Determination of urinary mandelic and phenylglyoxylic acids in ethylbenzene -exposed paint manufacturing workers in 2019

MINIST RY OF EDUCATION AND TRAINING MINISTRY OF HEALTH DANG THI TRANG DETERMINATION OF URINARY MANDELIC AND PHENYLGLYOXYLIC ACIDS IN ETHYLBENZENE-EXPOSED PAINT MANUFACTURING WORKERS IN 2019 Major : Preventive Medicine Doctor Code : D720302 THESIS OF GRADUATION MEDICAL DOCTOR COURSE 2015-2021 Supervisor Assoc Prof Khuong Van Duy PhD MD Vti Xuan Trung Hanoi “2021 r-u -ÍM Qỉ ugc V Hl ACKNOWLEDGMENT I would like to offer my thanks to the Boards of Hanoi Medical Universit}’ Institute of Preventive Medicine and Public Health, as well as the teachers of the Department of Occupational Health for supporting me to this thesis in the most convenient conditions I would like to express mv great appreciation to all the individuals and teams below, that without them I would not be able to accomplish my dissertation Firstly I would like to express my deepest gratitude to my supervisor A/Prof Khuong Van Duy for his patient guidance, enthusiastic encouragement and useful critiques of this research work His willingness to give his time so generously has always been very much appreciated Not only did I leant a lot from his academic knowledge, but also his enthusiasm and professional attitude towards work inspired me to pursue my career I would like to offer mv special thanks to PhD MD Vu Xuan Trung subject "Determination urinary Mandelic and Phenylglyoxylic acids in ethylbenzene-exposed paint manufacturing workers and associated factors 2019"- Code: 218/07/TLĐ for creating conditions for me to use data to write this thesis Last but not least would like to give thanks to my family and close friends, for their support and encouragement throughout my study Hanoi May 2021 Dang Thi Trang r-u -ÍM Qỉ ugc V Hl COMMITMENT Respectfully addressed to: - Board of Hanoi Medical University - Board of Institute for Preventive Medicine and Public Health - Department of Population - Board of Dissertation Assessment My name is Dang Thi Trang - Student of Hanoi Medical University, course 2015 - 2021 majoring in Preventive Medicine Doctor, hereby declare that: This is a research that I participated under the scientific guidance of Assoc.Prof Khuong Van Duy and PhD MD Vu Xuan Trung Tile research content and research results in this tope are truthful This study is part of the project ’’.Nghiên cứu xác định mức (lộ thầm thấu cua Ethylbenzene thõng qua sán phẩm chuyên hóa acid mandelic (MA) acid phenylglyoxylic (PGA) nước tiếu người lao dộng có tỉcp xúc"- Code: 218 07TI.Đ by PhD MD Vu Xuan Trung, who is Director of the Center for Occupational Health is the project manager in 2019 Tire author lias allowed me to participate in the process of data processing, analysis and use of this data for my graduation thesis In addition the thesis also uses a number of comments, assessments as well as data from other authors, agencies and organizations, all with source annotations clearly stated in the references If I find any fraud I take full responsibility for the content of my thesis The author of the thesis Dang Till Trang TABLE OF CONTENTS r-u -ÍM CỊỈ ugc V Hl INTRODUCTION CHAPTER 1: LITERATURE REMEW 1.1 Concepts and definitions 1.1.1 Employee 1.1.2 Occupational disease 1.1.3 Volatile organic compounds (VOC) 1.2 Characteristics of ethylbenzene 1.2.1 Chemical and physical data, production and usage status 1.2.2 Exposure, penetration, metabolism, and excretion .4 1.2.3 The effect of ethylbenzene 1.3 Research on exposure and biological monitoring of ethylbenzene exposed9 1.4 Associated factors impact on the level of the urinary Mandelic and Phenylglyoxylic acids in ethylbenzene-exposed paint manufacture worker's 12 1.4.1 Associated factors among the concentration of urinary MA PGA 12 1.4.2 High performance liquid cliromatographic (HPLC) for Determination of Urinary Metabolites of Ethylbenzene .13 1.5 Paint industry in Vietnam .13 1.6 Paint companies in Hung Yen and Hanoi .14 CHAPTER 2: METHODS 16 2.1 Study subjects 16 2.1.1 Study subjects 16 2.1.2 Inclusion criteria 16 2.1.3 Exclusion criteria 16 2.2 Location and time of study 16 2.2.1 Research location .16 r-u -ÍM Qỉ ugc V Hl 2.2.2 Research tune 2.3 Research Methods 16 16 2.3.1 Study design 16 2.3.2 Sample size and samplingmethod 17 2.2.3 Research variables andindicators .17 2.3.4 Instruments 19 2.3.5 Data collection 19 2.3.6 Sample analysis at the laboratory 20 2.3.7 Evaluation criteria 22 2.3.8 Data analysis , 23 2.3.9 Bias and bias control .23 2.3.10 Ethical consideration .24 CHAPTER 3: RESULTS 25 3.1 Characteristics of participants 25 3.2 Ethylbenzene and Styrene concentration in the working environment 27 3.3 The level of urinaiv MA and PGA in ethylbenzene-exposed paint manufacturing workers 32 CHAPTER4: DISCUSSION 38 4.1 Characteristics of participants 38 4.2 Ethylbenzene and Styrene in the working environment 38 4.3 The level of ethylbenzene contamination through MA and PGA metabolism products in urine 41 4.4 Limitation of the study 45 CONCLUSION 46 RECON BIENDATIONS 47 REFERENCES APPENDIX Ss KJ;- r-u -ÍM CỊỈ ugc V Hl ABBREVIATIONS The American Conference of Governmental Industrial ACGIH Hygienist Benzene, toluene, ethylbenzene, xylene BTEX Benzene, toluene, xvlene BTX Central nervous system CNS Ethylbenzene EB Ethylbenzene and styrene EBS Environmental protection agency EPA High performance liquid chromatographic HPLC International Agency for Research on Cancer I ARC Mandelic Acid MA National Institute for Occupational Safety and Health MOSH Occupational Safety and Health Administration OSHA Phenylglyoxylic Acid PGA Volatile organic compounds VOCs Chromatography Mass Spectometry GC'MS Creatinin Cre International Agency for Research on Cancer IARC r-u -ÍM «£ ugc V Hl LIST OF TABLES Table 2.1: Variables and research indicators 17 Table 2.2: Process and equipment used in the laboratory 20 Table 2.3: Acceptable concentrations of ethylbenzene and styrene in the working environment 22 Table 3.1: Demographic characteristics of participants 25 Table 3.2: Characteristic of participants in the working process .26 Table 3.3: Lifestyle habits of participants .26 Table 3.4: Distribution of ethylbenzene and styrene samples exceeded the permissible limit in the working environment 27 Table 3.5: The average concentration of Ethylbenzene and Styrene in the working environment 28 Table 3.6: Individual Ethylbenzene and Styrene samples that exceeded the permissible limit 29 Table 3.7: Individual ethylbenzene and styrene concentration (8 hour's) .30 Table 8: Urinary MA and PGA acids concentration 32 Table 9: Total urinary concentration of MA andPGA .32 Table 3.10: Total concentration of MA- PGA by age 33 Table 3.11: Totalconcentration of MA-!