The study objective was to assess tobacco smoking prevalence in Kuwaiti adults in relation to sociodemographic characteristics. A cross-sectional study survey was conducted in 2014 on 3917 Kuwaiti citizens (18–69 years) following the World Health Organization (WHO) STEPwise Approach to Surveillance (STEPS) methodology. The study assessed prevalence of self-reported ever-smoking or currently smoking tobacco products and exposure to secondhand smoke in relation to demographic and smoking-related characteristics. The prevalence of “ever smoker” in men and women was 49.9% and 4.4%, respectively, whereas the prevalence of “current smoker” was 39.2% and 3.3%, respectively. Sex (adjusted OR [AOR], 19.2 [95% confidence interval (CI) 13.0–28.3], male versus female) was significantly associated with current smoking. Among daily smokers, 87.1% used manufactured cigarettes. The average daily number of manufactured cigarettes for men and women was 21.8 and 13.0, respectively. Mean age at smoking initiation was 17.5 years (95% CI 17.2–17.9). The prevalence of secondhand smoke at home and work was 38.6% and 29.9%, respectively. Half of Kuwaiti men have smoked at some point in their life with most of these being current smokers. Secondhand smoke is a common exposure at home and work, posing serious health risks to the population.

Phosphorus (P) is highly related to water quality during shrimp culture. Recognizing P transformation in pond-based cultures is crucial for sustainable and healthy aquaculture. However, P transformation remains unclear in the sediment of Penaeus vannamei cultures, although commercial species have been pervasive worldwide. To determine P transformation, samples with different culture years were collected from Zhejiang province, China. Sequential chemical extraction was applied to reveal the composition of inorganic P, while phosphatase activity was used to evaluate the biomineralization of organic P. The results indicated that the consecutive culture of Penaeus vannamei promoted the dissolution potential of sedimentary P. This was attributed to anoxic iron reduction that increased the formation of loosely bound P and Fe (II)-P. However, this phenomenon was dominated by biomineralization, which transformed the organic P to inorganic P. The results suggested that consecutive culture changed the microbial community structure in the sediment as well as the gene functions. The Shannon Wiener index showed that increasing the culture duration significantly decreased the stability of the microbial community. Overall, this study suggests that long-term consecutive culture of Penaeus vannamei may increase the P release potential of the sediment, which increases the risk of pond eutrophication.

Photocatalysis is one of the most important process and was used to eliminate various organic pollutants as phenol in water. In this research study, a new composite containing Kaolinite, cement, and wood fibers modified by titanium oxide TiO₂ was elaborated in order to be used in addition of building materials, as photocatalyst for the degradation of phenol. Different kinds and amounts of TiO₂ (PC500, P90, and C-TiO₂) were immobilized by a simple method inside the composite materials based. The matrix of the hybrid materials was characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), N₂ adsorption-desorption (BET), and scanning electron microscope (SEM). These investigations confirmed the dispersion of titania in the new composite materials. The FTIR result has shown that clay particles were successfully treated before their insertion in the composite, by the appearance of two peaks at 2921–2851 cm⁻¹. The XRD results reveal the identification of crystalline phase of TiO₂ as anatase. The photocatalytic activity of the composite materials was investigated towards degradation of phenol in aqueous solution under UV light irradiation (369 nm). It has been found that photocatalytic efficiency was significantly enhanced when TiO₂ is added. The highest photocatalytic activity has been shown by 3% P90-comp of 41.65% in comparison with 3% PC500 and 3% C-TiO₂ which are 29.88% and 22.64 %, respectively. It was shown that the experimental data of kinetic reaction are well fitted by first-order model.

