Occupational Health Research in Taiwan

Transcription

1 Industrial Health 2004, 42, Review Article Occupational Health Research in Taiwan Tung-Sheng SHIH 1, Ho-Yuan CHANG 2 *, Wen-Yu YEH 1, Teh-Sheng SU 3, Yi-Shiao HUANG 4, Cheng-Ping CHANG 1, Jiune-Jye HO 1 and Yueliang Leon GUO 2 1 Institute of Occupational Safety and Health, Council of Labor Affairs, No. 99, Lane 407, Heng-Ke Rd., Sijhih City, Taipei, Taiwan 221, Republic of China 2 Department of Environmental and Occupational Health, College of Medicine, National Cheng Kung University, 138 Sheng-Li Road, Tainan, 704 Taiwan, Republic of China 3 Council of Labor Affairs, Taipei, Taiwan, Republic of China 4 Center for Environmental, Safety and Health Technology, Industrial Technology Research Institute, Hsin Chu, Taiwan, Republic of China Received February 20, 2004 and accepted March 1, 2004 Abstract: This article gave a brief introduction of population, labor force, general status of occupational safety and health in Taiwan. Statistics of occupational injuries and health disorders, laws and regulations relevant to occupational health were also covered. Research activities driven by universities, research institutes, society/association were provided. Two multi-lateral collaborative research examples were presented: an intoxication outbreak-initiated CS 2 study and an informationdemand-motivated 2-methoxy-ethanol study. Industrial hygienists, engineers, epidemiologists, and occupational physicians from both universities and research institutes, governmental agencies, and from non-profit R&D organizations and academic associations were involved in these researches, presenting a promise that integrated collaboration of inter-disciplinary specialty cooperated with governmental participation could benefit not only academic achievement, governmental policymakeup, but also to the employees themselves. Key words: Occupational safety, Occupational health, Carbon disulfide, 2 methoxy ethanol, Research activities, Nationwide survey Background Information Taiwan s total population was million and a labor force of million as of 2003, and 9.68 million workers were paid by specific employer(s) (Table 1). In the same year, gross national product (GNP) was US$ billion, with per capita GNP reaching US$ 13,167 1). Average monthly income per employee in industry and service sector was US$ 1,205. Stepping into the 21 th century, Taiwan keeps moving forward to a new knowledge economy era based on continuous advances in microelectronics, computer, telecommunication, synthetic materials, robotics, and biotechnology. The increasing demand for technical and professional personnel can be expected in contrast to the decreasing work forces in agriculture and in production. As a result, agriculture s contribution to the total economy continued to decline, now only accounting for 1.6% of the gross domestic production (GDP) and the service sector accounting for 67% as same as that of On the other hand, the contribution from industries continuously arises to 31.4% in 2003 from 31.1% in ). *To whom correspondence should be addressed.

2 OCCUP HEALTH IN TAIWAN 125 Table 1. Work force distribution in industries in Taiwan (December, 2003) Category Number of worker Percentage of total workers (1,000) labor force Agriculture, forestry, fishing & animal husbandry % Industry 3, % Mining, quarrying % Manufacturing 2, % Electricity, gas, water % Construction % Commerce 2, % Transport, storage & communication % Service 2, % Public administration % Total 9, % General Status of Occupational Safety and Health Undergoing with a rapid industrial transformation, Taiwan experienced in encountering some challenges, such as considerably high frequencies of occupational injuries and diseases. Safety and health problems associated with traditional manufacturing industries sustain to threaten workers health. Up to the present time, the workers in the traditional industries still account for considerable portion of the labor force. Moreover, small and medium scale enterprises predominate in local industries in Taiwan and up to 77.7% of labor force are employed by them. Statistics of workers compensation from Labor Insurance Statistics revealed occupational injury rate per thousand fell dramatically from 5.91 in 1987 to 3.06 in 1996, but rose to 4.41 in 1999 again. In 2002 there were 36,326 incidences of occupational injury disabilities and deaths for all industries or in average 4 workers injured, disable or died on the job every hour. Table 2 showed the cases suffered from temporary disability, permanent disability and death resulting from occupational injuries under Labor Insurance Statistics since ). Both cases of temporary and permanent disability increased by 2000, and decreased as an average of in However, deaths remain a declining tendency due to the implementation of some activities driven by the Council of Labor Affairs (CLA), Executive Yuan (Cabinet) since the year of The Labor Insurance Statistics also showed that less than 200 compensation claims for occupational disease were put in