• Journal of Environmental Health Sciences
• /
• v.46 no.1
• /
• pp.78-87
• /
• 2020

Objectives: To identify the degree of physical burden, a determination was undertaken of dust collection efficiency, inhalation pressure, and CO₂ concentration related to health masks certified by the Ministry of Food and Drug Safety (MFDS). Methods: Twenty health masks were purchased on the market. Dust collection efficiency and inhalation pressure were determined in the same manner as in MFDS certification testing, respectively using TSI Model 8130 (TSI, U.S.) and ART Plus (Korea). CO₂ concentrations for 20 subjects using a CO₂ analyzer (G100, G150, Geotechnical Instrument Ltd., UK) were measured with a similar method as a total inward leakage test. In addition to CO₂ levels, dead space volumes in the masks was determined for predicting concentrations of CO₂ in inhalation air. Results: Most of the dust collection efficiencies found for the 20 masks were far higher than the standard. Four KF94s met KF99 and four KF80s even met KF94. Most inhalation pressures were also much lower than the standard, with many almost one-half of the standard. The mean and standard deviation of CO₂ concentration in the mask were 2.9±0.44%. Considering dead volume, the prediction for CO₂ concentration in the inhalation air was 4,395±1,266 ppm. Conclusions: For healthy men and women, the dust collection efficiency and inhalation pressure of health masks were not at a level that would affect their health. Although CO₂ levels in the inhalation air were predicted not to affect health, research on the physiological effects of health masks on Koreans is needed for more precise research.

• Toxicological Research
• /
• v.26 no.3
• /
• pp.203-208
• /
• 2010

Bronchoalveolar lavage (BAL) is a useful tool in researches and in clinical medicine of lung diseases because the BAL fluid contains biochemical and cytological indicators of the cellular response to infection, drugs, or toxicants. However, the variability among laboratories regarding the technique and the processing of the BAL material limits clinical research. The aim of this study was to determine the suction frequency and lavage fraction number necessary to reduce the variability in lavage using male Sprague-Dawley rats. We compared the total cell number and protein level of each lavage fraction and concluded that more cells and protein can be obtained by repetitive lavage with a suction frequency of 2 or 3 than by lavage with a single suction. On the basis of total cell recovery, approximately 70% of cells were obtained from fractions 1~3. The first lavage fraction should be used for evaluation of protein concentration because fractions 2~5 of lavage fluid were diluted in manifolds. These observations were confirmed in bleomycin-induced inflamed lungs of rats. We further compared the BAL data from the whole lobes with data from the right lobes and concluded that BAL data of the right lobes represented data of the whole lobes. However, this conclusion can only be applied to general lung diseases. At the end, this study provides an insight into the technical or analytical problems of lavage study in vivo.

• Toxicological Research
• /
• v.33 no.2
• /
• pp.165-171
• /
• 2017

Bisphenol A (BPA) is a monomer used in a polymerization reaction in the production of polycarbonate plastics. It has been used in many consumer products, including plastics, polyvinyl chloride, food packaging, dental sealants, and thermal receipts. However, there is little information available on the inhalation toxicity of BPA. Therefore, the aim of this study was to determine its inhalation toxicity and effects on the estrous cycle, spatial learning, and memory. Sprague-Dawley rats were exposed to 0, 10, 30, and $90mg/m^3$ BPA, 6 hr/day, 5 days/week for 8 weeks via whole-body inhalation. Mortality, clinical signs, body weight, hematology, serum chemistry, estrous cycle parameters, performance in the Morris water maze test, and organ weights, as well as gross and histopathological findings, were compared between the control and BPA exposure groups. Statistically significant changes were observed in serum chemistry and organ weights upon exposure to BPA. However, there was no BPA-related toxic effect on the body weight, food consumption, hematology, serum chemistry, organ weights, estrous cycle, performance in the Morris water maze test, or gross or histopathological lesions in any male or female rats in the BPA exposure groups. In conclusion, the results of this study suggested that the no observable adverse effect level (NOAEL) for BPA in rats is above $90mg/m^3$/6 hr/day, 5 days/week upon 8-week exposure. Furthermore, BPA did not affect the estrous cycle, spatial learning, or memory in rats.

• Toxicological Research
• /
• v.28 no.4
• /
• pp.217-224
• /
• 2012

In recent decades, titanium dioxide ($TiO_2$) nanoparticles have been used in various applications, including paints, coatings, and food. However, data are lacking on the toxicological aspects associated with their use. The aim of this study was to assess the inhalation toxicity of $TiO_2$ nanoparticles in rats by using inhalation exposure. Male Wistar rats were exposed to $TiO_2$ nanoparticles for 2 weeks (6 hr/day, 5 days/week) at a mean mass concentration of $11.39{\pm}0.31mg/m^3$. We performed time-course necropsies at 1, 7, and 15 days after exposure. Lung inflammation and injury were assessed on the basis of the total and individual cell counts in bronchoalveolar lavage fluid (BALF), and by biochemical assays, including an assay for lactate dehydrogenase (LDH). Furthermore, histopathological examination was performed to investigate the lungs and nasal cavity of rats. There were no statistically significant changes in the number of BALF cells, results of biochemical assays of BALF and serum, and results of cytokine analysis. However, we did observe histopathological changes in the nasal cavity tissue. Lesions were observed at post-exposure days 1 and 7, which resolved at post-exposure day 15. We also calculated the actual amounts of $TiO_2$ nanoparticles inhaled by the rats. The results showed that the degree of toxicity induced by $TiO_2$ nanoparticles correlated with the delivered quantities. In particular, exposure to small particles with a size of approximately 20 nm resulted in toxicity, even if the total particle number was relatively low.

