Recently, greenhouse gas (GHG) emissions become the hottest issue in the transportation sector. The air transport sector contributes approximately 2% of global greenhouse gas emissions. Reducing greenhouse gas emissions from aircraft is one of the issues taken seriously by the transportation sector. However, air transportation has implemented several ways to reduce carbon emissions, and one of them is by launching a carbon offset program. This study estimates the willingness among Malaysian airline passengers to pay for a carbon offset program to have a better environmental performance. Using a double-bounded dichotomous choice of contingent valuation method (CVM) estimates how much air passengers would be willing to pay to offset carbon emissions generated by their travel. The results obtained from this study suggest that the additional fee for airline tickets will be RM86.00 can be charged to have a better environmental performance.

In the present study, a geopolymer from dolochar ash was synthesized and used for the removal of heavy metal ions such as Co(II), Ni(II), Cd(II), and Pb(II) from the aqueous solution through the adsorption process. The geopolymer was characterized by a series of analytical techniques. The XRD pattern revealed the loss of dolochar ash crystallinity on geoploymerization. The peak at 982 cm⁻¹ observed in the FTIR spectrum due to Si–O–Si and Si–O–Al bonds confirmed the formation of geopolymer. BET surface area analyses indicated the mesoporous nature of the sample. The adsorption experiments revealed the higher removal efficiency of the geopolymer in comparison with the feed dolochar ash. The effects of different experimental factors such as pH, temperature, reaction time, and initial concentration of metal ions on metal uptake efficiency were evaluated to optimize the removal efficiency. The maximum removal of 98–99% was achieved when the pH, temperature, and initial metal ion concentration were 7.8, 343 K, and 10 ppm, respectively. The adsorption process followed the pseudo-second-order rate equation and validated the Langmuir adsorption model. Thermodynamic parameters such as ΔH, ΔS, and ΔG confirmed that the process to be spontaneous and endothermic. This geopolymer was found to compete efficiently with many adsorbents reported in the literature for water treatment.

This work investigated the impact of a clay mineral on toxic waste. The Ivorian Anti-pollution Center discovered the toxic waste from Probo Koala boat on 21 August 2006. This boat had been used to refine oil named naphtha of cokéfaction by Trafigura firm in the sea. The process of refining consists of caustic sodium carbonate washing and produced toxic waste. These toxic wastes have been unloading in 13 zones of the Abidjan district: Akouédo, Abobo, Abobo Alépé road (Djibi village), civile prison road (MACA), industrial zone of Koumassi, Port-Bouët - Vridi CAP Logistic (Rue Saint-Sylvestre)… This situation caused a socio-political crisis and generated the death of many people. To solve this problem, one first part has been excavated and sent to France to be incinerated. A second part is used to be a biopile for bioremediation. After these two processes, the rest of toxic waste remained in the place where they have been unloaded. The analyses of these toxic wastes show that polycyclic aromatic hydrocarbons (PAHs), oxygenated polycyclic aromatic compounds (O-PACs), volatile aromatic compound (VAC), mercaptan and sulfur molecules, and also heavy metal and organometallic are the principal polluters of these contaminated soils. From a mineralogical viewpoint, the tropical climate soils of Ivory Coast in general and district of Abidjan in particular constituted of about 50% of kaolinite, 30 to 40% of smectite, and 10 to 20% of illite (OSTROM 1993). In this study, we want to show the impact of this local clay on toxic waste.

Several regions of the world have been suffering from problems of water quality degradation caused mainly by the input of nutrients such as nitrogen and phosphorus, resulting from anthropic activities. In excess, these nutrients can be considered micropollutants that could be responsible for the blooms of aquatic plant species, algae, and potentially toxic cyanobacteria, resulting in the interference of water quality in the socio-economic and environmental sector. Biological mitigation measures using specific microorganisms have been applied for the removal of micro pollutants due to their high efficiency of nitrogen and phosphorus. The present study analyzed the efficiency of nitrifying bacteria such as N. europaea and N. winodradskyi and P. denitrificans denitrifying bacteria, individually and as a bacterial pool (formed by N. europaea, N. winodradskyi, and P. denitrificans), in removing NH₃, NO₂⁻, NO₃⁻, N, P, and PO₄³⁻, in pure water samples at times 0 to 1440 min and 0 to 7200 min. N. europaea and N. winodradskyi presented 100% removal efficiency for compounds NH₃ and NO₂⁻ respectively, and bacterial pool removed 100% of compounds NO₂⁻ and P at time 1440 min (24 h). At time 7200 min (120 h), P. denitrificans obtained 100% removal of NO₂⁻ and NO₃⁻. Over time, the bacterial pool obtained 100% removal for all compounds analyzed in the present study. This paper demonstrated the excellent performance of microorganisms in the removal of nitrogen and phosphorus compounds in pure water samples.

China has maintained great economic growth in the past and reached the status of a middle-income country. Meanwhile, the relationships among environmental pollution, environmental regulation, and economic growth have attracted wide attention. In addition, some studies have shown that economic growth is not balanced in the division of income between labor and capital, and this has become one of the most important issues in China. The conflict over the environment and income distribution is supposed to cause social welfare loss; therefore, we want to examine the impact of environmental pollution and environmental governance on labor income share. Our empirical results show that the relationship between environmental pollution and share of labor income is positive at the present stage. However, the relationship is not linear but rather an inverted-U shape in the long run. In addition, we tested the effects of environmental regulation on labor income share and found an inverted-U-shaped relationship. Although growing concern about environmental pollution adds to the pressure on the government, our statistical results suggest that there is no perfect way to resolve environmental problems. Additionally, labor unions are expected to play a different role in income distribution.

