Archives of Hygiene Sciences
Volume:10 Issue: 1, Winter 2021

Background & Aims:

 of the Study: One of the most important environmental pollutants in the alcohol industry is sugar beet molasses. The wastewater of these industries causes the pollution of soil, surface water, and underground water. Iron oxide magnetic nanoparticles have attracted much consideration due to their unique properties, such as superparamagnetism, surface-to-volume ratio, greater surface area, and easy separation methodology. Accordingly, clinoptilolite zeolite has been used due to the low cost and abundance. The purpose of this study was to remove organic and dye pollutants from the wastewater using a new catalyst that can be separated from aqueous solution by magnetic methods and take a step toward the preservation of the environment.

In this study, a new catalyst was prepared by supporting magnetite (Fe3O4) on clinoptilolite zeolite, and the characterization of this catalyst was  studied by using scanning electron microscopy images, X-ray diffraction patterns, and nitrogen adsorption/desorption.

The experiments were performed in different operational conditions, such as the amounts of photocatalyst and pH. The mathematical equation for estimating the percentage of dye pollutant removal was obtained using the Box-Behnken experimental design. The optimal conditions were determined as the amount of photocatalyst equal to 200 mg L-1, pH equal to 2, and concentration of H2O2 equal to 25 ppm. Removal efficiency in the optimal condition was reported as 85.10%.

The obtained results of the present study showed that the photocatalytic process can be suitable for the removal of dye pollutants from the alcohol industrial wastewater using the supported Fe3O4 nanoparticles on zeolite clinoptilolite.

Background & Aims :

of the Study: Management and leadership style is one of the characteristics that can be of great help to organizations in the competitive world of industries and organizations. On the other hand, individual factors can also play a decisive role in organizational issues. In competition with other organizations, the retention of human resources which is a daunting challenge for numerous organizations is also regarded as a competitive organizational advantage (8). The present study aimed to determine the role of organizational and individual factors on employeeschr('39') intention to stay with an organization in one of the cement factories in southern Iran in 2018.

The present cross-sectional descriptive-analytical study 142 participants who were randomly selected from among all operational workers on fixed day shifts and rotational shiftwork. Data collection tools included the following questionnaires: a researcher-made demographic form, body map, the intention to stay questionnaire, safety leadership questionnaire developed by Tabibi, and paternalistic management scale designed by Cherry. The obtained data were analyzed in LISREL and SPSS software (version 20) using descriptive and analytical methods, as well as structural equation modeling.

The used instruments were reported to be reliable rendering a Cronbachchr('39')s alpha coefficient of > 0.7. The results of the body map questionnaire demonstrated that 31 (23.9%) employees reported pain in the lower back as painful and very painful, which was higher than pain scores in other parts of the body. Moreover, paternalistic management, safety leadership, and stress did not show a significant effect on the variables of authoritarianism, musculoskeletal disorders, and the intention to stay, respectively (P> 0.05).

As evidenced by the obtained results, when people in authority assume a paternal role in organizations and receive the expected responses from their subordinates, they will witness a remarkable decrease in employeeschr('39') intention to leave their present organization.

Background & Aims:

 of the Study: 4-Nitrotoluene (4NT) is a toxic, resistant, and carcinogenic pollutant. The current study aimed to investigate the degradation and mineralization of 4NT regarded as one of the components of petrochemical wastewater using MnO2/Clinoptilolite (CP)/O3 process. The present study also examined the effect of several operational parameters.

 Synthesized wastewater was used in this study. It is proposed to apply a radical mechanism by the generation of an anion radical (   prior to hydroxyl radical in order to describe the interaction between ozone and MnO.

The obtained findings of the present study are not similar to those of the ozonation process alone. In ozonation, 4NT removal was positively affected by higher pH due to the formation of hydroxyl radicals. The degradation efficiency values of 4NT in optimum pH for the ozonation and MnO2/CP/O3 processes were reported as 89.0 and 98.5% within 75 min of reaction, respectively.

In addition, it was obviously shown that the degradation efficiency of 4NT was higher at neutral pH conditions (pH=7) in catalytic ozonation. The removal of the chemical oxygen demand (COD) increased from 50% (only ozonation) to 69.5% (MnO2/CP/O3) after 75 min of reaction. The kinetic of degradation was pseudo first-order. Furthermore, the degradation and relative mineralization of 4NT were estimated by high-performance liquid chromatography and COD, respectively.