• Analytical Science and Technology
• /
• v.34 no.2
• /
• pp.87-98
• /
• 2021

In this study, we developed the nanoparticle multi-generator by 3D printer fusion deposition modeling (FDM) method that can reliably generate and deliver nanoparticles at a constant concentration for inhalation risk assessment. A white ABS filament was used as the test material, and SMPS was used for concentration analysis such as particle size and particle distribution. In the case of particle size, the particle size was divided by 100 nm or less and 100 to 1,000 nm, and the number of particles concentration, mass concentration, median diameter of particles, geometric average particle diameter, etc were measured. The occurrence conditions were the extruder temperature, the extruding speed of the nozzle, and the air flow rate, and experiments were conducted according to the change of conditions including the manufacturer's standard conditions. In addition, the utility of inhalation risk assessment was reviewed through a stability maintenance experiment for 6 h. As a result of the experiment, the size of the nanoparticles increased as the discharger temperature increased, as the discharge speed of the nozzle increased, and as the air flow rate decreased. Also, a constant pattern was shown according to the conditions. Even when particles were generated for a long time (6 h), the concentration was kept constant without significant deviation. The distribution of the particles was approximately 80 % for particles of 60 nm to 260 nm, 1.7 % for 1 ㎛ or larger, 0.908 mg/㎥ for the mass concentration, 111 nm for MMAD and 2.10 for GSD. Most of the ABS particles were circular with a size of less than 10 nm, and these circular particles were aggregated to form a cluster of grape with a size of several tens to several hundred nm.

• Toxicological Research
• /
• v.24 no.2
• /
• pp.119-127
• /
• 2008

The objectives of this study were to examine the lung injury and inflammation caused by manual metal arc stainless steel(MMA-SS) welding fume inhalation and to evaluate the recovery process. Sprague-Dawley rats were exposed to MMA-SS welding fumes for 2 h per day in a whole-body exposure chamber, with a total suspended particulate(TSP) concentration of $51.4{\pm}2.8mg/m^3$(low dose) or $84.6{\pm}2.9mg/m^3$(high dose) for 30 days. The animals were sacrificed after 30 days of exposure as well as after a 30-day recovery period. To assess the inflammatory or injury responses, cellular and biochemical parameters as well as cytokines were assayed in the bronchoalveolar lavage fluid(BALF). MMA-SS welding fume exposure led to a significant elevation in the number of alveolar macrophages(AM) and polymorphonuclear cells(PMN). Additionary, the values of $\beta$-n-acetyl glucosaminidase($\beta$-NAG) and lactate dehydrogenase(LDH) in the BALF were increased in the exposed group when compared to controls. After 30 days of recovery from exposure, a significant reduction in inflammatory parameters of BALF was observed between the exposed and recovered groups. Slight, but significant elevations were noted in the number of AM and PMN in the recovered groups, and AM that had been ingested fume particles still remain in the lungs. In conclusion, these results indicated that welding fumes induced inflammatory responses and cytotoxicity in the lungs of exposed rats. Fume particles were not fully cleared from lungs even after a 30-day recovery period.

• Journal of Environmental Health Sciences
• /
• v.30 no.4
• /
• pp.301-307
• /
• 2004

1,3-butadiene(DB) is a well-established rodent carcinogen, and a probable carcinogen to humans. This study was investigated the formation of hemoglobin adduct in ICR female mice inhaled with BD for 3 weeks (5 hr/day, 5 days/week). Body weights of mice were significantly low from onward day 4 or 9 of exposure comparing the control. Hemoglobin adducts formed by DB exposure were (N-2-hydroxy-3-butenyl) valine (HB Val adduct) and (N-2,3,4-trihydroxy-butyl)valine(THB Val adduct). The levels of HB Val adducts were 1.8, 3.7 and 6.2 pmol/mg globin for the 500 ppm BD inhalation group, and 5.7, 7.4 and 16.0 pmol/mg globin for the 1000 ppm BD inhalation group, when observed on the $1^{st},\;2^{nd},\;and\;3^{rd}$ week after inhalation exposure, respectively. The levels of THBVal adducts were 32.0, 42.0 and 55.0 pmol/mg globin for the 500 ppm DB inhalation group, and 67.8, 72.7 and 83.5 pmol/mg globin for the 1000 ppm BD inhalation group, when observed on the $1^{st},\;2^{nd},\;and\;3^{rd}$ week after inhalation exposure, respectively. Ratios of THBVal and HBVal adducts were higher at earlier exposure period and lower concentration. Ratios on the $1^{st},\;2^{nd},\;and\;3^{rd}$ week were 17.8, 11.4 and 8.87 for the 500 ppm BD inhalation group, and 11.9, 9.8 and 5.2 for the 1000 ppm BD inhalation group, respectively. In conclusion, THB Val and HB Val adducts were the important hemoglobin adducts in ICR female mice inhaled with BD, and the latter was more appropriate biomarker than the other for biological monitoring of BD exposure.

