Thomas Webster

Dr. Thomas Webster

orcid

Research Focus & Metrics

Academic Career Length

30Years (1997-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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13 August 2009 in Environmental Science & Technology
Verified
Journal Article
Closed access
HSHeather M. Stapleton
Heather M. Stapleton
SKSusan Klosterhaus
Susan Klosterhaus
SESarah Eagle
Sarah Eagle
JFJennifer Fuh
Jennifer Fuh
JMJohn Meeker
John Meeker
TWThomas Webster
Thomas Webster

1 February 2010 in Environmental Health Perspectives
Verified
Journal Article
Open access
JNJessica W. Nelson
Jessica W. Nelson
EHElizabeth E. Hatch
Elizabeth E. Hatch
TWThomas Webster
Thomas Webster
A peer-reviewed open access journal published by the National Institute of Environmental Health Sciences

23 July 2008 in Environmental Science & Technology
Verified
Journal Article
Closed access
HSHeather M. Stapleton
Heather M. Stapleton
JAJoseph G. Allen
Joseph G. Allen
SKShannon M. Kelly
Shannon M. Kelly
AKAlex Konstantinov
Alex Konstantinov
SKSusan Klosterhaus
Susan Klosterhaus
TWThomas Webster
Thomas Webster

18 May 2011 in Environmental Science & Technology
Verified
Journal Article
Open access
HSHeather M. Stapleton
Heather M. Stapleton
SKSusan Klosterhaus
Susan Klosterhaus
AKAlex Keller
Alex Keller
PFP. Lee Ferguson
P. Lee Ferguson
SBSaskia van Bergen
Saskia van Bergen
ABArlene Blum
Arlene Blum
With the phase-out of PentaBDE in 2004, alternative flame retardants are being used in polyurethane foam to meet flammability standards. However, insufficient information is available on the identity of the flame retardants currently in use. Baby products containing polyurethane foam must meet California state furniture flammability standards, which likely affects the use of flame retardants in baby products throughout the U.S. However, it is unclear which products contain flame retardants and at what concentrations. In this study we surveyed baby products containing polyurethane foam to investigate how often flame retardants were used in these products. Information on when the products were purchased and whether they contained a label indicating that the product meets requirements for a California flammability standard were recorded. When possible, we identified the flame retardants being used and their concentrations in the foam. Foam samples collected from 101 commonly used baby products were analyzed. Eighty samples contained an identifiable flame retardant additive, and all but one of these was either chlorinated or brominated. The most common flame retardant detected was tris(1,3-dichloroisopropyl) phosphate (TDCPP; detection frequency 36%), followed by components typically found in the Firemaster550 commercial mixture (detection frequency 17%). Five samples contained PBDE congeners commonly associated with PentaBDE, suggesting products with PentaBDE are still in-use. Two chlorinated organophosphate flame retardants (OPFRs) not previously documented in the environment were also identified, one of which is commercially sold as V6 (detection frequency 15%) and contains tris(2-chloroethyl) phosphate (TCEP) as an impurity. As an addition to this study, we used a portable X-ray fluorescence (XRF) analyzer to estimate the bromine and chlorine content of the foam and investigate whether XRF is a useful method for predicting the presence of halogenated flame retardant additives in these products. A significant correlation was observed for bromine; however, there was no significant relationship observed for chlorine. To the authors knowledge, this is the first study to report on flame retardants in baby products. In addition, we have identified two chlorinated OPFRs not previously documented in the environment or in consumer products. Based on exposure estimates conducted by the Consumer Product Safety Commission (CPSC), we predict that infants may receive greater exposure to TDCPP from these products compared to the average child or adult from upholstered furniture, all of which are higher than acceptable daily intake levels of TDCPP set by the CPSC. Future studies are therefore warranted to specifically measure infants exposure to these flame retardants from intimate contact with these products and to determine if there are any associated health concerns.

28 November 2012 in Environmental Science & Technology
Verified
Journal Article
Open access
HSHeather M. Stapleton
Heather M. Stapleton
SSSmriti Sharma
Smriti Sharma
GGGordon Getzinger
Gordon Getzinger
PFP. Lee Ferguson
P. Lee Ferguson
MGMichelle Gabriel
Michelle Gabriel
ABArlene Blum
Arlene Blum
California’s furniture flammability standard Technical Bulletin 117 (TB 117) is believed to be a major driver of chemical flame retardant (FR) use in residential furniture in the United States. With the phase-out of the polybrominated diphenyl ether (PBDE) FR mixture PentaBDE in 2005, alternative FRs are increasingly being used to meet TB 117; however, it was unclear which chemicals were being used and how frequently. To address this data gap, we collected and analyzed 102 samples of polyurethane foam from residential couches purchased in the United States from 1985 to 2010. Overall, we detected chemical flame retardants in 85% of the couches. In samples purchased prior to 2005 (n = 41) PBDEs associated with the PentaBDE mixture including BDEs 47, 99, and 100 (PentaBDE) were the most common FR detected (39%), followed by tris(1,3-dichloroisopropyl) phosphate (TDCPP; 24%), which is a suspected human carcinogen. In samples purchased in 2005 or later (n = 61) the most common FRs detected were TDCPP (52%) and components associated with the Firemaster550 (FM 550) mixture (18%). Since the 2005 phase-out of PentaBDE, the use of TDCPP increased significantly. In addition, a mixture of nonhalogenated organophosphate FRs that included triphenyl phosphate (TPP), tris(4-butylphenyl) phosphate (TBPP), and a mix of butylphenyl phosphate isomers were observed in 13% of the couch samples purchased in 2005 or later. Overall the prevalence of flame retardants (and PentaBDE) was higher in couches bought in California compared to elsewhere, although the difference was not quite significant (p = 0.054 for PentaBDE). The difference was greater before 2005 than after, suggesting that TB 117 is becoming a de facto standard across the U.S. We determined that the presence of a TB 117 label did predict the presence of a FR; however, lack of a label did not predict the absence of a flame retardant. Following the PentaBDE phase out, we also found an increased number of flame retardants on the market. Given these results, and the potential for human exposure to FRs, health studies should be conducted on the types of FRs identified here.

17 January 2007 in Environmental Science & Technology
Verified
Journal Article
Closed access
NWNerissa Wu
Nerissa Wu
THThomas Herrmann
Thomas Herrmann
OPOlaf Paepke
Olaf Paepke
JTJoel Tickner
Joel Tickner
RHRobert Hale
Robert Hale
TWThomas Webster
Thomas Webster