AUSTIN, Texas – Nighttime driving is becoming more hazardous for American teenagers and the likely cause is talking and texting on cell phones while operating a vehicle, according to a study released Thursday.

The report by the Texas Transportation Institute said the proportion of fatal crashes at night involving drivers 16 to 19 years old nationwide increased 10 percent from 1999 to 2008. The percentage of nighttime fatal crashes involving drivers 20 years and older rose nearly 8 percent from 1999 to 2008.

While the increase in nighttime crashes in the older age group can be attributed primarily to alcohol use, the study authors pointed to driver distraction caused by talking and texting on cell phones as a likely cause of the increase in fatalities among younger drivers.

“We know driving at night is dangerous. We know using a cell phone behind the wheel compromises your ability to drive,” said Bernie Fette, senior research specialist for the Texas Transportation Institute. “Put those together and you’ve created a perfect storm.”

Nighttime driving carries inherent risks of decreased visibility and slower response due to driver fatigue. Those risks are even greater for teenagers who are inexperienced night drivers, Fette said.

The number of fatal crashes, including those at night, actually dropped between 1999 and 2008, but the percentage that occurred at night increased.