- PGA by working period .34 Table 3.12: Totalconcentration of MA— PGA by working position 35 Table 3.13: Totalconcentration of MA- PGA by paint companies 36 LIST OF FIGURES Figure 1.1: Ethylbenzene metabolism in the human body Figure 2.1: The process of sampling and analysing ethylbenzene and styrene in the workers’ ambient air 19 Figure 3.1: Total concentration of MA and PGA in participants .33 Figure 3.2: Correlation between ethylbenzene concentration and the total concentration of MA and PGA in the urine 37 ABTRACTS Background: Currently many countries have used the ethylbenzene metabolic products in urine is MA and PGA as biological monitoring index for ethylbenzene-exposed workers There is no biological monitoring for ethylbenzene in Vietnam The research aimed to: Determine ethylbenzene and styrene concentrations in tile working environment through environmental monitoring and individual dose monitoring, and Determine the level of urinary MA and PGA in ethylbenzene-exposed paint manufacturing workers in 2019 Methods: A cross sectional study was conducted in Painting Company from January' 2019 to April 2021 SPSS and Minitab software described frequency tables; Pearson's correlation evaluated the correlation of ethylbenzene concentration in the working environment with ethylbenzene's metabolite in urine Results: The average ethylbenzene and styrene concentrations in the working environment was 49.58 ± 34.67mg/m5 and 1.13 ± 0.97 mg/nf respectively (within the permissible limit) The individual ethylbenzene concentration (8 hours) in the Mixing group was 99.77 ± 62.72 mg-’nf and in the Quality' Control and Packing group was 19.58 ± 17.07 nig/m The average concentration of urinary MA and PGA were 77.21 ± 75.lSmg/g creatinine and 46.58 ± 51.76mg/g creatinine, respectively The total average concentration of MA + PGA was 123.08- 101.83mg'g creatinine Correlation coefficient between ethylbenzene concentration and the total concentration of MA and PGA in the urine was 0.82 Conclusion: The maximum concentration of ethylbenzene and sty rene at research facilities was within the permissible limit The average total concentration of MA and PGA in tile three companies were within the permissible limit according to ACGIH There is a strong correlation between ethylbenzene exposure and tile metabolite in tile urinaiy(MA and PGA) (r = 0.82) Key words: MA PGA Ethylbezene Ethylbenzene-exposed Styrene -ÍM Qỉ ugc V Hl INTRODUCTION Every day approximately 6.400 people die from occupational accidents or diseases'- Almost million deatlis are due to fatal work-related diseases every year Furthermore, work-related diseases represent the main cause of death at work, killing almost six times more workers than occupational accidents It is estimated that 2.7% of the disease burden worldwide can be attributed to quantified occupational risks2 In 2019 the proportion of the population aged 15 and over participating in the work was estimated to be 61% After the home environment, the workplace is where employees spend most of the time During that time, workers may be exposed to many health risk factors The harmful chemical substances are ubiquitous in manufacturing, construction, and service-sector workplaces4 Die volume of chemicals in commerce increased a great deal during the 20* centuiy especially synthetic organic chemicals5 Due to their toxicity and carcinogenic potential, volatile organic compounds (VOCs) cause hazardous effects on human health Among the monoaromatic volatile organic compounds, benzene and its derivatives are highlighted Ethylbenzene (EB) is representative species of benzene homologue, which is recognized as an occupational pathogen in