Workplace Samples Research Articles

Collection, Validation and Generation of Bitumen Fumes for Inhalation Studies in Rats Part 2: Collection of Bitumen Fumes from Storage Tanks

The objective of the study described in this and an accompanying series of papers was to develop a laboratory generated exposure atmosphere to be used for chronic inhalation toxicity studies in rats that resembles, as closely as possible, personal exposures seen by workers during road paving operations. To achieve this objective, atmospheric workplace samples were collected at road paving worksites and compared analytically with bitumen fume samples collected from the headspace of hot bitumen storage tanks. In Preiss et al. (2006) the collection and analysis of workplaces samples is described. This contribution describes the strategy for the in-line extraction of a suitable fraction of bitumen fume collected from the headspace of a bitumen storage tank and the comparison of the collected condensate to workplace samples. Results show that is possible to develop a collecting procedure that allows sampling from hot bitumen storage tanks in an operational asphalt mixing plant. The sampling procedure has been optimized to collect material that matches the workplace samples as closely as possible. The comparison to workplace samples has been performed using parameters that can be analyzed in both the workplace samples and the bitumen fume condensate collected from the tanks. Boiling point distribution (BPD), UV fluorescence (UV-Fl) and content of individual polycyclic aromatic hydrocarbons (PAH) were selected as parameters. The BPD of the final collected bitumen fume condensate did not differ by more than 17 degrees C from any point on the average BPD curve of the workplace samples, in the range from 5 to 95%. UV-Fl of the bitumen fume condensate nearly exactly matched the average UV-Fl of the workplace samples. However, the sum of the 17 PAHs analyzed in the test samples, compared to the mass of the condensate, is lower by a factor of approximately 3 than the sum of the 17 PAHs in some personal samples compared to the mass of Total Organic Matter (TOM). It has to be recognised that during the collection of the workplace samples, despite all efforts a number of the workers who carried a personal sampler could not be prevented from smoking.

Collection, Validation and Generation of Bitumen Fumes for Inhalation Studies in Rats Part 1: Workplace Samples and Validation Criteria

Undertaking a chronic inhalation study on bitumen fume presents a challenge in terms of generating large amounts of representative fume. The objective of the study described in this and the following contributions was to collect sufficient fume and develop a laboratory-generated exposure atmosphere that resembles, as closely as possible, personal exposures seen in workers during road paving operations, for use in chronic inhalation toxicity studies in rats. To achieve this goal, atmospheric workplace samples were collected at road paving work sites both by Shell Global Solutions, Int. (Shell) and by the 'Berufsgenossenschaftliches Institut für Arbeitssicherheit' (BIA, Germany) and compared with bitumen fume condensate samples collected from the head space of hot bitumen storage tanks. Part 1 describes the collection and analysis of personal and static workplace samples. Different sampling methods were also used to allow a comparison of the standard German sampling method with the most common industry method used. Samples were analyzed by Shell, BIA and by the Fraunhofer Institute of Toxicology and Experimental Medicine (Fh-ITEM, Germany) using different methods. Parameters determined were: total particulate matter (TPM), benzene soluble matter (BSM), semi-volatiles (SV), total organic matter (TOM), boiling point distribution (BPD), polycyclic aromatic hydrocarbons (PAHs) and UV fluorescence (UVF). The BPD of personal and static samples had almost identical start and end points, but static samples show a tendency towards an increase in amounts of higher boiling point compounds. Personal samples generally show higher PAH concentrations than comparable static samples. The results of the analysis of personal workplace samples were used to establish validation/acceptance criteria for the bitumen fume condensate sampled from storage tanks for the inhalation study, which is described in a further publication. The criteria involve a range of parameters that can be analyzed in both workplace samples and samples of tank fume condensate: BPD, UVF and content of individual PAHs were selected as parameters.

