally not an option).
1. Rethink the method used to produce a product and see if there is an alternate method that will produce less waste.
2. Work to use catalysts and reaction conditions so that production of a product is more efficient.
3. In research, consider if smaller quantities of the product will be sufficient and scale down the amounts of reactants.
4. Find ways to recover and use the waste products in other reactions.
5. Find ways to react the waste in a secondary reaction to produce products that are not hazardous or are at least less hazardous.