Vietnam and many countries6 According to The National Institute for Occupational Safety and Health (NIOSH) of the American and the Occupational Safety and Health Administration (OSHA) Ethylbenzene is potential for widespread human exposure because of structural similarity to benzene and toluene It lias been classified as possibly carcinogenic to humans (Group 2B) by the International Agency for Research on Cancer (IARC) S Occupational workers exposed to a mixture of solvents including Ethylbenzene were reported to express the effect on hearing, kidney DNA^?0." -ÍM Qỉ ugc V Hl CONCLUSION Concentration of ethylbenzene and styrene in the working environment - The maximum concentration of ethylbenzene and styrene at three research facilities was within the permissible limit Significantly, tire concentration of styrene in the environment is very low (1.13 i o.ộĩmg/m5) - 22 individual ethylbenzene concentrations samples in an average 8-hour at research facilities exceeded the permissible limit by ACGIH mainly in the mixing workshop The level of ethylbenzene contamination through Mandelic and Phenylglyoxylic acids metabolism products in urine - The average total concentration of MA and PGA in tile three companies were within the permissible limit according to the ACGIH but calculated for each subject 21 samples are exceeding the permissible limit - There is a strong correlation between ethylbenzene exposure and the metabolite in the urinary(MA and PGA) (R = 0.82) r-u -ÍM Qỉ Hgc V Hl REFERENCES Global trends on occupational accidents and diseases Accessed August 29, 2020 https:/Avww.ilo.oig/legacy/english/osh/en/story_content/extenial_files/fs _st_l -ILO_5_en.pdf Preventing disease through a healthier and safer workspace Accessed August 30 2020 https :/Avww who.int/publications-detail- redirect/preventing-disease-through-a-healthier-and-safer-workspace Persons outside the labour force: How inactive are they really Accessed August 29 2020 https:/Avww.ilo.org’wcmsp5/groups.'public/— dgreports/—staưdocuments'publication/wcms_714359.pdf ẢSTRAND I ENGSTRỒM J ÕVRUM p Occupational Poisonings: Lessons Learned front Poison Center Narratives Scandinavian Journal of Work, Environment & Health 1978;4(3):185-194 Roundtable on Environmental Health Sciences R Practice B on PH and PH Medicine I of The Challenge: Chemicals in Today's Society National Academies Press (US); 2014 Accessed August 29 2020 https: //WWW neb i nlm ni h g) v/books/NBK268889/ Guide to Occupational Exposure Values Published 2018 Accessed August 30 2020 hnps:/Avww.acgih.org/forms/store/ProđuctFonnPublic/2018-guide-tooccupational-exposure-values National Toxicology Program NTP Toxicology and Carcinogenesis Studies of Ethylbenzene Nati Toxicol Program Tech Rep Ser 1999:460:1-231 Humans IWG oil the E of CR to Cancer IA for R OIL Organization WH Ethylbenzene International Agency for Research on Cancer World Health Organization; 2000 -c -ÍM QỈ Hgc V Hl Chang F-K Mao I-F Chen M-L Cheng S-F Urinary 8- Hvdr oxydeoxyguanosine as a Biomarker of Oxidative DNA Damage in Workers Exposed to Ethylbenzene Ann Occup Hyg 2011;55(5):519-525 doi:10.1093/annhyg/merO 10 10 Toxicological Profile for Ethylbenzene :341 11 Gagnaire F Lai^lais c Grossmann s Wild p Ototoxicity in rats exposed to ethylbenzene and to two technical xylene vapours for 13 weeks Arch Toxicol 2006;81(2): 127 doi:10.1007/s00204-006-0124-y 12 Bộ Y tế Bệnh viêm da tiếp xúc dung mõi hừu người lao dộng vã giái pháp can thiệp Accessed