Background & Aims :

of the Study: The dyes present in the effluent from the textile industry are among the most polluted and hazardous wastewater discharged, causing severe changes in water quality and the environment. The use of agricultural residues as inexpensive organic adsorbents is very suitable for removing industrial dyes from aquatic solutions, especially in developing countries. This study aimed to investigate the effectiveness of activated carbon synthesized from carrot waste as an inexpensive and available organic adsorbent in the removal of Acid Red 18 (AR18) dye.

In this study, response surface methodology (RSM) was discussed as an efficient method for the optimization of AR18 adsorption onto PAC‎ (obtained from waste carrot) coated with Fe3O4 nanoparticles. ANOVA analysis based on the Box-Behnken design-RSM was applied to investigate the correlation coefficient of PAC (Synthesized Carrot Waste). Adsorbent dose, initial dye concentration, and pH were optimized and evaluated using RSM with respect to contact time on adsorption of AR18. Moreover, X-ray diffraction, transmission electron microscopy, Brunauer–Emmett–Teller, Fourier-transform infrared, and field emission scanning electron microscopy techniques were used to study the adsorbent properties and characteristics of PAC‎. Isotherm data were modeled with both Langmuir and Freundlich isotherm.

The results obtained from Langmuir isotherm showed the best fit to experimental data proposing homogeneous dispersion of adsorption sites. Moreover, the compatibility of the adsorbent was examined by fitting the adsorption data with a pseudo-second-order kinetic model. The results of ANOVA analysis showed a good fit between quadratic model predictions with experimental values, resulting in R2 of 0.997 for PAC. The results showed 99.7% of dye AR18 was removed after 80 min, pH at 3, and the adsorbent dose of 1.5 g.

It can be concluded that PAC‎ (Synthesized Carrot Waste) has great potential applications for the removal of AR18 dye from the textile industry. Large-scale applications of adsorbent and adsorbate, due to their recuperation and reusability characteristics, are proposed by observations and experimental results of this study.

Background & Aims :

of the Study: Recently, there has been a surge of interest in spirituality and spiritual well-being due to their numerous beneficial organizational outcomes. Organizational commitment and turnover have been considered as positive and negative factors, respectively, in the success and productivity of organizations. Given the relationship among spiritual well-being, organizational commitment, and turnover, this study investigated spiritual well-being at the workplace and its relationship with organizational commitment and turnover among the employees of the selected textile companies in Qom province, Iran in 2016.

This descriptive-analytical study was performed on 222 employees of selected textile companies in Qom province. The participants were selected using the stratified sampling method. The required data were collected using three questionnaires, namely a demographic characteristics form, Spiritual Well-Being Scale by Ellison and Paloutzian, and Allen-Meyer Organizational Commitment Questionnaire. It should be mentioned that the validity and reliability of the Persian version of these questionnaires were confirmed. The collected data were analyzed using descriptive statistics, Pearson correlation coefficients, one-way analysis of variance, and Chi-square in SPSS software (version 20).

Based on the findings, the mean values of total spiritual well-being and organizational commitment of employees were 98.26±14.92 and 105.23±18.6, respectively. There were positive correlation coefficients and significant correlations between total spiritual well-being and organizational commitment (P˂0.01). In addition, the results showed that turnover had negative significant correlations with all aspects of spiritual well-being and organizational commitment (P˂0.01).

Based on the results, it is possible to optimize workplace conditions and productivity by improving the spiritual well-being of the employees.

Background & Aims:

 of the Study: Recently, the advanced oxidation processes have received growing attention in industrial wastewater treatment. In this project, the degradation and mineralization of an aqueous environment containing nitrobenzene (NB) as the main carcinogenic contaminant were inspected by a Fenton-like process. In addition, the influence of operational variables, such as initial concentrations of H2O2, Ferric ion, and pH on the removal of NB was investigated.

The Box-Behnken design (BBD) of experiments and the response surface methodology were applied to explore the effects of three independent variables on the response functions to get the optimum conditions. Analysis of variance (ANOVA) was used to determine the significance of the effects of independent variables on the response function. Different amounts of variables were optimized for the removal of NB in the Fenton-like processes.

At optimum conditions (H2O2 and Ferric concentrations of 15.33 and 1.30 mM, respectively, and a pH of 6.23) and after 30 min of reaction, the removal efficiency for NB and chemical oxygen demand (COD) were 99.0% and 56.7%, respectively.

The Fenton-like process influenced the removal of NB; however, it could only remove the COD to some extent. The obtained results at optimized circumstances were outstanding from the environmental point of view.

