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W L de Kort

Publications and source records attributed to W L de Kort.

15 recordsLinked to original sources
PubMed1998

Proposal for the assessment of quantitative dermal exposure limits in occupational environments: Part 1. Development of a concept to derive a quantitative dermal occupational exposure limit.

Dermal uptake of chemicals at the workplace may contribute considerably to the total internal exposure and so needs to be regulated. At present only qualitative warning signs--the "skin notations"--are available as instruments. An attempt was made to develop a quantitative dermal occupational exposure limit (DOEL) complementary to respiratory occupational exposure limits (OELs). The DOEL refers to the total dose deposited on the skin during a working shift. Based on available data and experience a theoretical procedure for the assessment of a DOEL was developed. A DOEL was derived for cyclophosphamide and 4,4-methylene dianiline (MDA) according to this procedure. The DOEL for MDA was tested for applicability in an actual occupational exposure scenario. An integrated approach is recommended for situations in which both dermal and respiratory exposures contribute considerably to the internal exposure of the worker. The starting point should be an internal health based occupational exposure limit--that is, the maximum dose to be absorbed without leading to adverse systemic effects. The proposed assessment of an external DOEL is then either based on absorption rate or absorption percentage. The estimation of skin penetration seems to be of crucial importance in this concept. If for a specific substance a maximal absorption rate can be estimated a maximal skin surface area to be exposed can be assessed which may then serve the purpose of a DOEL. As long as the actual skin surface exposed is smaller than this maximal skin surface area the internal OEL will not be exceeded, and therefore, no systemic health problems would be expected, independent of the dermal dose/unit area. If not, the DOEL may be interpreted as the product of dermal dose/unit area (mg/cm2) and exposed skin surface area (cm2). The proposed concept for a DOEL is relevant and can be made applicable for health surveillance in the occupational situation where dermal exposure contributes notably to the systemic exposure. Further research should show whether this concept is more generally applicable.

Humans↗
PubMed1993

Quality assessment of occupational health services instruments.

Interest in the quality of instruments for occupational health services is growing as a result of European legislation on preventive services stressing, for example, risk identification and assessment. The quality of the services can be enhanced when the quality of the applied instruments can be judged and improved. To judge quality aspects of instruments, a basic draft scheme and criteria are presented. A first category of criteria covers measurement objective and study design and comprises for example sample strategy and data aggregation level. Technical quality aspects are validity, reliability, standardization and precision. Acceptability of an instrument by employees, employers and professionals belongs to the process quality. At last, strategic quality or presumed utility has to be assessed. As an illustration four instruments have been judged: periodic occupational health surveys, pre-employment medicals, the company audit on work and health, and specific working conditions assessment instruments. Finally the presented basic scheme and criteria are brought into discussion.

Europe↗
PubMed1992

The isolated blood-perfused pig ear: an inexpensive and animal-saving model for skin penetration studies.

To overcome most of the disadvantages of current models to investigate percutaneous penetration of drugs or toxic substances, a model is proposed here based on the isolated pig ear, which is obtained at the slaughterhouse, and perfused with oxygenated blood from the same pig. To determine the viability of the preparations, we measured glucose consumption and lactate production as metabolic parameters, Na+ and K+ ions, as well as lactate dehydrogenase activity in blood as markers for cell damage, whereas vasomotor reactivity was assessed by administering noradrenaline and isoxsuprine. After 60 min of equilibration, only insignificant changes in these parameters were observed during the subsequent 3-hr test period (longer periods were not tested). A slight weight increase was noted during the total period 4 hr, presumably due to slight edema formation. On the basis of several types of measurements, such as in vivo blood flow and ear temperature and in vitro glucose metabolism, standard procedures were developed. It is concluded that this technique offers an easy to handle, cost-efficient, and animal-saving model for skin penetration studies that lacks most of the disadvantages of existing models.

Animal Testing Alternatives↗
PubMed1992

Agreement on medical fitness for a job.

Five experienced occupational physicians independently reviewed the uniformly structured, concise records of 180 applicants who had applied for a job in one of three categories. All had undergone a preemployment medical examination by the Governmental Occupational Health and Safety Service. Agreement was assessed by calculating the percentage of disagreement and Cohen's kappa. Agreement between the five panel physicians and between the panel physicians and the Service appeared to be poor, with overall percentages of disagreement of 31 and 37%, respectively, and kappa values of 0.38 and 0.37, respectively. On the average 31% of the applicants judged as unfit by one physician had been assessed as fit by the others, whereas agreement was only marginally better when detailed medical criteria for fitness were available. Lack of consensus on the medical fitness of an applicant, as evidenced by this study, suggests that the validity of such a judgment may be questionable even when detailed fitness criteria are available.

Adult↗
PubMed1991

Preemployment medical examinations in a large occupational health service.