Validation of a standardized portable fluorescence method for determining trace beryllium in workplace air and wipe samples

Beryllium is widely used in industry for its unique properties; however, occupational exposure to beryllium particles can cause potentially fatal disease. Consequently, exposure limits for beryllium particles in air and action levels on surfaces have been established to reduce exposure risks for workers. Field-portable monitoring methods for beryllium are desired in order to facilitate on-site measurement of beryllium in the workplace, so that immediate action can be taken to protect human health. In this work, a standardized, portable fluorescence method for the determination of trace beryllium in workplace samples, i.e., air filters and dust wipes, was validated through intra- and inter-laboratory testing. The procedure entails extraction of beryllium in 1% ammonium bifluoride (NH(4)HF(2), aqueous), followed by fluorescence measurement of the complex formed between beryllium ion and hydroxybenzoquinoline sulfonate (HBQS). The method detection limit was estimated to be less than 0.02 microg Be per air filter or wipe sample, with a dynamic range up to greater than 10 microg. The overall method accuracy was shown to satisfy the accuracy criterion (A< or = +/-25%) for analytical methods promulgated by the US National Institute for Occupational Safety and Health (NIOSH). Interferences from numerous metals tested (in >400-fold excess concentration compared to that of beryllium) were negligible or minimal. The procedure was shown to be effective for the dissolution and quantitative detection of beryllium extracted from refractory beryllium oxide particles. An American Society for Testing and Materials (ASTM) International voluntary consensus standard based on the methodology has recently been published.

Multiple Aspects of Hair Analysis for Opiates: Methodology, Clinical and Workplace Populations, Codeine, and Poppy Seed Ingestion

Levels of morphine, 6-monoacetylmorphine (MAM) and codeine in hair in both clinical and workplace subjects are presented. Aggressive wash procedures, consisting of 1 isopropanol wash, three 30-min, and two 1-h buffer washes, followed by digestion, extraction and confirmation of digested samples, resulted in values from the cutoff of 2 ng morphine/10 mg hair to greater than 200 ng/10 mg hair. Both morphine and MAM were present above the cutoff in all hair samples from 69 clinical subjects. Only 39 of the 69 heroin-using subjects had urine tests positive for 6-MAM. In a study of morphine in hair following poppy seed consumption, ten subjects ingested 150 g of poppy seed over 3 weeks. Urine samples were collected on the days of poppy seed ingestion and hair samples were taken in the 5th week of the study. The range among the 10 subjects of the highest urine value for each subject was 2929 to 13,827 ng morphine/mL. Hair morphine levels were 0.05-0.48 ng/10 mg hair (average 0.17 ng/10 mg hair). Hair opiate levels of workplace subjects ranged somewhat lower than those of clinical subjects. While all clinical hair samples contained MAM, many workplace samples did not. From workplace samples, a maximum amount of morphine likely to be present from codeine use was 0-3.7% of the codeine in the hair.

Interlaboratory Evaluation of a Portable Fluorescence Method for the Measurement of Trace Beryllium in the Workplace

Abstract Researchers at Los Alamos National Laboratory (LANL) developed a field-portable fluorescence method for the measurement of trace beryllium in workplace samples such as surface dust and air filters. The technology has been privately licensed and is commercially available. In cooperation with the Analytical Subcommittee of the Beryllium Health and Safety Committee, we have carried out a collaborative interlaboratory evaluation of the LANL field-portable fluorescence method. The interlaboratory study was conducted for the purpose of providing performance data that can be used to support standard methods. Mixed cellulose ester (MCE) membrane filters and Whatman 541 filters were spiked with beryllium standard solutions so that the filters spanned the range ≈0.05 − ≈0.5 µg Be per sample. Sets of these filters were then coded (to ensure blind analysis) and sent to participating laboratories, where they were analyzed. Analysis consisted of the following steps: 1. Removal of the filters from transport cassettes and placement of them into 15-mL centrifuge tubes; 2. mechanically-assisted extraction of the filters in 5 mL of 1% ammonium bifluoride solution (aqueous) for 30 min; 3.–4. filtration and transfer of sample extract aliquots (100 µL) into fluorescence cuvettes; 5. introduction of 1.9 mL of detection solution (to effect reaction of the fluorescence reagent with beryllium in the extracted sample); and 6. measurement of fluorescence at ≈475 nm using a portable fluorometer. This work presents performance data in support of a procedure that is targeted for publication as a National Institute for Occupational Safety and Health (NIOSH) method and as an ASTM International standard.

