Geographical distribution of nitrate pollution and its risk assessment using GIS and Monte Carlo simulation in drinking water in urban areas of Fars province-Iran during 2017-2021.

Pollution of water resources with nitrate is currently one of the major challenges at the global level. In order to make macro-policy decisions in water safety plans, it is necessary to carry out nitrate risk assessment in underground water, which has not been done in Fars province for all urban areas. In the current study, 9494 drinking water samples were collected in four seasons in 32 urban areas of Fars province in Iran, between 2017 and 2021 to investigate the non-carcinogenic health risk assessment. Geographical distribution maps of hazard quotient were drawn using geographical information system software. The results showed that the maximum amount of nitrate in water samples in 4% of the samples in 2021, 2.5% of the samples in 2020 and 3% of the samples in 2019 were more than the standard declared by World Health Organization guidelines (50 mg/L). In these cases, the maximum amount of nitrate was reported between 82 and 123 mg/L. The HQ values for infants did not exceed 1 in any year, but for children (44% ± 10.8), teenagers (10.8% ± 8.4), and adults (3.2% ± 1.7) exceeded 1 in cities, years, and seasons, indicating that three age groups in the studied area are at noticeably significant non-carcinogenic risk. The results of the Monte Carlo simulation showed that the average value of non-carcinogenic risk was less than 1 for all age groups. Moreover, the maximum HQ values (95%) were higher than 1 for both children and teenager, indicating a significant non-carcinogenic risk for the two age groups.

Distributing and assessing fluoride health risk in urban drinking water resources in Fars Province, Iran, using the geographical information system.

Excessive fluoride intake has been reported in many studies, which can lead to diseases such as autism, mental retardation, low birth weight, reproductive disorder, as well as dental and bone fluorosis. The potential risk assessment of fluoride intake for the health of people living in Fars Province, Iran, is investigated. Hence, 1700 drinking water samples were taken from April 2018 to March 2020 in four seasons in 29 cities of Fars Province and were analyzed. Non-carcinogenic health risks of exposure to fluoride through drinking water were evaluated. Moreover, the spatial distribution maps of fluoride and hazard quotient (HQ) risk index were prepared using GIS software. The results showed that the concentration of fluoride in the drinking water of the studied area was in the range of 0.086 to 2.61 mg/L. Accordingly, in 48.27% of the cities, fluoride was in the range below the national and international standards, 34.48% of the cities were in the permissible range of 0.5 to 1.5 mg/L, and 17.24% of the urban areas of the province had fluoride contents above the permissible range. Hazard quotient index had the health risk of HQ > 1 in 27.58% of children, 17.24% of teenagers, and 10.34% of adults in the urban areas of Fars Province. In the cities with HQ > 1, there was risk of diseases associated with excessive fluoride intake. Therefore, it is necessary to replace water supply sources in these cities.

Determination of bacterial and fungal bioaerosols in municipal solid-waste processing facilities of Tehran.

PURPOSE: The concentration and distribution characteristics of airborne bacteria and fungi were assessed at municipal solid-waste processing and disposal facilities (SWPDFs) of Tehran (Arad Kouh Site). METHODS: Air samples were obtained from the indoor air of a laboratory and refectory as well as from the air surrounding a conveyor belt, rotary screen, and bailer. Sampling was conducted according to the standard procedure to determine two bacterial species (Klebsiella spp. and Staphylococcus aureus), total bacteria and fungi, and Aspergillus fumigates. RESULTS: The maximum concentration of Staphylococcus aureus was in the air surrounding the conveyer belt with the average of 993.2 CFU/m3. The highest concentrations of total fungi (4958.8 CFU/m3) and Aspergillus fumigates (2114 CFU/m3) were measured in the air surrounding the rotary screen. The mean concentrations of bacterial bioaerosols in a more contaminated sampling location in summer and winter were 1687.6 and 1479.4 CFU/m3, respectively. CONCLUSIONS: There were significant differences between the concentration of bioaerosols in cold and warm seasons. The concentrations of bioaerosols in the air surrounding the rotary screen and conveyer belt were significantly more than those in other sampling locations, but were within the recommended maximum of 103 and 104 CFU/m3.

Proinflammatory effects of dust storm and thermal inversion particulate matter (PM10) on human peripheral blood mononuclear cells (PBMCs) in vitro: a comparative approach and analysis.