prior to However, the number of the compensation claims had ever increased by 2000 because the compensation criteria for coal workers pneumoconiosis was reduced in Nevertheless, on top of pneumoconiosis and its related Table 2. Occupational injuries rate per thousand ( ) in Taiwan from 1999 to 2003 reported by Labor Insurance Statistics Year Total Hospitalization Permanent over 4 d disability Death (33,709) (28,244) (4,815) (650) (38,862) (33,053) (5,207) (602) (38,386) (33,004) (4,839) (543) (36,326) (31,363) (4,456) (507) 2003 a (29,547) (25,922) (3,287) (336) a: Cases were counted by October, complication, the incidence of reported occupational diseases was still relatively low compared to that in other countries. In general, workers, employers, and even physicians have relatively poor understanding of occupational diseases possibly due to the lack of knowledge. Table 3 showed the distribution of occupational diseases since Department of Health (DOH), on the other hand, manages another hospital-based notification system for suspicious occupational diseases. Table 4 is the case number for who were diagnosed as a possible or probable work-related disease from 1999 to 2001 by registered physicians. Suspicious cases, however, are not mandatory to be reported by physicians; consequently, further inference is difficult owing to no denominator of workers being covered. Musculoskeletal disorders such as low back pain have recently become one of the most common occupational diseases if excluding pneumoconiosis. Fifty-two percent

3 126 TS SHIN et al. Table 3. Case number of occupational diseases in Taiwan from 1999 to 2003 reported by Labor Insurance Statistics a Disease categories b Skin disorder Pneumoconiosis c 2, Occupational low back pain Arm, neck & shoulder diseases Hearing loss Poisoning or intoxication Decompression Vibration Cancers related to occupation Other diseases Total workers with occupational disease 2,797 1, a: Consisting of the cases of hospitalization over 4 d, permanent disability and deaths. b: Cases were reported by October of c: 14,973, 3,491, 572 and 661 cases in 1999, 2000, 2001, and 2002 were not included, respectively, because these coal workers were unemployed as a result of pneumoconiosis. workers complained of musculoskeletal aches in a recent survey, indicating ergonomic intervention is needed 4). Occupational Safety and Health Organizations Taiwan has one of the fastest growing economy, having achieved an average annual growth rate of 10% since 1970s, but down to 3.15% in the year of 2003 due to worldwide economical bust. One of the main reasons for the growth in 1970s was the continuous expansion of the manufacturing industry. Acknowledging the importance of the labor issues, the Council of Labor Affairs (CLA), a governmental agency in ministry level under the central governmental cabinet was established in CLA is also the highest authority in setting up the occupational health and safety (OHS) regulations, systems, and performing the labor inspection. Labor Safety and Health Directorate (LSHD) and Labor Inspection Directorate (LID) are the two branches related to OHS affairs in CLA. Under CLA, there are two local inspection offices located in special district areas (Taipei and Kaohsiung cities) and three regional inspectorates in northern, middle, and southern Taiwan, respectively. The Institute of Occupational Health and Safety (IOSH) was further established in 1992 subordinate to CLA to conduct the researches regarding the OHS in Taiwan. Other institutes under the central governmental cabinet related to OHS other than CLA/IOSH are described as follows: Bureau of Health Promotion (BHP) involved in some health promotion programs in workplace. Center for Disease Control (CDC) is responsible for the control of infectious diseases. National Health Research Institutes Table 4. Case number of being diagnosed as a possible or probable work-related disease from 1999 to 2001 by registered physicians Disease categories n % Decompression 1, Occupational trauma Pneumoconiosis Needlestick injury Hearing loss Skin disorder Carpel Tunnel Syndrome Others Total 3, (NHRI) has a branch, Division of Environmental Health and Occupational Medicine, involved in the research on environmental and occupational medicine. BHP, CDC, and NHRI are all subordinate to Department of Health (DOH). Council of Atomic Energy is in charge of radiation protection. National Science Council provides some budgets for research on OHS and conducts promotion of administrative management of OSH in several Science Based Industrial Parks. Environmental Protection Unit under the Ministry of Education is responsible for the OHS in universities and schools. Center for Environmental, Safety and Health Technology Development, a branch under the Industrial Technology Research Institute (ITRI), provides customized services in OHS and other environmental aspects to the general industries. The Bureau of Industry (BOI) aims to upgrade the manufacturing facilities and is also involved in Industrial Health 2004, 42,