Multi-Rater or 360-degree Emotional Intelligence Assessment

In this paper we discuss the potential utility of multi-rater or 360-degree measured EI over self-reported and ability measured EI. We then discuss the development of a workplace 360 measure of emotional intelligence designed specifically for development purposes. Several research studies testing workplace samples are presented which examine the internal consistency reliability of the rater forms of the 360 instrument; compare the means and standard deviations of self- and other-rated EI; and the relationship between how people rate themselves on the instrument and how they rate others. The research findings demonstrate the utility of multi-rater 360-degree EI assessment instruments, which is discussed specifically in terms of leadership development.

Amphetamines in washed hair of demonstrated users and workplace subjects

In a study of volunteer subjects from drug rehabilitation programs, methamphetamine and amphetamine levels were determined in the hair of 40 subjects who had produced MS-confirmed methamphetamine-positive urine results. The samples were tested by radioimmunoassay and analyzed by LC/MS/MS after being washed with the 3.75-h wash procedure developed by this laboratory. In addition, results of non-user and workplace samples are presented. In workplace samples, levels of methamphetamine, amphetamine, methylenedioxy-methamphetamine (MDMA), and methylenedioxyamphetamine (MDA), are reported. The range of methamphetamine levels in the clinical samples (170–34,400 pg/mg hair) was not different from the workplace population (from less than the cutoff of 500 pg/mg to >20,000 pg/mg hair), but the workplace population had a lower percentage of high levels of drug. Amphetamine levels were found to vary widely in both populations, at all levels of methamphetamine. In the clinical population, no samples were positive for MDMA; in MDMA-positive workplace samples, the levels ranged from below the cutoff of 500 to >20,000 pg/mg, with MDA levels varying widely, similar to amphetamine levels in methamphetamine-positive samples.

Comorbid mental disorders account for the role impairment of commonly occurring chronic physical disorders: results from the National Comorbidity Survey.

Most health and work productivity studies have focused on individual conditions without considering comorbidity. We illustrate the implication of this neglect by examining the effects of comorbid mental disorders on role impairment (number of sickness absence and work cut-back days in the past month) among people with chronic physical disorders. A nationally representative household survey of 5877 respondents assessed current mental and physical disorders and role impairments. Four physical disorders were sufficiently common to be studied: hypertension, arthritis, asthma, and ulcers. All 4 physical disorders were associated with significant role impairments in bivariate analyses. However, further analysis showed that these impairments were almost entirely confined to cases with comorbid mental disorders. Effectiveness trials in workplace samples are needed to evaluate the cost-effectiveness of treating comorbid mental disorders among workers with chronic physical disorders.

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.

Relationship between environmental exposure to toluene, xylene and ethylbenzene and the expired breath concentrations for gasoline service workers.

This study evaluated the relationship between the breath concentrations of, and personal exposure to, toluene, xylene and ethylbenzene of thirty workers from ten gasoline stations. Personal exposure air samples and workplace samples were collected simultaneously. Each subject provided a sample of exhaled breath after his or her personal exposure air was sampled. Twenty-five personal air, 17 workplace and 30 breath samples were collected in this study. Results indicated that breath concentrations of toluene and xylene were significantly correlated with personal monitoring concentrations. Furthermore, multiple regression analysis showed that exhaled toluene levels were highly influenced by personal toluene concentrations and the amount of personal gasoline sold (r2 = 0.762), while exhaled xylene levels depended on wind speed and personal xylene exposure concentrations (r2 = 0.665). Exhaled ethylbenzene levels were too low to present a relationship between concentrations and personal exposure levels. The exhaled toluene, xylene and ethylbenzene concentrations ranged from 4.3 to 41.8, 0.9 to 13.9, and 0.2 to 6.5 ppb, and the corresponding personal monitoring concentrations ranged from 60.3 to 572.3, 16.4 to 156.6, and 10.7 to 136.6, respectively. The average number of symptoms per person, according to neurotoxic questionnaire 16 (abbreviated as Q16) was 4.1 and six workers showed over six symptoms in Q16. This study suggests that exhaled toluene and xylene levels are suitable for use as biological exposure indices even at the ppb-level of exposure. Gasoline service workers are exposed to high levels of volatile organic compounds (VOCs) and the potential threats to their neurological systems deserve further investigation.