This study aims at examining the use of an advanced meso-scale continuous-flow photochemical reactor for the photocatalytic conversion of CO₂ with water into fuel over TiO₂ (P25), Ag/TiO₂, and Ag/TiO₂/RGO catalysts. The silver loaded photocatalysts were prepared by one-step process via hydrothermal method. The prepared photocatalysts were characterized by various characterization techniques in order to identify the morphological, chemical, physical, and optical properties. The photocatalytic activity of the as-prepared catalysts was firstly examined by the photoelectrochemical (PEC) measurements and secondly by the photocatalytic reduction of CO₂ in the proposed setup. Liquid products were analyzed using gas chromatography-mass spectrometry (GC-MS) and total organic carbon (TOC) techniques. It was found that the ternary composite revealed an outstanding performance towards CO₂ photocatalytic reduction, where its selectivity was directed towards methanol production. The incorporation of graphene nanosheets enhanced the photocatalytic reduction of CO₂ by 3.3 and 9.4 times compared with Ag/TiO₂ and bare TiO₂, respectively, using the proposed photochemical reactor in a continuous mode. This study sheds the light on a novel type of a photocatalytic reactor where CO₂ conversion over Ag/TiO₂/RGO ternary composite was evaluated. A meso-scale continuous-flow photochemical reactor

Fluorapatite (FAp) is the largest phosphorous (P) reservoir on Earth. However, due to its low solubility, dissolved P is severely deficient in the pedosphere. Fungi play a significant role in P dissolution via excretion of organic acids, and in this regard, it is important to understand their impact on P cycling. The object of this study was to elucidate the balance between P release and F toxicity during FAp dissolution. The bioweathering of FAp was assisted by a typical phosphate-solubilizing fungus, Aspergillus niger. The release of elements and microbial activities were monitored during 5-day incubation. We found that the release of fluorine (F) was activated after day 1 (~90 mg/L), which significantly lowered the phosphate-solubilizing process by day 2. Despite P release from FAp being enhanced over the following 3 days, decreases in both the amount of biomass (52% decline) and the respiration rate (81% decline) suggest the strong inhibitory effect of F on the fungus. We thus concluded that F toxicity outweighs P supply, which in turn inhibits fungi growth and prevents further dissolution of FAp. This mechanism might reflect an underappreciated cause for P deficiency in soils.

The settlement of non-spherical particles, such as propagules of plants and natural sediments, is commonly observed in riverine ecosystems. The settling process is influenced by both particle properties (size, density, and shape) and fluid properties (density and viscosity). Therefore, the drag law of non-spherical particles is a function of both particle Reynolds number and particle shape. Herein, a total of 828 settling data are collected from the literatures, which cover a wide range of particle Reynolds number (0.008–10000). To characterize the influence of particle shapes, sphericity is adopted as the general shape factor, which varies from 0.421 to 1.0. By comparing the measured drag with the standard drag curve of spheres, we modify the spherical drag law with three shape-dependent functions to develop a new drag law for non-spherical particles. Combined with an iterative procedure, a new model is thus obtained to predict the settling velocity of non-spherical particles of various shapes and materials. Further applications in hydrochorous propagule dispersal and sediment transport are projected based on deeper understanding of the settling process.

Pharmaceuticals pose a major threat to the marine environment, and several studies have recently described their negative effects on marine organisms. Pharmaceutical compounds are constantly being released into aquatic ecosystems, and chronic exposure, even at low concentrations, may have a major impact on marine organisms. The purpose of the present study is to evaluate the biological changes induced by one of the most widely used pharmaceuticals—paracetamol—in the blue mussel Mytilus edulis, after a long-term exposure at environmentally relevant concentrations. We present our data alongside and in comparison with results from a previous short-term exposure, to demonstrate the significance of exposure period on the effects of paracetamol in adult blue mussels. After 24 days of laboratory exposure, seven potential target genes were selected to examine toxicological effects in mussels’ gonads and possible disruptive effects on reproductive processes. The results show the modulation of some important reproduction-related genes: estrogen receptor-2 (ER2), vitelline envelope zona pellucida domain-9 (V9), and vitellogenin (VTG). Variations in mRNA expression of four other genes involved in apoptosis (HSP70, CASP8, BCL2, and FAS) are also highlighted. Histopathological alterations caused by paracetamol, together with neutral red retention time response in mussels’ hemocytes, are presented herein. Overall, this study highlights the exacerbated effects of low concentration of paracetamol after chronic exposure, similar to the damage induced by higher concentrations in a short exposure scenario, thus emphasizing the importance of length of exposure period when studying the effects of this substance. Additionally, this study also discusses the potential of paracetamol to inflict several major changes in the reproductive system of mussels and thus possibly affect the survival of populations.

