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As sediments are an integral part of the aquatic environment, several studies have focused on the fate and effects of silicones in sediments. During wastewater treatment, in particular non-volatile silicones bind tightly to particulates. They are thus removed from wastewater during treatment and are processed as part of the sludge.

The sludge is normally either sent to landfill, incinerated or used to improve the quality of soils used for agriculture or other purposes (e.g. for golf courses, landscaping, etc.).

A minor percentage (less than 5%) of silicones adheres to suspended solids in the water outlet of treatment plants and may become part of river sediments. In laboratory experiments with PDMS on a number of sediment-living organisms, such as worms and insect larvae, no adverse effects were seen even at high concentrations.