Background & Aims:

 of the Study: The prevalence of food insecurity in many countries and the challenges emerging to feed more than 9 billion people by 2050 have led the researchers to look for alternative sources of protein in human and animal diets. In this regard, today, the use of insects has attracted a lot of attention since they contain high nutritional value and help to preserve environmental resources. Among the various species of insects, particular attention has been paid to the black soldier fly (BSF) since it can consume from a variety of substrates, including organic waste. Various factors, such as temperature, humidity, density, light, and diet, are involved in the breeding of this insect. It seems that temperature is more effective in the breeding stages of this species than the other factors. Due to the insufficient information on finding the optimal temperature in breeding this species, this study was conducted to determine the mentioned factor in the maximum production and reproduction of black soldier flies to eliminate organic waste and turn it into valuable material in animal food.

Organic waste, including kitchen fruit and food, was used to feed the larvae. Adult flies were then reared in cotton net cages (40´40´40 cm) and under the temperature range of 25-35°C. Afterward, the eggs were collected by fine needles and transferred to a temperature-controlled incubator during the hatching stage to undergo experiments in the specified temperature range (i.e., 25-35°C). The larvae fed freely from the formulated diet (i.e., chicken feed) until the pre-pupal stage. The produced pupae were monitored for growth and survival in the temperature range of 25-35°C. The emergence of adult BSFs at different temperatures was examined after the completion of the pupal stage under controlled temperature. In this descriptive study after the completion of each insectchr('39')s development stage, the percentage of insect survival in each stage of measured temperature condition was determined by estimating the proportion of the attribute present in the population.

According to the results of this study, the highest hatching percentage (80%) was recorded at 30°C for 4 days, while the slowest growth period was obtained at 30°C for 13 days with a survival rate of 92%. It was also revealed that the highest pre-pupal and pupal survival rates were 82% at 30°C for 10 days and 77% at 30°C  for 7 days, respectively. The lifespan of adult flies at 30°C was reported to be 9 days. The statistical population of this consisted of 300 pupae at each temperature. The survival percentage was reported after the survived pupae were counted.

The results of this study showed that the growth and reproduction of BSFs were significantly affected by temperature. In this study, the optimum temperature in the breeding of BSFs was obtained as 30°C. Temperature can also affect the insectchr('39')s biological life cycle, such as immaturity survival and adult lifespan, growth, fertility, gender ratio, and population growth parameters.

Background & Aims:

 of the Study: Although industrial development has raised living standards, it has increased the rate of incidents. To cope with the adverse effects of these incidents, multiple infrastructures are needed, such as the training of professionals. The present study aimed to formulate training topics needed by chemical accident teams.

This qualitative applied research was conducted based on the content analysis method in 2020. In this research, the needed competencies were determined based on the human resource competency model and using the opinion of experts and standards. Thereafter, the training topics of were designed with an emphasis on the health of the operational teams. The needed data were collected through library studies and semi-structured interviews. The validity of the training courses was also assessed using the Content validity index.

The required training topics which were identified in three groups were as follows: Oreintation with hazardous chemicals, effects of hazardous chemicals on the body, detoxification, safety principles in hazardous chemical accidents, advanced personal equipment, behavior of hazardous chemicals, determining the health status of operational teams, Oreintation with the needs of the body during operations, as well as the assessment of scene and casualties of hazardous chemical accidents.

It is expected that team members will acquire the necessary skills to protect themselves and others after attending the training courses. Moreover, based on the findings, some constructive suggestions were put forward to boost the chemical defense system which can be of great help for future researchers and management policymakers.

Background & Aims :

of the Study: Antibiotics are pharmaceutical compounds which are stable in the environment and their discharge without treatment can cause pollution of the environment. The current study aimed to assess the efficicacy of cupric oxide nanoparticles (CuO-NPs) as another kind of adsorbent for the removal of penicillin G (PG) from its aqueous media, as well as kinetic analysis of PG removal.

In the present study, batch experiments were conducted on a laboratory scale. During the process of adsorption, the optimum conditions (including contact time, initial PG concentration, initial pH, and dosage of CuO-NPs) were determined. The sorption data was fitted into the pseudo-first-order (PFO), pseudo-second-order (PSO), Bhattacharya-Venkobachar, and intraparticle diffusion models.

As evidenced by the obtained results, the maximum removal efficiency for PG (83%) was measured at pH 6, CuO-NPs dose of 1 g/L,  PG concentration of 25 mg/L and the contact time of 60 min with adsorption capacity (qe) of 15 mg/g. The sorption data were more adequately fitted into the PSO model.

Based on the findings of the present study, CuO-NPs are efficient for PG removal; therefore, they can be employed for PG reduction from the environment.