• Title/Summary/Keyword: Mass Median Diameter(MMD)

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Seasonal Variation of Size Distributions of Polycyclic Aromatic Hydrocarbons in Air Particulates (대기 부유분진중 다환방향족 탄화수오류의 계절적 입경농도 분포 변이)

  • Chung, Yong;Park, Seong-Eun;Hwang, Man-Sik
    • Journal of Korean Society for Atmospheric Environment
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    • v.14 no.6
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    • pp.577-588
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    • 1998
  • Polycyclic aromatic hydrocarbons (PAHs) are products of incomplete combustion and, in urban area atmosphere, are mainly traffic or heating in origin. Size-segregated aerosol samples were collected on the Eixth story of Shinchon on the Yonsei campus, using a high-volume cascade impactor, between August 1994 and September 1995. Ten PAHs were analyzed by GC/MSD. The size distribution of PAH-containing particulates followed approximately a log-normal relationship with the majority of PAH content associated with particles below 3.0mm. PAHs concentration in submicron particles increased during the winter months. The Mass Median Diameter (MMD) value of annual particulates in the heavy traffic area of Shinchon shows about 1.6 pm. The MMD values of air particulate in winter were the lowest values and similar to that in summer, while MMD values of seasonal PAHs were generally lower than 1.0 pm. Among the PAHs, MMD values of PAHs with the more than 5 benzen ring were averagely lower than those with 4 benzin rings. Especially MMD's of dibenzo (a, h) anthracene in winter was clearly lower than in summer. This reason may be caused by fuels used for heating. In this area, 50∼80% PAHs mass was particles smaller than 1.0mm aerodynamic diameter in size range, and the MMD values of PAHs lower than those of other country's area.

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Particle Size of Aerosol from 0.25% Cadmium Chloride Nebulizing Solution for Inhalation Toxicology Study (흡입독성 연구에 이용될 0.25% 염화카드뮴 네뷸라이징 용액 에어로졸의 입경)

  • Jeung Jae Yeal;Lee Ki Nam
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.5
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    • pp.1257-1263
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    • 2003
  • The modified engineering methodology and the modified electronic circuit in classical ultrasonic principles were applied to ultrasonic aerosol nebulizer for inhalation toxicology study of cadmium aerosol. 1532.96ppm Cd nebulizing solution was used to generate cadmium aerosol for particle size analysis with the modifying source and inlet temperatures. The results of particle size analysis for cadmium aerosol were as following. The highest particle counting for source temperature 20℃ was 399.75 × 10² in inlet temperature 100℃ and particle diameter 0.75㎛. The highest particle counting for source temperature 50℃ was 399.70 × 10² in inlet temperature 50℃ and particle diameter 0.75㎛. The highest particle counting for source temperature 70℃ was 411.14 × 10² in inlet temperature 100℃ and particle diameter 0.75㎛. The ranges of geometric mean diameter were 0.74-0.79㎛ in source temperature 20℃, 0.65-0.72㎛ in source temperature 50℃, and 0.65-0.80㎛ in source temperature 70℃. The smallest geometric mean diameter was 0.65㎛ in source temperature 50, 70℃ and inlet temperature 20, 50℃, and the largest geometric mean diameter was 0.80㎛ in source temperature 70℃ and inlet temperature 100℃. The ranges of geometric standard deviation were 1.71-1.80 in source temperature 20℃, 1.27-1.61 in source temperature 50℃, and 1.27-2.29 in source temperature 70℃. The lowest geometric standard deviation was 1.27 in source temperature 50, 70℃ and inlet temperature 20, 50℃, and the highest geometric standard deviation was 2.29 in source temperature 70℃ and inlet temperature 100℃. Generated aerosol for cadmium inhalation toxicology study was polydisperse aerosol with the above geometric standard deviation 1.2. The ranges of mass median diameter(MMD) were 1.75-2.25㎛ in source temperature 20℃, 1.27-1.61㎛ in source temperature 50℃, and 1.27-2.29㎛ in source temperature 70℃. The smallest MMD was 1.27㎛ in source temperature 50, 70℃ and inlet temperature 20, 50℃, and the largest MMD was 2.29㎛ in source temperature 70℃ and inlet temperature 100℃. Cadmium chloride concentration in nebulizing solution affected the particle size and distribution of cadium aerosol in air. MMO for inhalation toxicology testing in OECD and EU is less than 3㎛ and EPA guidance is less than 4㎛. In our results, in source temperatures of 20, 50, 70℃, and inlet temperatures of 20, 50, 100, 150, 200, 250℃ were conformed to the those guidance.