August 30 2020 https://moh.gov vn'web/phong-chong-benh-nghe-nghiep'thong-tin-hoat" dong, 13 Hien NT Nhung DTC Hung NP Thuan BP Huy NQ Expression of CYP2E1 gene in paint workers occupationally exposed to organic solvents KVL* Journal of Science: Natural Sciences and Technology 2019:35(3) doi: 10.25073/2588-1140/\nunst.4893 14 About Ethylbenzene Accessed August 30 2020 https: //styrene org'about-ethylbenzene/ 15 KA WAI T SAKƯRAI H IKEDA M Biological monitoring of occupational ethylbenzene exposure by means of urinalysis for unmetabolized ethylbenzene Ind Health 2019;57(4):525-529 doi: 10.2486/indhealth 2018-0170 16 Lịch sư ngành Sơn Việt Nam Accessed August https://lamodepaintAii4ich-su-nganh-son-xiet-nam-cid32.html -ÍM Qỉ ugc V Hl 30 2020 17 Thòng tư 2X/2OI6 TT-BYT hướng dần quân lý bệnh nghe nghiệp Accessed August 30 2020 https://thuvienphapluat.vn/van-ban4ao-dong- tienluong.Thong-tu-28-2016-TT-BYT-huong-dan-quan-ly-benh-nghe- nghĩep319327.aspx s Sams c Loizou GD Cocker J Lennar d MS Metabolism of ethylbenzene by human liver microsomes and recombinant human cytochrome P450s (CYP) Toxicol Lett 2004;147(3):253-260 doi: 10.1016/j.toxlet.2003.11.010 19 Engstrốm K Riihimaki V Laine A Urinary disposition of ethylbenzene and m-xylene in man following separate and combined exposure Int Arch Occup Environ Heath 1984;54(4):355-363 doi: 10.1007/BF003 78589 20 Vàn bãn quy phạm pháp luật Accessed August 31 2020 http;//vanban.chinhphu.viVportal/page/portal/chinhphu/hethongvanban?cl ass_id= l£_page= l&mode=detail&document_id= 163 542 21 WHO Occupational and work-related diseases WHO Accessed August 31,2020 https://www.who.int/occupational_health/activities/occupational_work_d iseases/en/ 22 US EPA o W"hat is the definition of voc? US EP A Published March 15 2019 Accessed September 2020 hnps:/Avww.epa.gov/air- emissionsinventoriesAvhat-definition-voc 23 Humans IW’G on the E ofCR to Ethy lbenzene International Agency for Research on Cancer; 2000 Accessed September 2020 http6:/Avw\v.ncbi.nlm.nih.§Dv/books/NBK390915/ 24 Verschueren K Handbook of environmental data on organic chemicals 25 Martins EM Boiba PF de s Dos Santos NE Dos Reis PTB Silveira RS Correa SM The relationship between solvent use and BTEX concentrations r-u -ÍM Qỉ ugc V Hl in occupational environments Environ Mon it Assess 2016:188(1l):608 doi:10.1007/sl 0661-016-5621-S 26 ACGIH Threshold Limit Values (TLVs) and Biological Exposure Index (BEIs) for Chemical Substances and Physical Agents Published online Januaiy 1.2004 27 ethylbenzene_5O8.pdf Accessed August 26 2020 https://ntp.niehs.nih.gov7ntp/htdocs/chem_background/exsumpdfethylbe nzene_508.pdf 28 American Conference of Governmental Industrial Hygienists Threshold Limit Values and Biological Exposure Indices American Conference of Governmental Industrial Hygienists: 2012 29 Capella KM Roland K Geldner N et al Ethylbenzene and Styrene Exposure in the United States based on Urinary Mandelic Acid and Phenyl glyoxylic Acid: NHANES 2005 - 2006 and 2011 -2012 Environ Res 2019:171:101-110 doi:10.1016/j.envres.2019.01.018 30 ATSDR - Toxicological Profile: Ethylbenzene Accessed September 1, 2020 hnps://vwwv.atsdr.cdc.gov/ToxProfiles/TP.asp?id=383£tid=66 31 Mortis Broun L Moradi T Gridley G Plato N Dosemeci M Fraumeni JF Exposures in tile Painting Trades and Paint Manufacturing Industry and Risk of Cancer Among Men and Women in Sweden: Journal of Occupational and Environmental Medicine 2OO2;44(3):258-264 doi: 10.1097/00043764200203000-00013 