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Lombaert N, Gilles M, Verougstraete V. Cadmium Monitoring at the Workplace: Effectiveness of a Combination of Air- and Biomonitoring. TOXICS 2023; 11:354. [PMID: 37112581 PMCID: PMC10147057 DOI: 10.3390/toxics11040354] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 03/30/2023] [Accepted: 04/06/2023] [Indexed: 06/19/2023]
Abstract
Inhalation exposure to cadmium at the workplace has been associated with an increased risk of lung cancer and non-cancer respiratory effects. To ensure levels of cadmium remain below effect levels, air quality is monitored and regulations specifying an air limit value are implemented. The EU Carcinogens and Mutagens Directive of 2019 recommended values for the inhalable fraction and the respirable fraction but the latter only for a transitional period. Cadmium exposure has also been associated with systemic effects, following its storage in the kidneys and due to its long half-life. The accumulation of cadmium occurs via different exposure routes and from different sources, including workplace dust and fumes, food, and smoking. Biomonitoring (in blood, urine) has been identified as the most appropriate method to follow up cumulative exposure and total cadmium body burden, as it conveniently reflects intakes by all routes. However, it is not systematically implemented. This paper has a double objective: first, proposing a possible limit value for the respirable fraction, using an approach integrating epidemiological data. Secondly, demonstrating that the implementation of both air and biological limit values is key to protecting workers' health in occupational settings. The paper summarizes the current knowledge on cadmium health effects and how biomarkers reflect those. It presents an approach to derive a respirable value, using recent human data, and describes how the combination of air monitoring and biomonitoring is applied by the EU industry to protect the workforce. While a respirable fraction value helps protect workers against local respiratory adverse health effects, air monitoring alone is not sufficient to protect workers against systemic effects of cadmium. Therefore, complementary biomonitoring and the implementation of a biological limit value is recommended.
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Affiliation(s)
- Noömi Lombaert
- International Cadmium Association, 1150 Brussels, Belgium
- International Zinc Association, Reach Cadmium Consortium, 1150 Brussels, Belgium
| | - Mik Gilles
- International Cadmium Association, 1150 Brussels, Belgium
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Could Kallikrein-Related Serine Peptidase 3 Be an Early Biomarker of Environmental Exposure in Young Women? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18168833. [PMID: 34444582 PMCID: PMC8392638 DOI: 10.3390/ijerph18168833] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 08/18/2021] [Accepted: 08/19/2021] [Indexed: 11/16/2022]
Abstract
Bisphenols and phthalates affect androgen receptor-mediated signaling that directly regulates Kallikrein-Related serine Peptidase 3 (KLK3) secretion, indicating that environmental factors may play a role in KLK3 secretion. With the aim of obtaining preliminary data on whether KLK3 could serve as an early marker of environmental pollution effects, in 61 and 58 healthy women living in a high environmental impact (HEI) and low environmental impact (LEI) area, respectively, serum KLK3 levels at different phases of menstrual cycle were measured. KLK3 values resulted in always being higher in the HEI group with respect to the LEI group. These differences were particularly relevant in the ovulatory phase (cycle day 12°–13°) of the menstrual cycle. The differences in KLK3 values during the three phases of the menstrual cycle were significant in the LEI group differently from the HEI group. In addition, higher progesterone levels were observed in the LEI group with respect to the HEI group in the luteal phase, indicating an opposite trend of KLK3 and progesterone in this phase of the menstrual cycle. Although changes in KLK3 could also depend on other factors, these preliminary data could be an early indication of an expanding study of the role of biomarkers in assessing early environmental effects for female reproductive health.
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The Source and Pathophysiologic Significance of Excreted Cadmium. TOXICS 2019; 7:toxics7040055. [PMID: 31635341 PMCID: PMC6958378 DOI: 10.3390/toxics7040055] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 10/10/2019] [Accepted: 10/16/2019] [Indexed: 12/23/2022]
Abstract
In theory, the identification of the source of excreted cadmium (Cd) might elucidate the pathogenesis of Cd-induced chronic kidney disease (CKD). With that possibility in mind, we studied Thai subjects with low, moderate, and high Cd exposure. We measured urine concentrations of Cd, ([Cd]u); N-acetyl-β-d-glucosaminidase, a marker of cellular damage ([NAG]u); and β2-microglobulin, an indicator of reabsorptive dysfunction ([β2MG]u). To relate excretion rates of these substances to existing nephron mass, we normalized the rates to creatinine clearance, an approximation of the glomerular filtration rate (GFR) (ECd/Ccr, ENAG/Ccr, and Eβ2MG/Ccr). To link the loss of intact nephrons to Cd-induced tubular injury, we examined linear and quadratic regressions of estimated GFR (eGFR) on ECd/Ccr, eGFR on ENAG/Ccr, and ENAG/Ccr on ECd/Ccr. Estimated GFR varied inversely with both ratios, and ENAG/Ccr varied directly with ECd/Ccr. Linear and quadratic regressions of Eβ2MG/Ccr on ECd/Ccr and ENAG/Ccr were significant in moderate and high Cd-exposure groups. The association of ENAG/Ccr with ECd/Ccr implies that both ratios depicted cellular damage per surviving nephron. Consequently, we infer that excreted Cd emanated from injured tubular cells, and we attribute the reduction of eGFR to the injury. We suggest that ECd/Ccr, ENAG/Ccr, and eGFR were associated with one another because each parameter was determined by the tubular burden of Cd.
