NEW YORK -- Hybrid trucks and cars reduce emissions pollution coming out of exhaust pipes, but it's the low levels of noise pollution that has at least one New York lawyer sending warning shots across the industry's bow. 

"Hybrid cars may be good for the environment but a new study shows these quiet vehicles are more dangerous than other cars for pedestrians and bicycle riders," Steven J. Schwartzapfel, a partner in the New York personal injury firm of Schwartzapfel Truhowsky Marcus P.C., says in a press release.

Schwartzapfel cites a recent report by the National Highway Traffic Safety Administration that found that some hybrid vehicles that are typically quieter than internal combustion cars and trucks, can pose a greater risk to unsuspecting pedestrians and bicyclists. 

The study was conducted on a total of 8,387 hybrid electric vehicles (HEVs) and 559,703 internal combustion (ICE) vehicles. A total of 77 and 3,578 pedestrians were involved in crashes with HEVs and ICE vehicles, respectively; and 48 and 1,862 bicyclists,.

Pedestrian and bicyclist crashes involving both types of vehicles commonly occurred on roadways, in zones with low speed limits, during daytime and in clear weather, but with higher incidence rates for HEVs. In some maneuvers, such as stopping, backing up, or entering or leaving a parking space, hybrids were twice as likely to be involved.

Schwartzapfel says the results should serve as a guide when designing future HEVs pedestrian and bicyclist crash prevention programs, such as requiring a minimum noise level for vehicles.

Hidden speakers that play emulated or recorded engine sounds may do the trick.

"Hybrid manufacturers and drivers are now on notice that they need to take steps to make sure their (vehicles) are seen and heard by cyclists and pedestrians," he says.

And, of course, the clincher: "They may be held accountable for injuries when they fail to take those steps."