Relationship between Occupational Exposure to Respirable Crystalline Silica and Serum Copper Level as an Indicator of Silicosis: A Systematic Review and Meta-analysis.

Background: This systematic review and meta-analysis study evaluates a relationship between occupational exposure to respirable crystalline silica and serum copper (Cu) levels as an indicator for early detection of silicosis. Materials and Methods: A systematic search was conducted, and the quality of results was evaluated in accordance with the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The following databases were searched, including Web of Sciences, Scopus, and PubMed from inception until November 2021. The following keywords were selected for searching in the mentioned databases including, "copper" OR "serum copper" AND "silicosis". The mean (standard deviation [SD]) of Cu was extracted for both silicosis and non-silicosis subjects. The differences in mean effect size were pooled using the random-effect model. Heterogeneity and publication bias were evaluated using the I2 value and Begg's test and Egger's test, respectively. Results: A total of 159 studies were initially found, among which eight studies were included in the meta-analysis. Random-effect meta-analysis of these eight studies showed that silicosis patients had higher copper levels than the non-silicosis group with a pooled standardized mean difference (SMD) of 3.02 (95% confidence interval: 0.25, 5.78); I2 = 99.3%, P value < 0.001. The subgroup analysis showed that the corresponding figures in those with mean age >40 years and <40 years were 5.79 (2.06, 9.52) and -0.43 (-4.57, 3.70), respectively. Moreover, no publication bias was found in the analyses. Conclusions: The results of the present study demonstrated that silica exposure may be associated with increasing serum Cu levels.

Arsenic in drinking water and kidney cancer: a systematic review.

OBJECT: Arsenic as a chemical is found in rock, soil, air and used in various industries and their products, such as colors, hairs, and fertilizers. Humans may be exposed to arsenic mainly through food and drinking water. Due to its adverse health effects, its presence in drinking water has become a public health concern. METHODS: In this systematic review, we investigated the relationship between arsenic concentration in drinking water and the risk of kidney cancer in humans. For this reason, various electronic databases were searched from 1992 February to November 2021. In this review, three ecological studies, two case-control studies, and four cohort studies were investigated. RESULTS: High levels of arsenic (100 µg/L) have been reported in many countries such as southwest Taiwan, Niigata, Argentine, and northern Chile. A significant relationship was observed between kidney cancer incidence and its mortality rate with high arsenic levels in drinking water. CONCLUSIONS: Despite the limitations in some previous studies, reviewing and comparing the data of different regions indicates a scientific relationship between kidney cancer incidence and high concentrations of arsenic in drinking water.

Evaluation of SARS-CoV-2 in Indoor Air of Sina and Shahid Beheshti Hospitals and Patients' Houses.

Side by side air sampling was conducted using a PTFE filter membrane as dry sampler and an impinger containing a suitable culture medium as a wet sampler. Most of the samples were collected from two hospitals and few air samples were collected from private houses of non-hospitalized confirmed COVID-19 patients. The collected air samples were analyzed using RT-PCR. The results indicated that all air samples collected from the hospitals were PCR negative for SARS-CoV-2. While two of four air samples collected from the house of non-hospitalized patients were PCR positive. In this study, most of the hospitalized patients had oxygen mask and face mask, and hence this may be a reason for our negative results regarding the presence of SARS-CoV-2 in indoor air of the hospitals, while non-hospitalized patients did not wear oxygen and protective face masks in their houses. Moreover, a very high concentration of particles in the size range of droplet nuclei (< 5 µm) was identified compared to particles in the size range of respiratory droplets (> 5-10 µm) in the areas where patients were hospitalized. It can be concluded that using face mask by patients can prevent the release of viruses into the indoor air, even in hospitals with a high density of patients.

Concentration of Potentially Toxic Elements in Vegetable Oils and Health Risk Assessment: a Systematic Review and Meta-analysis.