Trace Metals Characterization of Respirable Dust during Yellow Sand Phenomena in Seoul Area (서울지역의 황사발생시 호흡성 분진 중 미량원소의 특성 평가)

  • 신은상;선우영
    • Journal of environmental and Sanitary engineering
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    • v.17 no.1
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    • pp.41-51
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    • 2002
  • This research was carried out using Anderson air sampler which were set up on the roof of the Engineering College of Konkuk University at Hwayang-Dong, Kwangjin-Gu, Seoul from Aug. 1992 to foul. 1999. The results are as follows: The major component of yellow sand is soil particles based upon the observation that particles ranging from $3.3~7.0{\mu}m$ occupy 36~63%. It is certain that the increase of fine particles of respirable dust during yellow sand phenomenon in Seoul area affects the human body. The trace metals from natural sources like Al, Ca, Fe, K, Na, and Si show larger mass median diameter(MMD) values during yellow sand phenomenon than in normal situations while the values of MMD for Mn and Pb rarely changes. Noticeably, the changes in value of MMD of water soluble elements like ${NO_3}^{-}$ and ${SO_4}^{2}$ are 2.3 and 6.6 times higher during the yellow sand phenomenon compared to normal situations, respectively. This fact is regarded as decisive evidence showing that ${NO_3}^{-}$ and ${SO_4}^{2}$ in the air are attached to yellow sand and move together.

Particle Size Analysis of Cadmium Aerosol for Cadmium Inhalation Toxicology Study (766ppm Cadmium Nebulizing Solution) (카드뮴의 흡입독성 연구를 위해 설계된 에어로졸 발생장치에서 발생된 카드뮴 에어로졸의 입경분석(766ppm 카드뮴 네뷸라이징 용액))

  • Jeung Jae Yeal;Milton Donald K.;Kim Tae Hyeung;Lee Jong Young;Jahng Doo Sub;Kang Sung He;Song Young Sun;Lee Ki Nam
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.5
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    • pp.1035-1041
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    • 2002
  • Ultrasonic nebulizer with the application of new engineering methodology and the design of electronic circuit and 766ppm Cd nebulizing solution were used to generate cadmium aerosol for inhalation toxicology study. The results of particle size analysis for cadmium aerosol were as following. The highest particle counting for source temperature 20℃ was 43.449 x 10³ in inlet temperature 250℃ and particle diameter 0.75㎛. The highest particle counting for source temperature 50℃ was 43.211 x 10³ in inlet temperature 100 ℃ and particle diameter 0.75㎛. The highest particle counting for source temperature 70℃ was 41.917x10³ in inlet temperature 250℃ and particle diameter 0.75㎛. The ranges of geometric mean diameter(GMD) were 0.677-1.009㎛ in source temperature 20℃, 0.716-0.963㎛ in source temperature 50℃, and 0.724-0.957㎛ in source temperature 70℃. The smallest GMD was 0.677㎛ in source temperature 20℃ and inlet temperature 20℃. and the largest GMD was 1.009㎛ in source temperature 20℃ and inlet temperature 20℃. The ranges of geometric standard deviation(GSD) were 1.635-2.101 in source temperature 20℃. 1.676-2.073 in source temperature 50℃, and 1.687-2.051 in source temperature 70℃. The lowest GSD was 1.635 in source temperature 20℃ and inlet temperature 20℃, and the highest GSD was 2.101 in source temperature 20℃ and inlet temperature 200℃. Aerosol generated for cadmium inhalation toxicology study was polydisperse aerosol. The ranges of mass median diameter(MMD) were 1.399-5.270㎛ in source temperature 20℃. 1.593-4.742㎛ in source temperature 50℃, and 1.644-4.504㎛ in source temperature 70℃. The smallest MMD was 1.399㎛ in source temperature 20℃ and inlet temperature 20℃, and the largest MMD was 5.270㎛ in source temperature 20℃ and inlet temperature 200℃. Increasing trends for GMD, GSD, and MMD were observed with same source temperature and increase of inlet temperature. MMD for inhalation toxicology testing in EPA guidance is less than 4㎛. In our results. inlet temperature 20 and 50℃ in source temperature 20℃, and inlet temperature 20 to 150℃ in source temperature 50 and 70℃ were conformed to the EPA guidance. MMD for inhalation toxicology testing in OECD and EU is less than 3㎛. In our results, inlet temperature 20 and 50℃ in source temperature 20, 50, and 70℃ were conformed to the OECD and EU guidance.