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Sasaki T, Horiguchi H, Arakawa A, Oguma E, Komatsuda A, Sawada K, Murata K, Yokoyama K, Matsukawa T, Chiba M, Omori Y, Kamikomaki N. Hospital-based screening to detect patients with cadmium nephropathy in cadmium-polluted areas in Japan. Environ Health Prev Med 2019; 24:8. [PMID: 30684957 PMCID: PMC6347770 DOI: 10.1186/s12199-019-0762-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 01/16/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In health examinations for local inhabitants in cadmium-polluted areas, only healthy people are investigated, suggesting that patients with severe cadmium nephropathy or itai-itai disease may be overlooked. Therefore, we performed hospital-based screening to detect patients with cadmium nephropathy in two core medical institutes in cadmium-polluted areas in Akita prefecture, Japan. METHODS Subjects for this screening were selected from patients aged 60 years or older with elevated serum creatinine levels and no definite renal diseases. We enrolled 35 subjects from a hospital in Odate city and 22 from a clinic in Kosaka town. Urinary ß2-microglobulin and blood and urinary cadmium levels were measured. RESULTS The criteria for renal tubular dysfunction and the over-accumulation of cadmium were set as a urinary ß2-microglobulin level higher than 10,000 μg/g cr. and a blood cadmium level higher than 6 μg/L or urinary cadmium level higher than 10 μg/g cr., respectively. Subjects who fulfilled both criteria were diagnosed with cadmium nephropathy. Six out of 57 patients (10.5% of all subjects) had cadmium nephropathy. CONCLUSIONS This hospital-based screening is a very effective strategy for detecting patients with cadmium nephropathy in cadmium-polluted areas, playing a complementary role in health examinations for local inhabitants. REGISTRATION NUMBER No. 6, date of registration: 6 June, 2010 (Akita Rosai Hospital), and No. 1117, date of registration: 26 December, 2013 (Akita University).
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Affiliation(s)
- Toru Sasaki
- Department of Internal Medicine, Akita Rosai Hospital, Japan Organization of Occupational Health and Safe, Akita, 018-5604, Japan.,Fukunaga Clinic, Akita, 018-5334, Japan
| | - Hyogo Horiguchi
- Department of Hygiene, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa, 010-8543, Japan. .,Department of Environmental Health Sciences, Akita University, Graduate School of Medicine, Akita, 010-8543, Japan. .,Department of Environmental and Preventive Medicine, School of Medicine, Jichi Medical University, Tochigi, 329-0498, Japan.
| | | | - Etsuko Oguma
- Department of Hygiene, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa, 010-8543, Japan.,Department of Environmental Health Sciences, Akita University, Graduate School of Medicine, Akita, 010-8543, Japan.,Department of Environmental and Preventive Medicine, School of Medicine, Jichi Medical University, Tochigi, 329-0498, Japan
| | - Atsushi Komatsuda
- Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, 010-8543, Japan
| | - Kenichi Sawada
- Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, 010-8543, Japan
| | - Katsuyuki Murata
- Department of Environmental Health Sciences, Akita University, Graduate School of Medicine, Akita, 010-8543, Japan
| | - Kazuhito Yokoyama
- Department of Epidemiology and Environmental Health, Juntendo University Faculty of Medicine, Tokyo, 113-8421, Japan
| | - Takehisa Matsukawa
- Department of Epidemiology and Environmental Health, Juntendo University Faculty of Medicine, Tokyo, 113-8421, Japan
| | - Momoko Chiba
- Department of Epidemiology and Environmental Health, Juntendo University Faculty of Medicine, Tokyo, 113-8421, Japan
| | - Yuki Omori
- Department of Hygiene, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa, 010-8543, Japan.,Department of Epidemiology and Environmental Health, Juntendo University Faculty of Medicine, Tokyo, 113-8421, Japan
| | - Norihiro Kamikomaki
- Department of Internal Medicine, Akita Rosai Hospital, Japan Organization of Occupational Health and Safe, Akita, 018-5604, Japan.,Department of Emergency, Saiseikai Utsunomiya Hospital, Utsunomiya, 321-0974, Japan
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Urinary enzymatic markers (N-acetyl-beta-D-glucosaminidase) in assessing the tubulointerstitial compartment in chronic glomerulonephritis related to odontogenic foci. Wien Klin Wochenschr 2015; 128:102-8. [PMID: 26377174 DOI: 10.1007/s00508-015-0841-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 07/29/2015] [Indexed: 12/21/2022]
Abstract
Chronic glomerulonephritis is related to focus infection. Odontogenic foci are frequently involved in glomerulonephritis. The relationship with the odontogenic focus infection can be demonstrated by the occurrence or aggravation of the symptoms of glomerulonephritis: proteinuria, haematuria, high blood pressure and oedema. Glomerular impairment in glomerulonephritis occurs together with inflammatory alterations of the tubulointerstitial compartment that can play an important part in the evolution of the disease. Tubular urinary markers can indicate the activation of this compartment during an infection of a focus, an odontogenic focus in our study.The paper aims at demonstrating the relationship between the odontogenic focus infection and tubulointerstitial lesions, assessed by a tubular urinary marker, N-acetyl beta-D glucosaminidase (NAG).We investigated the urinary N-acetyl beta-D glucosaminidase of 20 patients with chronic glomerulonephritis who presented odontogenic focus infections, comparing them with patients with chronic glomerulonephritis without odontogenic foci and of 20 controls, clinically healthy persons.Chronic glomerulonephritis patients with odontogenic focus infection presented clearly increased values as compared to clinically healthy control persons of urinary N-acetyl beta-D glucosaminidase.These patients underwent surgical intervention on the odontogenic focus under antibacterial prophylactic treatment. In 75% cases, the values of N-acetyl beta-D glucosaminidase diminished, indicating the favourable effect of the treatment of the odontogenic focus on the tubulointerstitial compartment in patients with chronic glomerulonephritis. In 25% cases this therapeutic treatment was associated with an increase of the values of urinary N-acetyl beta-D glucosaminidase, expressing its unfavourable effect on chronic glomerulonephritis.Urinary N-acetyl beta-D glucosaminidase indicated an etiopathogenetic relationship between the odontogenic focus and the tubulointerstitial compartment in chronic glomerulonephritis.