The Assessment of Counterproductive Tendencies by Means of the California Psychological Inventory

The authors developed an 80‐item scale to measure counterproductive tendencies, using items on the California Psychological Inventory (CPI), Form 434, and choosing items on the basis of their correlations, in a sample of 1,019 university undergraduates, with a self‐report instrument measuring counterproductive behaviors. A factor analysis of this criterion instrument revealed nine underlying dimensions. Analyses of scores on the new scale revealed significant gender differences (males higher) and yielded separate‐gender norms for four populations of interest. Internal‐consistency and test‐retest reliability estimates ranged between .80 and .90 across five samples. Correlations with standard CPI scales and domain and facet scales from the NEO PI‐R provided evidence of construct validity. Estimated true criterion‐related validity for the scale (a) averaged .60 in a student sample against the self‐report counterproductive‐behavior criterion, (b) was .35 against rated counterproductive job behavior in an employee sample, and (c) ranged as high as .36 against several other job‐performance ratings in two additional workplace samples.

Dustiness of Different High-Temperature Insulation Wools and Refractory Ceramic Fibres

Recent regulations are encouraging the replacement of older types of man-made mineral fibre by more soluble and, thus, less biopersistent compositions. In order for there to be any health benefits from this policy and to gain maximum benefit from such substitutions, the use of the new materials should not increase exposure. The work reported here was undertaken to investigate the use of new high-temperature glass insulation wools in place of refractory ceramic fibres (RCF). Airborne fibre levels occurring during the manufacture of both RCF and calcium magnesium silicate wools (CMS) were compared using measurements of genuine workplace exposure from a routine monitoring operation on the same plant. Exposures during use were compared in one customer facility where RCF and CMS blankets were used for the same task. Further comparisons were made in a laboratory test of dustiness using a "shaking box test". For some manufacturing tasks there are only a few workplace samples and there are few opportunities for genuine comparisons with both RCF and CMS in identical uses. However, both materials produced very similar exposure levels during manufacture, use and in the laboratory test. The novel magnesium silicate fibre was significantly dustier in the laboratory test.

Dustiness of different high-temperature insulation wools and refractory ceramic fibres

Recent regulations are encouraging the replacement of older types of man-made mineral fibre by more soluble and, thus, less biopersistent compositions. In order for there to be any health benefits from this policy and to gain maximum benefit from such substitutions, the use of the new materials should not increase exposure. The work reported here was undertaken to investigate the use of new high-temperature glass insulation wools in place of refractory ceramic fibres (RCF). Airborne fibre levels occurring during the manufacture of both RCF and calcium magnesium silicate wools (CMS) were compared using measurements of genuine workplace exposure from a routine monitoring operation on the same plant. Exposures during use were compared in one customer facility where RCF and CMS blankets were used for the same task. Further comparisons were made in a laboratory test of dustiness using a “shaking box test”. For some manufacturing tasks there are only a few workplace samples and there are few opportunities for genuine comparisons with both RCF and CMS in identical uses. However, both materials produced very similar exposure levels during manufacture, use and in the laboratory test. The novel magnesium silicate fibre was significantly dustier in the laboratory test.

Beryllium Exposure Control Program at the Cardiff Atomic Weapons Establishment in the United Kingdom.

