Olle Nygren

Sampling and analysis considerations for the determination of hexavalent chromium in workplace air

Airborne hexavalent chromium (Cr[VI]) is a known human respiratory carcinogen and allergen. Workers in a variety of industries may be exposed to airborne hexavalent chromium, with exposures frequently occurring via inhalation and/or dermal contact. Analytical methods for the measurement of Cr(VI) compounds in workplace samples, rather than for the determination of total elemental chromium in workplace air, are often desired because exposure limit values for Cr(VI) compounds are much lower than for total Cr. For years, sampling and analytical test methods for airborne Cr(VI) have been investigated so as to provide means for occupational exposure assessment to this highly toxic species. Inter-conversion of trivalent chromium (Cr[III]) and Cr(VI) can sometimes occur during sampling and sample preparation, and efforts to minimize unwanted redox reactions involving these chromium valences have been sought. Because of differences in toxicity, there is also interest in the ability to differentiate between water-soluble and insoluble forms of Cr(VI), and procedures that provide solubility information concerning Cr(VI) compounds have been developed. This paper reviews the state of the art concerning the measurement of airborne Cr(VI) compounds in workplace aerosols and related samples.

Exposure to anti-cancer drugs during preparation and administration. Investigations of an open and a closed system

Systems for the preparation and administration of drugs are designed to ensure that the drug is not contaminated. They do not necessarily consider the work environment for the medical staff and new techniques are therefore desirable. The aim of this work is to compare a new closed system for the preparation and administration of drugs with the traditional technique with regard to airborne emission and surface spillage of drugs. Platinum, determined using adsorptive voltammetry, was used as the tracer for airborne emission. Air samples were collected during the preparation and administration, and the collected platinum on the filters was determined by adsorptive voltammetry. For determination of spills and leakage onto surfaces the radioisotope 99m-technetium was used as a tracer. The radiation from the isotope was determined on protective gloves and bench covers after preparation and administration. The mean airborne emission was 6 ng m(-3) with the closed system and 15 ng m(-3) with the traditional pump technique. The average surface spillage using the closed technique was 0.005 microL. This is significantly smaller than with the traditional technique, which resulted in an average spillage of 64 microL. Our results also show that the dominant part of the leakage is surface spillage. Inexperienced nurses could also adequately handle the closed system.

Speciation of chromium in tanned leather gloves and relapse of chromium allergy from tanned leather samples

There are concerns that wearing chromium tanned leather gloves can provoke a lapse of hand dermatitis in chromium sensitive patients. Various forms of chromium have different biological effects and the determination of total chromium (both soluble and insoluble), which often is used in clinical studies, may therefore not be an adequate measure of the adverse exposure. However, investigations, where dissolution of hexavalent chromium from leather gloves has been experimentally studied, could not been found in the literature. The aim of this pilot study was therefore to determine the total amount of chromium and the amount of sweat leachable chromium in different leather glove materials and also to apply samples of these materials in a patch test to chromium sensitive patients to see if they could provoke a reaction. The results showed tha chromium tanned leather contained about 3% (m/m) chromium. Chromium can also be found in dyed vegetable tanned leather, probably emanating from the leather dye. Small amounts (average 0.08% m/m) of leachable hexavalent chromium were found in both chromium and vegetable tanned leathers. Thus, the risk of relapse of chromium dermatitis cannot be disregarded and further studies on the causes of relapse of chromium dermatitis are necessary.

Spill and Leakage Using a Drug Preparation System Based on Double-Filter Technology

Occupational exposure to cytotoxic drugs has frequently been reported during recent years. Various drug-handling systems have been applied to reduce the spill and leakage that cause this exposure. Some of these systems have also been tested for spill and leakage using independent test methods. In this paper, a new drug-handling system has been tested for spill and leakage during drug preparation. The handling system, Tevadaptortrade mark, was tested using a modification of an independent test method, the Technetium test method, based on the use of Technetium m-99 as tracer substance. The test results showed that the spill was <100 nl for all 75 preparations and was <1 nl for 70 of the preparations. This is comparable with other tested drug-handling system, e.g. isolators, PhaSealtrade mark. The test shows that the Tevadaptor drug-handling system has similar performance as drug-handling systems regarded as closed systems.

