26
|
Haufroid V, Thirion F, Mertens P, Buchet JP, Lison D. Biological monitoring of workers exposed to low levels of 2-butoxyethanol. Int Arch Occup Environ Health 1997; 70:232-6. [PMID: 9342622 DOI: 10.1007/s004200050212] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVES (1) To assess the value of urinary butoxyacetic acid (BAA) measurement for the monitoring of workers exposed to low concentration of 2-butoxyethanol (BE); (2) to evaluate the in vivo effect of low occupational BE exposure on the erythrocyte lineage; and (3) to test the possible influence of genetic polymorphism for cytochrome P450 2E1 (CYP 2E1) on urinary BAA excretion rate. METHODS Thirty-one male workers exposed to BE in a beverage package production plant were examined according to their external (BE) and internal (BAA) solvent exposure. The effect of this exposure on erythrocyte lineage [red blood cell numeration (RBC), hemoglobin (Hb), hematocrit (Htc), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), haptoglobin (Hp), reticulocyte numeration (Ret) and osmotic resistance (OR)], hepatic [aspartate aminotransferase (GOT), alanine aminotransferase (GPT)] and renal [plasmatic creatinine, urinary retinol binding protein (RBP)] parameters was also investigated. DNA purified from whole blood was used for CYP 2E1 genotyping. RESULTS Average airborne concentration of BE was 2.91 mg/m3 (0.59 ppm) with a standard deviation of 1.30 mg/m3 (0.27 ppm). There was a relatively good correlation between external and internal exposure estimated by measuring BAA in post-shift urine samples (average 10.4 mg/g creatinine; r = 0.55; P = 0.0012). Compared with a matched control group (n = 21) exposed workers had a statistically significant decrease (3.3%; P = 0.03) in Hct while MCHC was increased (2.1%; P = 0.02). No significant difference was observed either in other erythroid parameters or in hepatic and renal biomarkers. One exposed individual exhibited a mutant allele with increased cytochrome P450 oxidative activity which coincided with a very low urinary BAA excretion. CONCLUSIONS Single determination of BAA in post-shift urine samples can be used to assess exposure to low levels of BE. A slight but significant effect on erythroid parameters suggesting membrane damage was observed in exposed workers. The influence of the genetic polymorphism for CYP 2E1 deserves further investigation for the interpretation of urinary BAA measurements.
Collapse
|
27
|
Broeckaert F, Buchet JP, Huaux F, Lardot C, Lison D, Yager JW. Reduction of the ex vivo production of tumor necrosis factor alpha by alveolar phagocytes after administration of coal fly ash and copper smelter dust. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1997; 51:189-202. [PMID: 9176558 DOI: 10.1080/00984109708984021] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We investigated the effect of intratracheally instilled coal fly ash (FA) and copper smelter dust (CU) on the lung integrity and on the ex vivo release of tumor necrosis factor alpha (TNF-alpha) by alveolar phagocytes. Groups of female NMRI mice received a single intratracheal administration of different particles normalized for the arsenic content (20 micrograms/kg body weight, i.e., 600 ng arsenic/mouse) and the particle load (100 mg/kg body weight, i.e., 3 mg/mouse). Mice received tungsten carbide (WC) alone (100 mg/kg), FA alone (100 mg/kg, i.e., 20 micrograms arsenic/kg), CU mixed with WC (CU, 13.6 mg/kg, i.e., 20 micrograms arsenic/kg; WC, 86.4 mg/kg) and Ca3(AsO4)2 mixed with WC (20 micrograms arsenic/kg; WC, 100 mg/kg). Animals were sacrificed at 1, 6, or 30 d posttreatment and analyzed by bronchoalveolar lavage for total protein (TP) content, inflammatory cell number and type, and TNF-alpha production. Additional mice were studied to evaluate particle retention by measuring total arsenic retention in the lung at appropriate times. Instillation of WC induced a mild and transient (d 1) inflammatory reaction characterized by an increase of TP and an influx of polymorphonuclear leukocytes in the alveolar compartment. Compared to WC, Ca3(AsO4)2 produced a significant increase of TP content in BALF. CU particles caused a severe but transient inflammatory reaction, while a persisting alveolitis (30 d) was observed after treatment with FA. Compared to control saline, a marked inhibition of TNF-alpha release was observed in response to LPS in all groups at d 1. Cytokine production was upregulated in WC- and Ca3(AsO4)1-treated animals after 6 and 30 d, respectively. However, a 90% inhibition of TNF-alpha production was still observed at d 30 after administration of CU and FA. Although arsenic was cleared from the lung tissue 6 d after Ca3(AsO4)2 administration, a significant fraction persisted (10-15% of the arsenic administered) in the lung of CU- and FA-treated mice at d 30. We hypothetize that suppression of TNF-alpha production is dependent upon the slow elimination of the particles and their metal content from the lung.
