Seong Kyu Kang

Development of the Behavioral Assessment and Research System (BARS) to detect and characterize neurotoxicity in humans

The Behavioral Assessment and Research System (BARS) is a computer-based testing system designed to assess neurobehavioral function in humans. It was developed to provide a series or battery of neurobehavioral tests optimized for the detection of neurotoxicity in non-mainstream human populations, specifically people with limited education or literacy. Key to meeting this goal were simply-stated instructions divided into an elemental series of steps, a 9BUTTON response unit to replace the computer keyboard for responding, and spoken instructions. Modifications all underwent serial testing in target populations to successively hone the changes to be more effective. A similar process was followed when developing adjustable parameters, test reliability assessments, and when implementing these tests with populations from different cultural groups and children. The principles and experiences that guided the development of BARS should inform the development of future testing systems to ensure that the new tests can be used with non-mainstream populations, which may be increasingly subject to neurotoxic exposures.

Occupational Diseases in Korea

Korea has industrialized since the 1970s. Pneumoconiosis in coal miners was the most common occupational disease in the 1970s to 1980s. With the industrialization, the use of many chemicals have increased since the 1970s. As a consequence, there were outbreaks of occupational diseases caused by poisonous chemicals, such as heavy metal poisoning, solvent poisoning and occupational asthma in the late 1980s and early 1990s with civil movement for democracy. Many actions have been taken for prevention by the government, employers and employees or unions. In the 1990s most chemical related diseases and pneumoconiosis have rapidly decreased due to improving work environment. In the late 1990s, cerebro-cardiovascular diseases related to job stress or work overloads have abruptly increased especially after the economic crisis in 1998. After the year 2000, musculoskeletal disorders became a major problem especially in assembly lines in the manufacturing industry and they were expanded to the service industry. Mental diseases related to job stress have increased. Infectious diseases increased in health care workers and afforestation workers. Occupational cancers are increasing because of their long latency, although the use of carcinogenic substances are reduced, limited, and even banned.

Historical review of the List of Occupational Diseases recommended by the International Labour organization (ILO).

The list of occupational diseases established in the international and national legal system has played important roles in both prevention of and compensation for workers’ diseases. This report reviewed the historical development in the ILO list of occupational diseases and suggested implications of the trends. Since the first establishment of the ILO list of occupational diseases in 1925, the list has played a key role in harmonizing the development of policies on occupational diseases at the international level. The three occupational diseases (anthrax, lead poisoning, and mercury poisoning) in the first ILO list of occupational diseases, set up in 1925 as workmen’s compensation convention represented an increase of occupational diseases from the Industrial Revolution. Until the 1960s, 10 occupational diseases had been representative compensable occupational diseases listed in Convention No. 121, which implies that occupational diseases in this era were equated to industrial poisoning. Since 1980, with advancements in diagnostic techniques and medical science, noise-induced hearing loss, and several bronchopulmonary diseases have been incorporated into the ILO occupational list. Since 2002, changes in the structure of industries, emerging new chemicals, and advanced national worker’s compensation schemes have provoked the ILO to revise the occupational disease list. A new format of ILO list appended in Recommendation 194 (R194) was composed of two dimensions (causes and diseases) and subcategories. Among 50 member states that had provided their national lists of occupational diseases, until 2012 thirty countries were found to have the list occupational diseases having similar structure to ILO list in R194.

Neurobehavioral performance in workers exposed to toluene

Toluene is widely used in adhesive, printing, painting and petroleum industries in many countries. This study was conducted to examine the effect of chronic exposure to toluene below 100ppm on neurobehavioral performance using a computerized neurobehavioral test battery that emphasizes simple instructions and practice prior to testing. The Behavioral Assessment and Research System (BARS) with Korean language instructions was administered to 54 workers from three different industries: oil refinery, gravure printing, and rubber boat manufacturing. The battery consisted of the following tests: Digit Span (DS), Simple Reaction Time (SRT), Selective Attention (SAT), Finger Tapping (FT), and Symbol Digit (SD). Urine was collected at the end-of-shift to analyze urinary hippuric acid to assess exposure level to toluene. Based on the previous air toluene level, workers were divided into three groups: Low (21 workers, less than 10ppm), Moderate (13 workers, 20-30ppm) and High (20 workers, 70-80ppm) exposure status. Analysis of Covariance (ANCOVA) adjusting for age, education and work duration as covariates, was performed to examine the relationship between the neurobehavioral performance and the exposure groups. Poorer performance of the High exposure group was found on FT-preferred (F=7.034, p=0.002) and SAT latency (F=11.710, p=0.000). Age showed a significant correlation with SD (r=0.417, p=0.002) and SAT number correct (r=-0.460, p=0.000). Years of education and work duration were not significantly correlated with any items. This study supports that toluene exposure below 100ppm is associated with neurobehavioral changes and that high-level toluene exposure could cause not only attention and concentration, but also motor performance deficits.

Ionizing Radiation-induced Diseases in Korea

Radiation risk has become well known through epidemiological studies of clinically or occupationally exposed populations, animal experiments, and in vitro studies; however, the study of radiation related or induced disease has been limited in Korea. This study is to find the level of occupational radiation exposure for various kinds of accidents, compensated occupational diseases, related studies, and estimations on future occupational disease risks. Research data of related institutions were additionally investigated. About 67% of 62,553 radiation workers had no exposure or less than 1.2 mSv per year. The 5 reported cases on radiation accident patients in Korea occurred during nondestructive testing. According to the recent rapid increase in the number of workers exposed to radiation, a higher social recognition of cancer, and an increasing cancer mortality rate, it is expected that occupational disease compensation will rapidly increase as well. Therefore, it is important to develop scientific and objective decision methods, such as probability of causation and screening dose in the establishment of an exposure and health surveillance system.