DETROIT (Reuters) - Toyota Motor Corp recalled 247,000 cars, SUVs and pickup trucks in the United States on Monday because of potentially defective front passenger air bag inflators from Japan's Takata Corp that can rupture and spray metal shrapnel, according to U.S. safety regulators.
That raised the number of vehicles affected by regional recalls launched in June by several automakers due to the Takata air bags to more than 4.5 million.
The regional recalls by Toyota and other automakers including Honda Motor and Fiat Chrysler Automobiles' Chrysler Group began in high-humidity areas of the United States after the National Highway Traffic Safety Administration (NHTSA) started investigating reports of air bag explosions in Florida and Puerto Rico.
Prompted by NHTSA, Takata and automakers have been trying to determine whether exposure to high humidity caused any defect in the inflators collected though the regional recalls.
"At this point, the issue appears to be a problem related to extended exposure to consistently high humidity," NHTSA said in a statement on Monday. "However, we are leaving no stone unturned in our aggressive pursuit to track down the full geographic scope of this issue."
Toyota recovered replaced air bag inflators from south Florida and Takata evaluated them starting in August, according to the NHTSA documents. On Oct. 10, Takata informed Toyota that a number of the inflators performed "improperly" during testing. Five days later, after reviewing the data with NHTSA, Toyota decided on the recall.
Over the last six years, Takata has recalled about 16 million vehicles globally for defective air bags, including the regional recalls. At least four deaths, all in Honda cars, have been linked to the defective air bags.
The Toyota vehicles affected by Monday's recall are from model years 2002 through 2005, according to the NHTSA documents. They include the Lexus SC and Toyota Corolla, Matrix, Sequoia and Tundra. Also part of the recall is General Motors' Pontiac Vibe, which was built by Toyota.
A Toyota spokeswoman said the automaker was not aware of any crashes, injuries or deaths related to the recall.
Takata spokesman Alby Berman said the supplier supported Toyota's latest recall and said, "We will continue to fully support the NHTSA investigation and our customers’ recalls in every way possible moving through this processes, including ongoing detailed technical analysis and replacement parts."
Dealers will replace the front passenger airbag inflator with a newly made replacement. If a replacement is not available as a temporary measure the dealer will disable the air bag and advise the customer not to use the front passenger seat, according to the NHTSA documents.
Other automakers affected by the regional recalls include BMW, Ford Motor, Mazda Motor, Mitsubishi Motors, Nissan Motor and Fuji Heavy Industries' Subaru.
Reporting by Ben Klayman in Detroit; Editing by Tom Brown and Lisa Shumaker