The hypothesis was that multiple layers of disposable nitrile gloves would provide more protection against cyclohexanol than a single layer relative to Standardized Breakthrough Time (SBT) and Steady State Permeation Rate (SSPR). The aims of this research were (1) to determine if a disposable nitrile glove resisted cyclohexanol, and (2) to determine if multiple glove layers provided more protection. In this study, cyclohexanol was used because of its high boiling point and solubility in water to enable closed-loop permeation cell water collection. Lavender Nitrile Powder-Free Exam Gloves were used because they are the least expensive and thinnest disposable nitrile gloves from Kimberly-Clark. The American Society for Testing and Materials (ASTM) Method F739-12 for permeation resistance under continuous contact was used in this study through single, double and triple layers of Lavender disposable nitrile glove pieces. Samples were taken from the collection side of the permeation cells and later analyzed by gas chromatography-mass spectrometry. The Standardized Breakthrough Times (SBTs) of single, double and triple layers samples were 0.25 � 0.25 minutes, 45 �15 minutes, and 180 � 60 minutes, respectively, which were Not Recommended, Good and Excellent according to Kimberly Clark safety rating. The SSPR of single layer samples was 363.3 � 4.0 �g/cm2/min, which rating was Poor according to Kimberly-Clark safety rating and Fair according to Ansell safety rating. The diffusion coefficient was 257 � 29 *10-8 cm2/min. Double and triple layers samples never reached SSPR during the 8-hour tests. The results proved that multiple layers did provide more protection against cyclohexanol, where double layers were 180 times more protective than single layer, and triple layers were 720 times more protective than a single layer relative to standardized breakthrough time. The limitations of this study were: (1) glove pieces swelled, so that the calculation for diffusion coefficients may not be valid; (2) the duration between each sample was not short enough to have accurate average permeation rate at the times less than 10 minutes and greater than 60 minutes; (3) the shaking water bath could not simulate exactly hand motions; (4) this study did not test other Kimberly Clark disposable nitrile gloves, such as Blue and Purple.

Mixtures are widely used in both industry and home. Nearly all the technical grade feedstocks of industry are mixtures. Previous studies have indicated that some chemicals in mixtures can permeate through glove materials faster than expected from the pure solvent alone. The hypothesis was that some chemicals in the mixtures will permeate through the disposable nitrile glove faster in the presence of other chemicals. The aims of the present research were (1) to determine if a specific disposable nitrile glove was resistant to chemicals in a mixture, and (2) to determine which chemicals permeated fastest. In the present research, the mixture of 2-butoxyethanol (2-BE; 29.0%), monoethanolamine (MEA; 9.0%), polyethylene glycol nonylphenyl ether (PGNE; 2.9%) and water (59.1%) simulating a common floor stripper used in the workplace was investigated to determine if disposable Lavender nitrile powder-free exam gloves from Kimberly-Clark were resistant. The American Society for Testing and Materials Method F739-12(1) for permeation resistance under continuous contact was used, with samples taken at specific times from the collection side of the permeation cell for later analysis by gas chromatography-mass spectrometry. The standardized breakthrough times (SBTs) of 2-BE in the mixture were 0-5 minutes for 2-BE and 5-10 minutes for MEA, compared with 5-10 minutes for 2-BE in water and 10-20 minutes for MEA in water. The steady-state permeation rates (SSPRs) of 2-BE and MEA in the mixture were 85�13 and 35�21 g/cm2/min, respectively. The SSPR of 2-BE in water was 269�23 g/cm2/min and the SSPR of MEA in water was 37.5�3.4 g/cm2/min. Chemicals in mixtures did permeate through glove materials faster than expected in the solvent alone. The Lavender disposable nitrile glove is not recommended to resist this mixture by Kimberly-Clark criteria. Some of the limitations in this study were: (1) PGNE is a polymer and could not be detected by GC-MS, so it is difficult to evaluate the effect of PGNE on permeation. (2) The commercial mixture could not be purchased in a small amount. (3) Hand motions could not be taken into account.