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Quercetin Protects against Cadmium-Induced Renal Uric Acid Transport System Alteration and Lipid Metabolism Disorder in Rats. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012; 2012:548430. [PMID: 22690247 PMCID: PMC3368504 DOI: 10.1155/2012/548430] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Accepted: 03/26/2012] [Indexed: 11/17/2022]
Abstract
Hyperuricemia and dyslipidemia are involved in Cd nephrotoxicity. The aim of this study was to determine the effect of quercetin, a dietary flavonoid with anti-hyperuricemic and anti-dyslipidemic properties, on the alteration of renal UA transport system and disorder of renal lipid accumulation in 3 and 6 mg/kg Cd-exposed rats for 4 weeks. Cd exposure induced hyperuricemia with renal XOR hyperactivity and UA excretion dysfunction in rats. Simultaneously, abnormal expression levels of renal UA transport-related proteins including RST, OAT1, MRP4 and ABCG2 were observed in Cd-exposed rats with inhibitory activity of renal Na+-K+-ATPase. Furthermore, Cd exposure disturbed lipid metabolism with down-regulation of AMPK and its downstream targets PPARα, OCTN2 and CPT1 expressions, and up-regulation of PGC-1β and SREBP-1 expressions in renal cortex of rats. We had proved that Cd-induced disorder of renal UA transport and production system might have cross-talking with renal AMPK-PPARα/PGC-1β signal pathway impairment, contributing to Cd nephrotoxicity of rats. Quercetin was found to be effective against Cd-induced dysexpression of RST and OAT1 with XOR hyperactivity and impairment of AMPK-PPARα/PGC-1β signal pathway, resulting in renal lipid accumulation reduction of rats.
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Haddam N, Samira S, Dumont X, Taleb A, Lison D, Haufroid V, Bernard A. Confounders in the assessment of the renal effects associated with low-level urinary cadmium: an analysis in industrial workers. Environ Health 2011; 10:37. [PMID: 21569589 PMCID: PMC3118317 DOI: 10.1186/1476-069x-10-37] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Accepted: 05/14/2011] [Indexed: 05/19/2023]
Abstract
BACKGROUND Associations of proteinuria with low-level urinary cadmium (Cd) are currently interpreted as the sign of renal dysfunction induced by Cd. Few studies have considered the possibility that these associations might be non causal and arise from confounding by factors influencing the renal excretion of Cd and proteins. METHODS We examined 184 healthy male workers (mean age, 39.5 years) from a zinc smelter (n = 132) or a blanket factory (n = 52). We measured the concentrations of Cd in blood (B-Cd) and the urinary excretion of Cd (U-Cd), retinol-binding protein (RBP), protein HC and albumin. Associations between biomarkers of metal exposure and urinary proteins were assessed by simple and multiple regression analyses. RESULTS The medians (interquartile range) of B-Cd (μg/l) and U-Cd (μg/g creatinine) were 0.80 (0.45-1.16) and 0.70 (0.40-1.3) in smelter workers and 0.66 (0.47-0.87) and 0.55 (0.40-0.90) in blanket factory workers, respectively. Occupation had no influence on these values, which varied mainly with smoking habits. In univariate analysis, concentrations of RBP and protein HC in urine were significantly correlated with both U-Cd and B-Cd but these associations were substantially weakened by the adjustment for current smoking and the residual influence of diuresis after correction for urinary creatinine. Albumin in urine did not correlate with B-Cd but was consistently associated with U-Cd through a relationship, which was unaffected by smoking or diuresis. Further analyses showed that RBP and albumin in urine mutually distort their associations with U-Cd and that the relationship between RBP and Cd in urine was almost the replicate of that linking RBP to albumin CONCLUSIONS Associations between proteinuria and low-level urinary Cd should be interpreted with caution as they appear to be largely driven by diuresis, current smoking and probably also the co-excretion of Cd with plasma proteins.
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Affiliation(s)
- Nahida Haddam
- Laboratory of Medical Toxicology, Faculty of Medicine, University Abou Bekr Belkaid, Tlemcen, Algeria
- Institute of Biology, Faculty of Science, University Abou Bekr Belkaid, Tlemcen, Algeria
| | - Sekkal Samira
- Laboratory of Medical Toxicology, Faculty of Medicine, University Abou Bekr Belkaid, Tlemcen, Algeria
| | - Xavier Dumont
- Unit of Toxicology and Applied Pharmacology, Catholic University of Louvain, Brussels, Belgium
| | - Abdesselem Taleb
- Laboratory of Medical Toxicology, Faculty of Medicine, University Abou Bekr Belkaid, Tlemcen, Algeria
| | - Dominique Lison
- Unit of Toxicology and Applied Pharmacology, Catholic University of Louvain, Brussels, Belgium
| | - Vincent Haufroid
- Unit of Toxicology and Applied Pharmacology, Catholic University of Louvain, Brussels, Belgium
| | - Alfred Bernard
- Unit of Toxicology and Applied Pharmacology, Catholic University of Louvain, Brussels, Belgium
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Chaumont A, De Winter F, Dumont X, Haufroid V, Bernard A. The threshold level of urinary cadmium associated with increased urinary excretion of retinol-binding protein and beta 2-microglobulin: a re-assessment in a large cohort of nickel-cadmium battery workers. Occup Environ Med 2011; 68:257-64. [PMID: 20935291 PMCID: PMC3060309 DOI: 10.1136/oem.2009.054122] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/23/2010] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To evaluate the threshold value of urinary cadmium (CdU) for renal dysfunction on the basis of relationships unconfounded by protein degradation, diuresis and the renal effects associated with chronic smoking. Methods We studied 599 workers (451 men, mean age 45.4 years) who were employed in four nickel-cadmium battery plants for 18.8 years on average. After adjustment for covariates by multiple regression, the CdU threshold values for increased concentrations of retinol-binding protein (RBPU) and b(2)-microglobulin (b(2)-mU) were assessed by logistic regression and benchmark dose analyses using as referents workers with CdU<1 μg/g creatinine. Results Relationships between urinary proteins and CdU (μg/g creatinine) were influenced by sex, age, diuresis and especially smoking. When considering all workers, odds for abnormal RBPU and b(2)-mU were significantly increased from CdU of 6-10 and >10, respectively. The benchmark dose (BMD5) and the benchmark dose lower limit (BMDL5) for a 5% excess in the background prevalence of abnormal RBPU and b(2)-mU were estimated at 5.1/3.0 and 9.6/5.9. When excluding ever smokers, odds for abnormal RBPU and b(2)-mU were both increased only among workers with CdU>10 (OR, 21.8, 95% CI, 6.4-74.4 and OR, 15.1, 95% CI, 3.6-63.1, respectively). In never smokers, these BMD5/BMDL5 of CdU were estimated at 12.6/6.6 and 12.2/5.5 while in ever smokers they were 6.2/4.9 and 4.3/3.5. Conclusions On the basis of associations undistorted by smoking and adjusted for covariates, the BMDL5 of CdU for low-molecular-weight proteinuria induced by occupational exposure to Cd can be reliably estimated between 5.5 and 6.6 μg/g creatinine.