The Cardiff Atomic Weapons Establishment (AWE) plant, located in Cardiff, Wales, United Kingdom, used metallic beryllium in their beryllium facility during the years of operation 1961-1997. The beryllium production processes included melting and casting, powder production, pressing, machining, and heat and surface treatments. As part of Cardiff's industrial hygiene program, extensive area measurements and personal lapel measurements of airborne beryllium concentrations were collected for Cardiff workers over the 36-year period of operation. In addition to extensive air monitoring, the beryllium control program also utilized surface contamination controls, building design, engineering controls, worker controls, material controls, and medical surveillance. The electronic database includes 367,757 area sampling records at 101 locations and 217,681 personal lapel sampling records collected from 194 employees over the period 1981-1997. Similar workplace samples were collected from 1961 to 1980, but they were not analyzed because they were not available electronically. Annual personal mean sampling concentrations for all workers ranged from 0.11 to 0.72 micrograms per cubic meter (microg/m3) with 95th percentiles ranging from 0.22 to 1.89 microg/m3; foundry workers worked in the highest concentration areas with a mean of 0.87 microg/m3 and a 95th percentile of 2.9 microg/m3. Area sampling concentrations, as expected, were lower than personal sampling concentrations. Mean annual area sample concentrations for all locations ranged from 0.02 to 0.32 microg/m3. The area sample 95th percentile concentrations for all years were below 0.5 microg/m3. For the overwhelming majority of samples, airborne beryllium concentrations were below the 2.0 microg/m3 standard. Although blood lymphocyte testing for beryllium sensitization has not been routinely conducted among these workers, this metal beryllium processing facility is the only large scale beryllium facility of its kind to have experienced only one unique a case of clinical chronic beryllium disease (CBD) ascertained by traditional medical monitoring procedures. The treating physician determined that this lung disease was likely caused by a systems reaction resulting from a mound contaminated with beryllium. However, he could not rule out the potential for inhalation exposure. Over the 17 years of measurement data analyzed, on occasion, airborne beryllium concentrations have exceeded 2.0 microg/m3; however, the Cardiff experience demonstrates that strict and consistent adherence to exposure control measures that emphasized airborne and surface levels and appropriate engineering controls, work practices, and use of personal protective equipment appears to have successfully prevented the incidence of clinical CBD with the exception of one unique case.

Identification of Selected Hormonally Active Agents and Animal Mammary Carcinogens in Commercial and Residential Air and Dust Samples

ABSTRACT In order to characterize typical indoor exposures to chemicals of interest for research on breast cancer and other hormonally mediated health outcomes, methods were developed to analyze air and dust for target compounds that have been identified as animal mammary carcinogens or hormonally active agents and that are used in commercial or consumer products or building materials. These methods were applied to a small number of residential and commercial environments to begin to characterize the extent of exposure to these classes of compounds. Phenolic compounds, including nonylphenol, octylphenol, bisphenol A, and the methoxychlor metabolite 2,2-bis (p-hydroxyphenyl)-1,1,1-trichloroethane (HPTE), were extracted, derivatized, and analyzed by gas chromatography/mass spectrometry (GC/MS)–selective ion monitoring (SIM). Selected phthalates, pesticides, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) were extracted and analyzed by GC/MS-SIM. Residential and workplace samples showed detectable levels of twelve pesticides in dust and seven in air samples. Phthalates were abundant in dust (0.3524 μg/g) and air (0.005-2.8 μg/m3). Nonylphenol and its mono- and di-ethoxylates were prevalent in dust (0.82-14 μg/g) along with estrogenic phenols such as bisphenol A and o-phenyl phenol. In this 7-sample pilot study, 33 of 86 target compounds were detected in dust, and 24 of 57 target compounds were detected in air. In a single sample from one home, 27 of the target compounds were detected in dust and 15 in air, providing an indication of chemical mixtures to which humans are typically exposed.

