title: Case report: human exposure to dioxins from clay.
abstract: BACKGROUND
  For the general population, the dominant source of exposure to dioxin-like compounds is food. As part of the University of Michigan Dioxin Exposure Study (UMDES), we measured selected polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) in serum of 946 subjects who were a representative sample of the general population in five Michigan counties.
  
  
  METHODS
  The total toxic equivalency (TEQ; based on 2005 World Health Organization toxic equivalency factors) of serum from the index case was 211 ppt on a lipid-adjusted basis, which was the highest value observed in the UMDES study population. This subject had no apparent opportunity for exposure to dioxins, except that she had lived on property with soil contaminated with dioxins for almost 30 years, and had been a ceramics hobbyist for > 30 years. Soil from her property and clay that she used for ceramics were both contaminated with dioxins, but the congener patterns differed.
  
  
  CONCLUSIONS
  The congener patterns in this subject's serum, soil, and ceramic clay suggest strongly that the dioxin contamination in clay and not soil was the dominant source of dioxin contamination in her serum. RELEVANCE TO PUBLIC HEALTH PRACTICE: It appears that ceramic clay, in particular the process of firing clay with unvented kilns, can be a significant nonfood and nonindustrial source of human exposure to dioxins among ceramics hobbyists. The extent of human exposure from ceramic clay is unclear, but it may be widespread. Further work is needed to more precisely characterize the routes of exposure.
authors.affiliation: Department of Environmental Health Sciences, University of Michigan School of Public Health, 109 South Observatory Street, Ann Arbor, MI 48109, USA. afranz@umich.edu
authors.forename: Alfred
authors.initials: A
authors.lastname: Franzblau
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Hedgeman
authors.forename: Qixuan
authors.initials: Q
authors.lastname: Chen
authors.forename: Shih-Yuan
authors.initials: SY
authors.lastname: Lee
authors.forename: Peter
authors.initials: P
authors.lastname: Adriaens
authors.forename: Avery
authors.initials: A
authors.lastname: Demond
authors.forename: David
authors.initials: D
authors.lastname: Garabrant
authors.forename: Brenda
authors.initials: B
authors.lastname: Gillespie
authors.forename: Biling
authors.initials: B
authors.lastname: Hong
authors.forename: Olivier
authors.initials: O
authors.lastname: Jolliet
authors.forename: James
authors.initials: J
authors.lastname: Lepkowski
authors.forename: William
authors.initials: W
authors.lastname: Luksemburg
authors.forename: Martha
authors.initials: M
authors.lastname: Maier
authors.forename: Yvan
authors.initials: Y
authors.lastname: Wenger
mesh_terms: D000368:Aged; D000538:Aluminum Silicates; D000077215:Clay; D004147:Dioxins / Q000097:blood / Q000633:toxicity*; D004781:Environmental Exposure; D005260:Female; D006801:Humans
chemical_list: D000538:Aluminum Silicates; D004147:Dioxins; D000077215:Clay