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Affiliation(s)
- Agnès Chaumont
- Unit of Toxicology and Applied Pharmacology, Catholic University of Louvain, Avenue E Mounier 53.02, Brussels B-1200, Belgium
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Apostolova MD, Christova T, Templeton DM. Involvement of gelsolin in cadmium-induced disruption of the mesangial cell cytoskeleton. Toxicol Sci 2005; 89:465-74. [PMID: 16280379 DOI: 10.1093/toxsci/kfj035] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Cadmium (Cd2+) is known to cause a selective disruption of the filamentous actin cytoskeleton in the smooth muscle-like renal mesangial cell. We examined the effect of Cd2+ on the distribution of the actin-severing protein, gelsolin. Over 8 h, CdCl2 (10 microM) caused a progressive shift of gelsolin from a diffuse perinuclear and cytoplasmic distribution to a pattern decorating F-actin filaments. Over this time filaments were decreased in number in many cells, and membrane ruffling was initiated. Western blotting and 125I-F-actin gel overlays demonstrated an increase in actin-binding gelsolin activity in the cytoskeletal fraction of cell extracts following Cd2+ treatment. In in vitro polymerization assays, gelsolin acted as a nucleating factor and increased the rate of polymerization. Cytosolic extracts also increased the polymerization rate. Addition of Cd2+ together with gelsolin further increased the rate of polymerization. Gelsolin enhanced depolymerization of purified actin, and Cd2+ partially suppressed this effect. However, cytoskeletal extracts from Cd2+-treated cells also markedly increased depolymerization, suggesting further that Cd2+ may activate cellular component(s) such as gelsolin for actin binding. We conclude that a major effect of Cd2+ on the mesangial cell cytoskeleton is manifest through activating the association of gelsolin with actin, with gelsolin's severing properties predominating under conditions found in Cd2+-treated cells.
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Affiliation(s)
- Margarita D Apostolova
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, M5S 1A8, Canada
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Chia SE, Zhou H, Tham MT, Yap E, Dong NV, Tu NH, Chia KS. Possible influence of delta-aminolevulinic acid dehydratase polymorphism and susceptibility to renal toxicity of lead: a study of a Vietnamese population. ENVIRONMENTAL HEALTH PERSPECTIVES 2005; 113:1313-7. [PMID: 16203232 PMCID: PMC1281272 DOI: 10.1289/ehp.7904] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We examined six newly identified polymorphisms in the delta-aminolevulinic acid dehydratase (ALAD) single-nucleotide polymorphisms (SNPs) to determine if these SNPs could modify the relationship between blood lead (PbB) and some renal parameters. This is a cross-sectional study of 276 lead-exposed workers in Vietnam. All workers were measured for PbB, urinary retinol-binding protein (URBP), urinary alpha1-microglobulin (Ualpha1m), urinary beta2-microglobulin (Ubeta 2m), urinary N-acetyl-beta -d-glucosaminidase (NAG), urinary aminolevulinic acid (ALAU), serum alpha1-microglobulin (Salpha1m), serum beta2-microglobulin (Sbeta 2m), and urinary albumin (Ualb). The six SNPs were Msp and Rsa in exon 4, Rsa39488 in exon 5, HpyIV and HpyCH4 in intron 6, and Sau3A in intron 12. Analysis of covariance (ANCOVA) with interaction of PbB times SNPs were applied to examine modifying effect of the SNPs on the association of renal parameters and PbB, adjusting for potential confounders of age, gender, body mass index, and exposure duration. HpyCH4 was found to be associated with certain renal parameters. For HpyCH4 1-1, an increase of 1 microg/dL PbB caused an increase of 1.042 mg/g creatinine (Cr) U alpha1m, 1.069 mg/g Cr Ubeta 2m, 1.038 mg/g Cr URBP, and 1.033 mg/g Cr Ualb, whereas in HpyCH4 1-2, an increase of 1 microg/dL PbB resulted in an increase of only 1.009 mg/g Cr Ualpha1m, 1.012 mg/g Cr Ubeta 2m, 1.009 mg/g Cr URBP, and 1.007 mg/g Cr Ualb. HpyCH4 SNP appeared to modify the lead toxicity to kidney with wild-type allele being more susceptible than variants. The mechanism for this effect is not clear. Further studies are needed to confirm this observation.