The purpose of this project was determining the exposure of toxic vapors, particularly benzene, toluene, ethylbenzene and xylene (BTEX), to workers during an underground storage tanks (UST) inspection process. BTEX are a group of hydrocarbons that are commonly found as volatile organic compounds (VOCs) in gasoline products. Thousands of other VOCs can also be found in gasoline, some that have been identified and others that have not. For this project, a total of 8 different fillingstations were examined during a UST inspection with the help of a local regulatory agency. The project was conducted during the months of January to April 2017. The exposure assessment was divided into 4 phases(laboratory pre-calibrations, preliminary, secondary and personal sampling) to assess whether high air concentrations of VOCs and BTEX were present at the sites. A Photoionization Detector (ppbRAE 7240) was used to measure total VOC levels. A portable Gas Chromatography (GC) (PetroPRO) was used to measure the levels of BTEX. Integrated personal breathing zone sampling was also done at four sites with time ranges of 60-99 minutes. Personal samples were analyzed by GCMS after desorption of the charcoal tube with carbon disulfide.

VOC levels were at much higher concentrations when compared to the BTEX levels at concentrations ranging from 1.0ppm to 200ppm. BTEX concentrations levels decreased over time at constant cool temperatures and ranged from 118 to 340, 151 to 483, 276 to 926, and 249 to 869 ppb for BTEX, respectively. It was also observed that with higher increasing ambient temperatures, concentrations increased over time from 111 to 769, 81 to 504, 75 to 503, and 68 to 406ppb for BTEX, respectively. BTEX concentrations were overall below OSHA’s PELs and STELs, and NIOSH STELs. For one particular site, concentrations of benzene did exceed NIOSH RELs of 0.1 ppm (100ppb) and was above OSHA’s Action Level (AL) at 0.5 ppm (500ppb).

Overall, BTEX concentrations decreased over time with cooler temperatures and increased with warmer temperatures. VOCs were significantly high based on location and concentrations levels changed based on the time of the day related to temperatures. Turbine sumps showed the highest concentrations for VOCs and BTEX when compared to fillings sumps and dispenser sumps. Personal samples results were basically inconclusive because the samples were not analyzed until 6 months after sampling. Also, exposure assessment was not done for a total 8-hour exposure as required to compare with Cal/OSHA regulations and NIOSH guidelines. Similar concentrations were found for benzene and xylene (benzene being the highest concentration and xylenes being the lowest) as Site 4. All data were lower than 0.1 Cal/OSHA PELs, with the highest concentrations being 40.8 ppb for Site 5 and the lowest at 0.5 ppb for Site 6.In general, exposure levels to BTEX were not of immediate concern but it is still recommended for workers to take preventative measures to reduce exposures.

There are numerous factors that make ELF-EMF exposure assessment complex and difficult. A substantial amount of research has been published on the relationship between ELF-EMF and adult cancers, but the overall evidence of ELF-EMF health risks remains contradictory or inconclusive. Currently, there are no mandated standards for ELF-EMF exposure in the US, only recommended exposure limits at very high levels as ceiling values. The current exposure assessment methods do not measure all the characteristics needed to act as surrogates for possible adverse health effects suggestive of needs for better exposure assessments and for the development of standardized ELF-EMF measurement protocols. While the research continues on health effects and better exposure assessment design and metric for exposure assessments, concerned individuals, especially workers and employers who work directly with high intensity ELF-EMF sources, can use appropriate combinations of controls to limit exposure.

