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Methods to study occupational exposures to fungi and fungal materials in facilities where the dominant exposure is the pathogenic and allergenic fungus Aspergillus fumigatus are lacking. Air samples were collected near a conveyor in a wood chip recycling plant to compare methods that might be used to assess exposure to A. fumigatus or suitable proxies. These included total dust mass, total intact spores, culturable propagules growing > 35 degrees C, ergosterol, A. fumigatus allergen Asp f1, and quantitative polymerase chain reaction for A. fumigatus. Of these measurements, Asp f1 showed the most promise based on its relative response to measurements where there is a long history of use in industrial hygiene practice (total mass, ergosterol, total intact spores, culturable propagules).

Simultaneous analysis of common antineoplastic agents potentially hazardous to healthcare workers is of much interest for the evaluation of the overall health risk to these workers. Such analysis could be applied to both air and surface monitoring samples to provide a broader indication of risk to combinations of these agents. It was determined that the ability to simultaneously evaluate five frequently used, potentially hazardous agents was sufficient for general evaluation of exposures to healthcare workers. The approach used to select the five agents was to obtain a list of the agents used most frequently in both a cancer hospital and an outpatient cancer treatment center, then review the list to determine which agents were potentially more hazardous to human health. From these reviews, it was decided to attempt to develop an analytical method able to detect and quantify the presence of 5-fluorouracil, ifosfamide, cyclophosphamide, doxorubicin HCl, and paclitaxel. A reverse-phase high performance liquid chromatograph (HPLC) with a Waters Symmetry C8 column and a UV wavelength of 195 nm was selected for method development. The mobile phase was 22.75 percent acetonitrile in water buffered to a pH of 6.0. The HPLC analytical method developed is able to detect all five agents of interest, and at minimum detectable concentrations of 0.5-microgram/mL for each of the five agents.

Cyclophosphamide is a known human carcinogen. In July 1999, in a report at a conference on cytotoxic drugs in Sweden, it was indicated that cyclophosphamide (CP) was not effectively controlled by high efficiency particulate air (HEPA) filters.((1)) This then raised a concern that the existing air monitoring methods, which utilize polytetrafluoroethylene (a.k.a. PTFE, or Teflon) or glass fiber filters for evaluation of antineoplastics such as CP in air may also be ineffective for collection and quantification of such agents. It was decided that further evaluation of the existing filter method for monitoring antineoplastics in air be conducted. This evaluation determined that the filter method of monitoring was minimally effective for some antineoplastic agents, and that an alternate method of monitoring should be sought. The method subsequently developed utilizes a solid sorbent tube, Anasorb 708, a methacrylic acid polymer. Evaluation of this sorbent tube for adsorption and desorption properties found it had a greater than 90 percent recovery for both CP and ifosfamide. Other agents evaluated included 5-fluorouracil, doxorubicin, and paclitaxel. All three agents were able to be detected and measured by use of Anasorb 708 solid sorbent tube. Validation of the method was then conducted with air pulled through the tubes via attachment to an air manifold system at air flows ranging from 1.5 to approximately 4.0 liters per minute for up to 24 hours. This evaluation did validate the Anasorb 708 tube as an effective media for collection of airborne concentrations of CP from less than 1 microgram up to approximately 2 mg (2000 microgram) per tube. This corresponds to a concentration range of approximately 0.7 microgram/m(3) (0.0007 mg/m(3)) to 0.7 mg/m(3) in a 5.76 m(3) volume of air. This method can provide accurate information on airborne concentrations of CP for purposes of conducting risk assessments or evaluation of risk management methods.

A polymerase chain reaction assay was optimized to detect P. carinii cysts in composite dust samples. The optimal assay was capable of detecting as few as 10(3) P. carinii cysts in 50 mg of dust. Two dust collection devices were evaluated for efficiency and precision of collection of bulk dust and compatibility with the optimized PCR protocol for P. carinii DNA detection. A handheld vacuum cleaner equipped with a high-retention bag was found to be superior to a 37-mm filter cassette attached to an electrically powered vacuum pump in terms of dust collection efficiency (87% [n = 37] versus 81% [n = 35]), although the precision of the two devices as assessed by the standard deviation was similar (6.2% versus 6.3%). However, the vacuum cleaner method was not as compatible with the PCR-based detection assay as the filter cassette method. The filter cassette appears to be a better device for use in conjunction with PCR-based detection of P. carinii DNA in bulk dust samples from both smooth and carpeted surfaces.

A method of evaluating surface contamination caused by selected antineoplastic agents was studied. The antineoplastic agents tested were cyclophosphamide, ifosfamide, doxorubicin hydrochloride, fluorouracil, and paclitaxel. Each agent was reconstituted and prepared as a stock solution. A 0.1-mL portion of each solution was spread evenly over a 600-cm2 area of a stainless steel surface, a resin countertop surface, and a vinyl flooring surface. After drying, the surfaces were wiped with each of two types of commercially available wiping materials (What-man no. 42 filters and Kimberly-Clark Kimwipes). A blend of methanol, acetonitrile, and buffered water was used both as the wetting agent for wiping the surfaces and as a desorbing solution. The desorbate was analyzed for drug concentration by reverse-phase high-performance liquid chromatography (HPLC). Mean +/- S.D. percent total recovery ranged from 72.4% +/- 17.6% to 95.3% +/- 2.9% for the vinyl surface wiped with filters, 91.5% +/- 5.4% to 104.7% +/- 0.8% for the resin surface wiped with filters, 73.9% +/- 2.3% to 95.3% +/- 1.7% for the stainless steel surface wiped with filters, and 18.2% +/- 1.4% to 372.8% +/- 8.0% for the stainless steel surface wiped with Kimwipes. Results were best for ifosfamide and cyclophosphamide. Kimwipes were deemed ineffective for this monitoring method because an ingredient interfered with the quantitative analytical tests. A wipe-sampling, desorption, and HPLC method for monitoring surface contamination by selected antineoplastic agents was sufficiently accurate and sensitive to evaluate surfaces typically found in both the pharmacy and drug administration areas of oncology treatment facilities.