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Affiliation(s)
- Sin Eng Chia
- Department of Community, Occupational and Family Medicine, National University of Singapore, Singapore, Republic of Singapore
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Hirano S, Sun X, DeGuzman CA, Ransom RF, McLeish KR, Smoyer WE, Shelden EA, Welsh MJ, Benndorf R. p38 MAPK/HSP25 signaling mediates cadmium-induced contraction of mesangial cells and renal glomeruli. Am J Physiol Renal Physiol 2005; 288:F1133-43. [PMID: 15687248 DOI: 10.1152/ajprenal.00210.2004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The environmental pollutant cadmium affects human health, with the kidney being a primary target. In addition to proximal tubules, glomeruli and their contractile mesangial cells have also been identified as targets of cadmium nephrotoxicity. Glomerular contraction is thought to contribute to reduced glomerular filtration, a characteristic of cadmium nephrotoxicity. Because p38 MAPK/HSP25 signaling has been implicated in smooth muscle contraction, we examined its role in cadmium-induced contraction of mesangial cells. We report that exposure of mesangial cells to cadmium resulted in 1) cell contraction, 2) activation of MAP kinases, 3) increased HSP25 phosphorylation coincident with p38 MAP kinase activation, 4) sequential phosphorylation of the two phosphorylation sites of mouse HSP25 with Ser15 being phosphorylated before Ser86, 5) reduction of oligomeric size of HSP25, and 6) association of HSP25 with microfilaments. Exposure of isolated rat glomeruli to cadmium also resulted in contraction and increased HSP25 phosphorylation. The cadmium-induced responses were inhibited by the specific p38 MAP kinase inhibitor SB-203580, and cadmium-induced phosphorylation of HSP25 was inhibited by expression of a dominant-negative p38 MAP kinase mutant. These findings tentatively suggest that cadmium-induced nephrotoxicity results, in part, from glomerular contraction due to p38 MAP kinase/HSP25 signaling-dependent contraction of mesangial cells. With regard to the cellular action of HSP25, these data support a change in paradigm: in addition to its well-established cytoprotective function, HSP25 may also be involved in processes that ultimately lead to adverse effects, as is observed in the response of mesangial cells to cadmium.
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Affiliation(s)
- Sahoko Hirano
- Dept. of Cell and Developmental Biology, Univ. of Michigan Medical School, 1335 Catherine St., Ann Arbor, MI 48109-0616, USA
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Wittman R, Hu H. Cadmium exposure and nephropathy in a 28-year-old female metals worker. ENVIRONMENTAL HEALTH PERSPECTIVES 2002; 110:1261-6. [PMID: 12460807 PMCID: PMC1241115 DOI: 10.1289/ehp.021101261] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A 28-year-old female presented for evaluation of left flank pain and polyuria after having been exposed to cadmium in the jewelry manufacturing industry for approximately 3 years. This patient possessed both elevated 24-hr urinary ss2-microglobulin and elevated blood cadmium levels. Approximately 6 months after initial presentation, the patient resigned from her job due to shortness of breath, chest pain, and anxiety. Exposure to cadmium in the jewelry industry is a significant source of occupational cadmium exposure. Other occupational sources include the manufacture of nickel-cadmium batteries, metal plating, zinc and lead refining, smelting of cadmium and lead, and production of plastics. Cadmium is also an environmental pollutant that accumulates in leafy vegetables and plants, including tobacco. Major toxicities anticipated from cadmium exposure involve the renal, pulmonary, and, to a lesser extent, gastrointestinal systems. These include the development of renal proximal tubular dysfunction, glomerular damage with progressive renal disease, and respiratory symptoms including pneumonitis and emphysema. Low-level cadmium exposure has also been associated with increased urinary calcium excretion and direct bone toxicity, effects that recent research suggests may result in the development of osteoporosis. The body burden of cadmium, over half of which may reside in the kidneys, is most often measured through the use of urinary cadmium levels. Blood cadmium measurements generally reflect current or recent exposure and are especially useful in cases with a short exposure period and only minimal accumulation of cadmium in the kidneys. Both ss2-microglobulin and alpha1-microglobulin serve as organ-specific, early-effect biomarkers of tubular proteinuria and thus play a role in identifying early signs of cadmium-induced renal damage in those with potential exposures. In addition to ensuring workplace compliance with Occupational Safety and Health Administration-mandated monitoring and screening measures, it is prudent for those with cadmium exposure to maintain adequate intake of both iron and calcium, appropriate measures even in the absence of exposure.
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Affiliation(s)
- Richard Wittman
- Occupational Health Program, Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
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Noonan CW, Sarasua SM, Campagna D, Kathman SJ, Lybarger JA, Mueller PW. Effects of exposure to low levels of environmental cadmium on renal biomarkers. ENVIRONMENTAL HEALTH PERSPECTIVES 2002; 110:151-5. [PMID: 11836143 PMCID: PMC1240729 DOI: 10.1289/ehp.02110151] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We conducted a study among residents of a small community contaminated with heavy metals from a defunct zinc smelter and residents from a comparison community to determine whether biologic measures of cadmium exposure were associated with biomarkers of early kidney damage. Creatinine-adjusted urinary cadmium levels did not differ between the smelter and comparison communities; thus we combined individuals from both communities (n = 361) for further analyses. The overall mean urinary cadmium level was low, 0.26 microg/g creatinine, similar to reference values observed in the U.S. general population. For children ages 6-17 years, urinary concentration of N-acetyl-beta-D-glucosaminidase (NAG), alanine aminopeptidase (AAP), and albumin were positively associated with urinary cadmium, but these associations did not remain statistically significant after adjusting for urinary creatinine and other potential confounders. For adults ages 18 or older, urinary concentration of NAG, AAP, and albumin were positively associated with urinary cadmium. The associations with NAG and AAP but not with albumin remained statistically significant after adjusting for creatinine and other potential confounders. We found a positive dose-effect relationship between levels of creatinine-adjusted urinary cadmium and NAG and AAP activity, and statistically significant differences in mean activity for these two enzymes between the highest (> or =1.0 microg cadmium/g creatinine) and the lowest (< or =0.25 microg cadmium/g creatinine) exposure groups. The findings of this study indicate that biologic measures of cadmium exposure at levels below 2.0 microg/g creatinine may produce measurable changes in kidney biomarkers.
