Sara Karimi Zeverdegani

BACKGROUND: Nail salon technicians are susceptible to potential exposure to a diverse array of hazardous chemicals in the form of dust or vapors. One of the main routes of exposure is dermal contact. OBJECTIVE: The aim of present study was to health risk assessment of dermal exposure to dust containing heavy metals in nail salon technicians. METHODS: Dust sampling was done on the work surface of 20 available nail salon technicians. The concentration of five metals including cadmium, lead, chromium, nickel, and manganese were determined using ICP-MS. Afterwards, the United States Environmental Protection Agency (USEPA) guideline was used to estimate the potential health risks, including carcinogenic and non-carcinogenic risks, associated with the analyzed metals. RESULTS: Results indicated the mean concentrations of Pb, Cd, Ni, Cr and Mn were 0.7953±0.4373, 0.0952±0.0264, 0.7666±0.8629, 0.4900±0.5994 and 1.134±0.4736, respectively. The hazard quotient (HQ) of all metals was within the permissible value, while hazard index (HI) was greater than 1. The probability of cancer risk (CR) resulting from dermal exposure to Ni, Cd and Cr exceeded the acceptable risk levels (10-6–10–4), but CR calculated for Pb was less than allowable value. CONCLUSION: Implementation of engineering controls such as downdraft vented nail tables and portable source capture systems is necessary. Besides, the use of personal protective equipment such as disposable nitrile gloves, N95 respirator masks, and ensuring proper training on safe work practices is recommended.

Artificial Neural Networks (ANN) have great potential in toxicology research. They may be used to predict the toxicity of various chemical compounds or to classify compounds based on the toxic effects they have on the body or in the environment. Nowadays, numerous ANN models have been developed, some of which may be used to identify and possibly explain complex chemical-biological interactions in toxicological sciences. Tightly coupled multilayer perceptron’s may, under some conditions, have high classification accuracy and discrimination power in separating damaged from intact cells after exposure to a toxicant. Regularized and fully connected convolutional neural networks cannot detect and detect discrete changes in toxicity related two-dimensional data patterns. Bayesian neural networks with weight marginalization may sometimes have better prediction performance compared to traditional approaches. With the further development of artificial intelligence, artificial neural networks are expected to become an important part of various accurate and cost-effective biosensors for detecting various toxic substances and evaluating their biochemical properties in the future. In this brief review article, we discussed the recent researches focused on the scientific value of ANN in evaluating and predicting the toxicity of various chemical compounds and the challenges and limitations in the field of artificial intelligence and the use of artificial neural networks.

Background: Welding fumes (WFs) contain heavy metals that can induce oxidative stress and health issues in welders. This review investigated the relationship between oxidative stress biomarkers and trace metals in welders’ bodily fluids. Methods: Online databases such as Scopus, PubMed, Web of Science, Science Direct, EMBASE, and Google Scholar were reviewed, with a specific emphasis on the effects of metal fume exposure during welding. Specific keywords such as "welding fumes", "metal fumes", "antioxidant enzymes", "biomarkers", and similar terms were employed to search for articles published between 2004 and 2023. After the evaluation of article titles and abstracts, this study reviewed a total of 19 articles. Results: Studies suggest that welders experience oxidative stress due to changes in trace metals in their body fluids, affecting antioxidant enzymes and oxidative stress biomarkers. Elevated heavy metals in welders’ biological samples lead to oxidative stress and inflammation, even at low levels. Certain metals in blood and urine, such as lead (Pb), manganese (Mn), iron (Fe), chromium (Cr), and cadmium (Cd), positively correlate with serum superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels. There is also a significant positive correlation between serum/EBC MDA and blood/urine Pb, Mn, Cd, Cr, and Fe, indicating cellular damage, lipid peroxidation, and reduced antioxidant capacity. Additionally, welders may experience more DNA damage compared to non-welders. Conclusion: Exposure to WFs significantly altered oxidative stress biomarkers in bodily fluids, underscoring the importance of the relationship between oxidative stress and trace metal imbalances in WF-related injuries. These factors could serve as valuable biomarkers for monitoring workers exposed to WFs.