Collapse
|
28
|
|
29
|
Hotz P, Carbonnelle P, Haufroid V, Tschopp A, Buchet JP, Lauwerys R. Biological monitoring of vehicle mechanics and other workers exposed to low concentrations of benzene. Int Arch Occup Environ Health 1997; 70:29-40. [PMID: 9258705 DOI: 10.1007/s004200050183] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
It has been suggested that the threshold limit value (TLV) for the time-weighted average (TWA), of benzene be lowered because of its possible leukemogenic effect at low exposure concentrations. This requires the development of new methods of biological monitoring. In this cross-sectional study the diagnostic power of blood and breath benzene and of urinary phenol, catechol, hydroquinone, S-phenylmercapturic acid, and muconic acid were compared in a population of 410 male workers exposed to benzene in garages, in two coke plants, and in a by-product plant. Benzene exposure was assessed by personal air sampling (charcoal tube and passive dosimeter). In all, 95% of the workers were exposed to less than 0.5 ppm benzene. According to the multiple regression equation, the muconic acid and S-phenylmercapturic acid concentrations detected in nonsmokers exposed to 0.5 ppm benzene were 0.3 mg/g and 6 micrograms/g, respectively (range 0.2-0.6 mg/g and 1.2-8.5 micrograms/g, respectively). With muconic acid very few false-positive test results were found, and this determination remained reliable even around a cutoff level of 0.1 ppm benzene. Moreover, the diagnostic power of this test proved to be good even when diluted or concentrated urine samples were not excluded. S-Phenylmercapturic acid (S-PMA) also performed fairly well. Blood and breath benzene as well as urinary phenol (PH) and hydroquinone (HQ) were clearly less suitable biomarkers than muconic acid (MA). Catechol (CA) was not associated with occupational benzene exposure. According to the results of biological monitoring, the skin resorption of benzene from gasoline or other fuels seems negligible. Correlation, multiple regression, and likelihood ratios consistently showed that MA and S-PMA concentrations were fairly good indicators of benzene exposure in the 0.1- to 1-ppm range, even in a population comprising both smokers and nonsmokers. PH, HQ, CA, and blood and breath benzene were less suitable, if at all, in the same exposure range.
Collapse
|
30
|
Roels H, Meiers G, Delos M, Ortega I, Lauwerys R, Buchet JP, Lison D. Influence of the route of administration and the chemical form (MnCl2, MnO2) on the absorption and cerebral distribution of manganese in rats. Arch Toxicol 1997; 71:223-30. [PMID: 9101038 DOI: 10.1007/s002040050380] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The absorption and cerebral distribution of manganese (Mn) have been studied with respect to the route of administration and the chemical form of the Mn compound. Different groups of adult male rats received either MnCl2, 4H2O or MnO2 once a week for 4 weeks at a dose of 24.3 mg Mn/kg body wt. (b.w.) by oral gavage (g.) or 1.22 mg Mn/kg b.w. by intraperitoneal injection (i.p.) or intratracheal instillation (i.t.). Control rats were treated with 0.9% saline. Four days after the last administration the rats were killed and the concentration of Mn measured in blood, hepatic and cerebral tissues (cortex, cerebellum, and striatum). The liver Mn concentration was not affected by the treatments whatever the chemical form or the route of administration of the Mn compound. Administration of MnCl2 by g., i.p., and i.t. routes produced equivalent steady-state blood Mn concentrations (about 1000 ng Mn/100 ml), representing increases of 68, 59, and 68% compared with controls, respectively. Mn concentrations were significantly increased in the cortex but to a lesser extent (g., 22%; i.p., 36%; i.t., 48%) and were higher in the cerebellum after i.p. and i.t. administrations than after oral gavage. Rats treated i.t. with MnCl2 showed an elective increase of the striatal Mn concentration (205%). In contrast, MnO2 given orally did not significantly increase blood and cerebral tissue Mn concentrations; the low bioavailability is most likely due to the lack of intestinal resorption. Administration of MnO2 i.p. and i.t., however, led to significant increases of Mn concentrations in blood and cerebral tissues. These increments were not significantly different from those measured after MnCl2 administration, except for striatal Mn after i.t. which was markedly less (48%) after MnO2 administration. A comparison of the blood Mn kinetics immediately after g. and i.t. treatment with MnCl2 or MnO2 indicated that the higher elevation of blood Mn concentration (> 2000 ng Mn/100 ml) after i.t. administration of MnCl2 could account for the elective uptake of Mn in the striatum observed in repeated dosing experiments. It is concluded that the modulation of Mn distribution in brain regions according to the route of administration and the chemical form of the Mn compound may be explained on the basis of different blood Mn kinetics and regional anatomic specificities of the striatal region.
Collapse
|
31
|
Buchet JP, Lison D, Ruggeri M, Foa V, Elia G. Assessment of exposure to inorganic arsenic, a human carcinogen, due to the consumption of seafood. Arch Toxicol 1996; 70:773-8. [PMID: 8896724 DOI: 10.1007/s002040050339] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
To assess whether regular consumption of seafood, particularly fish and shellfish, by humans may lead to an overexposure to inorganic arsenic, a well-established human carcinogen, the urinary excretion of the relevant As metabolites (Asi, inorganic form; MMA, monomethylarsonic acid; DMA, dimethylarsinic acid) was compared in groups of subjects with different seafood consumption habits and in volunteers after ingestion of a known amount of seafood arsenicals. Studies of Italian cohorts, involving five groups of +/-30 subjects with different seafood consumption habits, and balance studies in Belgian volunteers failed to show a biologically significant absorption of inorganic arsenic either present as such in the food or formed from organoarsenicals during cooking or digestion. The results suggest that the digestion of some seafood, especially mussels, may increase the urinary excretion of the dimethylated arsenic metabolite. Therefore, the biological monitoring of exposure to inorganic arsenic in an industrial context should mainly rely upon specific measurement of the unmetabolized form when recent ingestion of seafood cannot be excluded.