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Affiliation(s)
- Curtis W Noonan
- Division of Health Studies, Agency for Toxic Substances and Disease Registry, 1600 Clifton Road NE, Atlanta, GA 30333, USA.
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Pless-Mulloli T, Boettcher M, Steiner M, Berger J. alpha-1-Microglobulin: epidemiological indicator for tubular dysfunction induced by cadmium? Occup Environ Med 1998; 55:440-5. [PMID: 9816376 PMCID: PMC1757603 DOI: 10.1136/oem.55.7.440] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To evaluate the suitability of alpha-1-microglobulin as a marker for cadmium induced renal dysfunction. METHODS alpha-1-Microglobulin was studied in a cross sectional survey in relation to the body burden of cadmium. Concentrations of alpha-1-microglobulin in 24 h urine of 831 people aged 2-87 years were analysed in association with urinary cadmium excretion, cadmium blood concentration, age, sex, occupational and smoking history, and estimated creatinine clearance. Participants came from a population residentially exposed to cadmium and from two control populations matched for socioeconomic status. RESULTS The excretion of alpha-1-microglobulin/24 h ranged from 0.1 mg to 176.3 mg and 44.4% of samples showed concentrations near the detection limit. Ordinal logistic regression analysis of people of all ages identified a high risk only for males compared with females (odds ratio (OR) 2.14; 95% confidence interval (95% CI) 1.56 to 2.94), age group, and duration of living on contaminated soil (OR 1.03/year; 95% CI 1.02 to 1.04), but not urinary cadmium excretion (OR 1.30; 95% CI 0.96 to 1.77) as significant predictors. For people < or = 50 years of age a weaker effect of sex (OR 1.76; 95% CI 1.13 to 2.73) and age group and an effect of similar magnitude for the duration of soil exposure (OR 1.03; 95% CI 1.01 to 1.04) were found. Also, the urinary cadmium excretion (OR 2.26; 95% CI 1.38 to 3.70) and occupational exposure (OR 1.71; 95% CI 1.03 to 2.83) were found to be significant in this younger age group. The estimated creatinine clearance had no significant impact on the alpha-1-microglobulin excretion. CONCLUSION alpha-1-Microglobulin is a suitable marker for early tubular changes only for people < or = 50 years. It may not be sufficiently specific for cadmium, and therefore not a suitable surrogate for cadmium exposure in epidemiological studies.
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Affiliation(s)
- T Pless-Mulloli
- Department of Epidemiology and Public Health, School of Health Sciences, University of Newcastle upon Tyne, UK
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Chalkley SR, Richmond J, Barltrop D. Measurement of vitamin D3 metabolites in smelter workers exposed to lead and cadmium. Occup Environ Med 1998; 55:446-52. [PMID: 9816377 PMCID: PMC1757616 DOI: 10.1136/oem.55.7.446] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVES To investigate the effects of lead and cadmium on the metabolic pathway of vitamin D3. METHODS Blood and urinary cadmium and urinary total proteins were measured in 59 smelter workers occupationally exposed to lead and cadmium. In 19 of these workers, the plasma vitamin D3 metabolites, (25-hydroxycholecalciferol (25 OHD3), 24R, 25-dihydroxycholecalciferol (24R,25(OH)2D3) and 1 alpha,25-dihydroxycholecalciferol (1 alpha, 25(OH)2D3)) were measured together with blood lead. Vitamin D3 metabolites were measured by radioimmunoassay, (RIA), lead and cadmium by atomic absorption spectrophotometry, and total proteins with a test kit. RESULTS Ranges for plasma 25(OH)D3, 24R,25(OH)2D3 and 1 alpha,25(OH)2D3 were 1.0-51.9 ng/ml, 0.6-5.8 ng/ml, and 0.1-75.7 pg/ml, respectively. Ranges for blood lead were 1-3.7 mumol/l, (21-76 micrograms/dl), blood cadmium 6-145 nmol/l, and urinary cadmium 3-161 nmol/l. Total proteins in random urine samples were 2.1-32.6 mg/dl. Concentrations of lead and cadmium in blood showed no correlation (correlation coefficient -0.265) but there was a highly significant correlation between blood and urinary cadmium. Concentrations for 24R,25(OH)2D3 were depressed below the normal range as blood and urinary cadmium increased, irrespective of lead concentrations. High cadmium concentrations were associated with decreased plasma 1 alpha,25(OH)2D3 when lead concentrations were < 1.9 mumol/l and with above normal plasma 1 alpha,25(OH)2D3 when lead concentrations were > 1.9 mumol/l, Kruskal-Wallis analysis of variance (K-W ANOVA) chi 2 = 10.3, p = 0.006. Plasma 25(OH)D3 was negatively correlated with both urinary total proteins and urinary cadmium, but showed no correlation with plasma 24R,25(OH)2D3, 1 alpha,25(OH)2D3, blood lead, or blood cadmium. CONCLUSION Continuous long term exposure to cadmium may result in a state of equilibrium between blood and urinary cadmium. Cadmium concentrations in blood could be predicted from the cadmium concentration of the urine, (regression coefficient +0.35 SE 0.077). Exposure to cadmium alone decreased the concentrations of 1 alpha,25(OH)2D3 and 24R,25(OH)2D3, whereas exposure to both cadmium and lead increased the concentrations of 1 alpha,25(OH)2D3. It has been suggested that cadmium and lead interact with renal mitochondrial hydroxylases of the vitamin D3 endocrine complex. Perturbation of the vitamin D metabolic pathway by cadmium may result in health effect, such as osteoporosis or osteomalacia, risks which are possibly increased in the presence of lead.