The present study evaluates the concentration of potentially toxic elements (PTEs), including Pb, Cd, As, Fe, Zn, Cu, and Ni, in vegetable oils through a meta-analytic approach. The published studies in relation to the concentrations of PTEs in vegetable oils were retrieved from major international databases such as PubMed, Scopus, Web of Science, and Embase followed by meta-analysis. Moreover, the health risk assessment was evaluated using total target hazard quotient (TTHQ) by a Monte Carlo simulation (MCS) model. According to the results of 51 articles included among 958 retrieved studies, the concentrations of the PTEs were as follows: Cd ≈As (0.110 mg/kg) > Pb (0.086 mg/kg) in cottonseed, canola, and olive oil and Fe (12.964 mg/kg) > Zn (1.044 mg/kg) > Ni (0.893 mg/kg) > Cu (0.264 mg/kg) in cottonseed, olive, and soybean for trace elementals, respectively. Based on the continent type, the higher concentration of Cd, As, and Pb was related to PAHO (American region) and AFRO (African region), and the higher concentrations of Fe, Zn, Cu, and Ni were observed in WPRO (Western Pacific Region), EMRO (Eastern Mediterranean Region), and AFRO. On the other hand, non-carcinogenic health risk assessment of the PTEs indicated that there was a different risk pattern in various countries, and the TTHQ level in adult groups was lower than 1. It can be concluded that the consumption of vegetable oils is safe and does not pose risk to the health of consumers.

Management of Dental School During the COVID-19 Pandemic: Application of Intervention Mapping.

Background: Coronavirus Diesease-2019 (COVID-19) outbreak has led to the suspension of the activities of dental schools. Therefore, reorganizing clinical settings and supporting services as quickly as possible has received much attention to reopen dental schools. The present study aimed to evaluate the applicability of the Intervention Mapping (IM) approach for designing, implementing, and evaluating an intervention program to prevent and control COVID-19 in dental schools. Methods: Following the IM protocol, six steps were completed in the planning and development of an intervention, targeting, and management of Dental School during the COVID-19 pandemic. Results: The information obtained from the needs assessment revealed that the COVID-19 outbreak prevention was associated with the use of personal protective equipment by all target groups, infection control measures taken in the environment, preparation of the environment and equipment, changes in the treatment plan according to the COVID-19 pandemic, changing the admission process of patients, and reduction of attendance of target groups in the school are linked with. In this study, determinant factors affecting the COVID-19 prevention at the individual level were identified based on the Protection Motivation Theory (PMT). In this program, various methods, such as presentation of information, modeling role, and persuasion measures, were utilized and the practical programs included educational films and group discussions implemented. Conclusions: Our findings indicated that intervention in dental environments on the basis of the IM process can develop a comprehensive and structured program in the dental school and hence can reduce the risk of the COVID-19 infection.

Antimicrobial properties of Peganum harmala L. seeds' smoke in indoors: applications and prospects.

Peganum harmala L., known as Harmal or African, Syrian Rue, Espand (in Iranian culture), and Ozallaik (in Turkey), is a perennial herbaceous glabrous plant, which offers many antimicrobial activities in indoor air. In this regard, in the present study, we aimed at evaluating the disinfectant effects of Peganum harmala L. (PHL) seed smoke on microbial load in air. For this reason, the effects of four doses of PHL seeds (5, 10, 15, and 20 g) and various sampling times in the range of 0-30 min were examined on its antibacterial and antifungal effects. The experiments were conducted at two different areas including a classroom located at the health faculty of Ahvaz University of Medical Sciences and a residential area with a similar volume of 60 m3. Tryptic soy agar (TSA) was applied as a specific bacterial culture medium, and sabouraud dextrose agar (SDA) was used as a specific fungal culture medium. The concentration of bacteria and fungi in the indoor air of the residential area decreased by 71.4 and 94.7%, respectively. In the educational area, the concentration of bacteria and fungi decreased by 92.8 and 88.9%, respectively. In conclusion, the PHL smoke showed antibacterial and antifungal effects, which may be due to its alkaloids harmine properties, while it causes an increase in the concentration of particles in the air of indoor environments. Therefore, it can be used as an indoor air disinfectant for decreasing the load of bacteria and viruses in a closed space.

Are photocatalytic processes effective for removal of airborne viruses from indoor air? A narrative review.

