Characterization of persistent materials of deposited PM2.5 in the human lung.

Clearance of deposited urban air particulates (PMs) from the lung is vital for the protection of the lung tissue. Several studies have investigated the behavior of immune cells against these particulates in vitro and in vivo. However, the fate of particulates in the lung is yet unclear. Here, we report the results of our investigations on the clearance of particulates from the lung. Twelve normal lung tissue samples were taken from nonsmoking and non-occupationally exposed patients who needed lung lobectomy or segmentectomy. The remaining particulates were isolated from the alveolar area and extracellular matrix (ECM), separately, and their chemical composition was determined using the FE-SEM EDAX and GC-MS. Moreover, urban air PM2.5 was collected in two forms dry and washed. These were characterized too. Our results showed that none of the metals in the deposited particulates structure is fully water-soluble. After contact with mucosal liquid, the alveolar particulates included Fe, Al, Si, Ti, and Ni. These elements were absent in the PMs isolated from ECM. The organics of alveolar and ECM particulates were the same and included tetra-decane, hexadecane, and octa-decane. None of the organics present in the urban air PM2.5, such as PAHs, were available in isolated particulates from the lung tissue. This study shows that the full clearance of inhaled particulates does not happen in the lung. The immune system's primary function is detoxification by removing all components identifiable by immune cells. After that, the remained PMs will be relocated and deposited into the ECM.

Development of a new method for isolation of urban air particulates deposited in the human lung tissue.

Particulate matters (PMs) are important pollutants in urban air pollution because of their variable composition. The pulmonary clearance of PMs is critical to prevent long-term immunological responses. This study established a new method for the isolation of probably deposited urban air particulates from the human lung tissue, to investigate the features of uncleared particulates. The lung samples were acellularized with SDS solution of various concentrations ranging from 1 to 10%to lyse cells and release the PMs. In addition, the extracellular matrix (ECM) that remained was digested by proteinase K enzyme. The results of this study demonstrated that an SDS solution of 4% is the optimum concentration for the isolation of settled PMs from the lung tissue. Moreover, the used enzymatic method could separate settled PMs from the lung ECM appropriately. The results exhibited that epithelial cells form 46% of the samples' weight on average, whereas just 20% of isolated PMs were found in this part of the tissue. Both groups of separated PMs tend to agglomerate, but it is significantly higher in cellular isolated PMs. The particles separated from ECM have an agglomeration tendency, which is observable only by FE-SEM imaging. Moreover, we found a major part of urban air PMs deposited in ECM. The established method in this study can be used in future investigations to isolate other types of PMs settled in the lung, such as occupationally inhaled carbonaceous particulates.

Particulates induced lung inflammation and its consequences in the development of restrictive and obstructive lung diseases: a systematic review.

Particulate matters (PMs) are significant components of air pollution in the urban environment. PMs with aerodynamic diameter less than 2.5 µm (PM2.5) can penetrate to the alveolar area and introduce numerous compounds to the pneumocystis that can initiate inflammatory response. There are several questions about this exposure as follows: does PM2.5-induced inflammation lead to a specific disease? If yes, what is the form of the progressed disease? This systematic review was designed and conducted to respond to these questions. Four databases, including Web of Science, Scopus, PubMed, and Embase, were reviewed systematically to find the related articles. According to the included articles, the only available data on the inflammatory effects of PM2.5 comes from either in vitro or animal studies. Both types of studies have shown that the induced inflammation is type I and includes secretion of proinflammatory cytokines. The exposure duration of longer than 28 weeks was not observed in any of the reviewed studies. However, as there is not a specific antigenic component in the urban particulate matters and based on the available evidence, the antigen-presenting is not a common process in the inflammatory responses to PM2.5. Therefore, neither signaling to repair cells such as fibroblasts nor over-secretion of extracellular matrix (ECM) proteins can occur following PM2.5-induced inflammation. These pieces of evidence weaken the probability of the development of fibrotic diseases. On the other hand, permanent inflammation induces the destruction of ECM and alveolar walls by over-secretion of protease enzymes and therefore results in progressive obstructive effects.

Associations between short term exposure to ambient particulate matter from dust storm and anthropogenic sources and inflammatory biomarkers in healthy young adults.

This study examined the association between particulate matter from anthropogenic and natural sources and inflammatory biomarkers, including hs-CRP, IL-6, sTNF-RII, and WBCs, in two groups of healthy young subjects. We followed up subjects of two panels (16 to 22 years old), including 22 subjects selected from the urban area (Tehran city) with high-level pollution background and 22 subjects selected from the rural area (Ahmadabad) with low-level pollution background. In each group, we collected 4 times blood samples in various air pollution conditions, In the subjects of the urban group, there was a substantial difference (p < 0.05) between inversion days and cold season control days, and between dust storm days and warm season control days for concentrations of hs-CRP, IL-6, and WBCs biomarkers. In the subjects of the rural group, a significant difference could be detected in the concentration of hs-CRP, IL-6, and WBCs biomarkers (p < 0.05) between inversion days and cold season control days, and between dust storm and warm control days. We found that the difference in concentrations of hs-CRP, IL-6, and WBCs biomarkers between dust storm days and warm control conditions in the rural group were higher than the difference in inversion and cold control conditions, which can be attributed to low background air pollution in the rural area. In the urban area, the health effect of anthropogenic sources of PM is higher than the dust storm condition, which can be attributed to the stronger effect of anthropogenic pollution effect.