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Affiliation(s)
- S R Chalkley
- Department of Academic Child Health, Imperial College School of Medicine, Chelsea
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Mueller PW, Price RG, Finn WF. New approaches for detecting thresholds of human nephrotoxicity using cadmium as an example. ENVIRONMENTAL HEALTH PERSPECTIVES 1998; 106:227-30. [PMID: 9647892 PMCID: PMC1533091 DOI: 10.1289/ehp.98106227] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Damage to the kidneys is one of the primary toxic actions of metals. Nephrotoxic substances not only cause renal disease directly, but they can also destroy renal reserve capacity, potentially placing those people with additional risk factors, such as diabetes, hypertension, cardiovascular disease, and genetic predispositions, at greater risk. To detect nephrotoxicity in people at a stage where intervention can be effective, sensitive methods are needed. One of the major advantages of using sensitive biomarkers of renal damage is that people who may be particularly susceptible to renal damage can be identified early, at a reversible stage of damage, and the progression to end-stage renal disease may be halted or delayed. Various categories of tests can be used to detect effects of nephrotoxic substances on the kidney. Through the use of biomarkers of damage to various parts of the nephron, U.S. and European studies have both shown a similar pattern of damage among men occupationally exposed to cadmium. These studies indicate various thresholds of renal effects, which researchers suggest represent a cascade of progressively severe damage to the kidney. Research into new biomarkers of damage caused by exposure to nephrotoxic substances centers around mechanisms of cell death, including necrosis and apoptosis; mechanisms of cell growth, regeneration, and proliferation, including factors that control cell cycle, influence gene expression, and modulate nucleic acid synthesis; and genetic factors that increase susceptibility to renal disease. Examples of types of candidate biomarkers include cytokines, lipid mediators, growth factors, transcription factors and protooncogenes, extracellular matrix components (collagen, glycoproteins, and proteoglycans), and cell adhesion molecules. Research into new categories of biomarkers may provide additional insights into the mechanisms of damage caused by nephrotoxins.
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Affiliation(s)
- P W Mueller
- Center for Disease Control and Prevention, Atlanta, GA 30341, USA
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17
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Affiliation(s)
- P Hoet
- Université catholique de Louvain, Faculté de médecine, Ecole de santé publique, Unité de toxicologie industrielle et médecine du travail, Bruxelles, Belgique
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Nortier J, Bernard A, Roels H, Deschodt-Lanckman M, Gueuning C, Lauwerys R. Urinary neutral endopeptidase in workers exposed to cadmium: interaction with cigarette smoking. Occup Environ Med 1997; 54:432-6. [PMID: 9245950 PMCID: PMC1128804 DOI: 10.1136/oem.54.6.432] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVES Structural impairment of the renal proximal tubular epithelium induced by cadmium (Cd) was investigated by measuring the concentration of neutral endopeptidase 24.11 (NEP), an ectoenzyme of the apical brush border, in the urine of 106 male workers employed in a Cd smelter (among whom 52 were occupationally exposed to Cd), and by comparing it with other tubular markers (low molecular weight proteins, lysosomal enzymes). METHODS NEP (EC 3.4.24.11), beta-N-acetyl-glucosaminidase (NAG) (EC 3.2.1.30), and NAG-B isoenzyme activities were measured by fluorimetric assays, whereas the concentrations of retinol binding protein (RBP), beta 2-microglobulin (beta 2M), and Clara cell protein (CC16) were measured by automated latex agglutination techniques. RESULTS An increased urinary excretion of NEP as well as microproteins was found only in subjects excreting more than 5 micrograms Cd/g creatinine. In this group, NEP concentrations were significantly higher in the subjects who smoked. This significant interaction could not be found for any other marker tested. CONCLUSIONS The data suggest that NEP enzymuria is high even at low exposures to Cd (with a threshold of urinary cadmium excretion (U-Cd) at 5 micrograms/g creatinine), indicating early structural alterations. Moreover, its particular sensitivity to smoking could be useful in the detection of new population clusters potentially more susceptible to development of nephrotoxic insult.
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Affiliation(s)
- J Nortier
- Laboratoire Pluridisciplinaire de Recherche Expérimentale Biomédicale, Université Libre de Bruxelles
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19
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Cole DC, Kearney JP. Blood cadmium, game consumption and tobacco smoking in southern Ontario anglers and hunters. Canadian Journal of Public Health 1997. [PMID: 9094805 DOI: 10.1007/bf03403858] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- D C Cole
- Environmental Health Program, McMaster University, Hamilton, ON
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Watanabe T, Nakatsuka H, Shimbo S, Iwami O, Imai Y, Moon CS, Zhang ZW, Iguchi H, Ikeda M. Reduced cadmium and lead burden in Japan in the past 10 years. Int Arch Occup Environ Health 1996; 68:305-14. [PMID: 8832295 DOI: 10.1007/bf00409415] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To investigate the current levels of exposure of the Japanese population to cadmium and lead, in comparison with the levels in 1980s. DESIGN A nation wide survey was conducted in 1991-1994 (the 1990 study) in 19 study sites in Japan as a follow-up to a study conducted in 1979-1983 (the 1980 study). Blood samples and 24-h total food duplicates were collected from women who did not smoke or drink habitually. METHODS Blood and food duplicates (after homogenization) were analysed for cadmium (Cd-B and Cd-F, respectively) and lead (Pb-B and Pb-F) by graphite furnace atomic absorption after wet-ashing. RESULTS Altogether, 467 women volunteered for blood sampling. Of these women, 375 also gave food duplicates. Geometric mean (GM) Cd-B levels in the 1990 study were lower than the corresponding 1980 values in most study sites so that the 1990 grand GM (1.98 ng/ml) for Cd-B was significantly lower than the 1980 GM (3.58 ng/ml). This reduction in Cd-B was related to the reduction in Cd-F (GM for Cd-F was 38.0 micrograms/day in the 1980 study and 30.0 micrograms/day in the 1990 study). Dietary intake was almost exclusively the route of Cd burden among the populations studied. Both Pb-B and Pb-F also showed a remarkable reduction, i.e. from 33.9 ng/ml (1980 GM) to 23.2 ng/ml (1990 GM) in the case of Pb-B, and from 32.2 micrograms/day (1980 GM) to 7.1 micrograms/day (1990 GM) in the case of Pb-F. Pb-B, however, did not correlate with Pb-F either in the 1980 or the 1990 study, because Pb intake via inhalation of air remained significant when compared with dietary intake. CONCLUSION The Cd burden in Japan has decreased markedly in the past 10 years, although it is still higher than in other countries. The Pb burden has been quite low.
