Correlation analysis and benchmark dose study on bone metabolic biochemical index of low doses of exposed hydrogen fluoride workers / 中华劳动卫生职业病杂志

Objective: To analyze correlation of occupational hydrogen fluoride exposure to low doses of bone metabolism index through occupational epidemiological investigation and benchmark dose calculation. Methods: In May 2021, using cluster sampling method, 237 workers exposed to hydrogen fluoride in a company were selected as the contact group, and 83 workers not exposed to hydrogen fluoride in an electronics production company were selected as the control group. The external exposure dose and urinary fluoride concentration, blood and urine biochemical indicators of the workers was measured.The relationship between external dose and internal dose of hydrogen fluoride was analyzed. The external dose, urinary fluoride was used as exposure biomarkers, while serum osteocalcin (BGP), serum alkaline phosphatase (AKP) and urinary hydroxyproline (HYP) were used as effect biomarkers for bone metabolism of hydrogen fluoride exposure. The benchmark dose calculation software (BMDS1.3.2) was used to calculate benchmark dose (BMD) . Results: Urine fluoride concentration in the contact group was correlated with creatinine-adjusted urine fluoride concentration (r=0.69, P=0.001). There was no significant correlation between the external dose of hydrogen fluoride and urine fluoride in the contact group (r=0.03, P=0.132). The concentrations of urine fluoride in the contact group and the control group were (0.81±0.61) and (0.45±0.14) mg/L, respectively, and the difference between the two groups was statistically significant (t=5.01, P=0.025). Using BGP, AKP and HYP as effect indexes, the urinary BMDL-05 values were 1.28, 1.47 and 1.08 mg/L, respectively. Conclusion: Urinary fluoride can sensitively reflect the changes in the effect indexes of biochemical indexes of bone metabolism. BGP and HYP can be used as early sensitive effect indexes of occupational hydrogen fluoride exposure.

Study on the diffusion of hydrogen fluoride in an electrolytic fluoride plant based on CFD numerical simulation method / 中华劳动卫生职业病杂志

Objective: Using CFD technology to grasp the distribution and diffusion of hydrogen fluoride in an electrolytic fluorine plant, provide guidance and scientific basis for enterprises to carry out occupational health management in enterprises, install hazardous substance alarm devices, and protect workers' occupational health. Methods: In July 2019, the diffusion law of hydrogen fluoride gas produced in an electrolytic fluorine plant is selected as the research object. Through the establishment of models and grids, the Fluent numerical simulation method is finally used to simulate the diffusion and distribution of hydrogen fluoride gas under ventilation conditions. Results: The results showed that the average concentration of hydrogen fluoride was 0.045 mg/m(3) in the workplace, and the absorbed zone height (1.5 m) was 0.02 mg/m(3) in the inspection channel, which was in accordance with the national standard. However, there is eddy current above the electrolyzer near the inlet, may lead to the accumulation of hydrogen fluoride gas. Conclusion: The research of CFD numerical simulation method on the distribution and diffusion of hydrogen fluoride concentration in electrolytic fluorine plant can be applied to the prevention, control and management of occupational hazards in electrolytic fluorine plant.

Quemadura química por ácido fluorhídrico: mecanismos fisiopatológicos de la lesión / Hydrofluoric acid burn: pathophysiological mechanisms of injury / Queimadura química por ácido fluorídrico: mecanismos fisiopatológicos da lesão

Resumen: Las quemaduras por exposición a químicos son una forma de lesión poco frecuente; sin embargo, los efectos secundarios se pueden considerar catastróficos a corto, mediano y largo plazo. El ácido fluorhídrico es una sustancia química perteneciente a los ácidos, tiene aplicación industrial y doméstica, y se encuentra en diferentes concentraciones. El fluoruro de hidrógeno está formado por un ion hidrógeno y un ion fluoruro, que al entrar en contacto con el agua adquiere su estado ácido, característica que le confiere mayor lesión de tejidos al entrar en contacto con ellos. Reportes describen lesiones de 1% de superficie corporal quemada, en una concentración al 50% capaz de generar toxicidad local y sistémica, que deriva en la muerte en cuestión de horas si no recibe un manejo oportuno encaminado a frenar el mecanismo de lesión, el cual se asocia a disminución de electrolitos calcio y magnesio, así como elevación de potasio, no sin dejar de lado la lesión corrosiva a nivel local que condiciona la aparición de necrosis licuefactiva. El objetivo de este trabajo es dar a conocer al personal médico y paramédico el mecanismo de lesión del ácido fluorhídrico, sus implicaciones clínicas y las alternativas terapéuticas.

