Janairo said overexposure to ALPG could lead to "unconsciousness and even death.
It is important that installations should be done only by an ALPG installer approved by the Department of Trade and Industry to ensure that the setup is correctly done," Janairo said in a statement.
Only by introducing regulations and standards to ensure the safe use of ALPG can we ensure the health and safety not only of drivers but also passengers," he added.
Janairo said the study covered 26 ALPG and 13 conventional-vehicle male drivers who were randomly selected from a list of users of auto LPG-powered vehicles and users of conventional vehicles (diesel and gasoline).
The study covered 53 taxis: 28 ALPG taxis, and 25 gasoline or diesel taxis, he added.
ALPG is cleaner than conventional automotive fuels.
Janairo said countries with large numbers of LPG vehicles and high consumption of ALPG include the United States, Japan, Australia and Canada.