Wipe sampling as a tool for monitoring aerosol deposition in workplaces

As a complement to traditional exposure assessment, monitoring deposition of aerosols can be a simple and quick screening method for identifying deposited aerosols. In this presentation examples of screening studies, based on wipe sampling in combination with adequate analytical techniques, are described. These screening methods are rapid, simple and easy to carry out. The examples given in this presentation show a broad applicability and the methods are proven useful for assessing aerosol distribution in the workplace as well as to identify target spots for more extensive assessment of a workers exposure situation.

Characterization of a nebulizer interface for flame atomic absorption spectroscopy

Abstract In this paper we describe and characterize a nebulizer “interface” for flame atomic absorption spectroscopy (FAAS). A nebulizer interface should provide for optimum coupling of analytical liquid flow techniques, e.g. flow injection analysis and liquid chromatography, to FAAS instruments. When the interface is used instead of one of the conventional nebulizer systems together with a FAAS instrument, a 3–5 times better characteristic concentration and detection limit were obtained for the test element Mn. The interface facilitates the coupling of analytical low-flow rate devices to FAAS instruments and simplifies the optimization of flame stoichiometry. The nebulizer interface provides for complete utilization of the sample (no waste). When the interface is used to connect a high performance liquid chromatography system to a FAAS instrument, the resulting increase in peak width is approximately 1 s.

Determination of trimethyllead salts in blood using high-resolution gas chromatography-graphite furnace atomic absorption spectrometry

A method for the determination of trimethyllead salts in human blood samples is described. The method is based on extraction, evaporation and butylation, followed by determination using combined high-resolution gas chromatography and graphite furnace atomic absorption spectrometry. A detection limit of 0.003 µg ml–1 in blood and good reproducibility and linearity within the analytical range required for real samples are obtained. This method, in combination with a previously presented method for the determination of tetramethyllead in blood, affords a procedure for biological monitoring of occupational exposure to tetramethyllead.

Development of a Method for Screening Spill and Leakage of Antibiotics on Surfaces Based on Wipe Sampling and HPLC-MS/MS Analysis

A screening method for determination of spill and leakage of 12 different antibiotic substances has been developed. The method is based on wipe sampling where the sampling procedure has been simplified for screening purposes. After sample processing, the antibiotic substances are determined by liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). Twelve antibiotic substances can be determined in the screening method: Cefadroxil, Cefalexin, Ciprofloxacin, Demeclocyklin HCl, Diaveridin, Doxycyklin, Enrofloxacin, Flukonazol, Metronidazol, Norfloxacin, Ofloxacin, and Trimetoprim. These substances are active components in antibiotic drugs frequently used in Sweden. For screening investigations using collection of wipe samples, good or acceptable performance was obtained for ten substances on three or more surface materials. Although not fully acceptable, useful performance for screening purposes was also obtained on the other surface materials and for the other substances, except Demeclocyklin HCl, on all surface materials. By employing a classification procedure, where the samples are divided into groups according to increasing contamination of the sample surfaces, screening samples and the contamination level can simply be compared. This classification procedure will also help to circumvent any deficiency in recovery performance for some substances and surface materials.

Validation and Application of Wipe Sampling and Portable XRF Analysis as an On-Site Screening Method for Assessment of Deposited Aerosols in Workplaces

Emission of metals in the form of aerosols constitutes a potential health risk in many working environments. Determination of deposited aerosols can be a useful tool for the assessment of aerosol distribution in the workplace and be a complement to more traditional exposure measurements. X-Ray fluorescence (XRF) is a common analytical method for elemental analysis of aerosols. By collection of deposited aerosols by wipe sampling followed by XRF analysis, the distribution of aerosols can be assessed. This paper describes the validation of a screening method for the assessment of aerosol distribution in workplaces. The method has been shown to have adequate performance for screening studies of deposited aerosols in workplaces and can, thus, be a useful complement to traditional occupational hygiene measurements. The applicability for screening measurements is demonstrated by assessment of the distribution of welding fumes in a welding workshop and of a cytotoxic drug in a drug preparation room at an oncology clinic. Being rapid and simple, it will be a useful tool to identify target spots for more extensive assessment of the workers exposure situation.

Determination of lead in blood using flow injection and a nebuliser interface for flame atomic absorption spectrometry

An improved system for the determination of lead in blood by flame atomic absorption spectrometry has been developed. The system is based on flow injection, a nebuliser interface and a computer signal evaluation system. The system improves the detection limit 12-fold compared with that obtained by unmodified instrumentation. A detection limit of 0.06 µM was obtained using a 10-year-old instrument. With a relative standard deviation of 5% at normal lead levels in blood, even small changes in the lead concentration can be determined with adequate precision and accuracy.