Journal of Environmental Health Science and Engineering最新文献

Purpose

Lead, a known toxic metal, causes several adverse reproductive effects, including low birth weight. Fortunately, the exposure level has sharply decreased during the recent decades, but a definitive safe level did not introduce for pregnant women yet. The current meta-analysis study aimed to conduct a quantitative estimation of maternal and umbilical cord blood lead effects on birth weight.

Methods

Two researchers have independently searched the scientific literature for retrieving related studies using the PRISMA criteria for data extraction. Twenty-one full-text articles were selected from primary 5006 titles, limited by the English language and published between 1991 and 2020 on humans.

Results

The pooled mean of maternal and umbilical cord blood lead levels were 6.85 µg/dL (95% CI: 3.36–10.34) and 5.41 µg/dL (95%CI: 3.43–7.40), respectively. The correlation coefficient analysis showed a significant inverse association between the mean maternal blood lead level and birth weight, which was confirmed by Fisher Z-Transformation analysis (-0.374, 95% CI: -0.382, -0.365, p < 0.01). In addition, a significantly lower birth weight (∆: 229 gr, p < 0.05) was found in the relatively high level of maternal blood lead than in low-level exposure (> 5 µg/dL vs. ≤ 5 µg/dL, respectively).

Conclusion

In short, the present study findings suggest an increasing maternal blood lead levels could be a potential risk factor for reducing birth weight. Thus, pregnant women should avoid lead exposure, as much as possible.

Groundwater is one of the major sources of exploitation in arid and semiarid regions. Spatial and temporal quality distribution is an important factor in groundwater management. Thus for protecting groundwater quality, data production on spatial and temporal distribution is essential. The present study has applied multiple linear regression (MLR) techniques to predict the fitness of groundwater quality in Kermanshah province, west of Iran. The parameters examined were Total dissolved solids (TDS), Total hardness (TH), Sodium adsorption ratio (SAR). the quality variables were modelled by MLR. Finally, the performance of the models was assessed using the coefficient of determination (R²). The relationship between parameters by MLR showed that TDS and water quality parameters in semi-deep wells and aquifers had a strong positive correlation (r = 0.94, r = 0.98) and there was a strong positive significant correlation between SAR and water quality parameters in deep wells and aquifers (r = 0.98, r = 0.99). Also, TH and water quality parameters in all water sources had a strong positive correlation (r = 1). The MLR model could serve as an alternative and cost-effective tool for groundwater quality prediction where there is limitation in laboratory facilities, trained expertise or time. Consequently, the usefulness of these linear regression equations in predicting the groundwater quality is an approach, which can be applied in any other locations.

This study aims to assess the impact of using different fuels in Egyptian Titan Alexandria Portland Cement Company on emissions and concentrations of pollutants (Total suspended particles (TSP), nitrogen dioxide (NO₂‎), and sulfur dioxide (SO₂)) and their influence on ambient air quality during the period 2014–2020 using AERMOD dispersion model. The results showed that changing the fuel from natural gas in 2014 to coal mixed with alternative fuels (Tire-Derived Fuel (TDF), Dried Sewage Sludge (DSS), and Refuse Derived Fuels (RDF)) in 2015–2020 caused fluctuating variations in pollutant emissions and concentrations. The highest and lowest maximum concentrations of TSP occurred in 2017 and 2014 respectively, where the TSP is positively correlated with coal, RDF, and DSS and negatively correlated with natural gas, diesel, and TDF. Also, the lowest and highest maximum NO₂ concentrations were detected in 2020 and 2016 followed by 2017 respectively, where NO₂ is positively correlated with DSS and negatively correlated with TDF and varies with diesel, coal, and RDF. Moreover, the maximum concentrations of SO₂ were the lowest in 2018 and highest in 2016 followed by 2017 because of its considerable positive correlation with natural gas and DSS and negative correlation with RDF, TDF, and coal. Generally, it was found that increasing the percentage of TDF and RDF with decreasing the percentage of DSS, diesel, and coal will reduce pollutant emissions and concentrations and enhance ambient air quality.

The goal of the current paper was a synthesis of Amino-functionalized Fe₃O₄@SiO₂ core-shell magnetic nanoparticles as a unique efficient photocatalyst for removing organic dyes from aqueous environments. The magnetic Fe₃O₄@SiO₂ core-shell was produced by a silica source to avoid aggregation by the co-precipitation method. Next, functionalized by using 3-Aminopropyltriethoxysilane (APTES) via a post-synthesis link. The chemical structure, magnetic properties, and shape of the manufactured photocatalyst (Fe₃O₄@SiO₂-NH₂) were described by XRD, VSM, FT-IR, FESEM, EDAX, and DLS/Zeta potential analyses. The XRD findings approved the successful synthesis of nanoparticles. The photocatalytic activity of Fe₃O₄@SiO₂-NH₂ nanoparticles was examined for MB degradation and the degradation performance was about 90% in the optimum conditions. Also, the cytotoxicity of Fe₃O₄, Fe₃O₄@SiO₂ core-shell, and Fe₃O₄@SiO₂-NH₂ nanoparticles was examined on CT-26 cells using an MTT assay, the finding has shown that nanoparticles can be used for inhibiting cancer cells.

