OBJECTIVETo use the data of occupational epidemiology to estimate the benchmark dose (BMD) of renal dysfunction induced by lead.

METHODSBlood lead was considered as an exposure biomarker, while urinary total protein (TP), urinary beta(2)-microglobulin (beta(2)-MG) and urinary N-Acetyl-beta-D-glucosaminidase (NAG) were considered as effect biomarkers reflecting the damage of renal function. The dichotomized (binary) data was used as effect endpoints. The BMD and BMD lower limit (BMDL) of blood lead were estimated at the 10% benchmark response using BMDS version 1.3.1.

RESULTSThere was an increased prevalence of hyper-TP-uria, hyper-beta(2)-MG-uria and hyper-NAG-uria with an increasing blood lead concentration. There was obviously dose-response relationship between blood lead and TP, beta(2)-MG and NAG, respectively. The BMD and BMDL of blood lead affecting renal function were estimated to be 323.6 - 754.3 microg/L and 274.2 - 541.5 microg/L. The BMDL of blood lead was ranged from low to high as NAG, TP and beta(2)-MG. The urinary NAG activity might be served as a sensitive biomarker in detecting early renal dysfunction.

CONCLUSIONIt should be feasible to use the BMD approach to set up the reference dose (RfD) and reference concentration (RfC). BMD approach might provide a new and better way for setting up the RfD/RfC.

Acetylglucosaminidase ; urine ; China ; epidemiology ; Clinical Chemistry Tests ; methods ; standards ; Humans ; Lead ; blood ; Lead Poisoning ; blood ; epidemiology ; urine ; Occupational Exposure ; analysis ; Prevalence ; Proteinuria ; urine ; beta 2-Microglobulin ; urine

OBJECTIVETo explore the effect of chelation therapy with succimer (DMSA) in male rabbits of moderate lead poisoning during juvenile stage.

METHODSTwenty-four 45-day-old male New Zealand rabbits were randomly divided into three groups (therapy group, TG; positive control group, PG and negative control group, NG, n=8). The TG and PG were orally exposed to lead acetate (5 mg x kg(-1) x d(-1)) for 6 weeks. Rabbits in TG were orally supplied DMSA 1050 mg/m2 in the first week and 700 mg/m2 in the next two weeks, while the other two groups wren't blood and urinary samples of all rabbits were collected per week. The tissues and organs of all rabbits were collected after 12 weeks. The blood lead levels (BLLs) were determined by atomic absorption spectrometer. The urine lead levels and the lead contents of tissue and organ were determined by inductively coupled plasma-mass spectrometry. Histopathology of tissue and organ was observed by light microscope.

RESULTSCompared with PG, the lead level in the morning urine of TG with DMSA chelating was increased significantly. The level was peaked at (1246.96 +/- 157.91) microg/L on the first day after chelating. While the base line was (40.97 +/- 1.77) microg/L before chelating. Meanwhile, the BLLs were sharply declined from (429.63 +/- 10.82) microg/L to (238.50 +/- 11.82) microg/L. The urine lead levels of TG decreased through the 3-week chelating and 3-week discontinuation. The urine lead levels of these two groups were significantly different (F=2934.35, P<0.01). Compared to each two groups in these three groups, there were significant difference (P<0.01). The authors found the reversion of BLLs in first week after stop chelating. The BLLs of PG presented the slow course of declining in the same time, were (135.50 +/- 7.09) microg/L, very close to the level of TG for (149.88 +/- 11.39) microg/L. Compared with treatment discontinuation for 3 weeks, the urine lead levels and the body weight gain of the therapy group increased more than that of PG, and the BLLs and the lead concentrations in tissues and organs decreased more than that of PG, and histopathology in the liver tissues and testicle tissues were improved.

CONCLUSIONDMSA chelating for the rodent models of moderate lead poisoning might reduce the BLLs and soft tissue lead contents quickly and effectively, decrease toxic effects of lead in a short period of time, thus alleviate the impairment of lead poisoning on tissues and organs by decreasing lead burden, and bring out improvement on the growth retardation caused by lead poisoning.

