Examining the relationship between land use and childhood leukemia and lymphoma in Tehran.

We conducted a hospital-based case-control study to explore the association between proximity to various land use types and childhood leukemia and lymphoma. This research involved 428 cases of childhood leukemia and lymphoma (2016-2021), along with a control group of 428 children aged 1-15 in Tehran. We analyzed the risk of childhood cancer associated with land use by employing logistic regression adjusted for confounding factors such as parental smoking and family history. The odds ratio (OR) for children with leukemia and lymphoma residing within 100 m of the nearest highway was 1.87 (95% CI = 1.00-3.49) and 1.71 (95% CI = 1.00-2.93), respectively, in comparison to those living at a distance of 1000 m or more from a highway. The OR for leukemia with exposure to petrol stations within 100 m was 2.15 (95% CI = 1.00-4.63), and for lymphoma it was 1.09 (95% CI = 0.47-2.50). A significant association was observed near power lines (OR = 3.05; 95% CI = 0.97-9.55) within < 100 m for leukemia. However, no significant association was observed between power lines and the incidence of childhood lymphoma. There was no association between bus stations, major road class 2, and the incidence of childhood leukemia and lymphoma. In conclusion, our results suggest a possible association between the incidence of childhood leukemia and proximity to different urban land uses (i.e., highways and petrol stations). This study is the first step in understanding how urban land use affects childhood leukemia and lymphoma in Tehran. However, comprehensive studies considering individual-level data and specific pollutants are essential for a more nuanced understanding of these associations.

Association of Lactobacillus, Firmicutes, Bifidobacterium, Clostridium, and Enterococcus with colorectal cancer in Iranian patients.

Background: Colorectal cancer (CRC) is one of the primary causes of cancer-associated deaths worldwide, and growing evidence shows that alteration in the gut microbiota may be a contributing factor to the development and progression of the disease. This study investigates the correlation between CRC and specific intestinal microbiota abundance, including Firmicutes, Lactobacillus, Enterococcus, Clostridium, and Bifidobacterium. Material and methods: In this study, 100 CRC samples and adjacent normal tissues were obtained from Iranian patients. Afterward, we assessed the abundance of the mentioned bacteria in matched tumor and normal tissue samples from 100 CRC patients, by TaqMan quantitative real-time polymerase chain reaction (qPCR). Results: Most of the patients (55 %) had grade II cancer (moderately differentiated), followed by grade III (poorly Differentiated) in 19 %, and the distribution of the tumor location was 65 % in the colon and 35 % in the rectum. Our research showed a substantial difference in the relative abundance of specific bacteria in tumors and healthy tissues. To this end, four genera of bacteria, including Bifidobacterium, Lactobacillus, Clostridium, and Firmicutes, exhibited statistically significant reductions in tumor tissues compared to adjacent normal tissue (p < 0.05). Conversely, Enterococcus demonstrated a statistically significant increase in tumor tissue samples (p < 0.05). Noteworthy, statistical analysis revealed a significant relationship between Enterococcus and prior cancer (p < 0.05). Conclusions: These findings provide significant insight into the complex association between the gut microbiota and CRC and may pave the way for future research on novel screening methods, preventive measures, and therapeutic strategies targeting the gut microbiota in CRC patients.

Assessment of the risk of Legionella pneumophila in water distribution systems in hospitals of Tehran city.

When a sensitive host inhales aerosols containing these bacteria, Legionella infection occurs. Therefore, monitoring and assessing Legionella in the environment and water distribution systems of such places are critical due to the prone population in hospitals. However, the health risks of Legionella bacteria in the environment are not adequately evaluated. In this study, for hospitalized patients, we performed a quantitative health risk assessment of Legionella in selected hospitals in Tehran city using two scenarios of shower and toilet faucet exposure. This study identified Legionella in 38 cases (38%) out of 100 samples collected from toilet faucets and showers in 8 hospitals. The information gathered was used for quantitative microbial risk assessment (QMRA). The microbial load transmitted by inhalation was calculated using the concentration of Legionella in water. Other exposure parameters (inhalation rate and exposure time) were obtained using information from other studies and the median length of hospital stay (3.6 days). The exponential model was used to estimate the risk of infection (γ = 0.06) due to Legionella pneumophila (L. pneumophila) inhalation for each exposure event. For the mean concentration obtained for Legionella (103 CFU/L), the risk of infection for toilet faucets and showers was in the range of 0.23-2.3 and 3.5-21.9, respectively, per 10,000 hospitalized patients. The results were compared with the tolerable risk level of infection determined by the US EPA and WHO. The risk values exceeded the WHO values for waterborne pathogens in hospitals in both exposure scenarios. As a result, our QMRA results based on monitoring data showed that despite using treated water (from distribution networks in the urban areas) by hospitals, 38% of the samples were contaminated with Legionella, and faucets and showers can be sources of Legionella transmission. Hence, to protect the health of hospitalized patients, the risk of Legionella infection should be considered.