32 Oliveira HM de Dagostim GP Mota A da s Tavares p Rosa LAZC da Andrade VM de Occupational risk assessment of paint industry workers Indian Journal of Occupational and Environmental Medicine -c -ÍM CỊỈ Hgc V Hl 2011;15(2):52 Accessed May 17, 2021 https://www.ijoem.com/article.asp7iss n=097322S4;vear=2011 ;volume= 15;issue=2;spage=52;epage=58:aulasr=de:type =0 33 Angerer J, Wulf H Occupational chronic exposure to organic solvents XI Alkylbenzene exposure of varnish workers: effects on hematopoetic system Im Arch Occitp Environ Health 1985;56(4);307-321 doi:10.1007/BF00405272 34 Baidodej z, Eva B Màlek B Value and Application of Exposure Tests XI Exposure Test for Styrene Ceskoslovenska Hygiena 1961 ;6(9):546552 Accessed May 17, 2021 https://www.cabdirect.org/cabdirecVabstract/19622705161 35 de Oliveira HM Dagostim GP da Silva AM Tavares p da Rosa LAZC de Andrade VM Occupational risk assessment of paint industry workers Indian J Occitp Environ Med 2011:15(2):52-58 doi: 10.4103/00195278.90374 36 Biological monitoring of standardized exposure to ethylbenzene: Evaluation of a biological tolerance (BAT) value I Request PDF ResearchGate doi: 10.1007/S002040050018 37 Bardodej z Eva B Value and Application of Exposure Tests X Exposure Test for Ethyl Benzene Ceskoslovenska Hygiena 1961;6(9):537-545 38 Assessment ƯENC for E 2018 TLVs aid BEIs: Based on the documentation of the threshold limit values for chemical substances and physical agents & biological exposure indices Published March 15 2009 Accessed May 17, 2021 https://hero.epa.gov/hero index.cfinTeference/details/reference_id./4716154 39 Jang J-Y Droz PO Kim s Biological monitoring of workers exposed to ethylbenzene and co-exposed to xylene International Archives of -ÍM QỈ Hgc V Hl Occupational and Environmental Health 2000;74(l):31-37 doi: 10.1007/S004200000181 40 Janasik B Jakubowski M Jalowiecki p Excretion of unchanged volatile organic compounds (toluene, ethylbenzene, xylene and mesitylene) in mine as result of experimental human volunteer exposure Int Arch Occup Environ Health 2008;81(4):443-449 doi:10.1007/s00420-007- 0233-9 41 Bardodej z Bardodejova E Biotransformation of ethyl benzene, styrene, and alpha-methylstyrene in man Am Ind Hyg Assoc J 1970:31(2):206- 209 doi: 10.1080/0002889708506230 42 Inoue o Seiji K Kudo s et al Urinary Phenylglyoxylic Acid Excretion after Exposure to Ethylbenzene among Solvent-exposed Chinese Workers International Journal of Occupational and Environmental Health 1995; (1): -8 doi: 10.117 9/oeh 1995.1.1.1 43 Szucs s Tóth L Legoza J Sárváry A Adány R Simultaneous determination of styrene, toluene, and xylene metabolites in urine by gas chromatography/mass spectrometry Arch Toxicol 2002;76(10):560-569 doi: 10.1007/S00204-002-0384-0 44 Simultaneous HPLC Determination of Urinary Metabolites of Toluene, Xylenes, and Ethylbenzene: and Its Application to Biological Monitoring of Tunisian Workers Exposure I Request PDF ResearchGate doi: 10.1080/00032710500423419 45 Vietnamese painting market to be exciting in 2019 Vietnamese painting market to be exciting in 2019 Accessed May 17 2021 https7/coatingsvietnam.com/en/news/vietnaniese-painting-market-to-be-exciting-in- 20192-91.html -ÍM Qỉ ugc V Hl 46 Xây dựng quy trinh kỳ thuật định lượng axit mandelic sân phẩm chuyên hóa cua cthylbcnzen nước tiếu bàng phương pháp sắc ký long khối phổ Accessed May 17 2021 http://vnniosh.vn/chitiet_NCKH/id/19731/Xay-dung-quy-trinh-ky-thuatdinh-1 uong-axit- mandeli