Animals ; Chelation Therapy ; Lead ; blood ; urine ; Lead Poisoning ; drug therapy ; Male ; Rabbits ; Succimer ; therapeutic use

OBJECTIVES: This study assessed the factors that have an influence on the residents exposed to heavy metals, and we utilized the findings to establish the proper management of abandoned metal mines in the future. METHODS: For a total of 258 residents who lived close to abandoned mines in Gangwon-province and Gyeonggi-province, the exposure factors and biomarkers in their blood and urine were comparatively analyzed via multiple regression analysis. RESULTS: The blood levels of lead and mercury and the cadmium levels in urine were found to be higher in the study group than that in the average Korean. For the blood levels of heavy metals according to each exposure factor, all of them were found to be significantly higher in both of the group residing for a longer period of time and the group living closer to the source of pollutants. Multiple regression analysis disclosed that all the heavy metals, except lead, in their blood were significantly reduced in proportion to the increased distance of inhabitancy from the mines. Their other biomarkers were within the normal ranges. CONCLUSIONS: We found that the distance between the residential village and the mines was a factor that affects the blood level of heavy metals in the villagers. This finding could be an important factor when developing a management model for the areas that surround abandoned metal mines. (ED note: I much like this important study.)
Biological Markers/blood/urine ; Cadmium/blood/urine ; Cluster Analysis ; Environmental Exposure/*adverse effects ; Humans ; Lead/blood/urine ; Mercury/blood/urine ; Metals, Heavy/*blood/*urine ; Mining ; Republic of Korea ; Water Pollutants, Chemical/analysis ; Water Supply/analysis

To investigate potential health risks associated with exposure to metals from an abandoned metal mine, the authors studied people living near an abandoned mine (n=102) and control groups (n=149). Levels of cadmium, copper, arsenic, lead, and zinc were measured in the air, soil, drinking water, and agricultural products. To assess individual exposure, biomarkers of each metal in blood and urine were measured. beta2-microglobulin, alpha1-microglobulin, and N-acetyl-beta-glucosaminidase and bone mineral density were measured. Surface soil in the study area showed 2-10 times higher levels of metals compared to that of the control area. Metal concentrations in the groundwater and air did not show any notable differences between groups. Mean concentrations of cadmium and copper in rice and barley from the study area were significantly higher than those of the control area (p<0.05). Geometric means of blood and urine cadmium in the study area were 2.9 microgram/L and 1.5 microgram/g Cr, respectively, significantly higher than those in the control area (p<0.05). There were no differences in the levels of urinary markers of early kidney dysfunction and bone mineral density. The authors conclude that the residents near the abandoned mine were exposed to higher levels of metals through various routes.
Aged ; Cadmium/*blood/*urine ; Copper/blood/urine ; Environmental Exposure ; *Environmental Monitoring ; Female ; *Food Contamination ; Hordeum ; Humans ; Korea ; Lead/blood/urine ; Male ; Middle Aged ; *Mining ; Oryza sativa ; Risk Factors ; Soil Pollutants/analysis ; Water Pollutants, Chemical/analysis ; Zinc/blood/urine

Concentrations of heavy metals exceed safety thresholds in the soil near Janghang Copper Refinery, a smelter in Korea that operated from 1936 to 1989. This study was conducted to evaluate the level of exposure to toxic metals and the potential effect on health in people living near the smelter. The study included 572 adults living within 4 km of the smelter and compared them with 413 controls group of people living similar lifestyles in a rural area approximately 15 km from the smelter. Urinary arsenic (As) level did not decrease according to the distance from the smelter, regardless of gender and working history in smelters and mines. However, in subjects who had no occupational exposure to toxic metals, blood lead (Pb) and cadmium (Cd) and urinary Cd decreased according to the distance from the smelter, both in men and women. Additionally, the distance from the smelter was a determinant factor for a decrease of As, Pb, and Cd in multiple regression models, respectively. On the other hands, urinary Cd was a risk factor for renal tubular dysfunction in populations living near the smelter. These results suggest that Janghang copper smelter was a main contamination source of As, Pb, and Cd, and populations living near the smelter suffered some adverse health effects as a consequence. The local population should be advised to make efforts to reduce exposure to environmental contaminants, in order to minimize potential health effects, and to pay close attention to any health problems possibly related to toxic metal exposure.
Acetylglucosaminidase/urine ; Adult ; Aged ; Arsenic/*urine ; Bone Density ; Cadmium/*blood ; Case-Control Studies ; Chemical Industry ; Creatinine/urine ; *Environmental Exposure ; Environmental Pollutants/*analysis/blood/urine ; Female ; Humans ; Lead/*blood ; Male ; Middle Aged ; Regression Analysis ; Republic of Korea ; Spectrophotometry, Atomic