Particle Size Analysis of Lead Aerosol with the use of 2730ppm Lead Nebulizing Solution for Inhalation Toxicology Study (흡입독성 연구를 위한 2730ppm 납 네뷸라이징 용액에서 발생된 에어로졸의 입경분석)

  • Jeung Jae Yeal;Kang Sung Ho;Kim Sam Tae;Lee Eun Kyoung;Song Young Sun;Lee Ki Nam
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.2
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    • pp.518-524
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    • 2003
  • Ultrasonic nebulizer with the application of new engineering methodology and the design of electronic circuit was made for lead inhalation toxicology study and 2730ppm lead nebulizing solution was used to generate lead aerosol. After modification of source and inlet temperatures, the results of particle size analysis for lead aerosol were as following. The highest particle counting for source temperature 20℃ was 39933.66 in inlet temperature 100℃ and particle diameter 0.75tLm. The highest particle counting for source temperature 50℃ was 39992.71 in inlet temperature 250℃ and particle diameter 0.75μm. The highest particle counting for source temperature 70℃ was 37569.55 in inlet temperature 50℃ and particle diameter 0.75μm. The ranges of geometric mean diameter(GMD) were 0.754-0.784μm for source temperature 2℃, 0.758-0.852μm for source temperature 50℃, and 0.869-1.060μm for source temperature 70℃. The smallest GMD was 0.754μm in source temperature 20℃ and inlet temperature 20℃, and the largest GMD was 1.060μm in source temperature 70℃ and inlet temperature 250℃. The ranges of geometric standard deviation(GSD) were 1.730-1.782 for source temperature 20℃, 1.734-1.894 for source temperature 50℃, and 1.921-2.148 for source temperature 70℃. The lowest GSD was 1.730 in source temperature 20℃ and inlet temperature 20℃, and the highest GSD was 2.148 in source temperature 70℃ and inlet temperature 250℃. Lead aerosol generated in this study was polydisperse. The ranges of mass median diameter(MMD) were 1.856-2.133μm for source temperature 20℃, 1.877-2.894μm for source temperature 50℃, and 3.120-6.109μm for source temperature 70℃. The smallest MMD was 1.856μm in source temperature 20℃ and inlet temperature 20℃, and the largest MMD was 6.109μm in source temperature 70℃ and inlet temperature 250℃. Slight increases for GMD, GSD, and MMD values were observed with same source temperature and increase of inlet temperature. MMD for inhalation toxicology testing in EPA guidance is less than 4μm. In this study, source temperature 20℃ and 50℃ with inlet temperature from 20℃ to 250℃ were conformed to the EPA guidance, but inlet temperature 20℃ and 50℃ for source temperature 70℃ were conformed EPA guidance. MMD for inhalation toxicology testing in OECD and EU is less than 3μm. In this study, source temperature 20℃ and 50℃ with inlet temperature from 20℃ to 250℃ were conformed to the EPA guidance, but none for source temperature 70℃.

Characteristics of Black Carbon Particles in Ambient Air Using a Single Particle Soot Photometer (SP2) in May 2013, Jeju, Korea (SP2 (Single Particle Soot Photometer)를 이용한 제주도 5월 Black Carbon 특성)

  • Oh, Jun;Park, Jinsoo;Lee, Sanguk;Ahn, Joonyoung;Choi, Jinsoo;Lee, Sangdeok;Lee, Yonghwan;Kim, Hyunjae;Hong, Youdeog;Hong, Jihyung;Kim, Jeongho;Kim, SangWoo;Lee, Gang-Woong
    • Journal of Korean Society for Atmospheric Environment
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    • v.31 no.3
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    • pp.255-268
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    • 2015
  • Single particle soot photometer (SP2) is an advanced instrument capable of real-time measurement of concentration, coating thickness, and size distribution of individual BC particle using laser-induced incandescence. So far, there have been insufficient studies examining the real-time characteristics of BC in Korea. In this study, we examined temporal variations in BC concentration and mass size distribution of BC in volume equivalence diameter at a background site of Aewol, Jeju in May. Average concentration and mass median diameter (MMD) of BC particles measured during the study period (06~ 16 May 2013) were $0.69{\pm}0.48{\mu}g/m^3$ and $196{\pm}17nm$, respectively. The BC concentration measured in Aewol was very similar to that observed in the spring of 2012 in Baengnyeong island, and showed diurnal profiles similar to those in other background areas. MMD of BC ranged from 172 to 222 nm. It was found that the mass size distribution of BC varied depending on the location (ground-based), season, types of air masses, and altitude (aircraft-based).