Particulate matter (PM) as the carcinogenic air pollutants can lead to aggravated health outcomes. Epidemiological studies demonstrated that PM can be engaged in different diseases such as cardiovascular, respiratory and cancer. The in vitro secretion of proinflammatory cytokines by human peripheral blood mononuclear cells (PBMCs) has been used to assess the effects of PM with an aerodynamic diameter < 10 µm (PM10). This study compared the proinflammatory cytokines tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), and interleukin 1-beta (IL1-ß) secretions of PBMCs exposed to PM10 of dust storm and inversion. We collected PM10 samples during the spring and autumn seasons in two locations. Isolated PBMCs were exposed separately to 50, 150, and 300 µg/ml of different type of PM10 for 4 and 24 h. The mean concentrations of TNF-α for the PM of dust storm and inversion were 6305.61 ± 2421 and 6651.74 ± 2820, respectively. Also the mean concentrations of IL1-ß for the PM of dust storm and inversion were 556.86 ± 162 and 656.35 ± 196, respectively. Furthermore, these values for the production of IL-6 were 12,655 ± 5661 and 16,685 ± 8069, respectively. Although no significant difference was observed between the PM of dust storm and that of inversion with regard to PBMCs, the results showed a significant increase in the proinflammatory cytokine secretion of both PMs compared with the controls. Moreover, TNF-α, IL1-ß, and IL-6 secreted in cells exposed to PM10 of dust storm were about 10 times more than the controls, these values for cells exposed to PM10 of inversion were around 10, 12, and 14 times more than the controls, respectively. It can be concluded that the PM10 of both dust storm and inversion can play a significant role in proinflammatory cytokine secretion due to its harmful effect on human health. Graphical abstractThis picture shows the Proinflammatory cytokine producing potential of PM10 with two sources (dust storm and urban air pollution) in exposure with human PBMCs in vitro.

Correction to: Investigation and Comparison of In Vitro Genotoxic Potency of PM10 Collected in Rural and Urban Sites at Tehran in Different Metrological Conditions and Different Seasons.

The original version of this article unfortunately contained a mistake. Figure 6 caption should be "The light microscopic image (a) and transmission electron microscopic image (b) of A549 cell after 24 h of exposure to PM10 (150 µg/ml).

Investigation and Comparison of In Vitro Genotoxic Potency of PM10 Collected in Rural and Urban Sites at Tehran in Different Metrological Conditions and Different Seasons.

The particulate matter has become a serious health problem in some large cities in the world. These particles are a complex mixture of chemical compounds which change based on location and time and, consequently, can cause different health-related effects. The exact mechanism of the effect of these particles is not yet known for certain. However, it seems that numerous mechanisms through the production of ROS and, eventually, DNA destruction, which are related to a wide range of diseases, are among the causes of particles' health-related effects. The present study is aimed to evaluate and compare the genotoxicity potential of particles collected in Tehran, Iran, in urban and rural regions during spring and autumn as well as dusty and inversion conditions. These effects were examined using the comet assay on human pulmonary epithelial cells (A549). Results showed that all the particles had the potential for genotoxicity at the concentration used in this study (75,150 and 300 µg/ml). Moreover, DNA destruction changed with season, site, and even dusty and inversion atmospheric conditions. These changes mostly belonged to urban particles. In general, urban particles in autumn and, specifically, on days with inversion had higher genotoxicity (p < 0.01). Difference was observed between dusty and regular days so that regular days were more potent (p < 0.05). A strong correlation was observed between the effects of most PAH compounds and other metals such as Cr, Co, Cd, Mn, As, and also SO4, which were mostly the result of combustion in vehicle engines in urban regions. No difference was observed for rural particles at different conditions and seasons.

Data on bioassay of toxicity reduction of treated textile wastewater by using nanophotocatalytic process by Daphnia magna.

Practicability and possibility of photocatalytic degradation of Ro16 textile dye and the actual wastewater of textile were studied on pilot scale. The amount of reduction in solution toxicity was studied and assessed by the application of a bioassay using Daphnia magna. The solution toxicity at the beginning of the process has an increasing procedure and this is caused by the intermediate products that are produced during the photocatalytic process from the mother compounds, and are more toxic compared to them, and their toxicity declines at the end of the process with the completion of mineralization. The procedure of toxicity increase and its decrease in the course of photocatalytic process has a direct relation with the amount of mineralization.

Short-term effects of particle size fractions on lung function of late adolescents.

