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Biomedical subjects

R F Herber

Publications and source records attributed to R F Herber.

At least 19 recordsLinked to original sources
PubMed2000

Occupational exposure to cis-1,3-dichloropropene: biological effect monitoring of kidney and liver function.

OBJECTIVES: To investigate the possible effects of occupational exposure to the nematocide cis-1,3-dichloropropene (cis-DCP) on function of the kidney and liver in the starch potato growing region in The Netherlands. METHODS: The study involved 13 commercial application workers exposed to cis-DCP for 117 days, and 22 matched control workers. The inhalatory exposure of the application workers was estimated from biological monitoring data. All workers collected urine and serum samples before, during, and after the fumigation season for monitoring of variables for kidney and liver function. Renal effect variables were alanine aminopeptidase (AAP), N-acetyl-beta-D-glucosaminidase (NAG), retinol binding protein (RBP), and albumin (ALB) in urine, and beta(2)-microglobulin (beta(2)M-S) and creatinine in serum (Creat-S). Liver variables were alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT), gamma-glutamyltranspeptidase (GGT), alkaline phosphatase (ALP), and total bilirubin (TBIL) in serum and the urinary ratio of 6-beta-hydroxycortisol to free cortisol (betaOHC/COR). RESULTS: The geometric mean exposure of the application workers was 2.7 mg/m(3) (8 hour time weighted average (8 hour TWA)); range 0.1-9.5 mg/m(3). No differences were found between the values of the renal effect variables or the liver variables of the exposed group and the control group, except a lower urinary ratio of betaOHC/COR in the exposed group. This was not considered to be related to the exposure to cis-DCP. No dose-effect relations were found between the exposure indices and the effect variables. CONCLUSIONS: The present study does not provide evidence that occupational exposure to cis-DCP in the starch potato growing region causes adverse effects on the kidney or liver at 8 hour TWA exposure concentrations below 9.5 mg/m(3) (2 ppm).

Adult↗
PubMed1999

Occupational exposure to tetrachloroethene and its effects on the kidneys.

Occupational exposure to tetrachloroethene (TCE) has been reported to cause early adverse effects on the kidneys. We investigated the effects of TCE exposure on the kidneys in 82 exposed and 19 nonexposed workers from four dry-cleaning shops in The Netherlands. The mean inhaled amount of TCE in the exposed group, which was assessed by determination of its concentration in alveolar air samples, was 8.4 mg/m3 (range, 2.2-44.6 mg/m3). This value corresponds to a mean 8-hour time-weighted average exposure of 7.9 mg/m3 (range, 1-221 mg/m3). A chronic dose index (CDI) was estimated from data on the current TCE dose and the occupational history of the individual subjects. The mean CDI in the exposed group was 400 months X mg/m3 (range, 12-4882 months X mg/m3). Effects on the tubules were assessed with the parameters N-acetyl-beta-D-glucosaminidase, beta-galactosidase, alanine aminopeptidase, and retinol-binding protein (RBP) in urine. Early effects on the glomeruli were monitored with the parameter albumin in urine. Total protein in urine was determined for the general assessment of effects on the glomeruli and tubules. The tubular parameter RBP was increased in the exposed group, compared with the nonexposed group. None of the other parameters differed between the study groups, and none of the renal-effect parameters correlated with the TCE dose or the CDI. In conclusion, occupational exposure to TCE may cause a minor effect on the tubular RBP at exposure levels below the Dutch occupational exposure limit (240 mg/m3).

Adult↗
PubMed1998

Effects on the kidney of occupational exposure to styrene.

OBJECTIVES: To elucidate the extent of nephrotoxicity of long-term occupational exposure to styrene. METHODS: In all 10 styrene-exposed workers (employed, mean age 12.6 years) and 15 nonexposed workers were studied. Each participant collected multiple overnight and end-of-shift urine samples. The sum of the urinary concentrations of mandelic acid and phenylglyoxylic acid (MAP) was determined to assess the absorbed dose of styrene. The urinary parameters alanine aminopeptidase (AAP), beta-galactosidase (beta GAL), N-acetyl-beta-D-glucosaminidase (NAG), retinol-binding protein (RBP), and albumin (ALB) were determined to assess the effects on renal function and integrity. RESULTS: The median concentration of MAP in urine was 175 mg/g urinary creatinine (CREAT-U; range 72-496 mg/g). The 8-h time-weighted average (8-h TWA) exposure to styrene was estimated from the urinary concentration of MAP and ranged from 21 to 405 mg/m3. RBP showed a borderline correlation with the dose of styrene. ALB in end-of-shift urine samples showed a borderline correlation with the absorbed dose of styrene. CONCLUSIONS: From the borderline correlation of RBP with the dose of styrene it was concluded that there might be a slight effect on the tubuli. The borderline correlation of ALB with the dose of styrene, together with the observation that five values were above the reference limit of the laboratory, suggests an effect on this parameter.