The Quartz Hazard: Effects of Surface and Matrix on Inflammogenic Activity

Modification of the quartz surface during the history of the particle is a powerful idea in understanding the variability of the quartz hazard. Interactions between quartz and other minerals are likely to occur in sediments, during industrial processing, or in matrix-bound quartz. We discuss new evidence regarding the basis of changes in the quartz surface that relate to changes in its ability to cause inflammation. Different samples of quartz were subjected to various biological assays. Endpoints included instillation of quartz into the tracheobronchial tree and measurement of PMN numbers in bronchoalveolar lavage (BAL) and in lung tissue, levels of the chemokine MIP-2 in BAL, and nuclear translocation of the transcription factor NF-kappaB in BAL cells. In vitro biological assays included cytotoxicity to epithelial cells, hemolytic activity, and radical activity of the particle surface as measured by electron spin resonance. Treatment of quartz with aluminium lactate impaired its ability to cause PMN recruitment, chemokine release, and NF-kappaB nuclear translocation in BAL. Workplace quartzes had no proinflammatory activity, which correlated with their ability to cause hemolysis but not their electron spin resonance (ESR) activity. Quartz in a matrix with coalmine dust or fly-ash showed different effects. In fly-ash, the toxicity was masked, but coalmine dusts were more toxic to epithelial cells than pure quartz in vitro; however, after instillation, the long-term inflammation was not related to the in vitro activity. Amelioration of quartz surface activity can occur in workplace samples of quartz and quartz samples whose surface is protected, to the extent that they have very little inflammogenic activity and display an inability to activate key subcellular pathways that lead to inflammation. Quartz from a workplace whose surface has been affected, or in a matrix such as coalmine dust or fly-ash, can have its toxicity modulated. These effects are due to minerals and organic compounds that can both decrease (e.g., aluminium salts) or enhance (e.g., coalmine dust matrix) biological activity and thus may contribute to toxicity in a complex way that is not easily predicted. Iron is a good example. There are reports that it can enhance quartz toxicity, or it may have little role to play in its toxicity, as shown here for almost pure quartz particles. A broad program of further research is needed before we have a sound understanding of the mechanisms of quartz toxicity.

Determination of airborne methyl isocyanate as dibutylamine or 1-(2-methoxyphenyl)piperazine derivatives by liquid and gas chromatography.

The usefulness of a glass fibre filter method to collect airborne methyl isocyanate (MIC) was studied in laboratory experiments and in a workplace during manufacture of mineral wool insulation material. Filter collection was based on derivatisation in situ with 1-(2-methoxyphenyl)piperazine (2MP). 2MP impinger sampling was also evaluated in the workplace. Impinger sampling with dibutylamine (DBA) was used as an independent method. The samples were analysed by liquid and gas chromatography using various detection techniques: mass spectrometry, ultraviolet and electrochemical detection (LC-MS, LC-UV, LC-EchD and GC-MS). The sampling efficiency of 2MP filters for MIC varied with the origin of the glass fibre filter. Two Whatman filters (diameter 25 mm) with altogether 21 mumol of 2MP collected 100% of 9.8 micrograms of MIC during 30 min at an airflow rate of 1 l min-1. The workplace measurements were performed at two concentration levels, 0.003 and 0.09 mg m-3. The theoretical amounts of derivatisation reagent were 42 mumol (2MP filter), 52 mumol (2MP impinger) and 100 mumol (DBA). MIC concentrations were 20% lower by the 2MP methods compared with the DBA method (statistically significant difference). Breakthrough was 6% for the DBA method and 9% for the 2MP impinger method. To trap both MIC and isocyanic acid, which was also present in the workplace samples, a tenfold molar amount of 2MP reagent was used. The precision of sample preparation, expressed as relative standard deviation, was 3.5% (0.17 microgram ml-1, n = 6). The precision of sampling in the workplace was 15% (0.002 mg m-3, n = 6). The limit of quantification was 0.0006 mg m-3 for 30 l of air by the 2MP impinger method and 0.03-0.05 mg m-3 by the 2MP filter method. Hence, airborne MIC can be determined using 2MP as derivatisation reagent. Impinger sampling is preferable when low concentration levels are expected.

Endotoxins and IgG antibodies as indicators of occupational exposure to the microbial contaminants of metal-working fluids.