4 OCCUP HEALTH IN TAIWAN 127 Fig. 1. Governmental organizations in Taiwan associated with occupational safety and health (OHS) affairs. Institutions abbreviation used in this figure: CLA: Council of Labor Affairs; LSHD: Labor Safety and Health Directorate; LID: Labor Inspection Directorate; IOSH: Institute of Occupational Health and Safety; BHP: Bureau of Health Promotion; CDC: Center for Disease Control; DEHOM: Division of Environmental Health and Occupational Medicine; NHRI: National Health Research Institutes; DOH: Department of Health; CAE: Council of Atomic Energy; NSC: National Science Council; SBIP: Science Based Industrial Parks; EPU: Environmental Protection Unit; MOE: Ministry of Education; CESH: Center for Environmental, Safety and Health Technology Development; ITRI: Industrial Technology Research Institute; BOI: Bureau of Industry; EPZA: Economic Processing Zone Administration; MOEA: Ministry of Economic Affairs. Line stands for the relationship between institutions. Solid line: directly subordinated, dotted line: indirectly affiliated. the improvement of working conditions. OHS related affairs in several Economic Processing Zones are managed by Economic Processing Zone Administration (EPZA). Basically, ITRI, BOI, and EPZA belong to Ministry of Economic Affairs. A schematic diagram is referred to Fig. 1 to describe the infra-structure and their inter-institutional relationships. Laws and Regulations Relevant to Occupational Health The major law relevant to occupational health in Taiwan is the Labor Safety and Health Law (LSHL), which was promulgated in 1974 and amended in This law is enacted for the purpose of preventing occupational accidents and protecting labor safety and health. A total of 4.14 million of labors and 279 thousand of firms were covered by this law. Under the mandate of the Law, more than 25 occupational health related standards or regulations have been established by CLA. For example, the regulation regarding the exposure monitoring mandates a list of hazardous chemicals requiring monitor, the recommended sampling and analytical methods, the sampling strategy, and the qualifications of the certified sampling personnel as well as accredited industrial hygiene laboratories for compliance purpose. More than 480 chemicals have been put in the list of Permissible Exposure Limits (PELs). The Labor Health Protection Regulation mandates employers to perform pre-employment physical examination for new labors at the time of employment, as well as periodical health examination during employment. Where labors are subject to particularly hazardous operations or chemicals, specific health examinations shall be performed on a regular basis. Health surveillance booklets shall be prepared and distributed to labors. Moreover, the Labor Standard Law states, The employers are responsible for preventing from occupational hazards, establishing adequate work and welfare facilities for their employees. Therefore, the Labor Inspection Law, enacted to implement labor inspection system, enforce labor laws, protect the labor-management rights and benefits, and maintain the stability of the society to maintain economic development. Currently, total 277 inspectors achieved an

5 128 TS SHIN et al. amount of 71,848 safety/health inspections, of 10,094 general working condition inspections, covering 10.2% of all firms in However, the labor inspection now prioritizes in the safety issue in some particular industries such as construction industries. For example, a total of 4,162 inspections were relevant to standard/act of work environment monitoring and labor health protection, accounting for only 3% among all inspections. Occupational Health Issues that Have Been Causing Social Concern in Recent Years Quite a few new occupational health issues have recently caused public attentions in Taiwan. Divers disease resulting from abnormal pressure in subway construction worksites in Taipei City has become one of the most concerned occupational health issues in Taiwan. Occupational respiratory disease, especially free crystalline silica induced silicosis, is also an important issue. Other occupational health issues including the biological hazards caused by infectious diseases like severe acute respiratory syndrome (SARS) to the health care workers, workers handling the contaminated clothing and wastes, and bird flu to the agricultural workers; psychological stress control and health promotion for occupational drivers (taxi drivers, long distance bus and truck drivers), stock exchange workers, air traffic controllers; safety and health protection of handicapped workers and aboriginal workers. Psychological strain and ergonomic stresses for the white-collar and high-tech employees, and other newly emerging challenges become a new frontier waiting for further OHS efforts. More effective integration of the limited resources from different ministries is also an urgent need. To upgrade the quality of professional training, the CLA has collaborated with the MOE to set up three educational resource centers and encourage