A wide variety of methods have been applied in indoor air to reduce the microbial load and reduce the transmission rate of acute respiratory diseases to personnel in healthcare sittings. In recent months, with the occurrence of COVID-19 pandemic, the role of portable ventilation systems in reducing the load of virus in indoor air has received much attention. The present study delineates a comprehensive up-to-date overview of the available photocatalysis technologies that have been applied for inactivating and removing airborne viruses. The detection methods for identifying viral particles in air and the main mechanisms involving in virus inactivation during photocatalysis are described and discussed. The photocatalytic processes could effectively decrease the load of viruses in indoor air. However, a constant viral model may not be generalizable to other airborne viruses. In photocatalytic processes, temperature and humidity play a distinct role in the inactivation of viruses through changing photocatalytic rate. The main mechanisms for inactivation of airborne viruses in the photocatalytic processes included chemical oxidation by the reactive oxygen species (ROS), the toxicity of metal ions released from metal-containing photocatalysts, and morphological damage of viruses.

Electrodisinfection of bacteria-laden in surface water using modified Ti electrode by antimony-and nickel-doped tin oxide composite.

Providing clean and safe drinking water by point of use (POU) disinfection methods has become a critical issue, especially in crises and epidemics. In this study, antimony-and nickel-doped tin oxide electrode (Ni-Sb-SnO2) was employed as an electrode for electro-catalytic disinfection of surface water. The synthetized electrodes were characterized using scanning electron microscope, linear sweep voltammetry and X-Ray diffraction techniques. The results revealed that the highest electrochemical disinfection efficiency was achieved by the Ni-Sb-SnO2 electrode under weak acidic conditions and its performance decreased with increasing pH towards alkaline environment. Based on the results, total coliform (TC) and fecal coliform (FC) were completely removed at current density of 0.67 mA cm-2. Moreover, the electrochemical disinfection of microorganisms showed that the process efficiency was directly proportional to increasing time and at 0.6 C cm-2 of charge passed, 3-log removal of the both indicators occurred after 15 min. The highest removal efficiency of TC and FC was also achieved at 8 mmol of NaCl concentration at <10 min of detention time. The results of this study depicted that the Ti/Ni-Sb-SnO2 electrode provides higher disinfection efficiency for the removal of TC and FC compared with Ti and SS/PbO2 electrodes. Moreover, the proposed system was able to completely eliminate heterotrophic, Streptococcus faecalis and Pseudomonas aerogenes indicators under optimal conditions. Therefore, it can be concluded that the proposed electrochemical system can be efficiency applied as a POU disinfection system for disinfection of water contaminated with microbial indicators, especially for crises and epidemics.

Sampling and detection of corona viruses in air: A mini review.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a strain of coronaviruses that causes coronavirus disease 2019 (COVID-19). In these days, the spread of the SARS-CoV-2 virus through the air has become a controversial topic among scientists. Various organizations provide standard methods for monitoring biological agents in the air. Nevertheless, there has been no standard recommended method for sampling and determination of viruses in air. This manuscript aimed at reviewing published papers for sampling and detection of corona viruses, especially SARS-Cov-2 as a global health concern. It was found that SARS-Cov 2 was present in some air samples that were collected from patient's rooms in hospitals. This result warrants its airborne transmission potential. However, due to the fact that in the most reviewed studies, sampling was performed in the patient's room, it seems difficult to discriminate whether it is airborne or is transmitted through respiratory droplets. Moreover, some other disrupting factors such as patient distance from the sampler, using protective or oxygen masks by patients, patient activities, coughing and sneezing during sampling time, air movement, air conditioning, sampler type, sampling conditions, storage and transferring conditions, can affect the results. About the sampling methods, most of the used samplers such as PTFE filters, gelatin filers and cyclones showed suitable performance for trapping SARS-Co and MERS-Cov viruses followed by PCR analysis.

Preparation of Carbotrap/silica composite for needle trap field sampling of halogenated volatile organic compounds followed by gas chromatography/mass spectrometry determination.