Acute Kidney Injury↗
PubMed1997

Occupational exposure to antineoplastic agents and parameters for renal dysfunction.

To study the nephrotoxic effects of occupational exposure to antineoplastic agents, the early renal effect parameters retinol-binding protein (RBP) and albumin (ALB) were determined in the urine of 11 hospital workers involved in the preparation and administration of antineoplastic agents and in 23 hospital workers not involved in drug handling, who served as nonexposed controls. No significant difference was found between the exposed group and the nonexposed control group with respect to the early renal effect parameters RBP and ALB. Although it was demonstrated that the hospital workers were exposed to cyclophosphamide (CP) and probably other antineoplastic agents, the results of the present study show that these exposure levels did not cause nephrotoxic effects.

Adult↗
PubMed1997

Critical evaluation and review of cadmium concentrations in blood for use in occupational health according to the TRACY protocol.

Cadmium in blood (B-Cd) may be used to assess recent exposure to cadmium in the working or general environment. In a paper published elsewhere pooled reference values using meta-analysis of B-Cd values in general-population studies were calculated. In the present study tentative references intervals were described which can be used for comparison with data from occupationally exposed groups or individuals. The selection of studies was done according to criteria as published by the international project TRACY. For this purpose, 800 publications covering the period 1983-1992 were reviewed on their suitability for establishing tentative reference intervals. From these 800 publications, four finally met the selection criteria. Most important criteria for selection were the check for contamination during sampling of the blood, the storage and pretreatment procedures, and the existence of internal and external quality control programs. Also, stratifications into sex, smoking habits and occupation were important selection criteria. It turned out that for non-smoking white-collar workers in the age range of 19-65 years, B-Cd values were below 0.8 micrograms/l for most areas. All other groups within this age group, e.g., white collar workers in Japan, blue-collar workers, and smokers tend to have higher B-Cd values in these sequences. Blue-collar workers not clearly exposed to Cd have higher values than white-collar workers, indicating still some minor exposure. It is not clear if this small exposure has an occupational or lifestyle (e.g., diet) origin. Geographical regions also show an influence on B-Cd levels, e.g., values in Japan are higher than elsewhere. This influence may be due to differences in diet. The conclusion will be that reference values for B-Cd in fact are area-dependent.

Adult↗
PubMed1996

Sample collection guidelines for trace elements in blood and urine. IUPAC Commission of Toxicology.

This paper presents an organized system for element-specific sample collection and handling of human blood (whole blood, serum or plasma, packed cells or erythrocytes) and urine also indicating a proper definition of the subject and sample. Harmonized procedures for collection, preparation, analysis and quality control are suggested. The aim is to assist scientists worldwide to produce comparable data which will be useful on a regional, national and international scale. The guidelines are directed to the elements aluminium, arsenic, cadmium, chromium, cobalt, copper, lead, lithium, manganese, mercury, nickel, selenium and zinc. These include the most important elements measured for their occupational or clinical significance, and serve as examples of principles that will guide development of methods for other elements in the future.

Blood Specimen Collection↗
PubMed1996

Behavioral determinants of occupational exposure to chemical agents.

In the demand-control model (see T. Theorell & R. A. Karasek, 1996), it is hypothesized that workers in active jobs (high demands-high decision latitude) can exert effective coping strategies when confronted with environmental stessors. Thus, when exposed to similar levels of a chemical agent, lower concentrations of this agent in blood could be expected in these workers in comparison with workers in passive jobs. This theory was tested in 2 studies of lead-exposed workers: 18 male Caucasian workers from an electric accumulatory factory and 18 male Caucasian workers from a lead smelting factory. The results did not follow the hypothesized outcomes. In the work environment of the workers in active jobs, lower concentrations of lead in air were measured, but higher levels of lead in blood were observed in these workers. The opposite was true of workers in passive jobs. Differences in hygienic behavior at work may explain these unexpected results.

Adaptation, Psychological↗
PubMed1995

The determination of alpha 1-microglobulin by means of an automated latex immunoassay.