BACKGROUND: Previous studies have suggested that exposures to heavy metals (arsenic, cadmium, lead, and selenium) may be associated with differences in blood pressure. However, the findings of these studies have been inconsistent. This study was performed to examine the associations between urinary heavy metal concentrations and blood pressure among residents of four Asian countries (Bangladesh, Indonesia, Nepal, and Vietnam). METHODS: This cross-sectional study examined 1899 adults in four Asian countries. Urinary concentrations of heavy metals were measured by inductively coupled plasma mass spectrometry. A questionnaire survey was administered regarding individual characteristics. Anthropometric measurements (height and weight) were performed. Systolic and diastolic blood pressures were measured after a short rest. Multiple linear regression models were applied to investigate associations between urinary heavy metal concentrations and blood pressure after adjustments for age, sex, and body mass index. RESULTS: The geometric means of the urinary concentrations of arsenic, cadmium, lead, and selenium were 84.6, 0.885, 2.09, and 16.5 μg/g creatinine, respectively. The urinary arsenic concentrations were slightly higher than those typically reported in non-polluted populations, while urinary cadmium, lead, and selenium concentrations were equivalent or slightly lower. The urinary lead concentrations were positively associated with both systolic and diastolic blood pressure, but urinary selenium concentrations were negatively associated with them. CONCLUSIONS Variations in the urinary concentrations of lead and selenium were associated with blood pressure at low levels of exposure/intake.
Adult ; Arsenic/urine* ; Bangladesh ; Blood Pressure ; Cadmium/urine* ; Cross-Sectional Studies ; Environmental Exposure ; Female ; Humans ; Indonesia ; Lead/urine* ; Linear Models ; Male ; Metals, Heavy/urine* ; Middle Aged ; Nepal ; Selenium/urine* ; Vietnam

OBJECTIVETo observe the effect of paiqian chewing tablet (PQCT) on lead discharging and health in children.

METHODSAdopting self-control and inter-group control method, 94 children with blood lead level exceeding 100 microg/L were randomly divided into the observed group and the control group. The observation period for both groups was 30 days.

RESULTSAt the 20th and 30th day of treatment, the urinary lead output in the observed group was significantly higher than that in the control group (P < 0.05, P < 0.01), and showed significant difference as compared with that before treatment (P < 0.05). Besides, the total amount of urinary lead discharging in the observed group was significantly more than that in the control group (P < 0.05).

CONCLUSIONPQCT has markedly lead discharging improvement action with no influence on urinary calcium and zinc excretion. As all the routine indexes of blood and urine ranged within the normal extent, it demonstrated that PQCT was harmless to the health of observed individual.

Child ; Double-Blind Method ; Drugs, Chinese Herbal ; therapeutic use ; Female ; Humans ; Lead ; blood ; urine ; Lead Poisoning ; drug therapy ; Male ; Phytotherapy ; Tablets

OBJECTIVETo evaluate the levels of lead (Pb) and cadmium (Cd) in blood and urine among general population in China, and thereby analyze their prevalent features.

METHODSA total of 18 120 subjects from general population aged 6-60 years were recruited from 24 districts in 8 provinces in eastern, central and western China mainland from 2009 to 2010, by cluster random sampling method. The blood samples and urine samples of these people were collected. The questionnaire survey was used to collect the information of the living environment and health conditions.Inductive coupled plasma mass spectrometry was applied to test the Pb and Cd levels in the samples, and the distribution of Pb and Cd in blood and urine for different ages, genders, areas and life habits were then analyzed.

RESULTSAmong the general population in China, the geometric mean (GM) of blood Pb concentration was 34.9 µg/L; the GM of blood Pb in male and female groups were 40.1 and 30.4 µg/L (Z = -28.05, P < 0.05), respectively; the GM from eastern, central and western China were 31.2, 38.8 and 58.9 µg/L (χ(2) = 1 483.33, P < 0.05) , respectively. The GM of urine Pb of the whole population was 1.05 µg/L;while the GM in male and female groups were 1.06 µg/L and 1.05 µg/L (Z = -0.73, P > 0.05) , respectively;the values from eastern, central and western China were 0.76, 2.85 and 3.22 µg/L (χ(2) = 1 982.11, P < 0.05), respectively. The GM of blood Cd concentration among general population was 0.49 µg/L; and the values in male and female group were 0.60 and 0.41 µg/L (Z = -11.79, P < 0.05) , respectively; the GM from eastern, central and western China were 0.45, 0.65 and 0.67 µg/L (χ(2) = 69.87, P < 0.05), respectively; the GM of urine Cd concentration of the whole population was 0.28 µg/L, while the GM in male and female groups were 0.29 and 0.28 µg/L (Z = -3.86, P < 0.05), respectively; the values from eastern, central and western China were 0.29,0.42 and 0.18 µg/L (χ(2) = 402.76, P < 0.05), respectively. the Spearman's rank correlation coefficient for Cd in blood and Cd in urine was 0.22, for Pb in blood and Pb in urine was 0.21. Both the correlations were statistic significant (P < 0.05).