Background: Welding is an extensively utilized industrial technique, which involves the fusion of fumes containing various heavy metals. To protect exposed workers, it is crucial to investigate the subsequent adverse effects. This study aimed to carry out the welding process within a regulated welding chamber and examine the effects of glutathione peroxidase (GPX) and superoxide dismutase (SOD) as antioxidant enzymes and pathological damage on rat testicular tissue. Methods: Male adult Wistar rats (n=7/experiment group) were exposed to an average concentration of (44.48 mg/m3 ) welding fumes (WFs) for 30 min/d×8 days through shielded metal arc welding (SMAW). The control group (n=7) was in similar conditions without direct exposure to WFs. Results: The metal composition of WFs was found to contain iron (Fe), manganese (Mn), copper (Cu), aluminum (Al), lead (Pb), and chromium (Cr). Among these metals, Fe had the highest average concentration (12.06 mg/m3 ), while Cu displayed the lowest one (0.019 mg/m3 ). The majority of the produced particles were found within the micron size range (0.25 to 0.5 μm). The mean activity of GPX and SOD was determined 15.16777 (mU/mg protein) and 81.955 (U/mg protein) in the exposed group, respectively. In the microscopic examination of testis tissue, some complications were observed. Conclusion: Oxidative damage occurred in the testicular tissue of experimental rats by decreasing the mean activity of antioxidant enzymes. Besides, the exposed group showed reduced sperm quality and quantity indexes.

Nail technology, including the application of artificial nails and nail care, is a developing sector of the global beauty industry. Nail technicians are exposed to a variety of chemical substances through inhalation, as they spend extended periods of time in close proximity to these materials. This study aimed to evaluate the semi-quantitative health risk of dust-containing heavy metals among nail technicians. This analytical descriptive study employed the risk assessment method provided by the Singapore Occupational Health Department to evaluate the health hazards of lead, cadmium, nickel, chromium, and manganese. Dust samples from nail filing were collected from the respiratory zone of 20 nail technicians following the NIOSH 7300 method. The samples were analyzed using ICP-OES instrumentation. Monte Carlo simulation was utilized to characterize the risk and its uncertainties. Manganese and cadmium had the highest and lowest mean concentrations, respectively. The risk scores of the metals ranked from highest to lowest were as follows: [ ]. All five metals had risk rankings below 2.8, signifying a minimal risk level. Sensitivity analysis using Spearman’s correlation coefficient demonstrated a positive relationship between concentration, daily hours of exposure, and the number of workdays per week with the risk score (RR) and exposure level (ER). Conversely, the variable of weekly working hours (W) showed a negative correlation with these parameters. Despite the low-risk level of the examined metals, continuous exposure and potential long-term effects on nail technicians warrant preventive measures. Recommendations include implementing local exhaust ventilation systems, using table fans, establishing work-rest cycles, wearing N95 dust masks, and using reputable and high-quality nail polishes.

Nail salons offer a developing and diverse occupation for many women, especially the new generation. Due to the increasing apprehension surrounding heavy metals in dust caused by filing nails containing dried nail polish, the present study was designed aimed to health risk assessment of heavy metals in breathing zone of nail salon technicians (NSTs). This is a cross-sectional study that was conducted in NSTs. The concentration of Cadmium (Cd), Lead (Pb), Nickel (Ni), Chromium (Cr) and Manganese (Mn)in breathing zone of 20 NSTs was determined using ICP-OES. The metal concentrations were in the following order: Mn > Pb > Ni > Cr > Cd with corresponding arithmetic mean values of0.008, 0.0023, 0.0021, 0.001 and 0.0006 mg m^-3, respectively, which are exceeded the recommended levels stated in the indoor air guidelines. The average lifetime carcinogenic risk (LCR) for Cr, Cd, Ni and Pb was calculated 0.0084, 0.00054, 0.00026 and 1.44 E - 05, respectively. The LCR values of all metals (except Pb) exceeded the acceptable level set by the USEPA. The mean of Hazard quotients (HQ) for Mn, Cd, Cr, Ni and Pb were calculated to be23.7, 4.74, 2.19, 0.51 and 0.0.24, respectively. The sensitivity analysis showed that, the exposure frequency (EF) for Cr and Ni had the strong effects on generation of both LCR and HQ. Furthermore, the concentrations of Mn, Cd and Pb had strong impacts on the HQ generation and the concentration of Cd and Pb had main effects on LCR generation. To effectively reduce pollutant concentration, it is recommended to install a ventilation system near nail salon work tables and conduct continuous monitoring and quality control of nail products.

