People who smoke are more likely to use other substances as well.
"I did begin by using substances to get there, and started drinking very early."
Most use other substances as well, so it is important to be able to intervene for a variety of problems.
These children or teens are also at a higher risk of using illegal substances.
There have been a number of other substances used for ammonia control.
At the moment our primary concern should be to reduce the range of substances used by the chemical industry.
You can also pay attention to your teen's activities and peers who might be using substances.
Farmers in Europe will be banned from using particular substances.
Instead, some could have come from the special substances used in the laboratory to study brain tissue.
The sound inside the city died quickly, muffled by the strange substance used in the walls.