Teens who have easy access to drugs or alcohol may be at increased risk of substance use in adulthood, a new study suggests. The effects are stronger for white people and males, UPI reports.

Researchers from Michigan State University analyzed data from 15,000 teens and young adults. The study found teens with easy access began using drugs and alcohol at a younger age, and were more likely to be using one or both substances later in life. The findings appear in the Journal of Child and Adolescent Substance Abuse.

“These findings provide evidence that the availability of illegal drugs and alcohol in the home while growing up is a critical factor in the later use of substances,” lead researcher Cliff Broman said in a news release.