Collapse
|
32
|
Brenard R, Laterre PF, Reynaert M, Hantson P, Mahieu P, Buchet JP, Geubel A, Rahier J. Increased hepatocytic mitotic activity as a diagnostic marker of acute arsenic intoxication. A report of two cases. J Hepatol 1996; 25:218-20. [PMID: 8878785 DOI: 10.1016/s0168-8278(96)80077-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We report two patients in whom acute arsenic poisoning was associated with a very peculiar increase in hepatocytic mitotic activity. The recognition of such an unusual picture which is likely to be related to the mitogenic properties of arsenic may be of help in the identification of acute arsenic intoxication, a life-threatening condition which is difficult to diagnose.
Collapse
|
33
|
Buchet JP, Staessen J, Roels H, Lauwerys R, Fagard R. Geographical and temporal differences in the urinary excretion of inorganic arsenic: a Belgian population study. Occup Environ Med 1996; 53:320-7. [PMID: 8673179 PMCID: PMC1128474 DOI: 10.1136/oem.53.5.320] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
OBJECTIVE This Belgian study assessed the geographical and temporal differences in the exposure of the population to inorganic arsenic, a known carcinogen. METHODS In the CadmiBel study (1985-9) the 24 h urinary arsenic excretion was measured, as an index of recent exposure, in industrialised cities (Liège: n = 664, Charleroi: n = 291), in a rural control area (Hechtel-Eksel: n = 397), and in rural districts in which the population had possibly been exposed through the drinking water or the emissions of nonferrous smelters (Wezel: n = 93, Lommel: n = 111, and Pelt: n = 133). In the PheeCad study, in 1991-5, the rural areas (n = 609) were re-examined together with an urban control area (Leuven: n = 152). RESULTS The CadmiBel results showed that after adjustment for sex, age, and body mass index, the 24 h arsenic excretion was on average low in Liège (91 nmol), Charleroi (155 nmol), Hechtel-Eksel (144 nmol), and Wezel (158 nmol), whereas the highest excretions were found in Lommel (570 nmol) and Pelt (373 nmol). During the PheeCad study, the mean 24 h arsenic excretion in the rural areas ranged from 81 to 111 nmol. This was lower than six years earlier and similar to the excretion in the control town (108 nmol). Longitudinal studies in 529 people living in the rural areas confirmed that their 24 h arsenic excretion had decreased (P < 0.001) from 222 to 100 nmol. As well as the drinking water, industry was likely to be a source of the increased exposure in Lommel and Pelt in 1985-9, because at that time the urinary arsenic excretion did not follow the regional differences in the arsenic content of the drinking water, because the fall in the arsenic excretion over time coincided with the implementation by industry of stricter environmental regulations, because in individual subjects the urinary arsenic excretion was inversely correlated with the distance to the nearest smelter, and because an increased arsenic excretion was only found downwind from the main smelter. The official network that monitors the arsenic concentration in airborne and fall out dust did not detect the high exposure in Lommel and Pelt between 1985 and 1989. CONCLUSION This study highlights the necessity to validate environmental monitoring programmes by directly estimating the internal exposure of the population.
Collapse
|
34
|
Carbonnelle P, Boukortt S, Lison D, Buchet JP. Determination of toluenediamines in urine of workers occupationally exposed to isocyanates by high-performance liquid chromatography. Analyst 1996; 121:663-9. [PMID: 8779450 DOI: 10.1039/an9962100663] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In recent years, epidemiological evidence that exposure to toluene diisocyanate (TDI) is associated with adverse health effects has led to the development of useful analytical methods for the biological monitoring of TDI. In this paper, an HPLC method is presented that allows accurate determinations of toluenediamines (TDA), urinary metabolites of TDI, in hydrolysed human urine without complicated or time-consuming sample treatment. The procedure requires 5.0 ml of urine and involves the extraction with toluene of TDA and the hydrolysable conjugate fraction followed by further purification with a strong cation-exchange sorbent. Strongly alkaline conditions are chosen for the hydrolysis of urine samples and phenylene-1,3-diamine is used as internal standard to control the sample extraction and clean-up. Separation is performed on a base-deactivated octadecyl reversed-phase column by either ion-suppression or ion-pair chromatography. Chromatographic analysis is complete in less than 20 min and chromatograms with no interfering peaks are obtained. High sensitivity and selectivity are achieved by using electrochemical detection: 2,6- and 2,4-TDA can be detected at the 0.1 and 0.15 microgram l-1 levels, respectively. Absolute recoveries of the method tested with urine samples spiked at 10 micrograms l-1 with phenylene-1,3-diamine and from 1 to 25 micrograms l-1 with 2,6-and 2,4-TDA are greater than 87.6% and 88.3%, respectively. The assay is linear from 0 to 50 micrograms l-1. Within-run precisions evaluated on 10 urine samples ranging from 0 to 10 micrograms l-1 are 7.9% and 5.3% for 2,6- and 2,4-TDA, respectively. Results obtained with urine samples from 12 controls and 15 exposed workers from a flexible polyurethane foam factory indicate that the method is appropriate for the biological monitoring of occupational exposure to TDI.