the professors in safety and health departments in universities to actively participate in the training and education program for college students and occupational safety and health professionals of enterprises. Improvement of working conditions and upgrading of workers safety and health awareness in small business are also important in Taiwan since over than 80% of the enterprises have workers less than 30 people. A new consultation programs to adequately provide financial support and technical needs to those small businesses has been just initiated. Occupational contact dermatitis among cement workers and female workers in barbershops and beauty salons has also ever caused great concerns in this country. Research Activities In Taiwan, about twenty departments related to OHS are deployed in universities and colleges, among them, about half (10 departments) own graduate programs. There are also a number of academic OHS-related associations like Aerosol Science Association, Ergonomics Association, Industrial Hygienists Association, Occupational Physicians Association, and Occupational Nurses Association. At least one or two international conferences focusing on OHS are held annually. Normally, the conference is organized by an academic association or a university, and is sponsored by governmental agencies like CLA, DOH, and MOE. Quite a few researches in locating the underlining causes of occupational disease or outbreak have been successfully performed by independent researchers or scholars from universities and colleges and appreciable results have been continuously obtained 5 18). The participation of governmental agency, however, might be more resourceful in setting up a nationwide surveillance program or develop a control remedy or for further corresponding policy-making 19, 20). Basically, Fig. 2 shows an IOSH-driven research example incorporating a multi-dimensional scheme of an integrated approach to the recognition, evaluation, and the provision of the control remedy to OHS problems. To calibrate the diagnosis of occupational diseases among occupational physicians, more than 100 guidelines have been developed by CLA in the past 3 yr. To build up a comprehensive database to better understand who and how serious the workers currently or potentially exposed to occupational hazards, reliable monitoring measures should be developed in advance. The standard or reference analytical method should be established, the personnel who perform sampling in the field should be certified, and the laboratory responsible for the sample analysis should be accredited. Up to the present time, more than 200 recommended sampling and analytical methods for hazardous chemicals have been developed and validated by 6 core laboratories since Moreover, more than 1,200 personnel have been certified in performing the sampling for chemical and physical stresses in worksite. Since the year of 1992, analytical laboratory accreditation program has been implemented and proficiency testing samples prepared by a neutral institute ITRI, have been sent to participating laboratories quarterly a year. Up to 2001, laboratories have been actively participating in this round robin test, using mixture matrix with different concentrations and analytes. Double blind samples were tested twice a year and a field evaluation by an ad hoc team has been executed since Using the reliably Industrial Health 2004, 42,

6 OCCUP HEALTH IN TAIWAN 129 Fig. 2. An IOSH-driven research example incorporating a multi-dimensional scheme of an integrated approach to the recognition, evaluation, and the provision of the control remedy to OHS problems. The sequential notes used in this figure please refer to the text. aforementioned sampling and analytical methods, more than 30 industries have been identified as high risk occupations, revealing about one half of the investigated industries have exposures over the permissible exposure limits after the completeness of continuous nationwide exposure survey program during Moreover, hazard communication system for hazardous and dangerous chemicals (HCSHDC) including labeling, the development of material safety data sheet, as well as training and education has been stringently implemented since 1989 to avoid or diminish the risk resulting from workers unawareness of hazards in the workplace. The HCSHDC system in Taiwan was modified from US Hazard Communication Standard, British COSHH (Control of Substances Hazardous to Health Regulations), Canadian WHMIS (The Workplace Hazardous Materials Information System) and systems from Japan and European countries. A new GHS (Globally Harmonized System) for classification and labeling for the hazardous chemicals in the workplace has been actively campaigned in this country. In parallel, investigation of workers awareness of safety and health condition in workplace has been commenced once every 3 yr since 1989 and 20,000 workers were interviewed face to face in each investigation. The understanding of their awareness of OHS enriches the basis of further related policy-making. More