ILO Home
Go to the home page
Site map | Contact us Franšais | Espa˝ol

CISDOC database

Document ID (ISN)106813
CIS number 07-856
ISSN - Serial title 0160-2748 - Neurotoxicology
Year 2004
Convention or series no.
Author(s) Chia S.E., Yap E., Chia K.S.
Title δ-Aminolevulinic acid dehydratase (ALAD) polymorphism and susceptibility of workers exposed to inorganic lead and its effects on neurobehavioral functions
Bibliographic information 2004, Vol.25, p.1041-1047. 20 ref.
Internet access 07-0856.pdf [in English]
Abstract This cross-sectional study was carried out to determine the frequency of δ-aminolevulinic acid dehydratase (ALAD) polymorphisms among a total of 120 ethnic Chinese, Malay and Indian male workers who were exposed to low to medium levels of inorganic lead. The association between ALAD1 and ALAD2 genotypes and neurobehavioural functions among these workers was also investigated. Blood and urine were collected to determine the ALAD genotypes, blood lead levels, ALAD, and urinary δ-aminolevulinic acid (ALA). ALAD1-1 was the predominant genotype for all three ethnic groups while ALAD2-2 was the rarest. The distribution of ALAD1-2 was higher among Malays (76.7%) and Indians (14.3%), compared to Chinese (3.6%). Workers with ALAD1-1 genotypes had significantly higher urinary ALA and significantly poorer neurobehavioral scores than those with ALAD1-2/2-2 genotypes. The ALAD2 allele may exert protective measures against the neurotoxic effects of lead.
Descriptors (primary) neurotoxic effects; individual susceptibility; ALAD; lead and compounds
Descriptors (secondary) race-linked differences; airborne dust; nervous function tests; Singapore; determination in urine; lead oxide; aminolevulinic acid; cross-sectional study; determination in blood; lead
Document type D - Periodical articles
Country / State or ProvinceSingapore
Subject(s) Toxic and dangerous substances
Broad subject area(s) Chemical safety
Browse category(ies) Inorganic substances
Diseases of the nervous system
Lead and compounds