These species are important to ecosystems as they remove substances that would otherwise take a long time to decompose.

This process removes unwanted substances from the oil, prior to refining.

The treatment plants are not equipped to remove toxic substances.

A type of treatment to remove unhealthy substances, such as metals and plaque, from the system.

Wastes also are usually treated to remove poisonous substances.

Both methods can also remove other substances from the sample.

Removing drugs, metals, toxins, and cancer-causing substances from the body.

The crude oil will generally need to be purified to remove residual water, solid materials, other substances and so on.

That could well mean offering help to companies to remove carcinogenic substances from the workplace.

Brain function can be affected when the liver stops working and cannot remove toxic substances from the body.