Human exposure to organic gunshot residues is a largely under researched topic in environmental and occupational health. This study aimed to examine how the components of a complex liquid blend affect the permeation behavior of its constituents. In the initial study, Hoppes No. 9 Gun Bore Cleaner, a firearm cleaning solvent, was chosen to test two types of disposable nitrile gloves from Kimberly-Clark’s Kimtech Science: the thinnest (Lavender) and thickest (Blue). Testing was conducted using the 1-inch diameter closed-loop ASTM F739 cell at 35℃ without recirculation with n-decane collection, and subsequent analysis via capillary gas chromatography-mass spectrometry to quantify the permeated compounds. Results showed that the thicker Blue glove resisted Hoppe’s permeation more than the thinner Lavender glove. The Lavender glove permeated 3.2 times more mass at 60 minutes despite having the same standardized breakthrough times (7.5 ± 2.5 min). Unexpectedly, the kerosene fraction permeated at a much higher rate than anticipated, appearing at the standardized breakthrough time for Hoppe’s, contrary to the Kimberly-Clark chemical resistance guide's listing for Sterling disposable nitrile glove material. Notably, components reported by the glove manufacturer to quickly permeate nitrile material, like ethanol, did not permeate slower than expected, hinting at a possible carrier function. A semiquantitative risk assessment confirmed the inadequacy of both gloves, suggesting that individuals using personal protective equipment may not receive the anticipated resistance to chemical permeation when dealing with complex mixtures, thus heightening exposure risk. Further research is necessary to develop improved glove testing measures to ensure worker safety and health.Additionally, this research examined how methyl centralite and ethyl centralite, two major gunshot residue components, simulated gunshot residues when permeating disposable nitrile glove material in three different solvents: Hoppe’s Gun Cleaning Solvent, n-decane, and an n-decane/ethanol 7:3 v/v mixture. The objective was to determine whether ethanol plays a key role in a carrier effect. Permeation testing followed a modified ASTM F739-20 standard method at 35.0 ± 0.1 ℃ with sample quantification conducted via GC-MS analysis. The findings indicate significant variations in permeation behavior across solvents. Hoppe’s solvent caused a type D permeation behavior characterized by a notable increase in permeation rate to a maximum post-standardized breakthrough time then followed by a lower SSPR. This was attributed to ethanol and other polar components. Conversely, the n-decane/ethanol mixture displayed a type A behavior with the SSPR being the maximum permeation rate, with markedly reduced permeation rates and total permeated analyte mass, indicating ethanol's likely pivotal role in the carrier effect. The study results emphasize the importance of considering the complete chemical composition of mixtures when assessing their interactions with protective equipment, and are suggestive of the need for comprehensive testing protocols in PPE selection. Limitations include the lack of prior research on firearm cleaning solvents' permeation through PPE and challenges in comparing study findings with manufacturer-reported glove effectiveness for individual components. The study suggests adjusting concentrations of analytes and solvent groups for future investigations. Overall, this research offers insights into the permeation behavior of complex chemical mixtures through disposable nitrile gloves, aiding in better protective equipment selection and testing methodologies, and thereby improving worker safety and health. Finally, this research examines how different glove materials affect the permeation of gunshot residue components compared to when these materials are used individually. Simulated gunshot residues containing methyl centralite and ethyl centralite dissolved in a 7:3 v/v mixture of n-decane and ethanol, mimicking gun cleaning solvent, were used to challenge two types of disposable glove materials: nitrile rubber and polyvinylchloride (PVC). Testing was again conducted using the closed-loop ASTM F739 cell without recirculation and n-decane collection at 35.0 ± 0.1 oC, followed by quantification of permeated compounds through capillary gas chromatography-mass spectrometry. Results showed that the combination of nitrile gloves alone exhibited the highest reduction in permeation. The next best reduction was observed with a combination of nitrile and vinyl gloves, with the vinyl side specifically facing the challenge solution. However, for Hoppe’s solvent, the kerosene components appeared at the standardized breakthrough time. Moreover, using vinyl-only glove material led to increased permeation of ethyl centralite compared to methyl centralite, while all other material combinations resulted in decreased permeation of ethyl centralite compared to methyl centralite. This suggests that the specific combination or orientation of glove materials used affected the expected resistance to chemical permeation and needs to be confirmed with different challenge chemicals and glove material combinations. Further research is necessary to develop improved glove testing measures to ensure worker safety and health, particularly when utilizing gloves with multiple types of materials such as laminated gloves.

