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1	Associations of lead biomarkers and delta-aminolevulinic acid dehydratase and vitamin D receptor genotypes with hematopoietic outcomes in Korean lead workers Lee S-S, Lee B-K, Lee G-S, Stewart WF, Simon D, Kelsey K, Todd AC, Schwartz BS. Scand J Work Environ Health 2001;27(6):402-412 Aims to compare and contrast associations of dimercaptosuccinic acid (DMSA)-chelatable lead, tibia lead, and blood lead with five hematopoietic outcomes to determine whether polymorphisms in the genes for δ-aminolevulinic acid dehydratase (ALAD) and the vitamin D receptor (VDR) modified relations among the lead biomarkers and the hematopoietic outcomes
2	Associations of Pb biomarkers and δ-ALAD & VDR with hematopoietic outcomes in Korean lead workers Lee et al. 2001 Methods cross-sectional study of 798 lead workers and 135 non-exposed controls in Korea DMSA-chelatable lead was measured as four-hour urinary lead excretion after oral administration of 10 mg/kg DMSA tibia lead was measured via ¹⁰⁹Cd-induced K-shell X-ray fluorescence (XRF).
3	Associations of Pb biomarkers and δ-ALAD & VDR with hematopoietic outcomes in Korean lead workers Lee et al. 2001 Results Lead-exposed subjects were 79.6% male, had a mean (SD) age of 40.4 (10.1) years, and a mean (SD) work duration of 8.1 (6.7) years. DMSA-chelatable lead levels ranged from 4.8 to 2,103 μg. Tibia lead ranged from -7 to 338 μg Pb/g bone mineral Blood lead ranged from 4 to 86 μg/dl
4	Associations of Pb biomarkers and δ-ALAD & VDR with hematopoietic outcomes in Korean lead workers Lee et al. 2001 Results
5	Associations of Pb biomarkers and δ-ALAD & VDR with hematopoietic outcomes in Korean lead workers Lee et al. 2001 Results After adjustment for covariates tibia lead was associated with all five hematopoietic outcomes blood lead and DMSA-chelatable lead were associated only with ZPP, ALAP, and ALAU Comparison of regression coefficients, total model adjusted R² values, and ΔR² values revealed that: blood lead was the best predictor of ZPP, ALAP, and ALAU tibia lead was the best predictor of hemoglobin and hematocrit.
6	Associations of Pb biomarkers and δ-ALAD & VDR with hematopoietic outcomes in Korean lead workers Lee et al. 2001 Results Lead workers with the ALAD2 allele had lower levels of ZPP and ALAP… …but there was no clear effect modification by ALAD genotype There were no consistent relations of VDR genotype with the hematopoietic outcomes… …nor any apparent effect modification by VDR genotype.
7	Associations of Pb biomarkers and δ-ALAD & VDR with hematopoietic outcomes in Korean lead workers Lee et al. 2001 Conclusions These observations suggest that lead must have a chronic, cumulative effect on hemoglobin and hematocrit levels any speculated mechanism cannot merely involve short- term plasma or target organ lead levels ALAD and VDR, identified in prior studies to be modifiers of the toxicokinetics of lead, did not clearly modify associations of measured lead biomarkers and the hematopoietic outcomes.