Although ambient air pollution has been linked to reduced lung function in healthy students, longitudinal studies that compare the response of asthmatic and healthy adolescents are lacking. To evaluate lung function responses to short-term ambient air particulate matter (PM10, PM2.5, and PM1) levels, we conducted a study on high school students aged 15-18 years. The aim of this study was to assess effects of acute exposure to ambient air particulate matter (PM) on lung function in healthy and asthmatic late adolescents. We examined associations of lung function indices and ambient PM levels in 23 asthmatic and 23 healthy students. Paired-samples T test was used to evaluate the association of exposure to airborne PM concentrations with lung function test results (FVC, FEV1, FEV1/FVC, and FEF25-75). We observed negative impact of exposure to an increased concentration of ambient air PM10, PM2.5, and PM1 on lung function parameters of asthmatic and healthy late adolescents. These findings are consistent with other similar short-term studies which have confirmed the adverse effect of PM air pollution. These associations were stronger in asthmatic subjects compared with those in healthy ones. There are significant adverse effects of ambient air PM on pulmonary function of adolescents, especially asthmatics.

Physiochemical characteristics and oxidative potential of ambient air particulate matter (PM10) during dust and non-dust storm events: a case study in Tehran, Iran.

In the present study, we investigated the characteristics of metal(loid)s, polycyclic aromatic hydrocarbons (PAHs) and oxidative potential (OP) in PM10 during dust and non-dust days in a rural and an urban area in Tehran. Water-soluble ions, metal(loid)s, PAHs, and OP were measured using ion chromatography (IC), inductively coupled plasma optical emission spectrometer (ICP-OES) and gas chromatography/mass spectrometry (GC-MS), and dithiothreitol (DTT) assay respectively. The results showed that the average concentrations of ambient PM10 were 284 ± 90.4 and 123 ± 31.4 µg m-3 on dusty and regular days in urban areas respectively, and were 258 ± 48.3 and 124 ± 41.4 µg m-3 on dusty and regular days in rural areas, respectively; these values were 95% above the World Health Organization (WHO) guideline level. The crustal elements Na+, Mg2+, Ca2+, Al, Si, Fe and Ti were the dominant for PM10 on dusty days, and NO- 3 and SO4 2- were dominant for PM10 on regular days. The average ± SD concentrations of total PAHs were 34.3 ± 22.5 and 55.1 ± 28.3 ng m-3 on dusty and regular days, respectively, with the maximum value occurring on inversion days. The average OP was 8.90 ± 7.15 and 1.41 ± 0.35 and was 11.4 ± 3.97 and 19.9 ± 8.67 (nmol min-1 µg PM10 -1) for water and methanol extracts on dusty and regular days, respectively, with the lowest value occurring on dusty days. The OP was highly associated with Cu and Mn. Briefly; the results of this study demonstrate that OP is mass independent and consequence a promising proxy for PM mass.

Application of Epstein-Barr Virus for Optimization of Immortalized B-lymphocyte Production as a Positive Control in Genetic Studies.

BACKGROUND: Infection of B-cells with Epstein-Barr virus (EBV) leads to more and subsequent immortalization. This is considered as the method of choice for generating lymphoblastoid cell lines (LCLs). Producing LCLs, although very useful but is very time consuming and troublesome, drives the requirement for quicker and more reliable methods for EBV-driven B-cell transformation. MATERIALS AND METHODS: After successfully production of LCLs, different parameters including temperature, serum concentration, type of culture medium, and CO2 concentration were evaluated on EBV-transformed B-cells. In this study, we were able to produce LCLs and optimize condition. RESULTS: The best condition for generating LCLs was 37°C, 5% CO2, 20% fasting blood sugar, and RPMI 1640. The study results were to establish a reliable method for producing LCLs that can be used to produce immortalized B-cells from almost any sources. CONCLUSION: This can help with tumorgenecity studies, as well as producing control material for rare genetic disorders and so on. The aim of this study was to determine optimized condition for reliable and reproducible LCLs from different sources.

Displacement-dispersive liquid-liquid microextraction based on solidification of floating organic drop of trace amounts of palladium in water and road dust samples prior to graphite furnace atomic absorption spectrometry determination.