Potential cytotoxicity of trace elements and polycyclic aromatic hydrocarbons bounded to particulate matter: a review on in vitro studies on human lung epithelial cells.

A large number of studies have been conducted for clarifying toxicological mechanisms of particulate matter (PM) aimed to investigate the physicochemical properties of PM and providing biological endpoints such as inflammation, perturbation of cell cycle, oxidative stress, or DNA damage. However, although several studies have presented some effects, there is still no consensus on the determinants of biological responses. This review attempts to summarize all past research conducted in recent years on the physicochemical properties of environmental PM in different places and the relationship between different PM components and PM potential cytotoxicity on the human lung epithelial cells. Among 447 papers with our initial principles, a total of 50 articles were selected from 1986 to April 2020 based on the chosen criteria for review. According to the results of selected studies, it is obvious that cytotoxicity in human lung epithelial cells is created both directly or indirectly by transition metals (such as Cu, Cr, Fe, Zn), polycyclic aromatic hydrocarbons (PAH), and ions that formed on the surface of particles. In the selected studies, the findings of the correlation analysis indicate that there is a significant relationship between cell viability reduction and secretion of inflammatory mediators. As a result, it seems that the observed biological responses are related to the composition and the physicochemical properties of the PMs. Therefore, the physicochemical properties of PM should be considered when explaining PM cytotoxicity, and long-term research data will lead to improved strategies to reduce air pollution.

Association between colorectal cancer and Fusobacterium nucleatum and Bacteroides fragilis bacteria in Iranian patients: a preliminary study.

BACKGROUND AND AIM: Recent studies have proposed that commensal bacteria might be involved in the development and progression of gastrointestinal disorders such as colorectal cancer (CRC). Therefore, in this study, the relative abundance of Fusobacterium nucleatum, Bacteroides fragilis, Streptococcus bovis/gallolyticus, and Enteropathogenic Escherichia coli (EPEC) in CRC tissues, and their association with clinicopathologic characteristics of CRC was investigated in Iranian patients. Moreover, the role of these bacteria in the CRC-associated mutations including PIK3CA, KRAS, and BRAF was studied. METHOD: To these ends, the noted bacteria were quantified in paired tumors and normal tissue specimens of 30 CRC patients, by TaqMan quantitative Real-Time Polymerase Chain Reaction (qPCR). Next, possible correlations between clinicopathologic factors and mutations in PIK3CA, KRAS, and BRAF genes were analyzed. RESULTS: In studied samples, B. fragilis was the most abundant bacteria that was detected in 66 and 60% of paired tumor and normal samples, respectively. Furthermore, 15% of the B. fragilis-positive patients were infected with Enterotoxigenic B. fragilis (ETBF) in both adenocarcinoma and matched adjacent normal samples. F. nucleatum was also identified in 23% of tumors and 13% of adjacent normal tissue samples. Moreover, the relative abundance of these bacteria determined by 2-ΔCT was significantly higher in CRC samples than in adjacent normal mucosa (p < 0.05). On the other hand, our findings indicated that S. gallolyticus and EPEC, compared to adjacent normal mucosa, were not prevalent in CRC tissues. Finally, our results revealed a correlation between F. nucleatum-positive patients and the KRAS mutation (p = 0.02), while analyses did not show any association between bacteria and mutation in PIK3CA and BRAF genes. CONCLUSION: The present study is the first report on the analysis of different bacteria in CRC tissue samples of Iranian patients. Our findings revealed that F. nucleatum and B. fragilis might be linked to CRC. However, any link between gut microbiome dysbiosis and CRC remains unknown.

Exposure to heavy metal contamination and probabilistic health risk assessment using Monte Carlo simulation: a study in the Southeast Iran.