A Characteristic Analysis of Physical, Chemical and Electrical Property for Bunker C Fly Ash (Bunkder C유 회분의 물리적, 화학적, 전기적 특성분석)

  • 이재근;이정언;안영철
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1996.04a
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    • pp.88-96
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    • 1996
  • The characteristic analysis of fly ash generated from a fired power plant using bunker-C oil has been investigated. Ash size distribution by an optical microscopy with image processing technique, morphological shape by a scanning electron microscope(SEM) and microscope, chemical composition by the inductively coupled plasma emission spectrometry(ICP), and resistivity measurement as a function of temperature and moisture content by the resistivity meter are performed. A study of physical, chemical and electrical characteristics of bunker-C fly ash plays an important role of improving the performance of an electrostatic precipitator and protecting air pollution. The samples of bunker-C fly ash for analysis were collected from the electrostatic precipitator hopper of Ulsan Power Plant Unit 1 and Pusan Power Plant Unit 1. Mass median diameter(MMD) of bunker-C fly ash was measured 12.7${\mu}{\textrm}{m}$, while MMD of fly ash generated from the mixture of bunker-C oil(40%) and domestic anthracitic coal(60%) was 25.7${\mu}{\textrm}{m}$. The morphological structure of bunker-C fly ash consisted of fine particles of non-spherical shape. The primary chemical components of bunker-C fly ash were composed of SiO2(2.36%), Al2O3(4.91%), Fe2O3(14.33%) and C(11.84%). Resistivity of bunker-C fly ash was found to be increased with increasing temperature at the range of 100~15$0^{\circ}C$ and was measured 103~104 ohm-cm.

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Effects of Extract of Radix Achyranthis Bidentatae on Cadmium Inhalation Toxicity in Rats (우슬 추출물이 카드뮴 흡입폭로된 흰쥐의 독성해독에 미치는 영향)

  • Kim Hong Ki;Jeung Jaeyeal;Park Seung Jong;Kang Sung Ho;Song Young Sun;Lee Ki-Nam
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.2
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    • pp.474-483
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    • 2004
  • To know the effects between Cd inhalation toxicity and extract of Radix Achyranthis Bidentatae, 4 rat groups were exposed to Cd aerosol in air using whole-body inhalation exposure for 6 hours/day, 5 days/week, and 4 weeks. Cd concentration in air was 1.03㎎/㎥ and mass median diameter(MMD) was 1.69㎛. 3 different dose intraperitoneal injections of extract of Radix Achyranthis Bidentatae to 3 inhalation exposure groups was done for 4 weeks and the results were as follows: The highest body weight gain for 4 weeks and food intake per day were from inhalation exposure group I and the highest lung and liver weight were also from inhalation exposure group I. The highest kidney weight was from inhalation exposure group III. The lowest Cd content in lung was 33.49㎍/g from inhalation exposure group I. The lowest Cd concentration in blood was 9.36㎍/㎗ from inhalation exposure control. Cd concentrations of 40.02㎍/g in liver and 69.18㎍/g in kidney were the lowest from inhalation exposure group I and III, respectively. The lowest Cd concentration in liver was 21.08㎍/g from inhalation exposure group III and The lowest Cd concentration in kidney was 15.78㎍/g from inhalation exposure group II. For weekly Cd concentration in urine, the value of the fourth week from inhalation exposure group III was the highest. For weekly Cd concentration in feces, the value of the first week from inhalation exposure group III was the highest. The highest metallothionein concentration in lung was 53.42 ㎍/g from inhalation exposure group III and the highest metallothionein concentration in liver was 188.18㎍/g from inhalation exposure group III. The highest metallothionein concentration in kidney was 143.92㎍/g from inhalation exposure group III. The highest Hct, Hb, and WBC values were from inhalation exposure group II and the highest RBC value was from inhalation exposure group III.