• Toxicological Research
• /
• v.26 no.3
• /
• pp.217-222
• /
• 2010

Many studies have reported that bleomycin, anti-cancer drug, induces pulmonary fibrosis as a side effect. However, few investigations have focused on the dose-response effects of bleomycin on pulmonary fibrosis. Therefore, in the present study, we investigated the effects of different doses of bleomycin in male mice. ICR mice were given 3 consecutive doses of bleomycin: 1, 2, or 4 mg/kg in bleomycin-treated (BT) groups and saline only in vehicle control (VC) groups. The animals were sacrificed at 7 and 24 days postinstillation. The severity of pulmonary fibrosis was evaluated according to inflammatory cell count and lactate dehydrogenase (LDH) activity in the broncho alveolar lavage fluid (BALF), and lung tissues were histologically evaluated after hematoxylin and eosin (H&E), and Masson's trichrome staining. BT groups exhibited changed cellular profiles in BAL fluid compared to the VC group, which had an increased number of total cells, neutrophils, and lymphocytes and a modest increase in the number of macrophages at 7 days post-bleomycin instillation. Moreover, BT groups showed a dose-dependent increase in LDH levels and inflammatory cell counts. However, at 24 days after treatment, collagen deposition, interstitial thickening, and granulomatous lesions were observed in the alveolar spaces in addition to a decrease in inflammatory cells. These results indicate that pulmonary fibrosis induced by 4 mg/kg bleomycin was more severe than that induced by 1 or 2 mg/kg. These data will be utilized in experimental animal models and as basic data to evaluate therapeutic candidates through non-invasive monitoring using the pulmonary fibrosis mouse model established in this study.

• Korean Journal of Adult Nursing
• /
• v.21 no.4
• /
• pp.379-390
• /
• 2009

Purpose: The study was done to investigate the effect of ethanol inhalation on postoperative nausea in patients using Patient Controlled Analgesia (PCA). Methods: The data were collected from June 1st 2006 to September 30th, 2007. The subjects were 70 patients who had had orthopedic surgery under general anesthesia. The levels of the Visual Analogue Scale (VAS) was used to measure postoperative nausea. The experimental group was given ethanol inhalation using ethanol pads and the control group received normal saline pads. All participants were instructed to take two deep sniffs with the pad one inch from the nose. This was repeated every five minutes for three doses. The collected data were analyzed using SPSS/WIN 12.0 program. Results: The study supported all hypotheses. "The experimental group given first dose of ethanol inhalation would have a lower level postoperative nausea compared to the control group"(t = -5.900, p = .000). "The experimental group given second doses of ethanol inhalation would have a lower level postoperative nausea compared to the control group"(t = -7.507, p = .000). "The experimental group given third doses of ethanol inhalation would have a lower level postoperative nausea compared to the control group"(t = -6.685, p = .000). Conclusion: According to these results, the ethanol inhalation can be considered an effective nursing intervention for relieving the postoperative nausea in patients using PCA.

• Journal of Haehwa Medicine
• /
• v.26 no.1
• /
• pp.49-57
• /
• 2017

Objectives : The purpose of this study was to investigate the efficacy of inhalation therapy using Zizyphus jujuba var. spinosa blended oil and spa therapy on stress in adults. Methods : The study design was a double blind, randomized, single center clinical trial. A total of 30 volunteers who were highly stressed and were over 9 points on POMS(profile of mood states) participated in this study. Inhalation therapy using Zizyphus jujuba var. spinosa blended oil and spa therapy were applicate for the experimental group and Jojoba oil inhalation and spa therapy was given for the control group. During the 2 weeks, the participants were treated about inhalation and spa therapy twice a week. The treatment sequence is spa therapy after inhalation therapy. Result : The improvement of stress was evaluated by POMS, HRV(Heart Rate Variability), EEG(Electroencephalography), PSQI(Pittsburgh Sleep Quality Index), salivary cortisol. After treatment, POMS was significantly decreased between the experimental group and the control group. In other measurement(HRV, EEG, PSQI, salivary cortisol) except POMS, there were not significant. Overall, however, they showed a tendency to alleviate stress in the experimental group. Conclusions : We suggest that inhalation therapy using Zizyphus jujuba var. spinosa blended oil and spa therapy might be effective on stress.