Record Display for the EPA National Library Catalog

RECORD NUMBER: 237 OF 5073

OLS Field Name OLS Field Data
Main Title Antimony in brake pads - a carcinogenic component? /
Author Uexkèull, Ole von,
Publisher [Publisher not identified],
Year Published 2002
OCLC Number 898352768
Subjects Automobiles--Brakes--Environmental aspects. ; Metals--Environmental aspects.
Local Library Info
Library Local Subject Local Note
ERA copper-brake; wear debris; aerodynamic diameter; particle size distribution; characterization Brake Pad Partnership Technical Reference Library no.19.
Holdings
Library Call Number Additional Info Location Last
Modified
Checkout
Status
ERAM  TL269.B73 no.19 Brake Pad Partnership Region 9 Library/San Francisco,CA 12/22/2014
Collation 12 unnumbered pages : illustrations, tables ; 28 cm
Notes
Caption title. "For submission to the Journal of Cleaner Production." Includes bibliographical references.
Contents Notes
Describes concentrations of various metals, including copper, in pad material and wear debris generated from commercially available disc and drum vehicle brake pads obtained in Europe. Aerodynamic diameter wear debris particle size distributions were measured with an optical particle counter. Report includes scanning electron microscope photos of wear debris and comparisons of metal concentrations (including copper) with other brake pad studies conducted since 1996. Antimony trisulfide (Sb2S3) is used as a lubricant in friction material. X-ray diffraction analysis revealed Sb in 3/3 disc brake pads (range 41,000-46,000 mg/kg) and in 2/2 disc brake dust samples (21,000 and 17,000 mg/kg) from trucks. Considerably lower concentrations were found in drum brake pads (3/5, 59-6400 mg/kg) and in drum brake dust (4/18, 78-2800 mg/kg). Other toxic metals were also detected in pads and dust. The health risk of Sb in particulate brake emissions should be dependent on particle size and chemical entity, in particular solubility. A significant amount of the emitted dust was shown by size-fractionated optical particle counting to be inhalable in environmental ( > 90% mass) and occupational ( > 50% mass) exposure situations. Differentiation via selective solubility showed a considerable amount of Sb2S3 to oxidize during the braking process, likely leading to the formation of Sb2O3, a suspected human carcinogen. Sb in brake dust was soluble in calf serum (8.5 +/- 1.2%, 8.9 +/- 1.7 mg/l at 37degreesC for 3 d). Hence, the use of Sb in friction material should be suspected to pose a human cancer risk and be deterred. To design healthy and environmentally sound alternatives, we propose to apply the Intelligent Product System that distinguishes products of consumption and products of service. Brake pads are true products of consumption, because they are released to biological cycles, and should thus consist of materials with positively defined health and environmental properties.