Collapse
|
35
|
Lardot C, Broeckaert F, Lison D, Buchet JP, Lauwerys R. Exogenous catalase may potentiate oxidant-mediated lung injury in the female Sprague-Dawley rat. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1996; 47:509-22. [PMID: 8614020 DOI: 10.1080/009841096161500] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Enhancement of lung antioxidant capacity has been proposed in the therapy of acute lung injuries involving local accumulation of reactive oxygen species (ROS). We have studied in the female Sprague-Dawley rat the effect of intratracheal administration of catalase (CAT) on the acute lung response induced by different ROS generating systems. The lung response was assessed at several time intervals (60-360 min) by monitoring in bronchoalveolar fluid (BALF) the activity of lactate dehydrogenase and the levels of total protein, albumin, and glucose. While CAT (50,000 IU/rat) significantly reduced the biochemical changes induced by hydrogen peroxide produced by a glucose/glucose oxidase system, it markedly exacerbated the lesions induced by phorbol myristate acetate (PMA). Several observations indicate that a particular chemical species formed during the catalase inactivation process is responsible for this effect. Parallel to the development of the lung damage, we noted a rapid reduction of CAT activity (80%) in the BALF of animals treated with PMA and CAT. In vitro an inhibition of CAT activity was observed in the presence of a superoxide anion generating system, and this inhibition was prevented by superoxide dismutase (SOD). A dose of 10,000 IU superoxide dismutase did not prevent the development of the lung lesions induced by PMA plus CAT. Administered alone or in association with PMA, CAT inactivated by heat or 3-aminotriazole also caused severe lung damage. In conclusion, the present study indicates that exogenous catalase may not always protect against the inflammatory reaction resulting from an oxidative stress. In the presence of superoxide anions, catalase may aggravate the lesions, and this possibility should be kept in mind when considering an antioxidant therapy.
Collapse
|
36
|
Staessen JA, Buchet JP, Ginucchio G, Lauwerys RR, Lijnen P, Roels H, Fagard R. Public health implications of environmental exposure to cadmium and lead: an overview of epidemiological studies in Belgium. Working Groups. JOURNAL OF CARDIOVASCULAR RISK 1996; 3:26-41. [PMID: 8783028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The CadmiBel Study was a cross-sectional population study that investigated the health effects of environmental exposure to cadmium and lead. The 2327 participants constituted a random sample of the population of four Belgian districts, chosen in order to provide a wide range of environmental exposure to cadmium. After adjustment for confounding factors, such as smoking and occupational exposure, the urinary cadmium excretion, a measure of lifetime exposure, was nearly 30% higher in the polluted areas. The CadmiBel Study produced evidence inconsistent with the hypothesis that environmental exposure to cadmium and lead would lead to an increase in blood pressure and to a higher prevalence of hypertension and other cardiovascular diseases. On the other hand, the serum alkaline phosphatase activity and the urinary excretion of calcium were significantly and positively correlated with urinary cadmium in both sexes. These findings suggested that the homeostasis of calcium was gradually affected as cadmium accumulated in the body. Furthermore, several markers of renal tubular dysfunction (urinary excretion of retinol-binding-protein, N-acetyl-beta-glucosaminidase, beta 2-microglobulin and amino acids) were significantly and positively associated with urinary cadmium. Across 10 small areas of which six were polluted with cadmium, an inverse association existed between the creatinine clearance and several indexes of environmental exposure to cadmium (cadmium concentration in the soil, cadmium content of locally grown vegetables, the inhabitants' 24 h urinary cadmium excretion). In the CadmiBel Study, the creatinine clearance was also inversely correlated with the concentrations of lead and zinc protoporphyrin in the blood. Thus, environmental exposure to cadmium and lead was associated with alterations in renal function. The significance in terms of morbidity and mortality of the functional disturbances observed in the CadmiBel Study, and the possible strategies to prevent the transfer of cadmium from the environment to man are under investigation in the prospective PheeCad Study in which half of the Cadmibel participants have been enrolled (participation rate 80%).
Collapse
|
37
|
Becker DJ, Reul B, Ozcelikay AT, Buchet JP, Henquin JC, Brichard SM. Oral selenate improves glucose homeostasis and partly reverses abnormal expression of liver glycolytic and gluconeogenic enzymes in diabetic rats. Diabetologia 1996; 39:3-11. [PMID: 8720597 DOI: 10.1007/bf00400407] [Citation(s) in RCA: 108] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Selenium is a trace element that exerts certain insulin-like actions in vitro. In this study, we evaluated its in vivo effects on the glucose homeostasis of rats made diabetic and insulin-deficient by streptozotocin. Na2SeO4 was administered ad libitum in drinking water and/or food for 10 weeks. The elevated plasma glucose levels (approximately 25 mmol/l) and glucosuria (approximately 85 mmol/day) of untreated rats were decreased by 50 and 80%, respectively, by selenate treatment. The beneficial effect of selenate was also evident during oral and intravenous glucose tolerance tests: the integrated glucose responses were decreased by 40-50% as compared to those in untreated rats. These effects were not due to an increase in plasma insulin levels. Compared to non-diabetic rats, pancreatic insulin reserves were reduced by more than 90% in treated and untreated diabetic rats. The hepatic activities and mRNA levels of two key glycolytic enzymes, glucokinase and L-type pyruvate kinase were blunted in diabetic rats. They increased approximately two- to threefold after selenate treatment, to reach 40-75% of the values in non-diabetic rats. In contrast, elevated activity and mRNA levels of the gluconeogenic enzyme, phosphoenolpyruvate carboxykinase, were reduced by 40-65% after selenate administration. Since selenate induced a moderate decrease in body weight due to an anorexigenic effect, we checked that there was no improvement of glucose homeostasis or hepatic glucose metabolism in an additional group of calorie-restricted diabetic rats, which was weight-matched with the selenate group. In addition, no obvious toxic side-effects on the kidney or liver were observed in the rats receiving selenate. In conclusion, selenate induces a sustained improvement of glucose homeostasis in streptozotocin-diabetic rats by an insulin-like action, which involves partial correction of altered pretranslational regulatory mechanisms in liver metabolism.