advanced health promotion programs including the nationwide exposure surveys, hearing conservation program, and respiratory protection program have also been set up. Furthermore, in view of the advancing knowledge as well as the consideration of possible difference in exposure scenario and susceptibility to hazard-induced diseases between our workers and those in literature (mostly, Caucasian), an ad hoc recommended exposure limits (RELs) committee was organized by IOSH since This committee is scheduled to review and recommend RELs for five chemicals each year. Empirical Examples of Industrial Health Intervention Researches: 2-methoxy Ethanol vs. Carbon Disulfide To illustrate the integrated efforts of research and administrative management, the following two examples are given to show the different approaches in research on problem recognition, evaluation, and control driven by IOSH. Figure 3 is the schematic diagram for the research in 2-methoxy ethanol (abbreviated as 2-ME). In this example, IOSH initiated and managed the whole research components. 2- ME has been widely used as the de-icing additive in military jet fuel and solvents in semiconductor industries in Taiwan and many other countries due to its extensive miscibility with water and most common organic solvents. Animal

7 130 TS SHIN et al. Fig. 3. A schematic diagram of integrated studies on 2-ME. The sequential notes used in this figure please refer to the text. studies and limited human volunteer studies revealed that the exposure to 2-ME might adversely affect the reproductive, developmental and hematological systems. However, the information with respect to the occupational exposure status, the appropriate biomarker of occupational exposure, the health impacts to the exposed workers, and the sequent control strategies in preventing workers from the exposure to 2-ME were very limited. IOSH initiated a multi-year program project to capture a comprehensive picture of 2- ME-related OHS aspects since Environmental monitoring on the 2-ME-exposed workers to obtain their general exposure levels might be the first step to move forward. However, conventional sampling by pumpmotivated devices caused substantial difficulties from the workers in a nationwide or large-scale monitoring. Passive sampling, owing to its light weight, small volume, easy of operation, and low demand for maintenance and calibration, might be an appropriate alternative to accommodate such a condition. The climatic condition of high temperature and humidity in Taiwan, however, could cause a significant interference in sampling, especially for high polar compounds such as 2-ME. Our field study demonstrated that at low sampling rate the passive badges could provide comparable results as that of traditional active samplers with minimal influence of environmental factors 21). Due to wide interindividual variability of hygienic status and personal susceptibility, the biomarker levels determined from workers bio-specimen might be more appropriate to evaluate the truly exposed dose or toxicity equivalence especially for high skin permeable chemicals like 2-ME. The toxic metabolite of 2-ME, 2-methoxy acetic acid, in urine and in plasma, was demonstrated to be good biomarkers to reflect occupational exposure of 2-ME 22 24). In the field study, the investigators noticed that the workers might be exposed to 2-ME both in vapor and liquid forms via skin route. Further investigations demonstrated that the dermal absorption was the major 25, 26) exposure route of 2-ME vapor and liquid. New device for measuring an absorbed dose of gas/vapor by skin was developed (ROC patent No. 106,800 and US patent No. 5,984,868). Through a-week-long field study, urinary biomarkers via five consecutive working days revealed that accumulation of 2-ME uptake in a regular occupational setting could occur. In view of these findings, a suggested value for biological exposure index (BEI) collected at Friday post-shift was recommended to evaluate weekly mean exposure to 2-ME 27). Hematological manifestations were observed for those who occupationally exposed to 2-ME 28), and shortly after a cessation of the exposure, the workers could get recovery 29). Moreover, an improvement program of the working condition was achieved in a semiconductor copper laminate circuit manufacturing plant, and over 95% of exposure reduction (from 860 ppm to 27 ppm) was found after the enclosure of the coating area of machine. The successful experience provided a strong basis to use the similar algorithm to improve other manufacturing processes in reducing the exposure to 2-ME. Moreover, field studies also showed wearing impermeable rubber gloves during highrisk tasks can reduce major ME exposure 30). Based on the findings from longitudinal nationwide exposure surveys IOSH recommended lowering down the current PEL (from 25 ppm to 5 ppm) and set up a new BEI for 2-ME. The completeness of this series of 2-ME studies, not only provided better protection of workers health, reduced the exposure with a more technically and economically feasible Industrial Health 2004, 42,

