title: Benchmark dose approach for low-level lead induced haematogenesis inhibition and associations of childhood intelligences with ALAD activity and ALA levels.
abstract: Lead (Pb) levels, delta-aminolevulinic acid dehydratase (ALAD) activities, zinc protoporphyrin (ZPP) levels in blood, and urinary delta-aminolevulinic acid (ALA) and coproporphyrin (CP) concentrations were measured for 318 environmental Pb exposed children recruited from an area of southeast China. The mean of blood lead (PbB) levels was 75.0μg/L among all subjects. Benchmark dose (BMD) method was conducted to present a lower PbB BMD (lower bound of BMD) of 32.4μg/L (22.7) based on ALAD activity than those based on the other three haematological indices, corresponding to a benchmark response of 1%. Childhood intelligence degrees were not associated significantly with ALAD activities or ALA levels. It was concluded that blood ALAD activity is a sensitive indicator of early haematological damage due to low-level Pb exposures for children.
authors.affiliation: Department of Epidemiology & Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China. lwq95@126.com
authors.forename: Q
authors.initials: Q
authors.lastname: Wang
authors.forename: L X
authors.initials: LX
authors.lastname: Ye
authors.forename: H H
authors.initials: HH
authors.lastname: Zhao
authors.forename: J W
authors.initials: JW
authors.lastname: Chen
authors.forename: Y K
authors.initials: YK
authors.lastname: Zhou
mesh_terms: D000622:Aminolevulinic Acid / Q000652:urine*; D019985:Benchmarking; D015415:Biomarkers / Q000097:blood / Q000378:metabolism / Q000652:urine; D002648:Child; D003306:Coproporphyrins / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004785:Environmental Pollutants / Q000592:standards / Q000633:toxicity*; D005260:Female; D006410:Hematopoiesis / Q000187:drug effects*; D006801:Humans; D007360:Intelligence / Q000187:drug effects*; D007854:Lead / Q000592:standards / Q000633:toxicity*; D008297:Male; D000623:Porphobilinogen Synthase / Q000378:metabolism*; D011524:Protoporphyrins / Q000097:blood
chemical_list: D015415:Biomarkers; D003306:Coproporphyrins; D004785:Environmental Pollutants; D011524:Protoporphyrins; C017803:zinc protoporphyrin; D007854:Lead; C031467:coproporphyrin I; D000622:Aminolevulinic Acid; D000623:Porphobilinogen Synthase