Collapse
|
38
|
Buchet JP, Lauwerys RR, Yager JW. Lung retention and bioavailability of arsenic after single intratracheal administration of sodium arsenite, sodium arsenate, fly ash and copper smelter dust in the hamster. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 1995; 17:182-188. [PMID: 24194290 DOI: 10.1007/bf00661330] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/1994] [Accepted: 04/10/1995] [Indexed: 06/02/2023]
Abstract
Arsenic is present in airborne particulate material released by coal-fired power plants and non-ferrous metal smelters. We have assessed whether the physico-chemical properties of arsenic in such particles play a role in its lung retention and uptake by the body. Female hamsters were given a single intratracheal instillation of fly ash or copper smelter dust suspensions (at doses of 50 or 100 μg As kg(-1)) or identical amounts of soluble tri- and pentavalent arsenic, in the presence or absence of an inert dust material (tungsten carbide). The concentration of the element was measured in a 24 hour urine sample collected on the 1st, 2nd and 6th day after treatment and arsenic remaining in lung tissue was determined at the end of the same time periods. Both lung retention and urinary As excretion indicate a prolonged contact of the lung tissue with particulate As in contrast to soluble As salts. In addition to the effect of solubility described here, more research is needed to determine the effect of particle size and lung loading on retention, as well as the potential differences in the lung inflammatory response using arsenic-rich particulates from various sources.
Collapse
|
39
|
Lauwerys RR, Bernard A, Roels H, Buchet JP. Health risk assessment of long-term exposure to non-genotoxic chemicals: application of biological indices. Toxicol Lett 1995; 77:39-44. [PMID: 7618167 DOI: 10.1016/0378-4274(95)03269-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
For chemical pollutants, health risk assessment of long-term exposure is usually best realized through an epidemiologic approach which attempts to link cumulative levels of exposure to the potential for occurrence of early adverse effects. For some chemicals, however, the frequency of peak exposures may be more relevant for assessing the health risk than the integrated dose. In very few circumstances, biological exposure indices directly reflect the cumulative dose (e.g. PCB in blood). More frequently they are indicators of short-term interval dose but provided they have been measured with a sufficient frequency, their integration over the duration of exposure may represent a valid surrogate of the cumulative dose. This has been clearly demonstrated for lead or cadmium in blood. The selection of the appropriate biological effect markers for the study of the dose-effect/dose-response relationships is frequently a controversial issue when information on the mechanism of action of the pollutant is insufficient. In this case, the study of the health significance of the observed biological changes may be required for assessing a meaningful no-adverse-effect level. For example, in adult male workers moderate exposure to lead may affect the synthesis of vasodilatory prostaglandins in the kidney but presently there is no indication that this effect should be taken into account to define the acceptable occupational exposure level to lead because it is not associated with an impairment of the hemodynamic response of the kidney to an acute protein load. On the contrary, a low-molecular-weight proteinuria induced by cadmium may be predictive of an increased age-related decline of the glomerular filtration rate. Although the use of early biological effect markers for the study of the dose-effect or dose-response relationships in humans is probably less affected by selection biases than morbidity data, the possibility of such an interference cannot be excluded. For example, in the general population, the tubulotoxic effects of cadmium may occur at a lower body burden of the metal than in adult male workers. Whatever the adverse biological effect considered, the application of an uncertainty factor remains justified when extrapolating a no-effect level from adult male workers to the general population.
Collapse
|
40
|
Buchet JP, Ferreira M, Burrion JB, Leroy T, Kirsch-Volders M, Van Hummelen P, Jacques J, Cupers L, Delavignette JP, Lauwerys R. Tumor markers in serum, polyamines and modified nucleosides in urine, and cytogenetic aberrations in lymphocytes of workers exposed to polycyclic aromatic hydrocarbons. Am J Ind Med 1995; 27:523-43. [PMID: 7793423 DOI: 10.1002/ajim.4700270406] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Some polycyclic aromatic hydrocarbons (PAHs) such as benzo(a)pyrene and benzo(a)anthracene are well-established genotoxic agents. Long-term exposure to PAHs may lead to proliferative cell disorders in humans, predominantly in the skin, lung, and bladder. The concentration of several tumor markers in serum, of polyamines and modified nucleosides in urine, and of cytogenetic endpoints in peripheral lymphocytes (sister-chromatid exchanges, high frequency cells [HFC], and micronuclei) were measured in 149 male workers exposed to PAHs in two coke oven and one graphite electrode plants, and in 137 controls. We have assessed whether these biomarkers were related to several parameters reflecting exposure to PAHs, i.e., the sum of the airborne concentration of 13 PAHs, 1-hydroxypyrene (1-OHP) concentration in postshift urine, benzo(a)pyrene-diolepoxide adducts to hemoglobin (BPDE-Hb adducts), and duration of exposure, taking also into account several possible confounding factors. HFC was the biomarker most consistently associated with the intensity of current exposure to PAHs. Smoking exerts an independent effect on the same parameter. On the basis of the logistic regression between the prevalence of abnormal HFC values and PAHs in air and 1-OHP in postshift urine found in nonsmokers, it is suggested that the latter should be kept below 6.4 micrograms/m3 and 2.7 micrograms/g creatinine, respectively. No relationship was found between the cytogenetic effects and BPDE-Hb adducts although both parameters are statistically correlated with the airborne PAH level. Some tumor markers in serum (carcinoembryonic antigen, tissue polypeptide antigen, sialic acid) and the urinary concentration of some polyamines were correlated with either PAHs in air or 1-OHP in urine. The associations, however, were very weak which suggests that these biomarkers have limited practical value for the health surveillance of groups of workers exposed to genotoxic PAHs.