Magnetic carnosine-based metal-organic framework nanoparticles: fabrication, characterization and application as arsenic adsorbent.

This study centers on the controllable synthesis, characterization, and application of a novel magnetic bio-metal-organic framework (Bio-MOF) for the adsorption and subsequent removal of arsenic from aqueous solutions. Zinc ions and carnosine (Car) were exploited to construct the Car-based MOF on the surface of magnetite (Fe3O4 NPs). The Magnetite precoating with Car led to an increase in the yield and the uniform formation of the magnetic MOF. The prepared magnetic Bio-MOF nanoparticles (Fe3O4-Car-MOF NPs) had semi-spherical shape with the size in the range of 35-77 nm, and the crystalline pattern of both magnetite and Car-based MOF. The NPs were employed as an adsorbent for arsenic (As) removal. The adsorption analyses revealed that all studied independent variables including pH, adsorbent dose, and initial arsenic concentration had a significant effect on the arsenic adsorption, and the adsorption data were well matched to the quadratic model. The predicted adsorption values were close to the experimental values confirming the validity of the suggested model. Furthermore, adsorbent dose and pH had a positive effect on arsenic removal, whereas arsenic concentration had a negative effect. The adsorption isotherm and kinetic studies both revealed that As adsorption fitted best to the Freundlich isotherm model. The maximum monolayer adsorption capacity (94.33 mg/g) was achieved at room temperature, pH of 8.5 and adsorbent dose of 0.4 g/L. Finally, the results demonstrated that the adsorbent could be efficiently applied for arsenic removal from aqueous environment.

Validity of a Serological Diagnostic Kit for SARS-CoV-2 Available in Iran.

BACKGROUND: The Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic broke out in December 2019 and is now characterized as a pandemic. Effective control of this infectious disease requires access to diagnostic techniques, for both case finding and epidemic size estimation. The molecular technique is routinely used worldwide. Although it is the "standard" case detection and management method, it has its own shortcomings. Thus, some easy-to-use rapid serological tests have been developed. METHODS: One hundred and fourteen positive RT-PCR-diagnosed patients were tested by VivaDiag Kit, a brand of rapid serological kits available in hospitals affiliated to Tehran University of Medical Sciences (TUMS), Tehran, Iran. Frozen serum specimens taken from healthy people in summer and fall 2019 were also tested as negative controls. RESULTS: Test sensitivity was 47.9% (95% confidence interval [CI]: 38.8-56.9) for IgM and 47.0% (95% CI: 38.0-56.0) for IgG. There was no difference between IgG and IgM seropositivity except in one case. Specificity was calculated as 99.0% (95% CI: 96.4-99.9) for IgM and of 100.0% (95% CI: 0.98.2-100.0) for IgG. Sensitivity was higher in men and older participants. CONCLUSION: This test can be used for epidemiological investigations, especially for the estimation of the level of infection in the community, after it is properly corrected for sensitivity and specificity. The low sensitivity could be attributed to the technical limitations of the kit or low levels of antibodies after infection. The different sensitivity in age and sex groups supports the hypothesis that different people show different immune responses to this virus.

The acute effects of short term exposure to particulate matter from natural and anthropogenic sources on inflammation and coagulation markers in healthy young adults.

Airborne particulate matter is associated with increasing the risk of cardiovascular diseases. The purpose of this study was to investigate the association between air pollution conditions and MDA, vWF, and fibrinogen markers in the blood of two panels of healthy young individuals in an urban area in Tehran city with a high air pollution background and another group was living in a rural area (Ahmad Abad Mostofi), with a low air pollution background. In each group, 4 blood samples were taken as follows: one in inversion days, the second in winter, but during the existence of normal condition in terms of air pollution, the third sample in the spring during the normal condition in terms of air pollution and the fourth sample during the dust storm conditions. In the urban and rural groups, there was a significant difference between the concentration of MDA, vWF, fibrinogen between inversion and cold season control conditions, and between dust storm conditions and warm season control conditions (p < 0.05). The results showed that the association of dust storm condition on the measured biomarkers was stronger than the inversion condition, which health consideration in the dust conditions be taken into account similar to the inversion conditions.

Environmental exposure to endotoxin and its health outcomes: A systematic review.