BACKGROUND: A needle trap device (NTD) was packed with Carbotrap/silica composite sorbent and applied for field sampling of halogenated volatile organic compounds (HVOCs) followed by gas chromatography/mass spectrometry (GC/MS) separation and determination. METHODS: Carbotrap B, as a highly pure surface sorbent, was prepared using sol-gel method to improve its surface properties for adsorption/desorption of the target analytes. The effects of important experimental variables on the sampling and determination of trichloroethylene (thrCE) and tetrachloroethylene (tetCE) using the proposed NTD-GC/MS strategy were evaluated and optimized. RESULTS: The results showed that sampling temperature and relative humidity interfered with sampling efficiency of the developed method and peak area responses of the analytes decreased with increasing temperature and relative humidity. The peak areas of the analytes increased with raising desorption temperature from 180 to 250 °C, and increasing desorption time from 1 to 3 min. The carryover experiments showed that the carryover effect disappeared after 3 min of desorption time. The Limits of Detection (LODs) and Limits of Quantitation (LOQs) of the analytes were in the range 0.01-0.03 and 0.05-0.09, respectively. CONCLUSIONS: The results indicated that the developed NTD-GC/MS procedure can be used as a technology with high sensitivity for the field sampling and determination of HVOCs.

Development of Carbotrap B-packed needle trap device for determination of volatile organic compounds in air.

Carbotrap B as a highly pure surface sorbent with excellent adsorption/desorption properties was packed into a stainless steel needle to develop a new needle trap device (NTD). The performance of the prepared NTD was investigated for sampling, pre-concentration and injection of benzene, toluene, ethyl benzene, o-xylene, and p-xylene (BTEX) into the column of gas chromatography-mass spectrometry (GC-MS) device. Response surface methodology (RSM) with central composite design (CCD) was also employed in two separate consecutive steps to optimize the sampling and device parameters. First, the sampling parameters such as sampling temperature and relative humidity were optimized. Afterwards, the RSM was used for optimizing the desorption parameters including desorption temperature and time. The results indicated that the peak area responses of the analytes of interest decreased with increasing sampling temperature and relative humidity. The optimum values of desorption temperature were in the range 265-273°C, and desorption time were in the range 3.4-3.8min. The limits of detection (LODs) and limits of quantitation (LOQs) of the studied analytes were found over the range of 0.03-0.04ng/mL, and 0.1-0.13ng/mL, respectively. These results demonstrated that the NTD packed with Carbotrap B offers a high sensitive procedure for sampling and analysis of BTEX in concentration range of 0.03-25ng/mL in air.

Preparation and catalytic activity of bone-char ash decorated with MgO - FeNO3 for ozonation of reactive black 5 dye from aqueous solution: Taguchi optimization data.

Reactive dye is one of the most applicable dyes in textile industries which its release to the water bodies creates a concern for environmentalists. Here, in this data article a bone-char (BC) ash decorated with MgO-FeNO3 for removing reactive black 5 (RB5) dye in a catalytic ozonation process (COP) system. Operational parameters data such as initial RB5 concentration, pH, catalyst dosage, and reaction time were optimized using Taguchi method. The optimal conditions for initial RB5 concentration, pH, catalyst dosage, and reaction time were determined 10 mg/L, 10, 0.1 g/L, and 15 min, respectively. Data of Taguchi optimization tests indicated that the initial RB5 concentration had a significant influence on RB5 removal efficiency (54.03%) during the catalytic ozonation process, and reaction time had lower contribution (2.04%).

Comparing the performance of granular coral limestone and Leca in adsorbing Acid Cyanine 5R from aqueous solution.

The effect of granular coral limestone and Leca as adsorbents for removing Acid Cyanine 5R (AC5R) from aqueous solution was studied. The optimum pH and adsorbent particles size in both adsorbents were determined to be 3 and 297 µm, respectively. The optimum dosages of coral limestone and granular Leca were 0.150 and 0.145 g/mg of dye, respectively. Also, results have shown that the adsorption efficiency by both coral limestone and Leca increased with the decreasing adsorbent particles size. Moreover, under similar conditions, the maximum removal efficiency by granular coral limestone and Leca was 94% and 88%, respectively. The results revealed that the performance of granular coral limestone was better in AC5R removal than that of Leca granulated under such condition. In total, granular coral limestone and Leca act as suitable adsorbents for removing dye pollutants from an aqueous solution.

Determination of Pesticides Residues in Cucumbers Grown in Greenhouse and the Effect of Some Procedures on Their Residues.

