• Journal of Preventive Medicine and Public Health
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• v.26 no.2 s.42
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• pp.210-221
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• 1993

In order to evaluate the confounding factors of neurobehavioral tests and the neurobehavioral effects in the workers exposed to organic solvents, NCTB was carried out on 100 workers. 46 workers had never been exposed to neurotoxic substances, and the others were being exposed to the solvents, mainly toluene. Simple reaction time, digit symbol, Santa Ana dexterity test and persuit aiming were different with age in non exposure group. Simple reaction time was carried out well in males, and digit symbol and persuit aiming were in females. There was no difference at educational level when the subject was educated over 12 years. Santa Ana dexterity and Benton visual test differed according to exposure level to toluene, however simple reaction time didn't. The acute neurotoxic effect was not excluded in this study. But, NCTB could be used to evaluate and prevent neurobehavioral changes in workers exposed to neurotoxic solvents in Korea.

• Safety and Health at Work
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• v.4 no.3
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• pp.123-135
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• 2013

Exposure to manganese (Mn) is associated with neurobehavioral effects. There is disagreement on whether commonly occurring exposures in welding, ferroalloy, and other industrial processes produce neurologically significant neurobehavioral changes representing parkinsonism. A reviewof methodological issues in the human epidemiological literature onMnidentified: (1) studies focused on idiopathic Parkinson disease without considering manganism, a parkinsonian syndrome; (2) studies with healthy worker effect bias; (3) studies with problematic statistical modeling; and (4) studies arising from case series derived from litigation. Investigations with adequate study design and exposure assessment revealed consistent neurobehavioral effects and attributable subclinical and clinical signs and symptoms of impairment. Twenty-eight studies show an exposure-response relationship between Mn and neurobehavioral effects, including 11 with continuous exposure metrics and six with three or four levels of contrasted exposure. The effects of sustained low-concentration exposures to Mn are consistent with the manifestations of early manganism, i.e., consistent with parkinsonism. This is compelling evidence thatMnis a neurotoxic chemical and there is good evidence that Mn exposures far below the current US standard of $5.0mg/m^3$ are causing impairment.

• Safety and Health at Work
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• v.9 no.4
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• pp.381-387
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• 2018

Background: Physician behaviors that undermine a culture of safety have gained increasing attention as health-care organizations strive to create a culture of safety and reduce medical errors. We developed, implemented, and assessed a course to teach physicians skills regarding effective coping and interpersonal communication skills and present our results regarding outcomes. Methods: We examined a professional development program specifically designed to address unprofessional or distressed behaviors of physicians, and we evaluated the impact on burnout, quality of life, and emotional flooding scores of the physicians. Assessments of burnout, quality of life, and emotional flooding were assessed preintervention and postintervention. Results: Results demonstrated statistically significant reductions over time in physicians' emotional flooding and emotional exhaustion (EE). Specifically, using a Wilcoxon Signed-Rank test, results revealed that flooding scores at follow-up were statistically significantly lower than at baseline, V = 590, p < 0.05, and EE and personal accomplishment distributions were found to significantly deviate from normal as indicated by Shapiroe-Wilks tests (p < 0.05). A Wilcoxon signed-rank test indicated that EE scores were significantly higher at baseline compared to follow-up 1, V = 285, p < 0.05. Conclusion: We conclude that the physician participants who enrolled in the educational skills training program improved scores on emotional flooding and EE and that this may be indicative of improved skills related to their experiences and learning in the program. These improved skills in physicians may have a positive impact on the overall culture of safety in the health system setting.

• Journal of Environmental Health Sciences
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• v.33 no.5
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• pp.345-352
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• 2007

As mercury absorbed into body can cross the blood-brain barrier and react with DNA and RNA. Central nervous system has been known to be affected especially in children. But it was very difficult to know the influences of chronic low-does Hg exposure on the health. Although many studies investigated the affect, most of results were still disparate. In order to investigate the health effects of mercury exposure, several test were conducted for some Korean school children. The general health effects were investigated using blood test, Posturography and computer-based neurobehavioral test was done to examine the affect of Hg into neural responses. About 400 children were chosen for blood test whose blood Hg level were upper and lower 10% of population participated in the nationwide Hg exposure survey. The concentration of calcium and creatine, the number of white and red blood cell showed statistical significance with Hg exposure in blood test. Another 36 children were selected from the same participants for the posturography and neurobehavioral test. The intensity and center frequency of hand tremor which were related to unconsciousness also showed distinct significances. Any general relations with Hg exposure were not found in all test including computer-based neurobehavioral test.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.2
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• pp.116-122
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• 2011

