ABSTRACT
Background The presence of formaldehyde, ammonia, benzene, toluene, and xylene in indoor air of public places has been confirmed to cause health damage. The employees of barber and beauty shops are exposed to relatively enclosed space for a long time, and could surfer more serious health risks from indoor air chemical pollutants. Objective To analyze the concentrations of common indoor air chemical pollutants in barber shops and beauty salons in Liaocheng City, and explore potential health risks of the pollutants for employees. Methods Using a stratified randomized sampling method, 8 to 10 barber shops and 5 to 10 beauty salons were selected in the main urban area of Liaocheng City to conduct monitoring of the sanitary conditions of public places in winter and summer every year from 2016 to 2021; the indoor air concentrations of formaldehyde, ammonia, benzene, toluene, and xylene in the selected sites were measured, and a questionnaire survey was conducted to collect exposure characteristics of indoor pollutants. The concentration distributions of the five chemical pollutants were obtained from the monitoring data for 6 consecutive years, and the health risk assessment model recommended by the U.S. Environmental Protection Agency was used to perform health risk assessment of inhalation exposure. Results In 2016–2021, the median indoor air concentrations of formaldehyde, ammonia, benzene, toluene, and xylene in the two types of sites were lower than the limits of Hygienic Indicators and Limits for Public Places (GB 37488-2019), but the concentrations of some monitoring sites were higher than the limits. The disqualification rates of the five pollutants in the barber shops were 16.8%, 2.7%, 2.4%, 6.4%, and 12.0%, respectively. The disqualification rate of formaldehyde was the highest in all pollutants (22.0%), while the disqualification rates of ammonia, toluene, and xylene were 1.3%, 2.0%, and 2.0% in beauty salons respectively. Both formaldehyde and benzene were found to have carcinogenic risks (CR) in the two types of public places. Both median values of CR were greater than 1.0×10−6, and both maximum values were greater than 1.0×10−4. Formaldehyde had the highest non-carcinogenic risk in the indoor air of barber shops and beauty salons. The median non-carcinogenic hazard quotients (HQ) of formaldehyde were both greater than 1, and the maximum values were 16.72 and 12.19 times of the standard value; ammonia and toluene had the lowest non-carcinogenic risks, and their maximum values of HQ were less than 1; the median HQs of benzene and xylene were far less than 1, but their maximum risk values of barber shop were greater than 1. Conclusion For the sake of worker's health, formaldehyde and benzene should be the indoor air pollutant control priority for barber shops and beauty salons in Liaocheng; formaldehyde poses the most serious health hazard to practitioners and should be given high attention and necessary measures to reduce the hazard; benzene poses certain carcinogenic risks, with some of its highest values exceeding 10−4, which is higher than the recommended safety threshold.
ABSTRACT
<p><b>OBJECTIVE</b>Risk assessment and risk control for occupational exposure to chemical toxicants were performed on an isophorone nitrile device with an annual production of 5,000 tons, based on improved Singaporean semi-quantitative risk assessment method, with consideration of actual situation in China and in the present project.</p><p><b>METHODS</b>With the use of engineering analysis and identification of occupational hazards in the improved Singaporean semi-quantitative risk assessment method, hazard rating (HR) and risk assessment were performed on chemical toxicants from an isophorone nitrile device with an annual production of 5,000 tons.</p><p><b>RESULTS</b>The chemical toxicants in the isophorone nitrile device were mainly isophorone, hydrocyanic acid, methanol, phosphoric acid, sodium hydroxide, and sodium cyanide; the HR values were mild hazard (2), extreme hazard (5), mild hazard (2), mild hazard (2), moderate hazard (3), and extreme hazard (5), respectively, and the corresponding exposure rating (ER) values were 2.09, 2.72, 2.76, 1.68, 2.0, and 1.59, respectively. The risk of chemical toxicants in this project was assessed according to the formula Risk = [HR×ER](1/2). Hydrocyanic acid was determined as high risk, sodium hydroxide and sodium cyanide as medium risk, and isophorone, methanol, and phosphoric acid as low risk. Priority in handling of risks was determined by risk rating. The table of risk control measure was established for pre-assessment of occupational hazards.</p><p><b>CONCLUSION</b>With risk assessment in this study, we concluded that the isophorone nitrile device with 5,000 ton annual production was a high-occupational hazard device. This device is a project of extreme occupational hazard. The improved Singaporean semi-quantitative risk assessment method is a scientific and applicable method, and is especially suitable for pre-evaluation of on-site project with no analogy.</p>
Subject(s)
Humans , Cyclohexanones , Nitriles , Occupational Exposure , Risk AssessmentABSTRACT
The primary importance of magnetic resonance (MR) imaging in evaluating anal fistulas lies in its ability to demonstrate hidden areas of sepsis and secondary extensions in patients with fistula in ano. MR imaging is relatively expensive, so there are many healthcare systems worldwide where access to MR imaging remains restricted. Until recently, computed tomography (CT) has played a limited role in imaging fistula in ano, largely owing to its poor resolution of soft tissue. In this article, the different imaging features of the CT and MRI are compared to demonstrate the relative accuracy of CT fistulography for the preoperative assessment of fistula in ano. CT fistulography and MR imaging have their own advantages for preoperative evaluation of perianal fistula, and can be applied to complement one another when necessary.