Effects of Ethyl Acetate Extracts of Folium Mori on Cadmium Inhalation Toxicity (상엽 Ethyl Acetate 추출물이 카드뮴의 흡입독성에 미치는 영향)

  • Jeung Jaeyeal;Song Young Sun;Lee Ki Nam
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.3
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    • pp.700-710
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    • 2003
  • For the experiment of the effects between cadmium aerosol inhalation toxicity and ethyl acetate extracts of Folium Mori, 4 inhalation exposure groups of rat were exposed to cadmium aerosol in air by whole-body inhalation exposure for 6 hours/day, 5 days/week, and 4 weeks. Cadmium concentration in the air was 0.96㎎/㎥ and mass median diameter (MMD) was 2.48㎛ with 1.85 of geometric standard deviation(GSD). Intraperitoneal injections of ethyl acetate extracts of Folium Mori to inhalation exposure groups were performed for 4 weeks and the results were as follows: The highest body weight gain for 4 weeks and food intake per day were 159.29/4 weeks in treated group III and 18.45g/day in treated group I, respectively. The highest lung and liver weights were 1.31 g in treated group I and 9.42g in treated group III, respectively. The highest kidney weight was 2.21g from treated group I. The lowest cadmium content in lung was 86.39㎍/g from treated group III and the lowest cadmium concentration in blood was 2.72㎍/㎗ from treated group II. Cadmium concentrations of 22.09㎍/g in liver and 24.82㎍/g in kidney were the lowest from inhalation exposure group I and III, respectively. For weekly cadmium concentration in urine, the value of the fourth week from treated group III was the highest, 1.35㎍/㎖. For weekly cadmium concentration in feces, the values of the second and fourth week from treated group I were the highest, 1.11㎍/g. The highest metallothionein concentration in lung was 31.85㎍/g from treated group III and the highest metallothionein concentration in liver was 205.77㎍/g from treated group III. The highest metallothionein concentration in kidney was 206.55㎍/g from treated group III. The highest Hct and Hb values were 38.26% and 11.63g/㎗ from treated group III, respectively. The highest RBC and WBC values were 7.68×106/㎣ and 9.85×10³/㎣ from treated group I, respectively.

A Study on the Characteristic of Airborne Lead Particle Size by Industry (업종별 공기중 납입자의 입경별 분포특성에 관한 조사 연구)

  • Park, Dong Wook;Paik, Nam Won
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.5 no.2
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    • pp.160-171
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    • 1995
  • The size characteristics of lead particle which is one of the important factors associated with absorption of lead were ignored in establishing lead standard. This study was conducted to investigate distribution of lead particles by operation of industry. Aerodynamic Mass Median Diameters (MMD) of airborne lead particles in the battery and litharge manufacturing industry were $14.1{\mu}m$ and $15.1{\mu}m$, respectively. There was no significant difference between those two values(p>0.05). However, the diameters in radiator manufacturing and secondary smelting industry were $1.3{\mu}m$, $4.9{\mu}m$, respectively. Those were significantly smaller than the particle sizes in other industries(p<0.05). Total lead concentrations in the secondary smelting industry were higher than those in the battery and litharge manufacturing industry. Total lead concentrations in other industries except radiator manufacturing industry exceeded the standard of $50{\mu}g/m^3$. Only radiator manufacturing industry indicated lead concentrations significantly lower than those in other industries(p<0.05). Concentrations of lead particles smaller than $1{\mu}m$ defined as respirable fraction by OSHA's CPA model assumption were $72.4{\mu}g/m^3$ in the secondary smelting industry, exceeding $50{\mu}g/m^3$. The relationship of concentrations between total lead and lead of particles smaller than $1{\mu}m$ was log Y = 0.46 logX + 0.06(n=119, $r^2=0.44$, p=0.0001). Relationship of respirable lead concentrations between OSHA and ACGIH was significantly detected in the litharge and battery manufacturing industry(p=0.0001), but was not significant in the radiator(p=0.2720) and secondary smelting manufacturing industry(p=0.2394). As MMDs of lead particles generated in industry were small, difference of respirable lead concentration between OSHA and ACGIH became smaller. There was a significant difference between concentrations respirable lead defined by two organizations such as OSHA and ACGIH in the battery and litharge manufacturing industry. Average concentration of respirable lead by ACGIH definition was 43.3 % of total lead in secondary smelting and 48.9 % in radiator manufacturing industry, and lower fractions were indicated in battery and litharge manufacturing industry. Relationships of total lead with IPM, TPM, and RPM were significant respectively(p=0.0001) and lead concentrations by particle size could be estimated using this relationship. Linear regression equation between total lead concentration(X) and ACGIH-RPM concentration(Y) was log Y = 0.76 log X - 0.40($r^2=0.89$, p=0.0001).

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