Incidence of Dimethylacetamide Induced Toxic Liver Injury among Workers in a Synthetic Fiber Manufacturing Company / 대한산업의학회지

OBJECTIVES: The main goal of this study was to find the incidence of the dimethylacetamide (DMAc) induced toxic liver injury among workers who were exposed to DMAc for about 5 years in a synthetic fiber factory. METHODS: In our investigation, total 1,021 workers had been exposed to DMAc from 1st February, 2000 to 30th June, 2004. Among them, 24 workers who had initial abnormal hepatic enzyme level or was viral hepatitis B carrier were excluded. Finally, 997 DMAc exposed workers were followed up for their incidence of toxic liver injury. To find out DMAc induced toxic liver injury case, we carried out regular examinations including liver enzyme tests such as AST and ALT. RESULTS: We followed up 997 workers and among them 72 cases coincided with our case definition. Incidence density method was 6.05 per 100 person-year. and, a cumulative incidence by life table method was 0.0965 within a year. The incidence of the DMAc-induced toxic liver injury peaked at 4 to 5 in weeks after employment. There was no toxic liver injury case within second week after exposure to DMAc. Five new cases developed in 2th to 3th week, 25 cases in 4th to 5th week, 14 cases in 6th to 7th week, 12 cases in 8th to 9th week, 5 cases in 10th to 11th week, 4 cases in 12th to 13th week, 4 cases in 14th to 15th week, 1 case in 16th to 17th week, 1 case in 30th to 31th week, and there was one case in 48th to 49th week. CONCLUSIONS: The incidence rate of toxic liver injury was considerably high during the 1st year after a worker is placed. So it is needed to take careful monitoring of hepatic enzyme level for newly exposed worker.

Blood Lead Levels in Umbilical Cord and Neonatal Neurobehavioral Status / 대한산업의학회지

OBJECTIVES: To investigate the relation between umbilical cord blood lead level lower than 10 microgram/dl and neonatal neurobehavioral performance. METHODS: Umbilical cord blood lead level, as an indicator for prenatal exposure to lead, and Brazelton neonatal behavioral assessment scale (NBAS), as an indicator for effect, were determined in 86 neonates in Gumi, Kyungpook, Korea. The blood levels were measured by graphite furnace atomic absorption spectrophotometer. Development was assessed by NBAS at birth in 86 neonates and at 1 month in 55 neonates. RESULTS: The mean cord blood lead levels of the 86 and 55 neonates were 3.90 +/- 0.71 microgram/dl (range 2.24 - 5.39 microgram/dl) and 3.88 +/- 0.70 microgram/dl (range 2.24~5.03 microgram/dl), respectively. We used the median value of 4 microgram/dl to divide into low- and high- lead level groups. There was a significant difference in the peak of excitement at birth, and in the animate visual, inanimate visual, inanimate auditory, activity level, peak of excitement, and liability of states at one month, between the two groups. For cluster scores, motor system and state organization scores showed significant differences between the two groups. For adjusting the potential confounding effect of intial difference, differences of the scores between the two groups at one month were analysed with ANCOVA. The results of ANCOVA showed the significant difference between the two groups. CONCLUSIONS: The findings suggest that prenatal low-level lead exposure, even lower than 10 microgram/dl, might affect the neonatal neurobehavioral development.

Surveillance of Work-related Diseases in Kumi / 대한산업의학회지

OBJECTIVES: Area-based occupational disease surveillance in Kumi (KODS) was used to collect data on occupational diseases. The data was used to estimate the magnitude of the diseases, to analyze for their characteristics, and to find links for their intervention and prevention. METHODS: Since January 2001, occupational physicians and nurses in Occupational Health Service (OHS)have reported six major occupational diseases; occupational musculoskeletal disorders of the upper extremities(MSDUE), occupational dermatoses, toxic hepatitis, occupational asthma (OA), hand-arm vibration syndrome(HAVS), and occupational cancer. For the respective diseases, a reporting sheet and operational diagnostic criteria were developed by the KODS. An analysis of the KODS data, collected over a certain period, was compared with data from the Korea Labor Workers Corporation (KLWC) and the Specific Health Examination (SHE), and the incidence rates of the diseases estimated. RESULTS: Between Jan 2001 and Apr 2002, 287 cases of the six major occupational disease were reported. Of these, there were 132 (46.0%), 100 (34.8%), 34 (11.8%), 16 (5.6%), and 5 (1.7%), cases of MSDUE, occupational dermatoses, toxic hepatitis, OA, and HAVS, respectively. But, there were no cases of occupational cancer. 33 (11.5%) of the incidence were reported via the OHS, 206 (71.7%) from health checkups, and the other 48(16.8%) from other routes. The synthetic fibers and electronic components manufacturing industries accounted for the greatest number of reported cases. With respect to occupation, the greatest numbers of incidence were reported from the elementary occupations, textile workers, assemblers, and cooks and food services worker, in that order. Of the MSDUE cases, carpal tunnel syndrome and epicondylitis were the two most common diseases. Most of the occupational dermatoses were due to contact dermatitis, with organic solvents (59%), nickel (6%), and epoxy resin (5%) accounting for the majority of these cases. All cases of toxic hepatitis were induced by dimethylformamide or dimethylacetamide, which were reported by a unique monitoring system. During same period, there were no cases claimed by workers to the KLWC, and only three cases from SHE, were identified. Using data from workers' number and surveillance, the annual incidences of MSDUE, dermatoses, hepatitis, OA, and HAVS, per 100,000 workers were 63.6, 48.2, 17.9, 7.7, and 2.4, respectively. CONCLUSIONS: These results show that an area-based surveillance system can be very effective for the collection of data on work-related diseases, at least in Kumi.