This research was conducted to determine whether permeation of gloves on a robotic moving hand would produce shorter normalized breakthrough times (tb) and faster steady state permeation rates (Ps) compared with a non-moving hand and the American Society of Testing and Materials (ASTM) F739-96 closed loop method. Cyclohexanol was used to complete this research because of its high boiling point and previous open loop data were available from glove manufacturers. A method was first developed to detect imperfections in glove material. Four glove products were selected for testing from one manufacturer. The ASTM closed loop method was used to generate new data for cyclohexanol. A dynamic whole glove permeation method was developed using a robotic hand, a water circulation system, and a sampling point to allow for interval sampling. This method was used to test still and moving hand configurations, and GC-MS analysis was used to analyze for cyclohexanol. The closed loop data for the Safeskin, Kimtech Science Blue, Purple, and Sterling nitrile gloves had tb of 29±2, 26±1, 18±1, and 8±1 minutes, respectively. Open loop data for the Sterling glove had a tb of 112 minutes. The respective Ps for the same gloves were 2.2±0.6, 12±1, 12±2, and 21±1 ìg/cm2/min. Compared to the ASTM closed loop method, whole glove permeation (still hand) for the Safeskin gloves produced a shorter tb (20±3 minutes). The Safeskin gloves also produced a higher Ps (10.0±0.7 ìg/cm2/min). The most protective gloves for the whole glove still hand were the Blue nitrile gloves with a tb of 22±5 minutes and Ps of 9±1 ìg/cm2/min. For moving hand whole glove experiments, the Safeskin and Blue nitrile gloves produced shorter tb (14±4 and 18±5 minutes, respectively) compared to the ASTM closed loop method. For Ps the Safeskin and Sterling gloves were higher (11.8±0.7 and 29±3, respectively). Results for tb and Ps were not consistent between the different types of gloves. The Safeskin and Kimtech Science Blue gloves were the best performing gloves overall. It is not recommended to wear the Sterling gloves when working with cyclohexanol.

Acetoin, diacetyl, and 2,3-pentanedione are artificial butter flavoring ingredients. Occupational exposures to diacetyl are associated with severe respiratory disease including bronchiolitis obliterans. Dynamic and passive air sampling and analytical methods were developed for simultaneous sampling of these ketones using 10 % (w/w) O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) on Tenax TA (80/100 mesh). PFBHA O-oximes of the ketones were synthesized with above 95 % purity for standards. Ketone vapors of known concentrations and relative humidities (RHs) were generated in Tedlar gas bags for dynamic sampling. A syringe pump delivered ketones in aqueous solution to an air dilution system and an exposure chamber for passive sampling. The dynamic sampling tubes contained 200 mg of coated solid sorbent in a Pyrex tube. The passive samplers were obtained by compressing 300 mg of coated solid sorbent into a pellet of 30 mm diameter and 0.53 mm thickness. The ketone vapors permeated a silicone membrane and crossed a path length of 3.2 mm to the pellet surface. After sampling, the coated solid sorbent was suspended in water, ultrasonicated, microwaved, extracted with hexane, and centrifuged. An aliquot of the hexane extract was analyzed by capillary gas chromatography-mass spectrometry using selective ion monitoring with the internal standard method. For dynamic sampling, acetoin, diacetyl, and 2,3-pentanedione vapor sampling efficiencies were 90.2 ± 6.9, 92.2 ± 5.9, and 82.5 ± 4.4 % respectively at 5-20 ppb when sampled at 100 mL/min for 8 hours at 25 °C for both 5 and 80 % RHs. Recoveries between 75-125 % were also obtained at 40 ºC at both RHs. For passive sampling, experimental sampling constants for acetoin, diacetyl, and 2,3-pentanedione at 25 ºC for both 5 and 80 % RHs were 59.4 ± 8.5, 55.3 ± 7.6, and 50.0 ± 6.3 mL/min respectively. The experimental sampling constants at 40 ºC were statistically lower at 5 % RH, but had no statistical difference at 80 % RH compared to at 25 ºC. Overall, quantitative, selective, and sensitive dynamic and passive sampling methods were developed around the 2012 ACGIH TLV (10 ppb) for diacetyl in the presence of similar concentrations of acetoin and 2,3-pentanedione.