c-%E2%S0%93 -san-pham- chuyen-hoa-cuaethylbenzen-trong-nuoc-tieu-bang-phuong-plìap-sac-ky-long-khoi-pho 47 Thưởng qui kf thuật Súc khõe nghề nghiệp mòi trường Accessed May 17 2021 http://vnniosh.xTt/Details/id/5199/Thuong-qui-ki-lhuat-Suc- khoenghe-nghiep-va-moi-tniong 48 Laboratory Procedure Manual :60 49 Junge w Wilke B? Halabi A, Klein G Determination of reference intervals for serum creatinine, creatinine excretion and creatinine clearance with an enzymatic and a modified Jaffe method Clin chim Acta, 2004:344(1-2): 137-148 doi;10.1016/j.cccn.2004.02.007 50 Quyct định 3733/2002/QĐ-BYT 21 tiêu chuẩn vệ sinh lao động 05 nguyên tắc vả 07 thõng sổ vệ sinh lao dộng Accessed May 17 2021 https://thuxTenphapluat.x-n/xan-banThe-thao-Y-te/Quyet-dinh-3733- 2002QD-BYT-2 l-tieu-chuan-ve-sinh-lao-dong-05-nguyen-tac-xa-07- thong-soxe-sinh-lao-dong-70480.aspx 51 ACGIH Threshold Limit Value for Chemical Substances and Physical Agents and Biological Exposure Indices Published online 2018 52 Tạ Thị Thao Giáo Trình Mơn Học Thống Kè Trong Hỏa Phàn Tích Trường Đại học Khoa học Tự nhiên Đại học Quốc Gia Hà Nôi.; 2010 53 Martins EM Boiba PF de s Dos Santos NE Dos Reis PTB Silveira RS Correa SM The relationship between solvent use and BTEX concentrations in occupational environments Environ Mon If Assess 2016; 88(1 l):608 doi:10.1007/sl 0661-016-5621-8 54 Heibati B Pollitt KJG Karimi A et al BTEX exposure assessment and -ÍM CỊỈ Hgc V Hl quantitative risk assessment among petroleum product disuibutors Ecoioxicol Environ Saf 2017;144:445-449 doi: 10.1016/j.ecoenv 2017.06.055 55 El-Hashemy MA, Ali HM Characterization of BTEX group of VOCs and inhalation risks in indoor microenvironments at small enterprises Sci Total Environ 2018:645:974-983 doi: 10.1016/j.scitotenv.2018.07.157 56 Carrieri M, Tranfo G Pigini D el al Correlation between environmental and biological monitoring of exposure to benzene in petrochemical industry operators Toxicol Len 2010:192(l):17-21 doi:10.1016/j.toxlet.2009.07.015 57 Environmental and biological monitoring of benzene, toluene, ethylbenzene and xylene (BTEX) exposure in residents living near gas stations - PubMed Accessed May 17 2021 https://pubmed.ncbi.nlm.nih.gov/31266404/ 58 Bairos N, Carvalho M Silva c et al Environmental and biological monitoring of benzene, toluene, ethylbenzene and xylene (BTEX) exposure in residents living near gas stations J Toxicol Environ Health J 2019;82(9):550-563 doi: 10.10S0/15287394.2019.1634380 59 Durmusoglu E Taspinar F Karademir A Health risk assessment of BTEX emissions in the landfill environment J Hazard Mater 2010:176(l-3):870877 doi:10.1016/j.jhazmat.2009.11.117 60 Tunsaringkam T Siriwong XV Rungsiyothin A Nopparatbundit s Occupational exposure of gasoline station workers to BTEX compounds in Bangkok Thailand IntJ Occup Environ Med 2O12;3(3): 117-125 61 Badjagbo K, Loranger s Moore s, Tardif R Sauvé s BTEX Exposures among Automobile Mechanics and Painters and Their Associated Health Risks Human and Ecological Risk Assessment: An International Journal 2010:16(2):301-316 doi: 10.1080/10807031003670071 -c -ÍM Qỉ ugc V Hl 62 Kitwattanavong M Prueksasit T Morknoy D Tunsaringkarn T Siriwong w Health Risk Assessment of Petrol Station Workers in the Inner City of Bangkok Thailand, to the Exposure to BTEX and Carbonyl Compounds by Inhalation Human and Ecological Risk Assessment: An International Journal 2013;19(6):1424-1439 doi:10.1080/10807039.2012.6S5S14 63 Peibellini L Pasini F Romani