Did you know nearly one in ten American adults and teenagers have a drug and/or alcohol dependence problem? That one person could be your neighbor, cousin, teenager's best friend or even your co-worker. Odds are, you know someone who is currently struggling with alcoholism or drug abuse.

The workplace is not immune to drug abuse. In fact, most substance abusers are employed. In a survey of callers to the national cocaine hotline, 18 percent of callers confessed to stealing from coworkers to support their addiction, and 64 percent admitted that their drug use negatively affected their performance.

And it’s not just illicit drugs that contribute to workplace hazards. Prescription drugs like sleeping pills, sedatives and pain killers are hazardous too.

Working under the influence affects reflexes and reaction time, concentration, perceptions and judgment. People who work under the influence and cause accidents are often the ones who are injured, and the accidents they cause can also injure other people.

Here are some important facts to know about drugs:

• Marijuana is the most common illegal drug used on the job.
• Experts warn that addiction can happen very quickly. In the case of heroin, a person could become addicted after just one use.
• Although alcohol is a legal substance, it is still a drug, and it can be highly addictive.
• Inhalants such as airplane glue, paint thinner, aerosols, nitrous oxide, amyl nitrate and butyl nitrate contain very hazardous chemicals that can be deadly.

To prevent situations that jeopardize safety in your workplace, learn to recognize these 10 signs of possible substance abuse:

1. Frequent work absences and late arrivals
2. Poor concentration and coordination; slow mental and physical reflexes
3. Restlessness, nervousness, paranoia
4. Argumentative, defensive behavior, and/or blaming others for problems
5. Letting responsibilities slide; loss of interest in work
6. Impaired judgment and decision making
7. Mood swings; bizarre or violent behavior
8. “Revved-up” movements and speech
9. Forgetfulness and carelessness
10. Pushing beyond physical capacity