Graphical abstract

Purpose

The purpose of this study was to investigate the applicability of the adsorption process of a persistent organophosphorus pesticide (malathion) from aqueous solutions by using titanium dioxide- polypropylene nanocomposite (Nano-PP/TiO₂).

Methods

The structure of Nano-PP/TiO₂ was specified by field emission scanning electron microscopes (FE-SEM), fourier-transform infrared spectroscopy (FTIR), brunauer-emmett-teller (BET), and transmission electron microscope (TEM) technologies. Response surface methodology (RSM) was applied to optimize the adsorption of malathion onto Nano-PP/TiO₂ and investigates the effects of various experimental parameters including contact time (5-60 min), adsorbent dose (0.5-4 g/l) and initial malathion concentration (5-20000 mg/l). Extraction and analysis of malathion were performed by dispersive liquid-liquid microextraction (DLLME) coupled with a gas chromatography, coupled with flame ionization detector (GC/FID).

Results

The isotherms obtained for Nano-PP/TiO₂ revealed that it was a mesoporous material with a total pore volume of 2.06 cm³/g, average pore diameters of 2.48 nm and a surface area of 51.52 m²/g. The obtained results showed that the Langmuir type 2 was the best-fitted model for delegating the equilibrium data of isotherm studies with adsorption capacity of 7.43 mg/g, and pseudo-second-order type 1 for kinetic model. The optimized conditions to achieve the maximum removal (96%) were at a malathion concentration of 7.13 mg/L, contact time of 52 min and adsorbent dose of 0.5 g/L.

Conclusion

Due to its efficient and appropriate function in adsorbing malathion from aqueous solutions, it was revealed that Nano-PP/TiO₂ can be used as an effective adsorbent as well as in further studies.

Abstract

The final and most crucial step in obtaining clean water is disinfection. More innovative methods of water disinfection have recently been sought. Water disinfection is a promising application for nanoparticles as disinfectants. As a contribution to the literature, biofilm and metal-containing nanoparticles as antiadhesion inhibitors were used in conjunction with ultrasound in this study. The microbroth dilution test was used to reveal the microbiological antibacterial activities of different concentrations of AgNO3 and CuCl2 containing nanoparticles against the Escherichia coli ATCC 25,922 strain, which is an indicator bacterium in water systems. Antibiofilm activities were then investigated using biofilm attachment and biofilm inhibition tests. The inhibitory effect of nanoparticle ultrasonic waves on biofilm contamination was determined using a novel approach. Human keratinocyte cells (HaCaT cell line) were used in cell culture studies after water disinfection, and their cytotoxic effects were demonstrated using the MTT assay. The findings suggest that the nanoparticles utilized might be a viable choice for water disinfection applications. Furthermore, employing ultrasound at low doses with nanoparticles resulted in greater results. One feasible option is to employ nanoparticles to cleanse water without producing cytotoxicity.

In this work, the amount and physical and chemical characteristics of airborne microplastics (MPs) pollution in dust samples in Sistan, located in the eastern part of Iran, is reported. Sampling stations were selected according to the wind direction and population density. MPs were collected by a static dust sampler and analyzed by optical microscopy and FT-IR spectroscopy. Results showed that the distribution frequency of MPs in residential and non-residential areas was 6 to 11 pieces per 100 g (pcs/100 g) with an average abundance of 9.8 pcs/100 g. Fragmented MPs were approximately consisted 64% of total MPs and their sizes were in the range of 0.9–3.8 mm. Polyethylene (49%), polystyrene (21%) and polyester (18%) were the main MPs presented in the dust samples. It was observed that population density and wind direction were the most important parameters affecting MPs pollution in dust.

Introduction

The amount of fibers in the lungs is considered to reflect the cumulative intensity of past asbestos exposure, and bronchoalveolar lavage (BAL) has been proposed to be a good indicator of the presence and quantity of asbestos particles in the lungs. This study evaluated the asbestos concentration in BAL fluids of asbestos-exposed and unexposed pulmonary patients and the environment of Ahvaz city.

Methods

This prospective study was conducted on 80 patients underwent diagnostic fiberoptic bronchoscopy referred to Imam Khomeini Hospital in Ahvaz, Iran, in 2019. Patients with Lung diseases were divided into three groups based on CT scan results: normal (n = 32), lung cancer (n = 40) and Interstitial lung disease (n = 8). The analysis of asbestos fiber concentration in BAL fluid was carried out by Scanning Electron Microscope (SEM).

Results

The positive asbestos test was detected in 69% of all subjects, including 64% of whom had asbestos-related jobs and 74.5% of those with non-related jobs (p = 0.240). The concentrations of asbestos fiber in the BAL in normal patients, lung cancer and interstitial fibrosis (ILD) were 8.13 ± 5.38, 9.66 ± 7.30 and 6.31 ± 1.98 f/ml, respectively (P = 0.492). There was no significant difference between the asbestos levels and exposure history (P = 0.877). The mean concentration of asbestos in the ambient air during the current year was 2.69 ± 0.57 f/ml (2.26–3.70), and the correlation between asbestos levels in BAL and the air was not significant (r = 0.147; P = 0.243).

Conclusions

The exposure of different occupational and non-occupational groups to this carcinogenic substance indicates the need for environmental and individual control measures to reduce and prevent asbestos exposure.

Abstract