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Affiliation(s)
- T Watanabe
- Department of Public Health, Kyoto University Faculty of Medicine, Japan
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Ikeda M, Zhang ZW, Moon CS, Imai Y, Watanabe T, Shimbo S, Ma WC, Lee CC, Guo YL. Background exposure of general population to cadmium and lead in Tainan city, Taiwan. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1996; 30:121-126. [PMID: 8579381 DOI: 10.1007/bf00211337] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Venous blood samples, 24-h total food duplicate samples, and rice samples were collected from 52 adult non-smoking women in the city of Tainan, southern Taiwan, in 1994, and analyzed for cadmium (Cd) and lead (Pb) by wet-digestion followed by graphite furnace atomic absorption spectrophotometry. Daily dietary intake was 10 micrograms for Cd and 22 micrograms for Pb as geometric means, of which Cd and Pb in rice accounted for 34% and 1.4% of daily Cd and Pb intakes, respectively. The counterpart values for blood were 1.11 ng/ml and 44.5 ng/ml for Cd and Pb, respectively. International comparison with recently published data suggests that the exposure to Cd in Tainan should be among the lowest in the world.
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Affiliation(s)
- M Ikeda
- Department of Public Health, Kyoto University Faculty of Medicine, Japan
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Bernard A, Thielemans N, Roels H, Lauwerys R. Association between NAG-B and cadmium in urine with no evidence of a threshold. Occup Environ Med 1995; 52:177-80. [PMID: 7735390 PMCID: PMC1128183 DOI: 10.1136/oem.52.3.177] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVES To explore the significance of the increase in urinary excretion of the lysosomal enzyme beta-N-acetylglucosaminidase (NAG) at low exposures to cadmium (Cd) that is frequently found in the absence of any other sign of renal dysfunction. METHODS The activity was measured of the two main isoenzymes of NAG (NAG-A secreted by exocytosis and NAG-B released with cell membranes) in the urine of 49 male workers employed in a Cd smelter and of 20 age matched controls. RESULTS An increased urinary excretion of low molecular weight proteins was noted only in subjects who excreted > 10 micrograms Cd/g creatinine. The urinary activity of NAG-B showed a dose related increase that was already significant in the group excreting 0.5-2 micrograms Cd/g creatinine. In multiple regression analysis the NAG-B activity correlated with the excretion of Cd but not with that of lead or mercury. The NAG-A activity was by contrast unaffected by exposure to Cd but correlated with the urinary excretion of lead and copper. CONCLUSIONS As NAG-B is considered to be the lesional form of NAG, the existence of a specific association between this enzyme and urinary Cd excretion with no detectable threshold suggests that this metal produces cellular alterations at exposures commonly found in the general population.
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Affiliation(s)
- A Bernard
- Unit of Industrial Toxicology and Occupational Medicine, Catholic University of Louvain, Faculty of Medicine, Brussels, Belgium
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Cárdenas A, Roels H, Bernard AM, Barbon R, Buchet JP, Lauwerys RR, Roselló J, Ramis I, Mutti A, Franchini I. Markers of early renal changes induced by industrial pollutants. II. Application to workers exposed to lead. BRITISH JOURNAL OF INDUSTRIAL MEDICINE 1993; 50:28-36. [PMID: 8431388 PMCID: PMC1061231 DOI: 10.1136/oem.50.1.28] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The present study has been carried out in the framework of a collaborative research project on the development of new markers of nephrotoxicity. A battery of more than 20 potential indicators of renal changes has been applied to 50 workers exposed to lead (Pb) and 50 control subjects. After application of selection criteria 41 exposed and 41 control workers were eventually retained for the final statistical analysis. The average blood Pb concentration of exposed workers was 480 micrograms/l and their mean duration of exposure was 14 years. The battery of tests included parameters capable of detecting functional deficits (for example, urinary proteins of low or high molecular weight), biochemical alterations (for example, urinary eicosanoids, glycosaminoglycans, sialic acid) or cell damage (for example, urinary tubular antigens or enzymes) at different sites of the nephron or the kidney. The most outstanding effect found in workers exposed to Pb was an interference with the renal synthesis of eicosanoids, resulting in lower urinary excretion of 6-keto-PGF1 alpha and an enhanced excretion of thromboxane (TXB2). The health significance of these biochemical alterations, detectable at low exposure to Pb is unknown. As they were not associated with any sign of renal dysfunction, they may represent reversible biochemical effects or only contribute to the degradation of the renal function from the onset of clinical Pb nephropathy. The urinary excretion of some tubular antigens was also positively associated with duration of exposure to Pb. Another effect of Pb that might deserve further study is a significant increase in urinary sialic acid concentration.
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Affiliation(s)
- A Cárdenas
- Unité de Toxicologie Industrielle et Médecine du Travail, Faculté de Médecine, Université Catholique de Louvain
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