The rice contamination to heavy metals and its associated health risks have been less addressed in the southeast of Iran. In the present study, in the mentioned region, we assessed the concentration of nine elements in rice, and the health risk related to the measured elements was determined using the data which were gathered by a questionnaire. For this purpose, 36 samples of the 12 most widely consumed rice brands were collected. Using ICP-MS, the concentrations of Ni, Cr, Hg, Sr, Mn, Fe, Se, Ba, and Zn were measured in the studied samples as 0.599 ± 0.124, 0.483 ± 0.28, 0.0157 ± 0.005, 0.85 ± 1.307, 11.5 ± 1.97, 178.46 ± 67.27, 0.212 ± 0.083, 0.845 ± 0.62, and 8.416 ± 1.611 mg/kg, respectively. We found that, regarding the other studies, the levels of Ni, Cr, Hg, Fe, and Ba were higher. Besides, using 258 distributed questionnaires among citizens, the daily rice consumption was determined to be 295.66 ± 171.005 g/person/ day. Based on this consumption rate and Monto Carlo uncertainty simulation, Fe (0.741 ± 0.54 mg/kg/day) and Se (8.95E-04 ± 6.33E-04 mg/kg/day) showed the highest and lowest daily intake, respectively. Also, using Hazard Quotient (HQ), the non-carcinogenic risk effects of the surveyed elements were estimated. The obtained results of HQ revealed that Fe (2.48) and Mn (1.06) could pose non-carcinogenic health risks to consumers. Moreover, the calculated hazard Index showed that the overall health risk of the surveyed elements is in an unsafe range.

Degradation of furfural in aqueous solution using activated persulfate and peroxymonosulfate by ultrasound irradiation.

Furfural is a toxic compound that can cause many problems for human health and the environment. In this study, we addressed the degradation of furfural in aqueous solution using the activated persulfate (SPS) and peroxymonosulfate (PMS) through the ultrasonic (US) wave. Besides, the effect of various parameters (pH, oxidizing dose, initial furfural concentration, US frequency, Inorganic anions concentration, and scavenger) on SPS + US (SPS/US) and PMS + US (PMS/US) processes were examined. The results showed, in order to furfural removal, the US had excellent efficiency in activating SPS and PMS, as in SPS/US and PMS/US processes, 95.3% and 58.4% of furfural (at 25 mg/L concentration) was decomposed in 90 min, respectively. The furfural degradation rate increased with increasing oxidizing dose and US frequency in both SPS/US and PMS/US processes. Considering the synergistic effect, the best removal rate has occurred in the SPS/US process. In the SPS/US and PMS/US processes, furfural removal increased at natural pH (pH 7), and the presence of inorganic anions such as NO3- and Cl- had negative effects on furfural removal efficiency. Also CO32- and HCO3- acted as a radical scavenger in the SPS/US process but these anions in the PMS/US process produced more SO4-° radicals, and subsequently, they increased the furfural degradation rate. The results also showed that the predominant radical in the oxidation reactions is the sulfate radical. This study showed that the SPS/US and PMS/US processes are promising methods for degrading organic pollutants in the environment.

An overview report on the application of heteropoly acids on supporting materials in the photocatalytic degradation of organic pollutants from aqueous solutions.

Organic pollutants contaminate water resources and the environment when discharged into water streams. Also, the presence of these materials in incompletely treated or untreated wastewater leads to serious environmental hazards. The hydroxyl radicals and holes are regarded as the most oxidant species in the degradation of organic pollutants using the studied composites. The results of this review show that heteropoly acids on supporting materials could be considered as appropriate photocatalysts in the removal of organic pollutant from aqueous solutions.

Quantitative and qualitative analysis of dental clinics waste in Zabol city, Iran.

Dental clinics are one of the sources of waste production that are important due to producing infectious and potentially infectious waste, chemical and pharmaceutical waste, and toxic waste. Therefore, this study aimed to analyze dental clinics in Zabol quantitatively and qualitatively. This descriptive cross-sectional study was conducted in 2014 on waste produced in dental clinics in Zabol. Sampling of 25 dental clinics was performed three times per week. At the end of the working day, the samples were transferred to a suitable site and weighed carefully after separation of the components. Data were analyzed using descriptive statistics and Excel software. 5457 kg of waste is annually produced in the dental clinics of Zabol that the amount of infectious and potentially infectious waste, household-like waste, chemical and pharmaceutical waste, and toxic wastes are approximately 48.08, 43.75, 7.82 and 0.35%, respectively. Given that proper management of waste produced is not performed in dental clinics in Zabol, special attention to waste produced in this sector through programs of reduction in source, separation and recycling can reduce the waste volume significantly.