Hand-Arm Vibration Syndrome and Neural Conduction Impairment in Swagging Workers Exposed to Hand-Arm Vibration / 대한산업의학회지

OBJECTIVES: To investigate the hand-arm vibration syndrome (HAVS) among symptomatic swagging workers exposed to hand-arm vibration, using medical evaluation and measurement of workplace vibration. Furthermore, to evaluate the neurophysiological METHODS: Four workers showing symptoms relevant to HAVS were evaluated. Medical evaluation consisted of medical interview, questionnaire, nail-bed compression test, and sensory perception tests for vibration and pain. Some other diseases were excluded by a medical interview, hematological assessment, and urinalysis. Cold provocation test was used to assess the peripheral vascular changes, and a nerve conduction velocity (NCV) test was implemented to ascertain the peripheral neural changes. Pegboard, hole plate, and tapping board tests were performed to assess motor nerve function. The hand-arm vibration acceleration levels of the swagging machines were measured. Six months later, follow-up NCV tests were performed. RESULTS: The actual exposure time to vibration was not longer than 15 minutes per day. The hand-arm vibration acceleration levels of the swagging machines, according to actual exposure time, were from 3.63 to 12.98 m/sec2, by ISO 5349. The vibratory perception thresholds and the recovery time of a nail color following finger cooling were significantly increased in all four workers. The perception of pain was mildly increased. The nerve conduction studies at first diagnosis and follow-up showed multifocal neural impairment caused by vibration. However, we could not rule out the concomitant presence of the carpal tunnel syndrome in one worker. CONCLUSIONS: These results show that HAVS can be caused by hand-arm vibration in swagging workers. Interestingly, the NCV results suggested that vibration-induced neural conduction impairments could vary, and need to be interpreted cautiously.

Three Cases of Skin Pigmentation Caused by 2,5-Hexanedione / 대한산업의학회지

OBJECTIVES: To report on the skin discoloration experienced by three workers handling 2 , 5 -hexanedione METHODS: Three workers, who showed orange-brown discoloration of the palms during observation under the Kumi occupational disease surveillance system, had their history evaluated and underwent physical examination. A workplace survey was performed by an occupational physician and an industrial hygienist. RESULTS: The three workers were determined to have been experiencing skin discoloration since the introduction of a new cleaning solvent. The new solvent contained 2,5-hexanedione, which is reported in the literature to be possibly capable of causing orangebrown discoloration of the skin. After discontinuation of solvent use, the workers recovered within a week. CONCLUSIONS: These cases demonstrate that 2,5-hexanedione can produce skin pigmentation.

Change of Visual Function and Lacrimation Among Male Near-Work Inspectors in a TV Manufacturing Plant / 대한산업의학회지

OBJECTIVES: The aim of this field-based longitudinal study was to investigate the effects of near-work on lacrimation and visual function, particularly refractive power. METHODS: Our study tracked sixty five male workers for about three years by means of ophthalmologic examinations and questionnaires, to collect data including eye symptoms and subjective work environmental factors. Ophthalmic examinations included visual acuity, Shirmer I test, and autorefractometry. In the first year, the inclusion criteria were ages less than 40 years, no history of ophthalmic diseases, emmetropia(-1.0

The Association of the Serum Magnesium with Hearing Loss Among Noise Exposed Male Workers / 대한산업의학회지

OBJECTIVES: This study was conducted to investigate that the chronic noise exposure is associated with decreased serum magnesium concentrations and evaluate whether decreased serum magnesium is associated with noise induced hearing loss. METHODS: One hundred seventy-eight male workers exposed to noise were selected and classified three groups by the degree of hearing loss. Hearing threshold levels were less than 30 dB at 1,000 Hz or less than 40 dB at 4,000 Hz in group I, more than 30 dB at 1,000 Hz or more than 40 dB at 4,000 Hz and 15 dB and less of pure tone average(PTA: (500 Hz+1,000 Hz+2,000 Hz)/3) in group II, more than 30 dB at 1,000 Hz or more than 40 dB at 4, 000 Hz and over 15 dB of PTA in group III. RESULTS: Serum magnesium concentrations were 2. 42+/-0. 26 nc/dt in group I, 2. 35+/-0.23 mg(dl in group II, 2.26+/-0.24 ne/dl in group III, respectively and significantly different between group I and group III (p<0. 01). It was negatively correlated with duration of the noise exposure as correlation coefficient(r) of -0.194 (p<0.05). Analysis of the multiple regression on hearing threshold levels showed that serum magnesium, diastolic blood pressure, duration of the noise exposure were statistically significant at 4,000 Hz(p<0.05). While only age was statistically significant at 1,000 Hz(p<0.05). CONCLUSIONS: These results suggest that chronic noise exposure may induces decrease in serum magnesium concentrations and that its decreased concentration is related with noise induced hearing loss.

A Case of Sparganosis Infesting in the Scrotum / 대한비뇨기과학회지

Sparganum is a parasite infesting principally in the cats or dogs, but human infestation was also not uncommonly reported. In Korea, the reported cases of sparganosis are over 70. We experienced a case of sparganosis in scrotum. This patient, 47 year-old man, had had episodes of intake raw snakes for 6 years as a tonic since 12 years before. The removed larvae of the parasite revealed milkish-white color, flat, and glistening appearance. Life cycle and route of infection of sparganum mansoni are discussed with review of the literatures.