title: Strategies to Reduce Tin and Other Metals in Electronic Cigarette Aerosol.
abstract: BACKGROUND
  Metals are present in electronic cigarette (EC) fluid and aerosol and may present health risks to users.
  
  
  OBJECTIVE
  The objective of this study was to measure the amounts of tin, copper, zinc, silver, nickel and chromium in the aerosol from four brands of EC and to identify the sources of these metals by examining the elemental composition of the atomizer components.
  
  
  METHODS
  Four brands of popular EC were dissected and the cartomizers were examined microscopically. Elemental composition of cartomizer components was determined using integrated energy dispersive X-ray microanalysis, and the concentrations of the tin, copper, zinc silver, nickel, and chromium in the aerosol were determined for each brand using inductively coupled plasma optical emission spectroscopy.
  
  
  RESULTS
  All filaments were made of nickel and chromium. Thick wires were copper coated with either tin or silver. Wires were joined to each other by tin solder, brazing, or by brass clamps. High concentrations of tin were detected in the aerosol when tin solder joints were friable. Tin coating on copper wires also contributed to tin in the aerosol.
  
  
  CONCLUSIONS
  Tin concentrations in EC aerosols varied both within and between brands. Tin in aerosol was reduced by coating the thick wire with silver rather than tin, placing stable tin solder joints outside the atomizing chamber, joining wires with brass clamps or by brazing rather than soldering wires. These data demonstrate the feasibility of removing tin and other unwanted metals from EC aerosol by altering designs and using materials of suitable quality.
authors.affiliation: Department of Cell Biology and Neuroscience, University of California Riverside, Riverside, California, United States of America.
authors.forename: Monique
authors.initials: M
authors.lastname: Williams
authors.affiliation: Department of Cell Biology and Neuroscience, University of California Riverside, Riverside, California, United States of America.
authors.forename: An
authors.initials: A
authors.lastname: To
authors.affiliation: Central Facility for Advanced Microscopy and Microanalysis, University of California Riverside, Riverside, California, United States of America.
authors.forename: Krassimir
authors.initials: K
authors.lastname: Bozhilov
authors.affiliation: Department of Cell Biology and Neuroscience, University of California Riverside, Riverside, California, United States of America.
authors.forename: Prue
authors.initials: P
authors.lastname: Talbot
mesh_terms: D000280:Administration, Inhalation; D000336:Aerosols / Q000737:chemistry*; D002857:Chromium / Q000032:analysis; D066300:Electronic Nicotine Delivery Systems / Q000295:instrumentation*; D008670:Metals / Q000032:analysis*; D008855:Microscopy, Electron, Scanning; D009532:Nickel / Q000032:analysis; D012834:Silver / Q000032:analysis; D014001:Tin / Q000032:analysis; D015032:Zinc / Q000032:analysis
chemical_list: D000336:Aerosols; D008670:Metals; D002857:Chromium; D012834:Silver; D014001:Tin; D009532:Nickel; D015032:Zinc