Table 3

 Adjusted* prevalence OR and 95% CI of attention deficit disorder by category of seven persistent organic pollutants

POPsDetection rate (%)Non-detectable POPsDetectable POPsp Value
POP, persistent organic pollutant.
*Adjustment for age, race/ethnicity, sex, poverty index ratio, mother’s age at pregnancy, birth weight, cigarette smoking during pregnancy, body mass index and saturated fat intake.
†Median (interquartile range).
3,3′,4,4′,5-penta chlorobiphenyl22.4Concentration (ng/g of lipid)†9.1 (6.7–20.6)
Cases/n20/2086/69
Prevalence (%)9.68.7
Adjusted* OR (95% CI)Referent1.03 (0.37 to 2.88)0.96
1,2,3,4,6,7,8-hepta chlorodibenzo-p-dioxin30.5Concentration (pg/g of lipid)†38.9 (30.2–50.9)
Cases/n12/19114/86
Prevalence (%)6.316.3
Adjusted* OR (95% CI)Referent3.41 (1.08 to 10.8)0.04
1,2,3,4,6,7,8,9-octachlorodibenzo-p-dioxin26.8Concentration (pg/g of lipid)†23.0 (18.5–30.2)
Cases/n12/19914/78
Prevalence (%)6.018.0
Adjusted* OR (95% CI)Referent3.33 (0.94 to 11.8)0.06
1,2,3,4,6,7,8-hepta chlorodibenzofuran31.9Concentration (pg/g of lipid)†10.0 (7.8–14.8)
Cases/n13/18913/88
Prevalence (%)6.914.8
Adjusted* OR (95% CI)Referent2.31 (0.62 to 8.63)0.20
β-hexachlorocyclo hexane22.4Concentration (ng/g of lipid)†17.9 (14.6–26.4)
Cases/n23/2013/76
Prevalence (%)11.44.0
Adjusted* OR (95% CI)Referent0.44 (0.08 to 2.62)0.34
Trans-nonachlor25.4Concentration (ng/g of lipid)†10.9 (8.4–16.0)
Cases/n17/2079/70
Prevalence (%)8.212.9
Adjusted* OR (95% CI)Referent1.58 (0.57 to 4.42)0.35
Detectable<50thDetectable⩾50th
p,p′-dichlorodiphenyl trichloroethane100Concentration (ng/g of lipid)†75.3 (49.0–98.4)278 (186–528)
Cases/n17/1389/139
Prevalence (%)12.36.5
Adjusted* OR (95% CI)Referent1.25 (0.30 to 5.26)0.74