Human occupational exposure to n-hexane has been associated with neurobehavioral symptoms such as depression, irritablity, acute irritation symptom, concentration disturbance and fatigue. Effects of monoamine oxidase (MAO) B and serotonin transporter receptor (5-HTTR) polymorphisms on the neurobehavioral symptoms were investigated in 70 male workers from TV and computer monitor manufacturing plants exposed to n-hexane. Neurobehavioral symptoms were assessed through a self-reported questionnaire and ambient level of n-hexane was measured by NIOSH method. Blood and urine were collected from each workers to determine the MAO(B), 5-HTTR and urinary 2,5-hexanedione(2,5-HD). The mean concentration of volatile n-hexane was $18.8{\pm}28.8ppm$ and that of urinary 2,5-HD was $1.07{\pm}1.47mg/g$ creatinine. Statistically significant associations with sexual disturbance were age and smoking. The frequencies of MAO(B) AA, AG and GG were 18.6%, 45.7% and 35.7%, respectively, and the frequencies of 5-HTTR ll, ls and ss genotype were 82.9%, 15.7% and 1.4%, respectively. MAO (B) gene polymorphisms had susceptibility to the neurobehavioral symptoms such as fatigue, concentration disturbance, irritability and acute irritation symptom and 5-HTTR gene polymorphism had susceptibility to the sleep disturbance and acute irritation symptom. On multiple logistic regression analysis for the neurobehavioral symptoms, memory disturbance was significantly associated with smoking(OR=6.752, 95% CI=37.46) and drinking(OR=4.033, 95% CI=1.252-12.98), emotional lability was MAO(B) genotype(OR=0.412, 95% CI=0.170-0.996), fatigue (OR=1.011, 95% CI=1.000-1.021) and acute irritation(OR=0.990, 95% CI=0.981-1.000) were working duration and sexual disturbance were significantly associated with age(OR=1.208, 95% CI=1.042-1.399), ambient n-hexane(OR=1.077, 95% CI=1.005-1.154) and 2,5-HD(OR=0.186, 95% CI=0.041-0.841). This finding implies that the MAO (B) and 5-HTTR polymorphisms may affect susceptibility for specific neurobehavioral symptoms associated with n-hexane exposure in workers.

• Toxicological Research
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• v.16 no.2
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• pp.117-124
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• 2000

The objective of this experiment is to investigate neurobehavioral and developmental effects of fumonisin B1 (FB1) after prenatal FB1 administration in rats. FB1 (0.8 or 1.6 mg/kg) was orally exposed to pregnant rats during gestational days 13 to 20, whereas the vehicle alone was administered to control group. Maternal and offspring body weights, physical landmarks of incisor eruption, eye opening, testes descending and vaginal opening, open field activity, running wheel activity, and complex maze performance were included as endpoints for developmental and neurobehavioral measurement. Maternal body weights were not signfficantly altered after FB1 exposure. Percentage of maternal weight gain difference between control and 1.6 mg/kg FBI groups was about 4%. Pre- and post-weanling weight of offsprings after prenatal exposure to FB1 was not signfficantly changed, suggesting that FB1 at 0.8 or 1.6 kg/kg doses may not cross the placenta. Significant gender difference in running wheel activity on postnatal days 57 to 63 and complex maze performance on postnatal days 75 to 78 was observed.

• Safety and Health at Work
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• v.15 no.1
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• pp.9-16
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• 2024

Background: E-waste workers in Hong Kong are handling an unprecedented amount of e-waste, which contains various neurotoxic chemicals. However, no study has been conducted to evaluate the neurological health status of e-waste workers in Hong Kong. This study aimed to evaluate the prevalence of neurobehavioral alterations and to identify the vulnerable groups among Hong Kong e-waste workers. Methods: We recruited 109 Hong Kong e-waste workers from June 2021 to September 2022. Participants completed standard questionnaires and wore a GENEActiv accelerometer for seven days. Pittsburgh Sleep Quality Index and Questionnaire 16/18 (Q16/18) were used to assess subjective neurobehavioral alterations. The GENEActiv data generated objective sleep and circadian rhythm variables. Workers were grouped based on job designation and entity type according to the presumed hazardous level. Unconditional logistic regression models measured the associations of occupational characteristics with neurobehavioral alterations after adjusting for confounders. Results: While dismantlers/repairers and the workers in entities not funded by the government were more likely to suffer from neurotoxic symptoms in Q18 (adjusted odds ratio: 3.18 [1.18-9.39] and 2.77 [1.10-7.46], respectively), the workers from self-sustained recycling facilities also have poor performances in circadian rhythm. Results also showed that the dismantlers/repairers working in entities not funded by the government had the highest risk of neurotoxic symptoms compared to the lowest-risk group (i.e., workers in government-funded companies with other job designations). Conclusion: This timely and valuable study emphasizes the importance of improving the working conditions for high-risk e-waste workers, especially the dismantlers or repairers working in facilities not funded by the government.