Pneumocystis carinii pneumonia (PCP) remains the most common opportunistic infection among human immunodeficiency virus-infected persons. Despite this, little is known concerning the transmission dynamics of this infection. In the absence of a reliable method to isolate and culture P. carinii from environmental samples, it has not been possible to assess the importance of person-to-person transmission in the epidemiology of PCP. A molecular viability assay was developed for the human form of P. carinii (P. carinii f sp hominis) that is applicable to both clinical specimens and environmental samples. This assay will enable the evaluation of the spread and persistence of viable human P. carinii in the environment.

PCR detection methods are useful in studies of organisms not amenable to culture. Inhibitors in environmental samples can interfere with such assays. We describe a magnetic bead DNA capture protocol that removes inhibitors from outdoor air samples, maintaining the sensitivity of a 16S Pneumocystis carinii mitochondrial rRNA gene-based PCR.

This article presents discussion of the assessment of the exposure of children to fungi, substances derived from fungi, and the environmental conditions that may lead to exposure. The principles driving investigations of fungal contamination and subsequent exposure are presented as well as guidelines for conducting these investigations. A comprehensive description of available research sampling and analysis techniques is also presented.

An inexpensive test chamber has been constructed that provides an environment appropriate for testing the effects of temperature and chemical interactions on gaseous emissions from test solutions. Temperature, relative humidity, and ventilation rate can be controlled and a well-mixed atmosphere can be maintained. The system is relatively simple and relies on heated tap water or ice to adjust the temperature. Temperatures ranging from 9 to 21 degrees C have been maintained. At an average temperature of 15.1 degrees C, temperatures at any location within the chamber vary by no more than 0.5 degree C, and the temperature of the test solution within the chamber varies by no more than 0.1 degree C. The temperatures within the chamber are stable enough to generate precise steady-state concentrations. The wind velocities within the chamber are reproducible from run to run. Consequently, the effect of velocity on the rate of evaporation of a test chemical is expected to be uniform from run to run. Steady-state concentrations can be attained in less than 1 hour at an air exchange rate of about 5 per hour.

This paper describes the development and evaluation of an inhalable bioaerosol manifold sampler for the collection of replicate samples over sequential sampling periods. Wind tunnel experiments at wind velocities < or = 0.6 m/sec (< or = approximately 120 ft/min) and at a sampling velocity of 0.6 m/sec yielded sampling efficiencies within 10% of the American Conference of Governmental Industrial Hygienists' inhalable curve up to particle diameters of about 18 microns and efficiencies within 18% for diameters up to 26 microns. At wind velocities > or = 0.6 m/sec, a sampling velocity of 0.8 m/sec yielded efficiencies that were within 15% of the inhalable curve up to diameters of about 22 microns and within 20% for diameters up to 25 microns. Microscopic counts of 15.6-micron and 25.6-micron monodisperse polystyrene beads aerosolized in the wind tunnel and collected with the manifold sampler yielded precise concentrations (pooled CV = 9.0 and 5.3%, respectively) averaging 115% and 92%, respectively, of measurements with the APS Model 3310 aerodynamic particle sizer. Field tests in a cotton dust environment demonstrated the ability to generate a time/concentration profile of fungal spores similar to that indicated for cotton dust levels determined with horizontal elutriators. Cotton dust was sampled efficiently while cotton fibers were excluded. Field tests on a dairy farm indicated no statistically significant bias (p = 0.72) between spore concentrations determined with the manifold sampler and concentrations determined through a central test port.

A solid sorbent sampling tube packed with Tenax-GC is used with a personal sampling pump to collect samples of white (yellow) phosphorus vapor from air. The phosphorus is leached from the exposed sorbent into xylene and quantitated by gas chromatographic analysis. The capacity of the sorbents is in the range 10 to 20 microgramP4per100 mg of sorbent, which allows for up to 4 hrs of sampling at the OSHA Standard, 0.1 mg/m3. No interferences from red phosphorus, phosphine, water vapor, or other common gases are significant. The effects on the method of variations in temperature, pressure, humidity, sample storage and shipping conditions, and chromatographic parameters were determined.

A personal sampling and analytical method has been developed for the determination of monochloroacetic acid (MCA) vapor in air. The sampling procedure is the collection of MCA with a solid sorbent sampling tube packed with silica gel. The MCA is leached from the exposed sorbent into distilled, deionized water and quantitated by ion chromatographic analysis. The method has been validated in the concentration range of 0.35 to 29 mg/m3 in 3-L air samples. The capacity of the silica gel is in the range of 3 to 4 mg of MCA per 100 mg of sorbent, which allows for up to 8 hr of sampling at concentrations greater than 40 mg/m3. There are no significant interferences from glycolic acid, acetic acid, dichloroacetic acid, trichloroacetic acid, fluoride and chloride compounds, or water vapor. The effects on the analytical data due to variations in the temperature and humidity of the test atmosphere, sample storage time and chromatographic parameters have been found to be minimal.