Abstract: Chemical exposure burns are a rare form of injury; however, side effects can be considered catastrophic, in the short, medium and long term. Hydrofluoric acid is a chemical substance belonging to acids, it has industrial and domestic application, being in different concentrations. Hydrogen fluoride is made up of a hydrogen ion and a fluoride ion, which, when in contact with water, acquires its acid state, a characteristic that it acquires gives it greater tissue damage when in contact with them. Literary reports described injuries of 1% of the burned body surface, in a concentration of 50% capable of generating local and systemic toxicity, which leads to death in a matter of hours, if the patient does not receive timely management aimed at stopping the mechanism of injury. which is associated with a decrease in calcium and magnesium electrolytes, as well as an increase in potassium, not without neglecting the corrosive lesion at the local level that conditions the appearance of liquefactive necrosis. The objective of this work is to make known to the personal physician and paramedic the mechanism of injury of hydrofluoric acid, its clinical implications and the therapeutic alternatives.

Resumo: As queimaduras por exposição química são uma forma rara de lesão, porém, os efeitos secundários podem ser considerados catastróficos, a curto, médio e longo prazo. O ácido fluorídrico é uma substância química pertencente aos ácidos, possui aplicação industrial e doméstica, sendo encontrado em diferentes concentrações. O fluoreto de hidrogênio é formado por um íon hidrogênio e um íon fluoreto, que quando em contato com a água adquire seu estado ácido, característica que lhe confere maior dano tecidual quando em contato com eles. Relatos literários descrevem lesões de 1% da superfície corporal queimada, em concentração de 50% capaz de gerar toxicidade local e sistêmica, que leva à morte em questão de horas, se não receber tratamento oportuno visando coibir o mecanismo da lesão que está associada a uma diminuição dos eletrólitos de cálcio e magnésio, bem como a um aumento de potássio, não sem deixar de lado a lesão corrosiva a nível local que condiciona o aparecimento de necrose liquefativa. O objetivo deste trabalho é informar o pessoal médico e paramédico sobre o mecanismo de lesão causada pelo ácido fluorídrico, suas implicações clínicas e alternativas terapêuticas.

Psychometric properties of the 10-item Conner-Davidson resilience scale on toxic chemical-exposed workers in South Korea

BACKGROUND: Resilient individuals have a comprehensive ability to adapt to various life circumstances. Psychological resilience predicts an individual’s physiological response to stress. The 10-item Connor-Davidson Resilience Scale (CD-RISC) is a widely used measure to quantify the level of self-perceived resilience. This study examined the psychometric properties of a Korean version of the 10-item Connor-Davidson Resilience Scale (10-item K-CD-RISC) on workers in Gumi, South Korea, exposed to hydrofluoric acid (HF). METHODS: The questionnaires included the 10-item K-CD-RISC and Beck Anxiety Inventor (BAI), the Impact of Event Scale-Revised-Korean version (IES-R-K), the Rosen-berg Self Esteem Scale (RSES), the Center for Epidemiologic Studies-Depression Scale (CES-D), and the Perceived Stress Scale (PSS). These were randomly distributed at 237 workplaces near the HF-spill site, in the Gumi 4 complex. The responses of 991 (67.3%) workers were analyzed. RESULTS: The exploratory factor analysis shown that a single-factor model was consistent with the original design of the 10-item CD-RISC. The scale also demonstrated good internal consistency (Cronbach’s alpha = 0.95). Scores on the scale reflected different levels of resilience with respect to personal factors (age, gender, marital status, and education and income levels) that are thought to be differentiated. Differences of resilience were also reflected by psychiatric symptoms (anxiety and depression). Moreover, the total score of scale positively correlated with RSES, whereas the IES-R-K, BAI, CES-D, and the PSS negatively correlated with the 10-item K-CD-RISC. CONCLUSIONS: The 10-item K-CD-RISC has good psychometric properties and is applicable for victims exposed to noxious chemical such as HF.

Psychological effects of a disastrous hydrogen fluoride spillage on the local community

BACKGROUND: On September 27, 2012, at 3:43 pm, a hydrogen fluoride spill occurred in a manufacturing plant located at the 4th complex of the Gumi National Industrial Complex in Gumi City, South Korea. The present study aimed to evaluate the psychological effects of the hydrogen fluoride spill on the members of the community and to investigate their relationships with physical symptoms and changes in psychological effects occurring as time passed after the accident. METHODS: The 1st phase involved a survey of 1359 individuals that was conducted 1 month after the spill, and the 2nd phase involved a survey of 711 individuals that was conducted 7 months after the accident. The questionnaires included items for assessing demographic characteristics, hydrogen fluoride exposure level, physical symptoms, and psychological status. Physical symptoms were assessed to determine the persistence of irritations. Psychological status was assessed to investigate the impact of event level using the Impact of Event Scale – Revised Korean version (IES-R-K), and the anxiety level was assessed using the Beck Anxiety Inventory (BAI). RESULTS: As the hydrogen fluoride exposure level increased, the impact of event and anxiety levels increased significantly both 1 and 7 months after the accident (p < 0.05). The mean score of the impact of event levels decreased significantly from 33.33 ± 14.64 at 1 month after the accident to 28.68 ± 11.80 at 7 months after the accident (p < 0.05). The mean score of the anxiety levels increased significantly from 5.16 ± 6.59 at 1 month after the accident to 6.79 ± 8.41 at 7 months after the accident (p < 0.05). The risk of persistent physical symptoms at 7 months after the accident was significantly higher in females. The risk of persistent physical symptoms also increased significantly, with increasing age, hydrogen fluoride exposure, and impact of event levels (p < 0.05). CONCLUSIONS: The present study found that the impact of event level and anxiety level increased with increasing hydrogen fluoride exposure. Anxiety levels persisted even after time passed. The risk of persistent physical symptoms at 7 months after the accident was higher in females, and it increased with increasing age, hydrogen fluoride exposure level, and impact of event levels.