Several hundreds of thousands of preemployment medical examinations are performed in The Netherlands each year, with the objective of screening for obvious risks for the applicants or others. Neither the efficacy of these examinations nor determinants for rejection are known. Altogether 101,754 preemployment medical examinations of applicants for governmental functions were analyzed. For one-fifth of the applicants some medical diagnosis was recorded. The overall rejection percentage was 0.6%, being highest for job categories involving public safety and high physical demands, but never exceeding 4%. Age was positively correlated with rejection percentage. Except for the diagnostic category "disorders of the musculoskeletal system" no relation between diagnostic category and job demands was apparent. Medical diagnoses frequently encountered among rejected applicants were also common among successful applicants. If selection aiming at reducing absenteeism or work disablement is considered to be the only goal of preemployment medical examinations, then their efficacy appears to be low for many job categories.

Absenteeism↗
PubMed1988

Blood lead and blood pressure: some implications for the situation in The Netherlands.

Studies performed earlier have shown a positive relation between blood lead (a parameter for lead body burden) and blood pressure, whereas such a relation between urine cadmium (a parameter for cadmium body burden) and blood pressure could not be shown. Median (i.e., 50th percentile, P50) blood levels in the general population in the Netherlands are in the range of 80 to 150 micrograms/L. Persons occupationally exposed to lead show median blood lead levels that may exceed 400 micrograms/L. To study causality, a prospective study among lead workers is desired.

Adult↗
PubMed1988

The use of atropine and oximes in organophosphate intoxications: a modified approach.

Usually intoxications with cholinesterase inhibitors are treated with large dosages of atropine. Furthermore oxime treatment, if applicable, is generally discontinued after one to two days. Two cases of severe anticholinesterase intoxication are presented. In both cases administration of oximes were part of the treatment. The first patient showed relapse cholinergic symptoms when administration of oximes was stopped after one day. In the second patient, where oximes were administered continuously during six days, no relapse cholinergic symptoms occurred. Based on pharmacological as well as on toxicokinetic considerations, and supported by animal experimental data, a continued oxime treatment, if appropriate, can be advocated, whereas the use of atropine should be minimized.

Adult↗
PubMed1988

Acute intoxications during work.

Information on acute intoxications during work in the Netherlands has been gathered from 4 sources during a 1-year period: 1. The registration of occupational accidents of the Directorate-General of Labour, by reviewing reports on accidents involving chemicals; 2. The Netherlands Poison Control Centre of the National Institute for Public Health and Environmental Hygiene, by tracing back consulting physicians; 3. The Dutch Centre for Health Care Information, by searching their data base for hospital admissions with relevant admission diagnoses and 4. A large Occupational Health Service, which for this purpose recorded incident cases in the population under care. During the period of investigation 5 deaths were reported: 1 case of hydrogen cyanide intoxication, 1 case of carbon dioxide intoxication, and 3 cases of hydrogen sulfide intoxication in combination with oxygen deficiency (nearby a liquid manure tank). At least 690 (supposed) acute intoxications during work occurred, which in 84 cases resulted in hospital admission. The total number of hospital admissions for supposed unintentional acute intoxications by chemicals, usually encountered in workplaces, in the Netherlands in 1984 was at least 477. Substances most often involved belonged to the groups of pesticides, lung and/or skin irritant liquids/vapors/gases and asphyxiants. The working branches most often involved were agriculture and market gardening sectors, (chemical) industries, repair and retail trade and some governmental services (police, fire brigade, defense personnel). The results show considerable underreporting in official statistics on acute intoxications during work.

Female↗
PubMed1987

Occupational exposure to lead and blood pressure: a study in 105 workers.

A group of workers, occupationally exposed to lead and cadmium compounds (n = 53), was compared to a group of workers not exposed to these metals (n = 52). The average values of systolic, diastolic, and mean blood pressure were found to be higher in the exposed group (p less than 0.05). In contrast with the correlation between CdU and blood pressure, the correlation between PbB and systolic and mean blood pressure remained statistically significant after controlling for age and pulse rate (r = 0.22, p less than 0.05). The prevalence of potential hypertension (defined as systolic blood pressure greater than or equal to 160 mm Hg and/or diastolic blood pressure greater than or equal to 95 mm Hg and/or under treatment for hypertension) was higher in the exposed group, but the observed relative risk was not statistically significant: relative risk = 1.91 (95% confidence limits, 0.90-4.05). Furthermore, a significant correlation between PbB and Hgb (r = -0.28, p = 0.004) was observed. Differences in kidney function, as assessed in this study, were not detected.

Adult↗
PubMed1987

Exposure of the skin to methyl bromide: a study of six cases occupationally exposed to high concentrations during fumigation.

1 The effects of exposure of the skin to high concentrations of methyl bromide were studied in 6 cases, who had been unintentionally exposed. 2 Exposure to high concentrations of methyl bromide (approximately 40 g/m3) for 40 min can lead to redness and blistering of the skin. This cannot be prevented by wearing standard protective clothing. 3 Skin lesions show a preference for relatively moist skin areas. 4 Plasma bromide levels were highest immediately following exposure (mean 9.0 +/- 1.4 mg/l) and fell in subsequent hours (mean 6.8 +/- 2.3 mg/l 12 h after the exposure), suggesting absorption of (methyl) bromide through the skin. 5 No systemic effects were noted in this series. 6 Fumigation with methyl bromide should not be done in such a way as to require the presence of workers inside closed areas, where methyl bromide is released.

Adult↗