• Korean Journal of Psychosomatic Medicine
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• v.2 no.1
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• pp.46-51
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• 1994

Model' is one of the well-used, but poorly understood word in the neurobehavioral research. After Darwin's evolutionary theory, it has been generally believed that human is different from animals in terms of the complexity, not of the essential. This notion could be applied to the mind as well as body. Therefore, it became possible to establish animal models in the scientific field of mind. Experimental analysis of the animal behavior becomes an important area for establishing an animal model of human psychopathology because behavior is the ambassador of the mind. A model emphasizes a structural correspondence between sets of causally related variables in two different domains such as the animal and the human. The first selection of elements of the two domains in correspondence called the initial analogy. Once the initial analogy is formed. causally related variables in the two domains are examined and arrayed The structural parallel is the formal analogy of a model, and similarities between corresponding variables are called material analogy. Models may serve any of three major functions ; heuristic, evidential and representative. In many cases, utilizing models may be more practical than directly assessing the domain of primary interest, since technical and/or ethical problems are more serious in the human domain. Although modeling is important to study human psychopathology, rare animal models approved to be a good model for the human psychopathology up to now. Developing the appropriate model is urgent to solve many problems raised from human psychopathology.

• Environmental Analysis Health and Toxicology
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• v.28
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• pp.15.1-15.8
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• 2013

Objectives The aim of this study was to determine the association between low-level mercury exposure and neurobehavioral functions in adults living in coastal regions of Korea. Methods We selected 172 adults aged 20-65 years living in a city in the coastal region of Korea. A sociodemographic survey was conducted, mercury levels in the blood, urine, and hair were measured, and the associations according to computerized neurobehavioral tests were determined using univariate analysis. After adjustment for associated variables, a multivariate linear regression analysis was performed. Results The geometric mean mercury levels in the blood, urine, and hair were $5.41{\mu}g/L$ (range, $0.00-15.84{\mu}g/L$), $1.17{\mu}g/g$-creatinine (range, $0.00-32.86{\mu}g/g$-creatinine), and 1.37 mg/kg (range, 0.42-6.56 mg/kg), respectively. Variables that were associated with simple reaction time according to the neurobehavioral test results were age and urine mercury level. Variables associated with choice reaction time were the recent use of Korean traditional medicine and urine mercury level. Variables associated with the right-hand finger tapping speed test were age, gender, smoking behavior, education level, monthly household income, and urine mercury level. Variables associated with the left-hand finger tapping speed test were age, gender, education level, and urine mercury level. After adjustment for associated variables, there was no significant association between urine mercury level and simple reaction time (${\beta}=25.96$; p =0.47), choice reaction time (${\beta}=50.37$; p =0.32), or the number of left-hand finger taps (${\beta}=-1.54$; p =0.21). However, urine mercury level was significantly associated with the number of right-hand finger taps (${\beta}=-3.86$; p =0.01). Conclusions We found no evidence that low-level mercury exposure in adults is associated with deficits in neurobehavioral functions. A longer follow-up study is required to confirm this conclusion.

• Journal of Environmental Health Sciences
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• v.41 no.4
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• pp.268-276
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• 2015

Objectives: According to the 2007 Korea National Environmental Health Survey (KNEHS), some areas in the Gyeongsang Provinces showed very high blood mercury levels in adults. We conducted this project to investigate any related health effects in children due to mercury levels in these areas. Methods: In total, 1,097 students between grades 3 and 6 at 19 elementary schools were recruited from four areas with high mercury exposure as identified by the KNEHS. Total mercury levels in biological samples were compared with health check-ups performed on the schoolchildren. Biological monitoring, supported by questionnaires, a computerized neurobehavioral test, a posturography test and a personality test, were applied. Results: Triglycerides showed a significant relation with mercury in blood, urine and hair. Total mercury concentrations were divided into two groups: upper and lower concentration groups based on the median value. In the computerized neurobehavioral test, the upper blood mercury group showed a greater reaction time for color-word vigilance (p<0.05). In the posturography test, the intensity value of the tremor test showd high significant relations with mercury levels (p<0.01). In the personality test, self-consciousness, misdeeds and family relationships showed significant differences between the upper and lower urine mercury groups (p<0.01), and specific reactions, ego resilience and hyperactivity also showed some differences (p<0.1). Conclusion: Some items in the neurobehavioral test, posturography test and personality test showed significant relations with biological mercury levels. Therefore, monitoring and appropriate management of students showing high mercury levels are recommended in order to reduce their mercury exposure.