CONCLUSIONThe Pb and Cd levels in blood and urine were relatively higher among general population in China varying by gender and area. There were positive correlations between Pb and Cd levels in blood and those in urine.

Adolescent ; Adult ; Cadmium ; blood ; urine ; Child ; China ; epidemiology ; Cross-Sectional Studies ; Environmental Exposure ; Female ; Humans ; Lead ; blood ; urine ; Male ; Middle Aged ; Sentinel Surveillance ; Young Adult

OBJECTIVETo observe the effect of long-term external use of Goupi Gao on renal function and lead accumulation in rats.

METHODRats were externally administered with Goupi Gao at different doses (7, 3.5 and 1.75 g x kg(-1)) for 90 d. At 45 days and 90 days after administration, the renal indicator, levels of blood urea nitrogen (BU) and creatinine (Cr) in serum, beta2-microglobulin (beta2-MG) and N-acetyl-beta-D-glucosaminidase (NAG) in urine were determined. Lead content in kidneys was detected by atomic absorption spectrometry.

RESULTA 90-day administration with Goupi Gao significantly enhanced the renal indicator, levels of NAG in urine and lead content in renal, when compared with the normal rats. However, the levels of BUN and beta2-MG as well as renal pathology in Goupi Gao treated rats were not obviously changed.

CONCLUSIONConsecutive administration of Goupi Gao for 90 days can increase the renal indicator and levels of NAG in urine, enhance the accumulation of lead in renal, but with no effect on excretory function of kidneys and organic changes.

Acetylglucosaminidase ; urine ; Animals ; Blood Urea Nitrogen ; Creatinine ; blood ; Drugs, Chinese Herbal ; administration & dosage ; toxicity ; Female ; Kidney ; drug effects ; metabolism ; pathology ; Lead ; analysis ; metabolism ; Male ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Spectrophotometry, Atomic ; beta 2-Microglobulin ; urine

OBJECTIVETo assess the risk of renal dysfunction caused by occupational lead exposure through epidemiological investigation.

METHODSThe workers in a battery factory were selected as the subjects for the exposure and effect assessment. The occupational environmental monitoring data was collected and used to calculate the total external dose of lead. The relationship between external dose and internal dose of lead was analyzed. The external dose, blood lead (BPb) and urinary lead (UPb) were used as exposure biomarkers while the urinary N-acetyl-D-glucosaminidase (UNAG), and urinary albumin (UALB) were used as the effect biomarkers for the renal dysfunction caused by lead. Software of BMDS (BMDS 11311) was used to calculate BMD.

RESULTSThe external and internal does of lead was positively correlated (BPb: r = 0.466, P < 0.01; UPb: r = 0.383, P < 0.01). The levels of BPb, UPb in exposure group (654.03 microg/L, 143.45 microg/g Cr) were significantly higher than those in the control group (57.12 microg/L, 7.20 microg/g Cr), so were UALB, UNAG; in addition, all of them presented significant dose-response relationship. The BPb BMD of UALB, UNAG were 607.76, 362.56 microg/L respectively and the UPb BMD of UALB, UNAG were 117.79, 78.79 microg/gCr respectively.

CONCLUSIONOccupational lead exposure can cause renal dysfunction, which presents dose-response relationship; the risk assessment of renal dysfunction caused by occupational lead exposure is performed by BMD calculation of BPb and UPb.

Adolescent ; Adult ; Biomarkers ; blood ; urine ; Environmental Monitoring ; Female ; Humans ; Kidney ; drug effects ; Kidney Diseases ; chemically induced ; Lead ; blood ; urine ; Male ; Middle Aged ; Occupational Exposure ; Risk Assessment ; Surveys and Questionnaires ; Young Adult