Associations of ALAD Genotype with Renal Function Indices in Lead Workers / 대한산업의학회지

OBJECTIVES: delta-Aminolevulinic acid dehydratase (ALAD) is a polymorphic enzyme that has two alleles, ALAD1 (ALAD1-1 as genotype) and ALAD2 (ALAD1-2 or ALAD2-2 as genotype). ALAD genotype has been reported to modify the pharmacokinetics and toxicity of lead. The authors investigated the influence of ALAD genotype polymorphism on renal function in lead workers METHODS: We studied 935 male lead workers and 87 male non-lead workers in the same industries. For cross-sectional renal indices, blood urea nitrogen (BUN), serum creatinine, serum uric acid and urine total protein were selected. Blood lead level was also measured an index of lead exposure. Information on weight, age, job duration, and smoking and drinking habits was collected. RESULTS: Whereas the mean blood lead level of lead workers was 25.4+/-10.9 microgram/dL, that of non-lead workers in the same premise was 10.1+/-2.8 microgram/dL, and the difference between the two groups was statistically significant. Whereas the prevalence of the variant allele, ALAD2 in 935 lead workers was 10.6%, that in 87 non-lead workers was 4.6%. However there was no difference of prevalence between the two groups. The mean blood lead level of subjects with ALAD1 was 23.9+/-11.4 microgram/dL, which was slightly lower than that of subjects with ALAD2 (25.8+/-10.7 microgram/dL). However, this difference was not statistically significant. After adjustment for the covariates, the subjects with ALAD2 allele were 12.8% less likely to have a median value or more of BUN than subject with ALAD1. The adjusted odds ratio was 0.59 (95% confidence interval; 0.38-0.91). After adjustment for the covariates, the subjects with ALAD2 allele were 9.3% less likely to have a median value or more of serum creatinine than subject with ALAD1. The adjusted odds ratio was 0.64 (95% confidence interval; 0.41-0.98). CONCLUSIONS: From the above results, it was found that the variant allele, ALAD2 appeared to modify the association of lead and renal function, and that ALAD2 genotype may be supportive for the protective effect of lead.

Some Renal Function Indices in Workers Occupationally Exposed to Lead / 대한산업의학회지

The influence of lead exposure on renal function was studied. Three hundred forty two male lead exposed workers who worked in 3 storage battery factories, 5 secondary smelting factories and 3 litharge making factories, and 60 male control workers who were not exposed to lead occupationally were chosen for this study. Blood lead (PbB), zinc protoporphyrin in whole blood (ZPP) and delta-aminolevulinic acid in urine (DALA) were selected as indicators of lead exposure. As indicators of renal function blood urea nitrogen(BUN) , serum creatinine(S-Cr), serum uric acid (S-UA), N-acetyl-beta-D-glucosaminidase in urine (NAG) and urine protein (U-TP) were selected. While the mean values of lead exposure indicators of lead workers were significantly different from non-exposed ones, the mean values of renal function indicators of exposed except S-UA were significantly different from non-exposed. The frequency of workers whose value of renal function indicators were over the nor mal criteria (BUN>20 mg/dl ; S-Cr>1.2 mg/dl ; S-UA>7.0 mg/dl ; NAG>8.0 U/liter; U-TP>8.0 mg/dl) by the level of lead absorption in terms of PbB, ZPP and DALA were calculated. Age adjusted odds ratio of over the normal value of BUN and NAG were statistically significant by the level of ZPP and that of BUN only showed the dose-dependant relationship. But the frequency of over the normal criteria of renal function indicators were not increased by the level of PbB and DALA. On stepwise multiple regression using renal function indicators as a dependent variable and each lead exposure indicator and age as independent variables, only BUN, NAG and U-TP were contributed by the lead exposure indicators. It was found that only NAG of renal function indices was most reliable indicator who showed dose-response relationship with lead exposure and the measurement of NAG for lead workers whose relatively high exposure is highly recommended.

A study on renal function indices in lead exposed male workers / 예방의학회지

The influence of lead exposure on renal function was studied. Eighty nine lead exposed workers who worked in 2 storage battery factories, and seventy one control workers were chosen for this study. Blood lead(pbB) and zinc protoporphyrin in whole blood(ZPP) were selected as indicators of lead exposure. As indicators of renal function, urinary N-acetyl-beta-D-glucosaminidase(NAG), blood urea nitrogen(BUN), serum creatinine(S-Cr), total protein in urine(U-Tp),and serum uric acid(S-Ua) were selected. The results obtained were as follows: 1. while the mean values of lead exposure indicators of lead workers were significantly different from non-exposed ones, the mean values of NAG, U-TP, BUN and S-Cr of renal function indicators of exposed were also significantly different from non-exposed but their mean values were all within normal limits. 2. BUN, logarithmic U-TP, logarithmic NAG and S-Cr showed statistically significant correlation with pbB. 3. The proportion of workers whose values of renal function indicators were over the normal limits(NAG7.5 U/g cr; U-TP 10.9mg/dl; BuN20 mg/dl; S-Cr1.2 mg/dl; S-Ua7.0 mg/dl) by the level of lead absorption in terms of pbB and ZPP were calculated. The proportion of workers with over the normal limits of U-TP among total workers showed the dose-response relationship. when age is adjusted, U-TP showed significantly strong dose-response relationship with the level of pbB and ZPP.