Assessment of an accident of small amount uranium hexafluoride gas leakage on the influence of human health / 中国职业医学

OBJECTIVE: To estimate the amount of the uranium hexafluoride( UF_6) gas leakage in a nuclear fuel element production line,and assess the effect of the leakage on human health. METHODS: The hypothetical accident model was set that the leakage of UF_6 was caused by the hose breakage between valve and pipeline in the UF_6 vaporization process. It took8 seconds for the aerosol to get to the staffs and the staffs needed 1-4 minutes to evacuate. The leakage amount of UF_6 gas and intake of uranium and hydrogen fluoride( HF) were calculated using the estimation formula of gas leakage and internal radiation dose. Its influence on human health was assessed. The radiation hazard and kidney damage induced by the UF_6 exposure,and the chemical hazards to human health caused by HF inhalation were assessed. RESULTS: It is supposed that the staffs need 1 minute to evacuate,the leakage amount of UF_6 within 1 minute is 88. 20 g,and the uranium content is about 59. 64 g. The committed effective dose of internal exposure is 0. 40 mSv. The predicted intake of uranium is4. 57 mg. The average inhalation concentration of HF is calculated to be about 90. 33 mg /m~3,which is below the promptly life-threatening or health-threatening acute concentration( 136. 93 mg /m~3). In this case,it has little impact on human health. If the staffs need 2-4 minutes to evacuate,the leakage amount of UF_6 within 1 minute is 176. 40-352. 80 g,and the uranium content is about 119. 27-238. 54 g,the committed effective dose of internal exposure is 0. 81-1. 62 mSv. In that case,it has a small radiation hazard caused by UF_6. However,the predicted intake of uranium is 9. 26-18. 51 mg,which might lead to a short-term kidney damage. If the evacuation time is 2,3 or 4 minutes,the average inhaled mass concentrations of HF are 83. 98,82. 03 and 81. 03 mg /m~3,respectively,which are close to or higher than the immediately dangerous to life or health concentration( 96. 82,79. 06 and 68. 46 mg /m~3,respectively),and it might lead to an acute HF poisoning,even sudden death. CONCLUSION: When the UF_6 leakage accident happens,the staffs should evacuate in 1minute. If the evacuation time is longer than 2 minutes,it will increase the risk of kidney damage,acute HF poisoning and sudden death.

A study on occupational hydrofluoric acid burns in a hydrofluoric acid manufacturing factory / 예방의학회지

Hydrofluoric acid is one of the strongest irritating, corrosive and poisonous inorganic chemicals. Hydrofluoric acid burns are occurring with ever-increasing frequency due to the wide use of this acid in industries. Hydrofluoric acid burns are characterized by severe progressive tissue destruction and excruciating pain due to the unique properties of the freely dissolvable fluoride ion. The authors reviewed medical records of 32 cases(36 spells) of hydrofluoric acid burns which occurred in a hydrofluoric acid manufacturing factory from Sep. 1, 1990 to June 30, 1993. The results are as follows; 1. Eleven measurements of air concentrations of hydrofluoric acid by detection tube method from 1990 to 1992 were all below TLV(Department of Labor, R. O. K). 2. There were 19 cases(22 spells) of hydrofluoric acid burns which occurred during the study period among regular employees. The overall incidence density of hydrofluoric acid was 17.8 cases(20.6 spells) per 100 person-year. Incidence density was 19.0 cases(22.0 spells) per 100 person-year among male workers and there were no female cases. Incidence density was 32.9 cases(38.3 spells) per 100 person-year among production workers and 1.9 cases(1.9 spells) per 100 person-years among management workers with the difference being statistically significant(P<0.01). 3. Of 32 cases(36 spells) of hydrofluoric acid burns among workers who were regularly employed or temporarily employed, 26 spells(81.2%) were between age 20 to 39. In 15 spells(41.7%) burns occurred between 12 : 00 and 17 : 59 with 16 spells(44.3%) having arrived at hospital within 2 hours after the accident. 4. Of 36 spells, the main cause of hydrofluoric acid burns were by splashes(8 spells, 22.2 %). The most frequent site of burns were fingers and pain was the most frequent symptom. Thirty spells(83.3%) of the hydrofluoric acid burns were treated with local injection of antidote(calcium gluconate). Complete recovery without scarring were observed in most of the cases(34 out of 36 cases, 94.4%). The study results suggest that to prevent hydrofluoric acid burns, environmental control and the wearing of hydrofluoric acid resistant protective clothes and gloves are important. It is also stressed that establishment of an emergency management and a transfer system for hydrofluoric acid burn victims is necessary.