Collapse
|
41
|
Louwerse ES, Buchet JP, Van Dijk MA, de Jong VJ, Lauwerys RR. Urinary excretion of lead and mercury after oral administration of meso-2,3-dimercaptosuccinic acid in patients with motor neurone disease. Int Arch Occup Environ Health 1995; 67:135-8. [PMID: 7672858 DOI: 10.1007/bf00572238] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) are progressive neurodegenerative disorders involving motor neurones. The aetiology of the non-familiar forms is still unknown but it has been suggested that long-term exposure to heavy metals such as lead and mercury may play a role in the pathogenesis of these diseases. In 53 patients suffering from ALS (n = 42) and SMA (n = 9) the oral administration of dimercaptosuccinic acid (DMSA, 20 mg/kg) did not result in a greater mobilization of lead and mercury from peripheral depots than in control subjects. Although it cannot be excluded that the amount of lead or mercury excreted after DMSA administration may not be a reflection of the amount accumulated in the motor neurons, this study does not provide support for the hypothesis that heavy metals play a significant role in the occurrence of motor neurone diseases.
Collapse
|
42
|
Tas S, Buchet JP, Lauwerys R. Determinants of benzo[a]pyrene diol epoxide adducts to albumin in workers exposed to polycyclic aromatic hydrocarbons. Int Arch Occup Environ Health 1994; 66:343-8. [PMID: 7896420 DOI: 10.1007/bf00378368] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The present study was undertaken among 260 subjects [133 controls and 127 persons exposed to polycyclic aromatic hydrocarbons (PAHs) from two steel foundries and a graphite electrode producing plant in order to investigate the relationship between the benzo[a]-pyrene-diol epoxide adducts to albumin (BPDE-alb) and the intensity of exposure to PAHs. Blood samples were collected from each subject and BPDE-alb adduct determination was performed using a high-pressure liquid chromatography technique with fluorescence detection. Exposure to PAHs was assessed by measuring airborne concentration of 13 PAHs including benzo[a]pyrene (BaP) using personal air sampling and 1-hydroxypyrene excretion (1-HOP) in postshift urine. Significantly higher BPDE-alb adduct levels were observed in exposed workers compared to controls but wide interindividual variation was observed between subjects with the same level of exposure. BPDE-alb adduct level was weakly but significantly associated with the airborne concentrations of total PAHs (r = 0.35, P = 0.0001) and BaP (r = 0.30, P = 0.0001), and urinary 1-HOP excretion (r = 0.29, P = 0.0001). Alcohol and dietary habits, place of residence, and renal and hepatic status were not found to influence the concentration of BPDE-alb adducts significantly. However, for the same level of exposure to BaP, smokers had a higher probability of having an elevated BPDE-alb adduct level than non-smokers.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
|
43
|
Roels H, Lauwerys R, Konings J, Buchet JP, Bernard A, Green S, Bradley D, Morgan W, Chettle D. Renal function and hyperfiltration capacity in lead smelter workers with high bone lead. Occup Environ Med 1994; 51:505-12. [PMID: 7951773 PMCID: PMC1128028 DOI: 10.1136/oem.51.8.505] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE The study was undertaken to assess whether the changes in urinary excretion of eicosanoids (a decrease of 6-keto-PGF1 alpha and PGF2 and an increase of thromboxane) previously found in lead (Pb) exposed workers may decrease the renal haemodynamic response to an acute oral protein load. METHODS The renal haemodynamic response was estimated by determining the capacity of the kidney to increase the glomerular filtration rate (in terms of creatinine clearance) after an acute consumption of cooked red meat (400 g). A cross sectional study was carried out in 76 male Pb workers (age range 30 to 60 years) and 68 controls matched for age, sex, socioeconomic state, general environment (residence), and workshift characteristics. RESULTS The Pb workers had been exposed to lead on average for 18 (range 6-36) years and showed a threefold higher body burden of Pb than the controls as estimated by in vivo measurements of tibial Pb concentration (Pb-T) (geometric mean 66 v 21 micrograms Pb/g bone mineral). The geometric mean concentrations of Pb in blood (Pb-B) and Pb in urine (Pb-U) were also significantly higher in the Pb group (Pb-B: 430 v 141 micrograms Pb/l; Pb-U: 40 v 7.5 micrograms Pb/g creatinine). These conditions of chronic exposure to Pb did not entail any significant changes in the concentration of blood borne and urinary markers of nephrotoxicity, such as urinary low and high molecular weight plasma derived proteins (beta 2-microglobulin, retinol binding protein, albumin, transferrin), urinary activities of N-acetyl-beta-D-glucosaminidase and kallikrein, and serum concentrations of creatinine, beta 2-microglobulin, urea, and uric acid. All participants also had normal baseline creatinine clearances (> 80 ml/min/1.73 m2) amounting on average to 115.5 in the controls v 121.3 ml/min/1.73 m2 in the Pb group. Both control and Pb exposed workers showed a significant increment in creatinine clearance (on average 15%) after oral protein load suggesting that the previously found changes in secretion of urinary eicosanoids apparently has no deleterious effect on renal haemodynamics in the examined Pb workers. CONCLUSIONS The finding that both baseline and stimulated creatinine clearance rates were not only significantly higher in the Pb workers but also positively correlated with Pb-T, suggests that moderate exposure to Pb may be associated with a slight hyperfiltration state, which has been found to attenuate the age related decline in baseline creatinine clearance by a factor of two. Although the relevance of this effect for the worker's health is unknown, it can be concluded that adverse renal changes are unlikely to occur in most adult male Pb workers when their blood Pb concentration is regularly kept below 700 micrograms Pb/l. One should, however, be cautious in extra-polating this conclusion to the general population because of pre-employment screening of the Pb workers for the absence of renal risk factors.