Polystyrene (latex) particles coated with human anti-alpha 1 microglobulin antibodies are used in an automated "kinetic" assay for alpha 1-microglobulin in urine. For values below 12 mg/l, there was no significant difference between two kinds of standard, but above 12 mg/l the results depend on the origin of the alpha 1-microglobulin standard. Correlation between values obtained with both standards was good (r2 = 0.968). The method has a between-run imprecision (CV) of 11-16%. Comparison with two commercial enzyme immunoassays gave a bias of -10% to +40%, while two nephelometric methods differed by 0% to 23%, possibly because the standards used in these methods were of different origin. These results indicate the necessity of standardization of the determination of alpha 1-microglobulin. The detection limit of our method was 0.8 mg/l, enabling the application of the method for epidemiological investigations.

Alpha-Globulins↗
PubMed1994

Estimation of pooled reference values for cadmium in blood using meta-analysis and TRACY criteria.

Reference values for blood-cadmium levels (B-Cd) are available for only a limited number of geographical areas and for particular population strata (sex, age, smoking habits). This paper, in agreement with the TRACY guidelines, describes and discusses the criteria used to rank published papers on reference values for cadmium retrieved by Medline and Toxline between 1976 and 1991. The TRACY criteria deal with the grading of published papers in terms of their suitability for calculating provisional reference values. Only four out of 18 papers were considered suitable for the TRACY project. The four articles were finally used via meta-analysis to provide provisional reference values for smokers and non-smokers. The comparison of results obtained using published statistics and individual data is used to discuss the appropriateness of meta-analysis in the case of cadmium. Due to the availability of large enough studies and to the clear differences across countries, the suitability of a compound upper reference limit to B-Cd levels seems limited.

Adult↗
PubMed1994

Tentative reference values for nickel concentrations in human serum, plasma, blood, and urine: evaluation according to the TRACY protocol.

Published reports of Ni concentrations in human serum or plasma, whole blood, and urine have been reviewed in order to establish a database of reference values. In keeping with the TRACY program as previously applied to Hg, reports were evaluated in the categories of description of sample population, specimen collection and processing, analytical methods, and data presentation. Based on these considerations, eight studies of Ni in serum were deemed suitable for establishing reference levels in the general population. In five of these studies, the mean values for serum Ni concentration were < 0.3 microgram/l and the upper limits were < or = 1.1 micrograms/l. Six studies of Ni in urine were found suitable, and in four of these the mean values of Ni were < or = 2.0 micrograms/l and the upper limits were < or = 6.0 micrograms/l. Fewer studies on Ni in whole blood have been reported, and the Ni content of blood remains uncertain.

Humans↗
PubMed1994

Comparison of renal function parameters in the assessment of cis-platin induced nephrotoxicity.

The early renal function parameters (RFP), i.e. urinary alanine aminopeptidase (AAP), beta-galactosidase (beta GAL), N-acetyl-beta-D-glucosaminidase (NAG), retinol-binding protein (RBP), albumin (ALB), total protein (TP) and the conventional RFP plasma creatinine were assessed in 8 patients before and during treatment with the nephrotoxic antitumor agent cis-platin. Plasma creatinine increased during treatment with cis-platin. In all patients, acute tubular damage was revealed by early RFP. Albumin and total protein excretion patterns suggested alterations in glomerular function. The cumulative change in RBP excretion was related to plasma creatinine concentrations following cis-platin administration. The present study demonstrates that urinary RBP is a valuable parameter for the early assessment of cis-platin-induced nephrotoxicity.

Acetylglucosaminidase↗
PubMed1993

Hygienic behaviour in chromium plating industries.

The impact of hygienic behaviour on the uptake of chromium has been studied in two small chromium plating factories. The correlation between the environmental monitoring measure (Cr-A) and the biological monitoring measure (Cr-U) varied between the two factories. In one factory (I) the correlation between Cr-U and Cr-A was 0.68 (P < 0.001), while in the other factory (II) it was negative (r = -0.64, P = 0.03). However, in both populations a significant impact of hygienic behaviour on the variance in Cr-U levels could be detected. In factory I, explained variance could be enhanced to R2 = 0.94 (P < 0.001) when considering expressions of hygienic behaviour. In factory II, a strong relation proved to exist between Cr-U and dermal uptake. For the various questions referring to skin problems and possible dermal uptake, the correlation with Cr-U is up to 0.70 (P = 0.03). When comparing the results for the two factories, it is shown that in addition to individual differences in hygienic behaviour, general hygienic conditions also have an impact on uptake of chromium. In factory II, where many efforts were made to prevent exposure to chromium, Cr-U was significantly lower than in factory I (P < 0.001).

