Diatomaceous earth is generally regarded as safe . It is used as a pest control as its course can destroy exoskeletons of many bugs and insects. While no link has been found between human exposure and cancer, it is generally advised to limit your exposure. At the pool, this can happen by creating a slurry instead of dumping the powder directly into the skimmer.
Because many municipalities have banned backwashing D.E. into city streets, alternative options have become available. Cellulose fiber (wood pulp) is become more popular as a filtration media. It can be used to replace D.E. or as a temporary additive to your sand or cartridge filter. Unlike D.E., cellulose is biodegradable and is environmentally friendly. When used as a replacement for D.E. you use ¼ the amount. Similar ot concentrated laundry detergent, using too much will impair performance.
When using cellulose, your first filter run will be shorter because of its improved ability to remove smaller particulates from your pool. An advantage of using cellulose as a replacement over D.E. is that it filters throughout the entire filter cake, not just on the surface.
As an additive, cellulose can be mixed with water and applied through the skimmer. After running your filter for 24 hours, a backwash needs to be performed to prevent the cellulose from sinking and mixing into the sand bed.
Adding cellulose to a new cartridge filter can speed up the removal of particulates, and protect the new cartridges against early aging. Once the water is clear, the cartridge should be cleaned off, and then run as normal.