As this is such a controversial and large subject, many experiments could be branched off of my original experiment. More variables could be included such as experimenting the amount of detergent left when you use warm water instead of cold water. This would show the amount of detergent left over on our towels and undergarments, as well as how temperature affects the rate at which the detergent dissolves. Another experiment could include the measuring of the exact amount of the "filler" material in the different types of detergent brands. It would be interesting to discover the price : detergent (actual, not filler) ratio. Finally, the most practical but advanced research would be to experiment on actual humans the effect of detergents. A reasonable amount of detergent could be placed on the subject's skin and one would observe the affects of the detergents on the person's skin.