8 OCCUP HEALTH IN TAIWAN 131 way, but also provided a better scientific basis for occupational health regulation setting of 2-ME. Another research example regarding the workers exposed to carbon disulfide (CS 2 ), presents another pattern in which investigators involved were from a more varied pool from different universities, research institutes and hospitals. An outbreak of neuropathy in a viscose rayon factory was reported in , 32). In response to that episode, IOSH conducted a multi-year monitoring program for this factory encompassing environmental monitoring and biological monitoring in addition to physical health examinations 33). Again, the inconvenience during field study triggered an improved method advanced in sampling and analysis applicable in workplace 34). Novel devices capable to monitor the workers exposure time, activities, and intensity on the real-time basis were developed using SnO 2 and IR real-time sensors (Method for Monitoring Exposure Time of Workers in Workplace: US Patent No. 10/179,181; Method and Device for Monitoring Worker s Exposure Pattern at Workplace: ROC Patent No ). Similarly, to avoid sophisticate and time-consuming procedure during sample preparation in the determination of 2-thiothiazolidine-4-carboxylic acid (TTCA) in urine, a recommended biomarker of CS 2 exposure, by gas chromatography, a sensitive and reliable analytical method using high performance liquid chromatography (HPLC) was developed in response to the need in a largescale field study 35). Biological monitoring study conducted in the viscose rayon factory found the elimination of urinary TTCA following the first-order kinetic pattern with a halflife about 8 hours 36). Following a-week-long consecutive monitoring for the workers, a linear accumulation trend for daily TTCA across the workdays was found for the workers with 12-h work shift 37). Biological monitoring study also revealed that the personal factor like host s skin disease possibly affects the relations of urinary TTCA to the occupational exposure to CS 2. Workers with susceptible skins, therefore, should either be assigned to work in areas without contacting hazardous materials directly or required to wear appropriately protective clothing 38). Attributing to the long-term follow-up with the CS 2 -induced intoxication victims, more findings in helping patients in rapid recovery and understanding better in the mechanism of CS 2 -induced parkinsonism and neuropathy were achieved 39 41). Recent in-depth study from the field investigation further discovered that elevated triglyceride and decreased high density lipoprotein levels in workers occupationally exposed to CS 2 42), and combined exposure to CS 2 and noise could result in the aggravation of hearing loss for the workers 43). The aforementioned research examples revealed two research patterns. CS 2 study was initiated from an intoxication outbreak. Physicians with specialty in the intoxication related (neurologists in this case) were first involved. Similar to other occupational intoxication outbreaks occurred previously, research findings greatly enrich toxicant- disease relationship. Sequential participation of industrial hygienists, engineers, epidemiologists, physicians with other specialty, particularly in occupational medicine, provided a wide-spectrum capability to examine such an outbreak from every possible direction. Therefore, in this case, new devices in environmental monitoring more applicable to the field study could be invented, suitable biological monitoring strategies could be set up, other health effects not firstly reported could be discovered, and effective control remedy or prevention measures could be recommended. The last but not the least, the participation of legal institutions like CLA inspectors and IOSH greatly improve the accessibility in the cooperation of the employers and employees. Most importantly, their participations not only enrich the scientific aspects, but also help in setting up a more thorough policy to prevent the workers from the further hazards on a legal basis. 2-ME study, on the other hand, was not driven by an outbreak originally. In view of the continuous advancing of semiconductor industries in Taiwan and the increasing demand for such a chemical given very limited information of health impact in hand, a team encompassing industrial hygienists, occupational physicians, epidemiologists, engineers was organized. National surveillance was campaigned to have a better understanding of general status in the aspects of exposure and health. Contributing to the participation of scholars from both universities and research institutes, governmental officers, and consultants from non-profit R&D organizations like ITRI, the teamwork on 2-ME has resulted in the establishment of another successful example, which encompasses a broad components of academic achievement, technology advancement, nationwide database buildup, adequate recommendation to the enterprises, and regulation revision. These two examples present a promise that integrated collaboration of inter-disciplinary specialty cooperated with governmental participation could benefit not only academic achievement, governmental policy-makeup, but also to the employees themselves. Advances in Research Pneumoconiosis is one of the most concerned occupational diseases in Taiwan. The aerosols generated via mechanical, abrasive, grinding, and vapor condensation are very likely