Adult↗
PubMed1992

A comparison of dilution adjustment methods for urinary enzymes.

Urinary dilution adjustment methods can be used to reduce the intra-individual variability in concentrations of metals and other substances in urine due to variability in urinary flow. In this study linear and non-linear dilution adjustments with urinary flow, creatinine (CREAT) and urinary density (UD) were compared for the urinary enzymes alanine amino peptidase (AAP), beta-galactosidase (beta GAL) and N-acetyl-beta, D-glucosaminidase (NAG). The most optimal dilution adjustment for AAP was: AAPadjusted = AAPmeasured/(CREATmeasured)0.824 The optimal dilution adjustment for beta GAL was: beta GALadjusted = beta GALmeasured/(CREATmeasured)0.878 For NAG the optimal dilution adjustment parameter was the conventional linear adjustment with SG. It could not be determined whether urinary dilution methods can be useful for population based reference intervals of urinary enzymes. If personal reference intervals can be calculated, urinary dilution adjustment methods may be useful by reduction of intraindividual variability.

Acetylglucosaminidase↗
PubMed1992

The World Health Organization study on health effects of exposure to cadmium: morbidity studies.

Studies according to the protocol of the WHO Regional Office for Europe were performed in Germany, the Netherlands and Belgium. Pilot studies were performed in Czechoslovakia, Hungary and Poland. The results of the Belgian study are described elsewhere; some striking results of the other studies are reported here. The highest levels of cadmium in blood (Cd-B) were reported in a cadmium-polluted area in Hungary, the lowest in a non-polluted urban area. In Poland, levels were enhanced in polluted and non-polluted areas. The highest levels of cadmium in urine (Cd-U) were found in Hungary, the lowest in the Netherlands. In nearly all the studies significant increases in both Cd-B and Cd-U were found in cadmium-polluted areas. The picture is less clear with regard to the biological effect parameters. The renal parameters were sometimes significantly enhanced for the polluted areas, but sometimes the opposite was reported. Because of the many confounding variables, stratification at least by smoking behaviour, sex and age is necessary if firm conclusions are to be reached. A better approach, however, is to use multivariate regression analysis. This technique allowed the calculation of the relation between Cd-U and age in the German and Dutch studies, and between Cd-U and age in the German and Dutch studies, and between Cd-U and NAG, AAP, Alb-U and Creat-S levels.

Adult↗
PubMed1991

An inverse lead air to lead blood relation: the impact of air-stream helmets.

At a secondary smelter (24 smelting workers, 13 refinery workers), data on exposure to lead were collected by systematic observation of hygienic behaviour, a questionnaire, personal sampling of lead dust in ambient air (PbA) and determination of lead in the blood level (PbB). The smelting workers showed a negative relation between PbA and PbB. The 53% variance in PbB levels in the smelting workers can be explained by the combination of PbA, the percentage of time an air-stream helmet is worn, the frequency of cigarette smoking at the workplace and the amount of spitting. Air-stream helmets and spitting contribute to a lower PbB, whereas smoking contributes to a higher PbB. Moreover, expected PbB levels were computed by using several regression equations for the relation between PbA and PbB, as suggested in the Final OSHA Standard for Occupational Exposure to Lead (OSHA 1978). As the percentage of time an air-stream helmet is worn increases, the deviation from the expected PbB falls substantially. The refinery workers showed the expected weak positive correlation coefficient between PbA and PbB. No direct relation between the PbB level and the observed hygienic behaviour could be established. However, there was a positive relation between the level of education and the level of PbB. Moreover, the level of education was related to the frequency of eating at the workplace and negative as far as the percentage of time gloves are worn is concerned. Our conclusion is that hygienic behaviour is a major factor that modifies the relation between PbA and PbB in groups of workers.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Work hygienic behaviour as modifier of the lead air-lead blood relation.

Knowledge of hygienic behaviour at the workplace appears to explain the low correlation between external and internal exposure. Differences in hygienic behaviour explain at least the same magnitude of variation in levels of lead in blood as the level of lead in air. Adding hygienic behaviour to the lead air-lead blood model increases the accuracy of prediction of PbB. In this study, the frequency of putting on/off gloves and the frequency of hand-mouth nose/shunt are the strongest modifiers of the PbA-PbB relation. In general, the actual behaviour of workers exposed to chemical agents may explain the often observed poor or moderate relationships between environmental and biological monitoring parameters of chemical exposure in occupational health studies.

Air Pollutants, Occupational↗