Collapse
|
44
|
Lauwerys RR, Bernard AM, Roels HA, Buchet JP. Cadmium: exposure markers as predictors of nephrotoxic effects. Clin Chem 1994. [DOI: 10.1093/clinchem/40.7.1391] [Citation(s) in RCA: 143] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
Cadmium (Cd) is a cumulative element with a biological half-life of > 10 years in humans. The total amount of Cd accumulated in the liver and in the kidney can be measured in vivo by neutron activation (or x-ray fluorescence), but this technique does not necessarily measure the fraction that is biologically active. At low exposure (i.e., general environmental exposure or moderate occupational exposure), blood Cd is mainly influenced by the last 2 to 3 months of exposure. Under such conditions, the Cd concentration in urine mainly reflects the amount of Cd stored in the body, particularly in the kidney. In Europe and the US, the Cd reference values are usually < 2 nmol/mmol creatinine. Because most of the Cd in urine is probably bound to metallothionein, the changes in the urinary metallothionein concentration parallel those of Cd. The determination of Cd concentration in hair is of limited value because in humans it is difficult to distinguish between externally deposited and endogenous Cd. Fecal Cd is a good indicator of the oral daily intake. The results of several cross-sectional epidemiologic studies of the relation between the prevalence of renal dysfunction and Cd concentration in urine led us to propose a biological limit value for Cd of 5 and 2 nmol/mmol creatine for adult male workers and the general population, respectively.
Collapse
|
45
|
Bernard AM, Roels HA, Buchet JP, Lauwerys RR. Serum Clara cell protein: an indicator of bronchial cell dysfunction caused by tobacco smoking. ENVIRONMENTAL RESEARCH 1994; 66:96-104. [PMID: 8013441 DOI: 10.1006/enrs.1994.1047] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Clara cell protein (CC16) is a 16-kDa protein secreted by Clara cells and other nonciliated cells of both the bronchiolar and bronchial epithelium. CC16 is present in high concentrations in the respiratory tract secretions but occurs also in other fluids such as serum. In this study, CC16 has been measured in the sera from 65 female and 69 male current smokers and in a sex- and age-matched control group of 135 neversmokers. Lifetime smoking averaged (geometric mean) 12.7 (range, 0.6 to 61.3) and 17.9 (range, 0.8 to 126) pack-years in female and male smokers, respectively. A significant reduction of Clara cell protein was found in the sera of smokers of both sexes. In neversmokers serum CC16 was independent of sex but significantly increased with age. In current smokers serum CC16 was also negatively correlated with both the current and lifetime cigarette consumption and with the 24-h urinary excretion of thiocyanate. After adjustment for age, a linear dose-response relation was apparent between smoking history and serum CC16, the latter decreasing on average by about 15% for each 10 pack-year smoking history. The present study supports the concept that CC16 in serum is a marker of bronchial dysfunction caused by tobacco smoke. As CC16 appears to be a natural immunosuppressor of the respiratory tract, its decreased production might explain some inflammatory changes associated with smoking.
Collapse
|
46
|
Buchet JP, Pauwels J, Lauwerys R. Assessment of exposure to inorganic arsenic following ingestion of marine organisms by volunteers. ENVIRONMENTAL RESEARCH 1994; 66:44-51. [PMID: 8013437 DOI: 10.1006/enrs.1994.1043] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A study was undertaken to assess whether the consumption of fish and shellfish containing a high concentration (> 1500 micrograms/kg) of organoarsenical compounds was associated with the release of a significant amount of inorganic arsenic (Asi) in vivo. Volunteers were given a known quantity of seafood (ray, cod, plaice, mussel) whose content in total arsenic (As), Asi, monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) was determined. In addition to the total amount of As excreted within 48 hours, that of Asi and its methylated metabolites (MMA, DMA) was also monitored and compared with that expected on the basis of the results of our previous studies on the toxicokinetics of Asi, MMA, and DMA in humans. Ingestion of ray, cod, or plaice does not seem to be associated with a significant release of Asi in vivo. Following consumption of mussels, however, the amount of DMA excreted in urine is significantly higher than that expected on the basis of the amount of Asi and its methylated derivatives already present in the shellfish. It was also noted that among the different marine organisms analyzed (ray, cod, plaice, sole, sea-bream, mussel), the highest proportion of Asi (on the average 3% of the total) was found in mussels. Further metabolic studies are justified to assess the risk of exposure to Asi associated with the consumption of shellfish. In view of the possible release of dimethylarsenic acid from some organoarsenicals, biological monitoring of occupational exposure to Asi by the measurement of its methylated metabolites can provide misleading results if the workers have consumed some marine organisms within 48 hr before urine collection.
