title: Can living in the surroundings of a petrochemical complex be a risk factor for autoimmune thyroid disease?
abstract: BACKGROUND
  Based on a suspicion raised by a health professional and due to a subsequent legal request, a cross-sectional study was made with a comparison group to investigate a possible excess of Hashimoto's thyroiditis-HT and antibodies-ATA in the surroundings of a Petrochemical Complex.
  
  
  METHODS
  People of both sexes aged over 20 years were investigated in a random sample of residents in the area surrounding the Petrochemical Complex. Controls were investigated in an area with steel industries. In the areas searched, participants were chosen randomly and stratified a priori by sex and age group. As a result, 90.5% of the expected sample was obtained, totaling 1533 individuals. HT and ATA prevalences were compared by the chi-square test. Logistic regression was used to control the possible confounding factors for HT and ATA.
  
  
  RESULTS
  Both TH (9.3%) and ATA (17.6%) prevalences were higher in the Petrochemical Complex area than in the control area (3.9% and 10.3%, respectively). After controlling the possible confounding factors, the POR for living in the surroundings of the Complex and presenting HT was 2.39 (CI95%: 1.42-4.03). According to the ATA criterion, the POR for living in the surroundings of the Complex was 1.78 (CI95%: 1.23-2.60).
  
  
  CONCLUSIONS
  The authors have found higher prevalence and risk of developing thyroiditis and anti-thyroid antibodies among residents of areas surrounding the Petrochemical Complex and think these findings need to be further studied in similar areas.
authors.affiliation: Epidemiological Surveillance Center-CVE/SES/SP, Arnaldo, 351, 6(o) Andar, São Paulo/SP-CEP:01246-000, Brasil. umbelino.freitas@gmail.com
authors.forename: Clarice Umbelino
authors.initials: CU
authors.lastname: de Freitas
authors.forename: Rosária A
authors.initials: RA
authors.lastname: Grimaldi Campos
authors.forename: Mirta Alcira F
authors.initials: MA
authors.lastname: Rodrigues Silva
authors.forename: Maria Rosana I
authors.initials: MR
authors.lastname: Panachão
authors.forename: Jose Cássio
authors.initials: JC
authors.lastname: de Moraes
authors.forename: William
authors.initials: W
authors.lastname: Waissmann
authors.forename: Antônio
authors.initials: A
authors.lastname: Roberto Chacra
authors.forename: Marina Y S
authors.initials: MY
authors.lastname: Maeda
authors.forename: Regina S
authors.initials: RS
authors.lastname: Minazzi Rodrigues
authors.forename: James
authors.initials: J
authors.lastname: Gonçalves Belchor
authors.forename: Sonia
authors.initials: S
authors.lastname: Oliveira Barbosa
authors.forename: Raimunda Telma M
authors.initials: RT
authors.lastname: Santos
mesh_terms: D000328:Adult; D000393:Air Pollutants / Q000633:toxicity*; D001323:Autoantibodies / Q000097:blood / Q000276:immunology; D001938:Brazil / Q000453:epidemiology; D002617:Chemical Industry; D003430:Cross-Sectional Studies; D019652:Extraction and Processing Industry; D005260:Female; D050031:Hashimoto Disease / Q000139:chemically induced* / Q000453:epidemiology / Q000276:immunology; D006801:Humans; D007455:Iodine / Q000652:urine; D008297:Male; D008875:Middle Aged; D010126:Ozone / Q000633:toxicity; D052638:Particulate Matter / Q000633:toxicity; D010578:Petroleum; D015995:Prevalence; D012111:Residence Characteristics; D012307:Risk Factors; D011795:Surveys and Questionnaires; D013960:Thyroid Function Tests; D055815:Young Adult
chemical_list: D000393:Air Pollutants; D001323:Autoantibodies; D052638:Particulate Matter; D010578:Petroleum; D010126:Ozone; D007455:Iodine