Journal of Preventive Medicine

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Introduction: Microbial contamination of bread can endanger the health of consumers. The aim of this study was to determine the microbial contamination of bread and hands of workers directly supplying bread in selected bakeries in Bandar Abbas.
Methods: In this descriptive-analytical study conducted in 2020, 76 bakeries were randomly selected and bread samples were taken using relative stratified sampling method, based on the baking type, and transferred to the food laboratory to measure the microbial load. Also, from each bakery, a bread distributor was selected to investigate the hand microbial contamination. The microbial load of bread samples was measured in a food lLaboratory and the microbial load of workers' hands was measured using an SSP device. Statistical analysis was performed using SPSS software. Mean and standard deviation parameters were used to describe the data and Chi-square test was used to examine the relationship between variables at a significance level of 0.05.
Results: Based on the results, out of a total of 76 samples taken from the workers, 51 samples (80%) were found to be infected with microorganisms. Having a health card, using face masks, and respecting personal hygiene, social distancing, and disinfection protocols had a significant relationship with workers' hand contamination (P-Value<0.05). The results of measuring the microbial load of bread samples showed that all samples were free of microbial contamination.
Conclusion: Despite no microbial contamination in the bread samples, contamination of workers' hands can be a source of microbial contamination for bread. Therefore, it is recommended that health officials consider strict controls over personal hygiene and the health of bakeries.

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Introduction: Vegetables are one of the most critical groups in people's diet, and quality assurance plays a significant role in health and food safety. Consumption of vegetables is one of the main exposure routes for heavy metals. This study aimed to assess the carcinogenic and non-carcinogenic risks of vegetables cultivated around the Tehran landfill areas in 2019.
Methods: This descriptive study was conducted using available sampling method in 2019 on eight types of vegetables. The concentrations of heavy metals were measured using ICP-OES after acidic digestion. The carcinogenic and non-carcinogenic risks were calculated using the related equations. SPSS software was used to determine the relationships between the variables.
Results: The results showed that the order of heavy metals concentration was Al> Fe> Zn> Mn> Cu> Ni> Pb> As> Cr> Co> Cd. The order of contamination load in different vegetables was lettuce> leek> dill> tomato> eggplant> potato> onion> cabbage. Pearson coefficient correlation showed a very strong significant relationship between Cd with Pb, Mn, and Ni at the level of 1%. Hazard quotient (HQ) and hazard index (HI) values in all vegetables were below 1, indicating no potential risk for children and adults. Lettuce, leeks, dill, tomatoes, and eggplant and lettuce, dill, and leeks had significant carcinogenic risk for children and adults, respectively.
Conclusion: Considering that long-term consumption of vegetables can expose the consumers to significant carcinogenic risk, mitigation measures and continuous monitoring of heavy metals in crops cultivated in the landfill areas are essential.
 

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Introduction: Azo dyes are considered a potential risk to the environment due to their widespread use in various industries as well as their toxicity. Therefore, effective removal of this pollutant from the environment seems to be necessary. The aim of this study was to investigate the process of heterogeneous Fenton with zero-valent iron particles in the removal of an azo dye.
Methods: The present experimental study was performed in 2019 in a laboratory scale in a batch reactor. In this study, the efficiency of heterogeneous Fenton-like process on azo dye removal was evaluated under different operating conditions (pH, contact time, hydrogen peroxide concentration, and dye concentration). The concentration of the studied dye was measured using a spectrophotometer.
Results: The results of this study showed that the heterogeneous Fenton-like process in the presence of zero-valent iron particles can remove 97.3% of azo dye with the intital concentration of 50 mg/L at an initial pH of 6, hydrogen peroxide concentration of 6 mmol/L, and Fe particles dose of 0.5 g/L within 10 min of contact time.
Conclusion: In this study, it was found that azo dye can be effectively removed from the aqueous solution by heterogeneous Fenton method. Therefore, applictaion of zero-valent iron particles in the Fenton process is recommended for the effective removal of organic pollutants, especially dyes, from the aquatic environment.