s Princivalle A Brugnone F Analysis of benzene, toluene, ethylbenzene and m-xylene in biological samples from the general population J Chromatogr B Analyt Technol Biomed Life Sci 2002;778(1 -2): 199-210 doi: 10.1016/S037S-434 7(01 )00446-7 64 Cui sw Pan XF Yan HF [Determination of phenyl glyoxylic acid and mandelic acid in urine by high performance liquid chromatography method] Zhonghua Lao Dong ỉĩei Sheng Zhi Ye Bing Za Zlu 2017:35(10):774-776 doi:10.3760/cma.j.issn.1001-9391.2017.10.018 65 American Conference of Governmental Industrial Hygienists Documentation of the Threshold Limit Vales and Biological Exposure Indices 7th edition ACGIH Cincinnati OH" ACGIH Cincinnati OH Published online 2014 66 Oh HH Park H Kim DH et al The relationship between urinary BTEX metabolites and residence setting among Korean homemakers: the first Korea National Environmental Health Survey (2009-2011) Annals of Occupational and Environmental Medicine 2017;29(l):38 doi: 10.1186/S40557-017-0189-5 67 Inoue null Seiji null Kudo null, et al Urinary Phenylglyoxylic Acid Excretion after Exposure to Ethylbenzene among Solvent-exposed Chinese Workers Int J Occup Environ Health 1995:1(1): 1-8 doi: 10.1179/oeh 1995.1.1.1 68 Jacobsen p Hein HO Suadicani p Pairing A, Gyntelberg F Mixed solvent exposure and hearing impairment: an epidemiological study of 3284 men -ÍM QỈ Hgc V Hl The Copenhagen male study Occup Med (bond) 1993:4 3(4): 180-184 doi: 10.1093/occmed/43.4.180 69 Korn M Gfrdrer w Herz R Wodarz I XVodarz R Stereometabolism of ethylbenzene in man: gas chromatographic determination of urinary excreted mandelic acid enantiomers and phenylglyoxylic arid and their relation to the height of occupational exposure Z/tf Arch Occup Environ Health 1992:64(2):75-78 doi:10.1007/BF00381472 r-u -ÍM Qỉ ugc V Hl Appendix PERSONAL INFORMATION SHEET A Personal information Subject ID Year of birth Sex l.Male 2-Female Current job title Name of companies Working hours: /per day /permonth ó.Educatỉon level No schooling completed Teclinical workers u □ □ □ Primary school Secondary School High school Vocational college College, university and postgraduate u □ □ How long have you been working your current job? year month B SOME CHARACTERISTICS IN WORKING Do you know about labuor safety rales during working? Yes 77] Moderate [777] No Q Do you use personal protective equipment during working? Regularly [ 2.Sometimes ; ] 3.No| | What kind of personal propective equipment you use? ■ Gloses [77] Hat EJ Clothing Glasses 77] Shoes [77] Masks c Living habits Have you ever smoked tobacco? Yes: □ No: [7] Are you smoking currently? □ [777] Yes:!~] No: Q If yes how many cigarettes'day you smoke? How many years have you smoked? 20 □ Appendix Chemical measuring results in the working environment Name Of Compan No y Total Total Of workers Ethylbenzene Styrene Total Exposedworkers (1) (2) (1) (2) (1) (2) ... lack of research on Ethylbenzene contamination in workers Therefore, the research is "Determination of urinary Mandelic and Phenylglyoxylic acids in ethylbenzeneexposed paint manufacturing workers. .. To determine the level of urinary Mandelic and Phenylglyoxylic acids in ethylbenzene- exposed paint manufacturing workeis in 2019 -ÍM CỊỈ ugc V Hl CHAPTER LITERATI RE REMEW 1.1 Concepts and derm... by Paint Company with 0.89 ± 1.01 mg /m3 and the paint company with 0.69 ± 0.82mg/m3 3 33 The level of urinary MA and PGA in 3ethylbenzene- exposed paint manufacturing workers Table 8: Urinary