Exposure to endotoxin occurs environmentally and occupationally. There are several differences between them in terms of the variety and severity of health outcomes, possible exposed groups and type and route of exposure. Occupational exposures caused adverse health outcomes in almost all cases, but there is disparity in the incidence of significant health outcomes due to environmental exposure to endotoxin. This study has therefore endeavoured to investigate health outcomes from environmental exposure to endotoxin. A systematic review was conducted of three databases and non-occupational studies reporting the environmental concentration of endotoxin, and observed health outcomes in exposed groups were included in the review (n = 27). The studies showed that first exposure to endotoxin occurs in infancy by the inhalation route. Inhalation is the only exposure route that can induce inflammation as the main symptom of exposure to endotoxin. The studies included were conducted using four approaches: molecular immunology, measurement of lung volumes, clinical sensitisation test and diagnosis of asthmatic and respiratory symptoms such as wheezing. By the immunological approach, all the included studies reported that environmental exposure to endotoxin, especially at a younger age, has a protective effect on the incidence of asthma in adolescence. The main disparity observed was in studies using the approach of diagnosed asthma. Overall, however, they confirm the protective effect of exposure to endotoxin although, in the case of children with non-atopic asthma, the results could be different.

Monitoring of salt iodisation programme in Iran; Health outcomes, shortages and perspective.

Iodine deficiency disorders include a wide range of metabolic and nonmetabolic disorders including goiter. To control IDDs, the World Health Organization and responsible agencies in countries established daily iodine uptake. Almost all the countries in the world provide the required iodine through salt iodisation. IDDs are not completely eradicable, so monitoring the salt iodisation programme is necessary for control of IDDs. In Iran, a salt iodisation programme was started in 1996. In this study, we took salt samples from all legally produced salt brands in Iran in 30 provinces and measured iodine concentration. The results of the monitoring programme for iodine concentration in schoolchildren's urine was used to compare accessibility to iodized salts and health outcomes. The results show that more than 80% of available salts have a suitable or acceptable concentration of iodine. Despite large variance in iodine concentration in available salt in some provinces, the median of iodine concentration in salts is within an acceptable range. Also, the urinary concentration of iodine (national median = 161) confirms that shortage of iodine intake is very low in Iran. The high rate of salt consumption of the Iranian people also has a significant effect on iodine uptake, but can lead to hyperthyroidism and hypertension that must be controlled.

Assessment of the Health Risk Induced by Accumulated Heavy Metals from Anaerobic Digestion of Biological Sludge of the Lettuce.

Heavy metals are a group of pollutants in biological sludge. Many agencies regulated guidelines for heavy metal concentrations for various applications of sludge such as agricultural application. In this study, we tried to determine heavy metal fate after anaerobic digestion. Additionally, we determined the bioaccumulation rate of heavy metals in lettuce cultivated on a sludge-applied land. Heavy metal (As, Pb, Hg, Cd) contents of solid and liquid parts of raw and anaerobically digested sludge were separately measured by ICP-OES. For this purpose, the samples were digested using nitric acid, hydrochloric acid, and boric acid. Then, the raw and anaerobically digested sludge were used for cultivation of lettuce in separate farms. The heavy metal concentrations in the harvested lettuce were measured by the same procedure. The results showed that the main part of heavy metals in the raw sludge was in the liquid part (67%), while, the main part of heavy metals in the anaerobically digested samples was in the solid part of the sludge. Because of washout of dissolved heavy metals in the liquid part of the sludge, the lettuce cultivated by anaerobically digested sludge had higher content of the heavy metals in comparison to that of the lettuce cultivated by the raw sludge. This study showed that application of anaerobically digested sludge can increase the bioaccumulation rate of heavy metals in the crops and induce more human health risk.

Data on spot-kits versus titration method for iodine determination in salt: Performance and validity.

The aim of this data is comparison of achieved data from salt iodine measurement by titration method with using sodium thiosulfate in presence of lugol׳s reagent and commercial spot- kit. Titration measurement was carried out in two different laboratories using standard samples. 437 samples including 20 commercial brands were collected throughout Iran. The iodine contents of the samples were measured by both the titration method and two most frequently used spot-kit brands in Iran. There is no significant differences between the results obtained from the two brands of spot-kits (ICC = 0.797). The kits sensitivity for determination of negative samples was high (more than 0.9) but by increasing the iodine concentration up to 15 ppm, the kits' sensitivity was decreased. These findings indicate that the titration method is necessary for quantitative purposes, especially for concentrations higher than 30 ppm. However, spot-kits are suitable for qualitative and semi-quantitative measurements.

Measurement of microcystin -LR in water samples using improved HPLC method.

Microcystins are a group of toxic compounds produced by freshwater cyanobacteria and cause diseases. World Health Organization has recommended a concentration of 1 µg/l for Microcystin-LR (MC-LR) in potable water as guideline value. The high performance liquid chromatography (HPLC) followed by C18 analytical column and ultra violet detector for detection of MC-LR. In this regard, 5 different concentrations of MC-LR solutions were injected into HPLC. MC-LR was detected in 5.33 minute retention time and Calibration curve was achieved with R(2) = 0.988. Detection limit for this method was obtained by using acetonitrile solutions (32% and 55%) as a gradient run and a high silanol activity column equal to 0.02 µg /mL. Despite no acidic organic modifier being used in the mixture of solvents, the sensitivity of this method was appropriate for detection of MC-LR. Because of short retention time, reduction in number of solvents and high resolution and suitable sensitivity, this method is affordable and is fast for detection and determination of MC-LR in potable water.