Welding fumes are ‘possibly carcinogenic’ according to the International Agency for Research on Cancer (IARC) and may have negative health impacts on workers who inhale them. This study examines the differences in lung tissue pathology and oxidative stress levels between rats exposed to welding fumes and a control group. Shielded metal arc welding fumes with a concentration of 50 mg/m3 were inhaled by male Wistar rats (n = 6/treatment group) for 30 min/day × 8 days. The control group (n = 6) was maintained in normal laboratory air condition. Gravimetry was used to measure the particle size distribution, which showed that most particles were in the micron range with a significant number of ≥ 0.25-sized particles. The chemical composition of the fumes was sampled for heavy metals following the National Institute for Occupational Safety and Health (NIOSH) method 7300 and analyzed by inductively coupled plasma mass spectroscopy (ICP-OES). The results showed that rats exposed to welding fumes had significant changes in SOD and GPx activity compared to the control group. The mean activity of GPx in the control and experiment groups was 16.34380 (mU/mg protein) and 11.81042 (mU/mg protein), respectively. The mean activity of SOD in the control and experiment groups was 275.587 (U/mg protein) and 121.168 (U/mg protein). The lung tissues of the control rats were normal, while the exposed rats showed mild to severe tissue injuries in the bronchial and alveolar spaces and the alveolar septa.

Background: Fatigue, depression, and job satisfaction are very important variables in job scopes that, if not managed properly, significantly impact job performance. This study aimed to investigate the association between occupational fatigue and burnout levels with job satisfaction among taxi drivers in Isfahan. Materials and Methods: This descriptive study in ...

Computational fluid dynamics (CFD) is an indispensable simulation tool for predicting the emission of pollutants in the work environment. Welding is one of the most common industrial processes that might expose the operators and surrounding workers to certain hazardous gaseous metal fumes. In the present study, we used computational fluid dynamics (CFD) methodology for simulating the emission of iron fumes from the shielded metal arc welding (SMAW) procedure. A galvanized steel chamber was fabricated to measure the pollutant concentration and identify the size of the fume created by the SMAW. Then, the emission of welding aerosol was simulated using a method of computational fluid-particle dynamics with the ANSYS 2020 R1 software. The highest amount of welding fumes concentration was related to iron fumes (i.e., 3045 μg/m³ with a diameter of 0.25 μm). The results of the current study indicated that the local exhaust and general ventilation system can prevent the spreading of welding fumes to the welder’s breathing zone and the surrounding environment. CFD was also found to be an efficient method for predicting the emission of the iron fumes created by SMAW as well as for selecting an appropriate ventilation system. However, further studies that take the modeling of welding-generated emission of additional metal particles and gases into account will need to be undertaken.

One of the most important occupational and environmental pollutants are biological agents such as various types of viruses. Recently the 2019-nCoV causes lower respiratory tract disease, called novel coronavirus pneumonia that in addition to causes physical disorders, can lead to mental health problems. This study looks at some of the articles that deal with psychological problems caused by the coronavirus pandemic in different groups of people. For this purpose, a review of the published literature was performed in some databases (PubMed, Google Scholar, Elsevier) and related references were used.