title: [Concordance in blood lead quantification between laboratories].
abstract: OBJECTIVE
  To establish a blood lead quantification correlation from two occupational health laboratories (OHL1V and OHL2DF), and the ABC Hospital (LABC) metals laboratory.
  
  
  METHODS
  A cross-sectional study was performed in 84 workers from a voltage regulators company, where lead is welded; in 54 % (46 of them) a blood sample was taken and analyzed by OHL1V, and in 28.6 % (24) by OHL2DF. All samples were analyzed by atomic absorption spectrophotometry. Pearson correlation (r), coefficient of determination (r2), Lin (rho) concordance test, and Bland-Altman plots were calculated.
  
  
  RESULTS
  The blood lead mean: LABC was 5.8 ± 2.4 μg/dL vs. OHL2DF of 4.4 ± 3.6 μg/dL (r = 0.25 [p = 0.24], r2 = 0.06 [p = 0.24], and rho = 0.21 [p = 0.21]). And with LABC, 6.75 ± 3.3 μg/dL vs. OHL1V 5.6 ± 2.9 μg/dL (r = 0.91 [p < 0.001], r2 = 0.83 [p < 0001], and rho = 0.85 [p< 0.001]).
  
  
  CONCLUSIONS
  Agreement between LABC and OHL1V was poor (< 0.90), and with OHL2DF was null. An occupational health laboratory certification is needed in order to have reliable biological exposure index measurements in lead occupational exposure.
authors.affiliation: Unidad de Investigación en Salud en el Trabajo, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Distrito Federal, México. gpeaguilarm@gmail.com.
authors.forename: Cuauhtémoc Arturo
authors.initials: CA
authors.lastname: Juárez-Pérez
authors.forename: Yuliana Fabiola
authors.initials: YF
authors.lastname: Zempoalteca-Angulo
authors.forename: Luis Cuauhtémoc
authors.initials: LC
authors.lastname: Haro-García
authors.forename: Adriana
authors.initials: A
authors.lastname: Mercado-García
authors.forename: Carmina
authors.initials: C
authors.lastname: Jiménez-Ramírez
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Aguilar-Madrid
mesh_terms: D064790:Clinical Laboratory Services / Q000592:standards* / Q000706:statistics & numerical data; D003430:Cross-Sectional Studies; D055615:Electrical Equipment and Supplies; D004785:Environmental Pollutants / Q000097:blood*; D006801:Humans; D007854:Lead / Q000097:blood*; D066192:Manufacturing Industry; D016273:Occupational Exposure / Q000032:analysis*; D016272:Occupational Health; D011786:Quality Control; D015203:Reproducibility of Results; D013054:Spectrophotometry, Atomic
chemical_list: D004785:Environmental Pollutants; D007854:Lead
keywords: Blood lead; Occupational health