Stabilized/solidified hazardous wastes may lose their structural integrity and stability when exposed to long-term extreme weather conditions, such as repeated wetting–drying and freezing–thawing (F–T). This situation causes wastes to become environmentally risky again even if they are stabilized and solidified. In this study, the effects of F–T cycles on the strength and pollutant leachability of stabilization/solidification (S/S) products of zinc extraction residue (ZER) stabilized/solidified by Portland cement (PC), fly ash (FA), and alkaline phosphate (AP) were comprehensively investigated. S/S efficiency and F–T resistance of the samples were determined by unconfined compressive strength (UCS), and leaching tests widely applied in the USA (TCLP), European Union (EN-12457/1-4 2020), and Turkey (TS-EN 12457/4). In addition, X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses and visual inspection were performed to examine the variations in mineralogical and morphological structures. S/S efficiency and F–T resistance changed depending on the type and amount of S/S reagent used and decreased in the order of PC+AP>PC>>FA. All applied S/S procedures, except for 10% PC addition, were found to be suitable for the S/S of ZER from the viewpoint of the achievement of the minimum required strength and pollutant leachability. F–T events did not change the mineralogical structures of the S/S products, but significantly reduced the UCS value by causing structural deformation. The pollutant concentrations released from the samples that lost their monolithic structure by crumbling after certain cycle increased with the increasing F–T cycle, causing a change in the storage criteria of the samples. Therefore, it is important to consider and apply the F–T cycle as a standard test in addition to the existing leaching and strength tests for S/S products of the wastes in terms of minimizing environmental risks.

Potentially toxic elements (PTEs) are of great concern in steel mill wastes. Therefore, in order to use them as potential fertilizers in soil, risk assessments are needed. Three steel mill wastes were tested as possible amendments for soils at seven different doses (0, 0.5, 1, 2, 4, 8, 16 t ha⁻¹): phosphate mud (PM), metallurgical press residue (MPR), and filter press mud (FPM) during rice cultivation in a pot experiment in a Haplic Gleisol. Analysis on rice tissues, including roots, shoots, husk, and grains, were conducted and contents of Cu, Cd, Ni, Zn, Mn, and Pb were assessed. Translocation and bioaccumulation factors were calculated for each element. In general, PTEs are more accumulated in roots and greater contents of Zn and Mn were found, while the lowest ones were found for Pb, probably due to its lack of functional roles during plants development. Higher translocation was observed for Mn, which is associated to the redox conditions of rice cultivation and the high mobility of this element under this condition. Application of steel mill wastes can increase PTE bioavailability and translocation factors, especially PM, but all of the wastes reveal a high hazard index.

Cyanotoxins released by cyanobacteria are currently a concern due to potential impacts on plants, animals, and human health. Many instances of cyanotoxin poisoning have been reported around the world, including acute, chronic, and fatal cases. In recent years, the Tri An Reservoir (TAR) in Vietnam has experienced influxes of cyanotoxins from toxic blue-green algae at levels which exceed the World Health Organization’s (WHO) permitted level of 1 μg/L. Previous studies have focused on assessing cyanobacterial diversity, the presence of cyanotoxins in water, or the effect on aquatic plants and animals. Therefore, this study aims to assess the health risks associated with cyanobacteria exposure for people living near the TAR in Dong Nai Province, Vietnam, using the Monte Carlo simulation technique. In total, 120 water samples were collected at five points of the reservoir from 2017 to 2019. Seventy-five local people who have been exposed to the water from the reservoir were interviewed. Microcystin (MC) concentration was measured with a high-pressure liquid chromatography (HPLC) system and was used to assess the health risk to local people. The results showed that the MC concentration in raw water ranged from below detection limit (BDL) to 18.67 μg/L in 2017 and from BDL to 8.6 μg/L in 2019, with the predominant variant being MC-RR. The concentration of MCs in the TAR in 2017 and 2019 exceeded the WHO’s permitted level of 1 μg/L by 76% and 19%, respectively. The results showed that the rate of MC exposure likely to cause cancer was approximately 1–5%. The oral exposure rate while bathing was less than 2.5%. Direct oral exposure of cyanobacteria with no carcinogenicity was relatively high (40–50%) and the most affected group was adults.