Stochastic exposure and health risk assessment of rice contamination to the heavy metals in the market of Iranshahr, Iran.

An investigation of some heavy metals content in rice (Oryza sativa) and associated health risks was carried out for residents of Iranshahr city, Iran. Average daily rice consumption of the citizens and most widely used rice brands in the market of Iranshahr were determined using a questionnaire. Besides, the concentration of heavy metals in the gathered rice samples was measured by inductively coupled plasma mass spectrometry (ICP-MS). Monte Carlo uncertainty simulation was utilized in conducting exposure assessment and investigating the non-carcinogenic effects of the studied elements as well as the carcinogenic effect of As. Concentrations of As, Cd, Pb, Cu, Al, and Mo were 0.369 ±â€¯0.094, 0.0337 ±â€¯0.039, 0.123 ±â€¯0.14, 3.095 ±â€¯439.42, 39.6 ±â€¯14.73, and 1.106 ±â€¯0.133 mg kg-1, respectively. Al (0.18 ±â€¯0.15 mg kg-1 d-1) and Cd (0.00015 ±â€¯0.00034 mg kg-1 d-1) were the highest and lowest estimated daily intake, respectively. Except As (5.23 ±â€¯4.01), the calculated hazard quotient for investigated elements showed no non-carcinogenic health risk. Besides, the simulation of the carcinogenic risk effect for As (2.37E-3) revealed that the ingestion of the studied rice brands would cause cancer risk due to lifetime consumption. Results show that consumption of rice in the Iranshahr city is a potential source of exposure to the studied elements.

Degradation of Penicillin G by heat activated persulfate in aqueous solution.

We used Heat Activated of Persulfate (HAP) to decompose Penicillin G (PEN G) in aqueous solution. The effect of pH (3-11), temperature (313-353 K), and initial concentration of Sodium Persulfate (SPS) (0.05-0.5 mM) on the decomposition level of PEN G were investigated. The residue of PEN G was determined by spectrophotometry at the wavelength of 290 nm. Also, the Chemical Oxygen Demand (COD) was measured in each experiment. The Total Organic Carbon (TOC) analysis was utilized for surveying the mineralization of PEN G. In addition, based on Arrhenius equation, the activation energy of PEN G decomposition was calculated. The results indicated that the maximum PEN G removal rate was obtained at pH 5 and by increasing the doses of SPS from 0.05 to 0.5 mM, the PEN G decomposition was enhanced. It was found that an increase in temperature is accompanied by an increase in removal efficiency of PEN G. The activation energy of the studied process was determined to be 94.8 kJ mol-1, suggesting that a moderate activation energy is required for PEN G decomposition. The TOC measurements indicate that the HAP can efficiently mineralize PEN G. Besides, the presence of the scavengers significantly suppressed the HAP process to remove the PEN G. Overall, the results of this study demonstrate that using HAP process can be a suitable method for decomposing of PEN G in aqueous solutions.

UV Activation of Persulfate for Removal of Penicillin G Antibiotics in Aqueous Solution.

Penicillin G (PG) is one of the most widely consumed antibiotics around the world. Release of PG in environment may lead to contamination of water resources. The aim of the present work is to assess feasibility of applying UV-activated persulfate process in removal of PG from aquatic environments. The study examined the effect of pH (3-11), persulfate initial concentration (0.5-3 mM), reaction time (15-90 minutes), and initial concentration of PG (0.02-0.14 mM) on PG decomposition. Also, the pseudo-first-order kinetic model was used for kinetic analysis of PG removal. The results indicated that UV-activated persulfate process can effectively eliminate PG from water. The highest PG removal efficiency was obtained as 94.28% at pH 5, and the decomposition percentage was raised by increasing persulfate dose from 0.5 to 3 mM and the reaction time from 15 to 90 minutes. Besides, the removal efficiency decreased through increasing the initial concentration of PG. UV-activated persulfate process effectively decomposes PG and eliminates it from water.