 

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Introduction: Nitrate, due to its high solubility in water, causes pollution of groundwater resources, poses a serious threat to human health and causes eutrophication of water resources. The aim of this study was to optimize the use of modified pumice in the removal of nitrate from water.
Methods: This experimental study was performed in 2020 on laboratory scale. The experiments were designed using the Box-Benken method. The studied variables included pH (2-4), initial nitrate concentration (50-100 mg/L), contact time (15-45 min) and pumice dose (0.5 - 1.5 gr/L) at three levels. Thus, a total of 29 experiments were designed and performed. Experimental design and statistical analysis were performed using Design Expert 7.0 software. All examinations were performed according to the instructions provided in the latest edition of the Standard Methods for the Examinations of Water and Wastewater.
Results: The results showed that the quadratic polynomial equation fitted well with the experimental data. Also, the liner effects of all four variables (including pH, initial nitrate concentration, contact time and modified pumice dose), as well as interactions effects and quadratic effects of each variable on the nitrate removal efficiency from water were significant (P-Value <0.05). The results of numerical optimization showed that the optinal conditions included pH of 2.01, initial nitrate concentration of 70.45 mg/L, reaction time of 44.98 min, and modified pumice dose of 1.21 gr/L. Under these conditions, nitrate removal efficiency, model desirability, and predicted R² were 89.66%, 100% and 0.82, respectively.
Conclusion: According to the results, magnesium-modified pumice can be applied to remove nitrate from water. However, it should be mentioned that the pH of the water, after purification, must be modified with a suitable alkaline substance.
 

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Objective Among the pollutants in water sources, heavy metals are of great concern due to their non-biodegradability characteristics, their ability to accumulate in the food chain, and their adverse and chronic effects on human health. Therefore, this study aims to assess the health risk of exposure to heavy metals through drinking water in Bandar Abbas, Iran.
Methods This descriptive-analytical study was performed on drinking water samples in Bandar Abbas, Iran in 2020. Forty-two samples were taken from the drinking water distribution networks, the point-of-use water treatment devices, and municipal water treatment centers. Heavy metal concentrations in the samples were measured using the inductively coupled plasma mass spectrometry method. The carcinogenic risk of heavy metals was assessed according to probabilistic risk assessment method and Monte Carlo simulation technique.
Results The mean concentrations of arsenic, nickel, lead, and cadmium in drinking water were 1.25, 0.0713, 1.28, and 0.0005 µg/L, respectively. The mean carcinogenic risks of the mentioned metals were 1.23×10-4, 8.89×10-5, 2.07×10-4, and 2.23×10-4, respectively.
Conclusion The average concentrations of heavy metals in drinking water of Bandar Abbas city and their risks, except for arsenic, were lower than the standard level. Although the concentrations and risk levels showed no significant threat for the consumers, more studies are needed especially on the arsenic concentration.

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Objective Gastrointestinal (GI) cancers are common cancers in Iran. This study aims to investigate the relationship of simultaneous tobacco and opium use on the risk of GI cancers.
Methods This is a case-control study that was conducted on 60 people with GI cancers and 120 healthy peers in East of Hormozgan, south of Iran, in 2019. The data was collected by a questionnaire surveying demographic information, information about the type of cancer and family history of the disease, and information about the history of opium use and tobacco consumption in the last ten years. Chi-square and Fisher’s exact test were used to evaluate the difference in characteristics between the two groups. Also, logistic regression analysis was used to the relationship of tobacco and opium use with GI cancers.
Results The results showed that tobacco and opium use greatly increased the risk of GI cancers. Th odds ratios (OR) in people with only cigarette smoking (OR=5.08), only hookah smoking (OR=17.71), only opium use (OR=31.05), simultaneous opium and hookah use (OR=65.81), simultaneous opium and cigarette use (OR=77.08) and simultaneous cigarette, hookah, and opium use (OR=110.74) increased significantly (P<0.05).
Conclusion There is a significant relationship between simultaneous opium and tobacco use and GI cancer development. By identifying the risk factors of GI cancers, the findings of this study can help prevent these diseases in the study area.