September 11, 2005

Fred Middleton

(662) 449-0000

Tests Show Exposure to Boric Acid as Fire Retardant Well Below EPA Threshold Level 

SOUTHAVEN, MS - In independent testing to measure emissions from mattresses using boric acid-treated cotton batting as a flame retardant, toxicologists determined that boric acid exposure is not expected to present any significant health risks to consumers, according to a report released by the National Cotton Batting Institute.

“Based on normal consumer use patterns, the dermal and oral exposure to boric acid through contact with mattresses is more than 1400-fold less than the Environmental Protection Agency’s threshold level,” said NCBI President Alan Posner in reviewing the findings with staff of the Consumer Product Safety Commission. “The anticipated boric acid exposure is also well below human health criteria established by the Agency for Toxic Substances and Disease Registry (ATSDR) and the National Academy of Sciences (NAS).”

The testing was commissioned by the NCBI, which represents U.S. companies that manufacture flame-resistant cotton batting used in mattresses, futons and upholstered furniture as well as fiber suppliers and suppliers of boron-based boric acid that is used to make the cotton flame resistant. It followed NCBI’s comments at a CPSC hearing last March on the proposed national mattress flammability standard at which it was noted that gaps existed in studies exploring the safe use of boric acid in consumer bedding.

“Cotton batting produced by NCBI members already is submitted to mandatory testing by Underwriters Laboratories for smolder and flame resistance as the product is produced,” Posner said. “This product certification is required for NCBI membership.

“The recent testing was in response to questions posed about ingestion, air quality and dermal absorption as the result of sleeping on mattresses constructed with cotton batting that has been treated with boric acid.

“At that time, there were no quantifiable answers to those questions. We believe the result of these extensive tests puts to rest any concerns about the safety of a product which has been used in mattresses for more than 30 years without the occurrence of a single known health issue.”

Nine mattress styles were tested utilizing the Cornell Impact Machine that put each mattress under duress for 15 minutes to determine the measurable release of boric acid onto the surface of the mattress and into the air. Wipe sampling was conducted on the mattress surface for boric acid immediately before and after the impact testing; duplicate air samples for boric acid determination were collected above the mattress being tested and in the room away from the test machine to measure background levels of boric acid during and immediately following the impact testing; and respirable dust emissions were measured in the air above the mattress and in the background.

“The evaluation of dermal exposure assumed direct contact between a mattress surface and unclothed skin,” Posner said. “That is unlikely to occur in most situations given the typical use of sheets and mattress pads. The model of exposure in these tests represents the high end of consumer exposure, which is far below EPA allowable thresholds (the allowable daily dose of boron was raised from 6.3 milligrams per day to 14 milligrams per day in August 2004).”

Among the findings were:

Air sampling tests found no detectable airborne boric acid, indicating inhalation is not considered as a pathway of exposure to boric acid.

There was no significant variance above the mattress and away from the mattress in the measurement of respirable particles, nor was there any observed increase in respirable particles over the course of the impact testing.

Although surface wipe tests contained measurable amounts of boric acid, there was not a consistent increase in surface concentrations following testing. Toxicologists determined that boric acid on the surface of the mattress does not contribute to human intake that would be considered significant from a health standpoint.

Protocol for the testing was developed by Legend Technical Services, Inc.; the testing was carried out by Stork Laboratories, Inc.; and the test results were analyzed by toxicologists at Geomatrix, Inc.