BACKGROUND: The objective of this study was to determine the residual concentrations of ethion and imidacloprid in cucumbers grown in greenhouse. The effect of some simple processing procedures on both ethion and imidacloprid residues were also studied. METHODS: Ten active greenhouses that produce cucumber were randomly selected. Ethion and imidacloprid as the most widely used pesticides were measured in cucumber samples of studied greenhouses. Moreover, the effect of storing, washing, and peeling as simple processing procedures on both ethion and imidacloprid residues were investigated. RESULTS: One hour after pesticide application; the maximum residue levels (MRLs) of ethion and imidacloprid were higher than that of Codex standard level. One day after pesticide application, the levels of pesticides were decreased about 35 and 31% for ethion and imidacloprid, respectively, which still were higher than the MRL. Washing procedure led to about 51 and 42.5% loss in ethion and imidacloprid residues, respectively. Peeling procedure also led to highest loss of 93.4 and 63.7% in ethion and imidacloprid residues, respectively. The recovery for both target analytes was in the range between 88 and 102%. CONCLUSION: The residue values in collected samples one hour after pesticides application were higher than standard value. The storing, washing, and peeling procedures lead to the decrease of pesticide residues in greenhouse cucumbers. Among them, the peeling procedure has the greatest impact on residual reduction. Therefore, these procedures can be used as simple and effective processing techniques for reducing and removing pesticides from greenhouse products before their consumption.

An epidemiological study of cutaneous leishmaniasis using active case finding among elementary school students in Pakdasht, southeast of Tehran, Iran 2013-2014.

BACKGROUND: Cutaneous leishmaniasis is one of the prevalent health problems in tropical and subtropical areas including Iran. Therefore, it is essential to identify the prevalence and new foci of this disease in different regions of Iran. This study aimed to determine the epidemiology of cutaneous leishmaniasis by active surveillance in elementary schools in Pakdasht City, Southeast of Tehran, Iran 2013-2014. METHODS: This cross sectional study was carried out on 4800 students from 60 elementary schools in Pakdasht during October 2013 to March 2014. After examining the students, some epidemiological data such as age, gender, date, anatomic location of the lesion(s) in the body, number and size of lesion(s), lesion type, and travel history to endemic areas was recorded in a checklist. Students with active lesions were examined using parasitological and molecular methods (PCR). RESULTS: Totally, 31 students (0.64%) had leishmaniasis, of which 15 (0.31%, 95% CI, 0.15%, 0.47%) had active lesions and 16 (0.33%, 95% CI, 0.17%, 0.49%) had leishmaniasis scars. Molecular testing showed that Leishmania major was the causative agent of leishmaniasis in all patients with active lesion. The highest frequency of cutaneous leishmaniasis was found in the age group 10-12 years (P=0.03). There was a significant difference between the frequency of the disease in different months (P=0.04) and the anatomic location of the lesion/scar (P=0.04). Moreover, t-test revealed that there was a significant relationship between number of lesions/scars and the age group (P<0.001). CONCLUSIONS: The leishmanial type diagnosed in all patients was L. major. This finding suggests that Pakdasht might be a new focus for zoonotic cutaneous leishmaniasis.

Performance catalytic ozonation over the carbosieve in the removal of toluene from waste air stream.

BACKGROUND: Toluene is a volatile organic compound, one of 189 hazardous air pollutants (HAPs) and the most important pollutant found in most industries and indoor environments; owing to its adverse health, toluene must be treated before being released into the environment. METHODS: In this research study, a continuous-flow system (including an air compressor, silica gel filters and activated charcoal, impinger, an ozone generation and a fixed bed reactor packed with the carbosieve in size 1.8-2.3 mm, specific surface: 972 m2/g,) was used. This glass reactor was 0.7 m in height; at a distance of 0.2 m from its bottom, a mesh plane was installed so as to hold the adsorbent. Moreover, 3 l/min oxygen passed through this system, 0.43 g/h ozone was prepared. The flow rate of waste airstream was 300 ml/min. The efficiency of this system for removal of toluene was compared under the same experimental conditions. RESULTS: Under similar conditions, performance of catalytic ozonation was better in toluene removal than that of ozonation and carbosieve alone. On average, increasing the removal efficiency was 45% at all concentrations. When carbosieve and ozone come together, their synergistic effects increased on toluene degradation. CONCLUSIONS: Catalytic ozonation is a suitable, high-efficient and available method for removing toluene from various concentrations of waste air stream. This process due to the short contact time, low energy consuming and making use of cheap catalysts can be used as a novel process for removing various concentrations of volatile organic compounds.