The aim of this study was to evaluate workers' exposure to microbes and bacterial endotoxins during the use of metal-working fluids (MWF). Air and bulk sampling with biomonitoring of workers' serum IgG antibodies were used to estimate the exposure to biological agents at 18 workplaces. The types of emulsified MWF used were synthetic fluid, mineral oil or rape seed oil, in grinding, turning and drilling work. The endotoxin concentrations in the air ranged from 0.04 to 600 ng/m(3) when the endotoxin levels in MWF were 0.03-25,000 ng/ml. A high correlation was found between the endotoxin levels and the bacterial counts from MWF, as well as between the total culturable bacteria and the gram-negative bacteria concentrations in the air. Comamonas testosteroni and C. acidovorans were the most common strains in the samples but also colonies of Ochrobactrum anthropi, Pantoea agglomerans and Stenotrophomonas maltophilia were isolated from the workplaces. Fungi like Aspergillus, Cladosporium and Penicillium species were identified in the air but only rarely in the MWF. Positive IgG antibodies were found in the sera of 22 of the 25 MWF workers examined. Antibodies against S. maltophilia, P. agglomerans and C. acidovorans were the most common, appearing in 72%, 64% and 64%, respectively, of the cases. The MWF workers showed significantly higher IgG antibody responses to bacterial antigens than did the controls. The results clearly proved that in occupational hygiene measurements, endotoxins serve as excellent indicators of exposure to the microbial contaminants of MWF. IgG antibodies against antigens identified from workplace samples could be a practical tool for occupational health physicians.

Predictors of Influenza Vaccine Acceptance among Healthy Adults

Background. Previous studies investigating predictors of influenza vaccine acceptance have focused on high-risk patients or health care workers. Few studies have examined flu shot acceptance among healthy adults in workplace settings, even though influenza vaccine is recommended for this group as well.Methods. Two studies investigated predictors of flu vaccine acceptance in workplace samples of healthy adults. In the first study, 79 university employees were interviewed, while in the second, 435 corporate employees completed a questionnaire.Results. In the first study, flu shot acceptance was predicted by perceived effectiveness of the vaccine (r = 0.36), perceived likelihood of vaccine side effects (r = −0.32), and having received the shot in the previous year (r = 0.25). In the second study, flu shot acceptance was again predicted by perceived effectiveness (r = 0.49), likelihood of side effects (r = −0.31), and previous flu shot (r = 0.66) and was also related to older age (r = 0.10) and to predicted percentage of co-workers who also received the shot (r = 0.24).Conclusions. The current studies indicate that predictors of vaccine acceptance among healthy adults are similar to those identified in studies of high-risk patient populations and health care workers.

Determination of hexavalent chromium in industrial hygiene samples using ultrasonic extraction and flow injection analysis.

A simple, fast, and sensitive method was developed for the determination of hexavalent chromium (CrVI) in workplace samples. Ultrasonic extraction in alkaline solutions with 0.05 M (NH4)2SO4-0.05 M NH3 provided good extraction efficiency of CrVI from the sample and allowed the retention of CrVI on an ion-exchange resin (95%). The CrVI in the sample solution was then separated as an anion from trivalent chromium [CrIII] and other cations by elution from the anion-exchange resin with 0.5 M (NH4)2SO4 in 0.1 M NH3 (pH 8) buffer solution. The eluate was then acidified with hydrochloric acid and complexed with 1,5-diphenylcarbazide reagent prior to flow injection analysis. By analyzing samples with and without oxidation of CrIII to CrVI using CeIV, the method can measure CrVI and total Cr. For optimizing the separation and determination procedure, preliminary trials conducted with two certified reference materials (CRMs 013-050 and NIST 1633a) and three spiked samples (ammonia buffer solution, cellulose ester filters and acid washed sand) indicated that the recovery of CrVI was quantitative (> 90%) with this method. The limit of detection for FIA-UV/VIS determination of the Cr-diphenylcarbazone complex was in the sub-nanogram range (0.11 ng). The technique was also applied successfully to a workplace coal fly ash sample that was collected from a power plant and paint chips that were collected from a heating gas pipe and a university building. The principal advantages of this method are its simplicity, sensitivity, speed and potential portability for field analysis.