9 132 TS SHIN et al. to occur in the regular occupational environments. Due to different generation sources and drives, aerosols might be quite different in their shapes, size distribution, and electrostatic charge. Thus, industrial hygienists have been facing the continuous challenges in the accurate determination of different aerosol. IOSH continued sponsoring researchers in universities to develop new samplers. As a result, novel cyclone and porous foam sampler have been developed to avoid the static charge interference, leakage, loading capacity during sampling 44 47) and for collecting the liquid aerosols 48,49) (US Patent No , European Patent No , ROC patent No ). Virtual cyclone has been developed for size-selected sampling and sequential tests in laboratory and field have demonstrated its closer fitting the most recent internationally accepted 50, 51) respiration efficiency curve than the conventional ones (US Patent No ). To accommodate the need in sampling acids and alkaline aerosols commonly seen in the field, the development of personal denuder for simultaneous separate and size-selective sampling of gaseous and aerosol phases of acidic acids and bases has been achieved 52, 53). A new triple filter system has also been developed to simultaneously separate and collect the vaporous and aerosol phases of toluene diisocyanate exposed in spray painting and polyurethane foam manufacturing operations 54). Other studies examining the effects of environmental conditions and electrical charges on the weighing accuracy of different filter materials, the performance of commercial aerosol number samplers and direct reading aerosol monitors, and the error due to masking effect in fiber counting and bio-aerosol colony counting have also been conducted 55 60). These invention and scientific findings in aerosol sampling shed light in the correct relationship between aerosol exposure and health effects. Conclusion Words Continuous modernization and industrialization engage in brand new and unknown hazards in the workplaces. On top of several thorough reviews relating occupational medicine in Taiwan 61 63), this article tried to present an approach to integrating occupational health researches from a well organized collaboration from universities, industrial associations, labor unions, non-profit institutes, and governmental agencies to advantage multiple aspects in Taiwan. Similarly, to strengthen a multilateral collaboration on occupational health researches will be also beneficial to promote all workers well-being. These research experiences might provide some valuable experiences to other countries in the world. Acknowledgments This study was supported by the Institute of Occupational Safety and Health (IOSH) and Council of Labor Affairs (CLA). Reference 1) Statistical of National Income in Taiwan Area (2003) Directorate-General of Budget, Accounting & Statistics, Executive Yuan, Taiwan, Republic of China. 2) Labor Force Statistics (2003) Directorate-General of Budget, Accounting & Statistics, Executive Yuan, Taiwan, Republic of China. 3) Monthly Bulletin of Labor Statistics, No.131, Council of Labor Affairs, Executive Yuan, Taiwan, Republic of China. 4) Survey of Employees Perceptions of Safety and Health in the Work Environment in 2001 Taiwan (2002) Institute of Occupational Safety and Health (IOSH) ) Wang JD, Huang PH, Lin JM, Su SY, Wu MC (1988) Occupational asthma due to toluene diisocyanate among Velcro-like tape manufacturers. Am J Ind Med 14, ) Deng JF, Wang JD, Shih TS, Lan FL (1987) Outbreak of carbon tetrachloride poisoning in a color printing factory related to the use of isopropyl alcohol and an air conditioning system in Taiwan. Am J Ind Med 12, ) Wang JD, Lai MY, Chen JS, Lin JM, Chiang JR, Shiau SJ, Chang WS (1991) Dimethylformamide-induced liver damage among synthetic leather workers. Arch Environ Health 46, ) Du CL, Wang JD (1998) Increased morbidity odds ratio of primary liver cancer and cirrhosis of the liver among vinyl chloride monomer workers. Occup Environ Med 55, ) Guo YL, Shiao JSC, Chuang YC, Huang KY (1999) Needlestick and sharp injuries among health care workers in Taiwan. Epidemiol Infect 122, ) Wang JD, Chang YC, Kao KP, Huang CC, Lin CC, Yeh WY (1986) An outbreak of N-hexane induced polyneuropathy among press proofing workers in Taipei. Am J Ind Med 10, ) Wang JD, Huang CC, Hwang YH, Chiang JR, Lin JM, Chen JS (1989) Manganese induced parkinsonism: an outbreak due to an unrepaired ventilation control system in a ferromanganese smelter. Br J Ind Med 46, Industrial Health 2004, 42,

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