Collapse
|
47
|
Ferreira Júnior MF, Tas S, dell'Omo M, Goormans G, Buchet JP, Lauwerys R. Determinants of benzo(a)pyrenediol epoxide adducts to haemoglobin in workers exposed to polycyclic aromatic hydrocarbons. Occup Environ Med 1994; 51:451-5. [PMID: 8044243 PMCID: PMC1128013 DOI: 10.1136/oem.51.7.451] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE The aim was to assess the determinants of benzo(a)pyrenediol epoxide adducts to haemoglobin (BaPDE-Hb) in workers exposed to polycyclic aromatic hydrocarbons (PAHs). METHODS This was a study of the correlations between the concentrations of PAHs in air, 1-hydroxyprene in urine, and BaPDE-Hb adduct concentration in the blood in 206 men working in steel foundries and one graphite electrode producing plant, taking into consideration confounding factors such as smoking and dietary habits. RESULTS BaPDE-Hb adduct concentration was correlated (r = 0.26; p = 0.0002) with the airborne PAH concentration and was influenced by tobacco consumption but not by dietary habits. Benzo(a)-pyrene concentration in air, 1-hydroxypyrene concentration in urine, and duration of exposure to PAHs were not associated with the adduct concentration. CONCLUSION Although environmental exposure to PAHs was statistically associated with BaPDE-Hb adduct concentration, differences between individual subjects in the metabolism of benzo(a)pyrene probably play an important part in determining the amount of BaPDE-Hb adducts formed.
Collapse
|
48
|
Lison D, Buchet JP, Swennen B, Molders J, Lauwerys R. Biological monitoring of workers exposed to cobalt metal, salt, oxides, and hard metal dust. Occup Environ Med 1994; 51:447-50. [PMID: 8044242 PMCID: PMC1128012 DOI: 10.1136/oem.51.7.447] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE The aim was to examine the relation between environmental and biological (blood and urine) indices of exposure to different chemical forms of cobalt. METHODS A cross sectional study was undertaken in workers exposed to cobalt metal, oxides, and salts in a refinery and to a mixture of cobalt and tungsten carbide in a hard metal producing plant. RESULTS AND CONCLUSION Although biological monitoring of workers exposed to cobalt oxides showed higher blood and urine concentrations than in non-exposed subjects, these indices poorly reflected the recent exposure level. By contrast, when exposure was to soluble cobalt compounds (metal, salts, and hard metals), the measurement of urine or blood cobalt at the end of the workweek could be recommended for the assessment of recent exposure. An eight hour exposure to 20 or 50 micrograms/m3 of a soluble form of cobalt would lead to an average concentration in a postshift urine sample collected at the end of the workweek of 18.2 or 32.4 micrograms of cobalt/g creatinine, respectively.
Collapse
|
49
|
Lauwerys RR, Bernard AM, Roels HA, Buchet JP. Cadmium: exposure markers as predictors of nephrotoxic effects. Clin Chem 1994; 40:1391-4. [PMID: 8013125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Cadmium (Cd) is a cumulative element with a biological half-life of > 10 years in humans. The total amount of Cd accumulated in the liver and in the kidney can be measured in vivo by neutron activation (or x-ray fluorescence), but this technique does not necessarily measure the fraction that is biologically active. At low exposure (i.e., general environmental exposure or moderate occupational exposure), blood Cd is mainly influenced by the last 2 to 3 months of exposure. Under such conditions, the Cd concentration in urine mainly reflects the amount of Cd stored in the body, particularly in the kidney. In Europe and the US, the Cd reference values are usually < 2 nmol/mmol creatinine. Because most of the Cd in urine is probably bound to metallothionein, the changes in the urinary metallothionein concentration parallel those of Cd. The determination of Cd concentration in hair is of limited value because in humans it is difficult to distinguish between externally deposited and endogenous Cd. Fecal Cd is a good indicator of the oral daily intake. The results of several cross-sectional epidemiologic studies of the relation between the prevalence of renal dysfunction and Cd concentration in urine led us to propose a biological limit value for Cd of 5 and 2 nmol/mmol creatine for adult male workers and the general population, respectively.
Collapse
|
50
|
Lauwerys RR, Buchet JP, Andrien F. Muconic acid in urine: a reliable indicator of occupational exposure to benzene. Am J Ind Med 1994; 25:297-300. [PMID: 8147402 DOI: 10.1002/ajim.4700250216] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
In male subjects not occupationally exposed to benzene, the concentration of muconic acid (MA) in urine is usually below 0.5 mg/g creatinine. At ambient levels of benzene exposure (below 0.01 ppm), the mean MA level was greater in 21 smokers than in 14 nonsmokers. In 38 male subjects employed in garages and coke ovens, a statistically significant correlation was found between the airborne concentration of benzene measured with passive monitors and MA in postshift urine. The mean postshift MA concentrations corresponding to a benzene 8-hour time-weighted average exposure (TWA) of 0.5 and 1 ppm were 0.8 and 1.4 mg/g creatinine, respectively.
Collapse
|