A new displacement-dispersive liquid-liquid microextraction method based on the solidification of floating organic drop was developed for separation and preconcentration of Pd(ll) in road dust and aqueous samples. This method involves two steps of dispersive liquid-liquid microextraction based on solidification. In Step 1, Cu ions react with diethyldithiocarbamate (DDTC) to form Cu-DDTC complex, which is extracted by dispersive liquid-liquid microextraction based on a solidification procedure using 1-undecanol (extraction solvent) and ethanol (dispersive solvent). In Step 2, the extracted complex is first dispersed using ethanol in a sample solution containing Pd ions, then a dispersive liquid-liquid microextraction based on a solidification procedure is performed creating an organic drop. In this step, Pd(ll) replaces Cu(ll) from the pre-extracted Cu-DDTC complex and goes into the extraction solvent phase. Finally, the Pd(ll)-containing drop is introduced into a graphite furnace using a microsyringe, and Pd(ll) is determined using atomic absorption spectrometry. Several factors that influence the extraction efficiency of Pd and its subsequent determination, such as extraction and dispersive solvent type and volume, pH of sample solution, centrifugation time, and concentration of DDTC, are optimized.

A novel method for high preconcentration of ultra trace amounts of B1, B2, G1 and G2 aflatoxins in edible oils by dispersive liquid-liquid microextraction after immunoaffinity column clean-up.

In the present study, a new approach which uses immunoaffinity column clean-up combined with dispersive liquid-liquid microextraction (DLLME) is proposed for the preconcentration of ultra trace amounts of aflatoxins (B1, B2, G1 and G2). The aflatoxins are then determined using a high-performance liquid chromatography coupled with fluorescent detector. Samples are extracted by immunoaffinity column (IAC) clean-up, and their eluents are used as dispersants of the subsequent DLLME, for further enrichment of aflatoxins. Various parameters (the type of elution solvent, the type and volume of extraction solvent and disperser solvent, extraction time, and centrifugation time) that affect the efficiency of the two steps are optimized. Under the optimum conditions (extraction solvent: 120 µL of chloroform, disperser solvent: 500 µL of acetonitrile, sample pH: 7.4, centrifugation time: 3 min), the calibration for B1, B2, G1 and G2 was found to be linear with coefficient of estimation (R²) of 0.9994, 0.9976, 0.9989, 0.9973 respectively and the limit of detection (LOD) was between 1.1 × 10⁻4 to 5.3 × 10⁻³ ng mL⁻¹ (3σ(b)/m, n=9). The recoveries at the two spiked levels ranged from 96.0 to 110.0% and the relative standard deviation (RSD) was less than 7.8% (n=9). The results show that dispersive liquid-liquid microextraction combined with HPLC is a selective, simple, sensitive, and effective analytical method for the preconcentration and determination of ultra trace amounts of aflatoxins. The proposed method was applied for preconcentration and determination of B1, B2, G1 and G2 aflatoxin in edible oils. Analysis of aflatoxins in FAPAS test material showed that the proposed method has good accuracy.

Determination of fluoride concentration in powdered milk in Iran 2010.

High concentrations of fluoride (F) in powdered milk (formula milk) can have adverse health effects on the body. The F concentration in powdered milk was analysed in Iran in 2010. A total of twelve commercial brands of highly consumed powdered milk were selected to analyse the F content through the standard F ion-selective electrode method. From each brand, three samples with different production dates were selected. The means and standard deviation for F concentration in all the samples was 1·73 (sd 0·3) µg F/g. The minimum and maximum F content in powdered milk brands Humana2 and Humana3 was 1·32 (sd 0·1) and 2·36 (sd 0·3) µg F/g, respectively. The study revealed that there was no significant difference in F concentration in the samples that belonged to various dates. Humana3 had a high F concentration (with an average of 2·36 (sd 0·3) µg F/g), which can be a risk factor for increased dental fluorosis, especially when being prepared using water with a high content of F.

Ultrasound-assisted emulsification solidified floating organic drops microextraction of ultra trace amount of Te (IV) prior to graphite furnace atomic absorption spectrometry determination.

In the present study, a new, simple and efficient method for the preconcentration of ultra trace amounts of Te (IV) is developed using ultrasound-assisted emulsification solidified floating organic drops microextraction (USAE-SFODME) before graphite furnace atomic absorption spectrometry determination. In this method, tellurium is extracted into the fine droplets of 1-undecanol after chelate formation with the water soluble ligand, ammonium pyrrolidinedithiocarbamate (APDC). Several factors such as pH, chelating agent amount, type and volume of the extracting solvent, sonication and centrifuging time that influence the extraction and complex formation are optimized. Under the optimum conditions, the calibration graph is linear in the range of 0.01-0.24ngmL(-1) of tellurium in the original solution, with limit of detection of 0.003ngmL(-1). The relative standard deviation (RSD) for seven replicated determinations of tellurium ion at 0.08ngmL(-1) concentration level is calculated as 3.4%. The proposed method was successfully applied to the determination of Te (IV) in a standard soil and several water samples.