The oily wastewater was treated by electrocoagulation with Fe₇₈Si₉B₁₃ amorphous ribbons as anode and graphite plates as cathode under such processing parameters as different pH values and current density, respectively. The degradation effect on the oily wastewater was characterized by chemical demand oxygen (COD), while the ribbons before and after using were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results indicate that under the conditions of pH = 3 and current density being 3.125 A/cm², the optimal COD removal efficiency was obtained to be 73.22%. Compared with the ordinary crystalline iron plate, the COD removal efficiency of resultant wastewater degraded by the amorphous ribbons is more than doubled. Simultaneously, the Fe₇₈Si₉B₁₃ amorphous ribbons exhibit good structural stability even after four cycles of using.

This study aims to assess interrelationships between serum lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) concentrations in pregnant women in their third trimester and umbilical cord blood, while inter-metal correlations were also determined. This study is part of the PIPA project (Childhood and Environmental Pollutant Project), whose pilot study was carried out from October 2017 to August 2018 and will be presented here. Blood samples were obtained from 117 mother-umbilical cord pairs and analyzed concerning metal concentrations. A positive correlation was found between metal concentrations in mother and cord blood (R > 0.7, p < 0.001). The results indicate that mother metal concentrations are able to determine child metal concentrations (p < 0.001). The correlations between maternal blood metal concentrations were positive for all assessed metals except for As and Hg. The strongest correlations in this matrix were observed between Cd and Pb (R = 0.471 p = 0.000), Cd and Hg (R = 0.425 p = 0.000), and Pb and Hg (R = 0.427 p = 0.000). Umbilical cord correlations were lower compared to mother blood correlations. In general, the four analyzed metals displayed significant correlations to serum concentrations in both maternal and cord blood.

Autism spectrum disorders (ASDs) are a group of neurodevelopmental disorders defined by a deficit in social interactions and the presence of restricted and stereotypical behaviors or interests. The etiologies of autism remain mostly unknown. Many genetic and environmental factors have been suspected. Among these environmental factors, exposure to several chemical elements has been previously studied. The purpose of this study was to compare the levels of trace elements in the blood plasma of children with ASD with typically developed children (TDC). The participants in this study consisted of 89 children with ASD (14 girls and 74 boys) and 70 TD children (29 girls and 41 boys). The levels of 33 chemical elements have been analyzed by inductively coupled plasma spectrometry (ICP-MS). We detected significant differences in the levels of eight elements between the two groups, among which there were three rare earth elements (REEs): Eu, Pr, and Sc (p = 0.000, p = 0.023, and p < 0.001 respectively); four heavy metals: Bi, Tl, Ti, and V (p = 0.004, p < 0.001, p = 0.001, and p = 0.001 respectively); and one essential element: Cu (p = 0.043). Children with ASD had higher levels of Er, Pr, Sc, Bi, Tl, Ti, and V, and lower levels of Cu in comparison with the TD group. The children exposed to passive smoking had lower levels of lead (Pb) compared with children without exposure (p = 0.018). Four elements (Cr, Er, Dy, and Pr) were negatively correlated to the severity of ASD. The level of Cu was significantly associated with autistic children’s behavior (p = 0.014). These results suggest that children with ASD might have abnormal plasma levels of certain chemical elements (including Er, Pr, Sc, Bi, Tl, Ti, and V, and Cu), and some of these elements might be associated with certain clinical features.

Raphidiopsis raciborskii is being considered an expanding, invasive species all over the world. It is a potentially toxin producer cyanobacterium and form blooms specially in (sub)tropical lakes, causing concern to public health. Thus, controlling such phenomena are of vital importance. To test the hypothesis that a tropical clone of Daphnia laevis is able to reduce the biomass of R. raciborskii, we performed a mesocosm experiment simulating a bloom of this cyanobacterium in field conditions and exposing it to ecologically relevant densities of daphniids. In addition, we tested the hypothesis that omnivorous fish would be able to exert a top-down effect on Daphnia, decreasing the effectiveness of this control. We used treatments with (10 and 20 Daphnia L⁻¹) or without Daphnia and fish (3 per mesocosm). Daphnia was able to significantly reduce the biomass of R. raciborskii only at the highest density tested. Fish had low effect on Daphnia biomass, but it is suggested that nutrient recycling by fish might have contributed to the higher R. raciborskii biomass in fish treatments. This is the first evidence of Daphnia control over saxitoxin-producing cyanobacteria in a tropical ecosystem.

Carwash wastewater (CWW) is considered as an important source of either water pollution or water consumption. Therefore, its treatment is critical not only from the prevention of environmental contamination but also from the recycling of such high-volume water source. Unfortunately, the effective treatment of CWW is almost unknown, complex, and expensive. To overcome the former challenge, this study aimed to systematically review different technologies for CWW treatment. For this, a comprehensive literature survey was conducted and 48 research articles were found suitable to be included in the investigation. The included studies were of coagulation and adsorption (n = 5), membrane-based technologies (n = 15), and electrochemical (n = 11) and combined (n = 17) systems. This comprehensive review showed that the treatment methods of advanced filtration membrane techniques, electrical and chemical coagulation, and advanced oxidation processes can be effective in the removal of pollutants from carwash wastewater (CWW). The mining of different studies, however, showed that the combined methods are the most promising option in the remediation of such wastewater.