The cement industry generates a substantial amount of gaseous pollutants that cannot be treated efficiently and economically using standard techniques. Microalgae, a promising bioremediation and biodegradation agent used as feedstock for biofuel production, can be used for the biotreatment of cement flue gas. In specific, components of cement flue gas such as carbon dioxide, nitrogen, and sulfur oxides are shown to serve as nutrients for microalgae. Microalgae also have the capacity to sequestrate heavy metals present in cement kiln dust, adding further benefits. This work provides an extensive overview of multiple approaches taken in the inclusion of microalgae biofuel production in the cement sector. In addition, factors influencing the production of microalgal biomass are also described in such an integrated plant. In addition, process limitations such as the adverse impact of flue gas on medium pH, exhaust gas toxicity, and efficient delivery of carbon dioxide to media are also discussed. Finally, the article concludes by proposing the future potential for incorporating the microalgae biofuel plant into the cement sector.

Oily organic waste is a promising feedstock for anaerobic co-digestion. Free long-chain fatty acids (LCFAs) produced from lipids can inhibit methanogenic consortia, so optimal control of LCFA concentration is the key to successful operation of co-digestion. Most LCFAs are present in the solid phase, making them difficult to be detected and monitored. This study proposes a simple and easy method for detecting LCFAs in both the liquid and solid phases of anaerobic digestate by combining liquid–liquid extraction followed by solid-phase extraction (SPE) and spectrophotometric analysis. The extraction procedure successfully removed impurities that interfere with the absorbance spectrum and ensured high recovery rates of LCFAs. The utility of the pretreatment used for the extraction was discussed using thermodynamic analysis and calculations of phase equilibrium for the solvent extraction system. The absorbance spectrum shift of pyridinium N-phenolate betaine (PNPB) dye-stained solution showed a good correlation with LCFA concentration and enabled highly sensitive measurements. Good quantification was demonstrated in experiments using various digestate samples obtained from the laboratory, pilot, and full-scale reactors.

The purpose of this study was to monitor and model indicators of soil contamination, organic matter evolution and biochemical processes involved in a long-term phytoremediation process. Populus nigra L., Paulownia tomentosa Steud., Cytisus scoparius L. and natural vegetation were used in differently contaminated areas (high, medium and low levels of contamination). Parameters indicating contamination (total petroleum hydrocarbons (TPH) and heavy metals) and agronomic (C, N and P) and functional (enzyme activities) soil recovery were monitored for 3.5 years. Three subareas with different levels of contamination (high, medium and low) were identified according to the Nemerow Index. A considerable decrease in TPH (52% on average) over time in the whole site was measured, while the metal reduction was only of about 22% at surface level. A stimulation in metabolic soil processes and improvement in the chemical quality of the soil was also observed throughout the experimental site. Statistical analysis modelling showed that the contaminant content decreased following a one-phase decay model, while the dramatic increase in enzyme activities could be represented by an exponential growth equation. On the basis of our data, it is possible to conclude that the initial contamination level affected neither the decontamination process nor the improvement in soil quality, which occurred similarly in the three different contaminated areas.

The present study was conducted to examine the protective effect of olive leaf extract (OLE) against glycerol-induced oxidative stress in rats. Sixty male albino rats were used and allocated randomly into four groups, each of 15 rats. Groups (1) and (2) were administered intraperitoneally (i.p.) a single dose of 500 μL normal saline and hypertonic glycerol solution (10 mL/kg b.wt., 50% v/v, in sterile saline), respectively, followed by a 24-h period of water deprivation. Group (3) was orally given OLE (500 mg/kg b.wt.) for 22 days and glycerol as mentioned above on the 14th day of OLE administration followed by a 24-h period of water deprivation. Group (4) was administered OLE alone. Five rats from each group were sacrificed and samples were collected 1, 5, and 8 days after water deprivation. Alterations in hematobiochemical parameters, renal and hepatic oxidative stress markers, as well as histopathology of the kidney and liver, were evaluated. Glycerol treatment resulted in significant hematological and biochemical alterations as well as significant renal and hepatic oxidative stress. Administration of OLE has significantly ameliorated renal dysfunction, morphological alterations of kidney and liver, and relieved the oxidative stress. These findings show obviously the role of oxidative stress and its relevance to renal dysfunction and suggest the ameliorative impact of OLE in glycerol-induced acute kidney damage in rats, possibly due to its antioxidant properties.

To reveal the characteristics of tetracycline (TC) photocatalytic degradation under Cu(II) coexistence, effects of Cu(II) on TC photocatalytic degradation by ZnO nanoparticles (ZnO NPs) as a function of pH, humic acid (HA), and initial Cu(II) concentration were investigated. Interaction of TC with Cu(II) in the treatment process was analyzed by circular dichroism (CD) spectroscopy, while TC degradation pathway was investigated by high-performance liquid chromatography-mass spectrometry. Sixty-five percent and ninety-one percent TC degradation within 60 min in the absence and presence of Cu(II), respectively, was reported. Both adsorption and photocatalytic degradation of TC under Cu(II) coexistence increased with increasing pH from 3 to 6, while decreased with further increase in pH. HA inhibited the degradation of TC by ZnO NPs both in the presence as well absence of Cu(II), while TC degradation decreased from 91 to 73% and from 73 to 37% in the presence and absence of Cu(II), respectively. TC degradation by ZnO NPs first increased then decreased with increasing Cu(II). Maximum TC degradation (about 94%) was obtained in the optimum concentration range of Cu(II) (0.05–0.15 mmol/L). In addition, there was a lag effect between TC adsorption and degradation on ZnO NPs. TC degradation was improved via Cu(II)–TC surface complexation and followed N-demethylation and hydroxylation routes. This study could be of potential importance in extrapolating the transformation of TC or other antibiotics under the coexistence of heavy metals in water.

Chlordecone is an organochlorine pesticide that was extensively used to control the banana root borer population in the French West Indies until 1993. Its persistence in soil has led to widespread pollution of the environment, and human beings, including pregnant women, are still exposed to this chemical. High levels of exposure to chlordecone during gestation have been shown to cause congenital anomalies, including undescended testes in rodents. We assessed the associations between chlordecone concentrations in maternal and cord plasma and the risk of congenital anomalies in the Timoun Mother-Child Cohort Study (2004–2007) that included 1068 pregnant women in Guadeloupe. Odds ratios were estimated using unconditional logistic regression analysis, controlling for confounding factors. The median plasma concentrations in maternal and cord plasma were 0.39 μg/L and 0.20 μg/L, respectively. Thirty-six children were diagnosed with malformations according to the European Registration of Congenital Anomalies guidelines and 25 with undescended testes. There was no association between maternal or cord plasma concentration of chlordecone and the risk of overall malformations nor undescended testes. These results suggest that prenatal exposure to the currently observed environmental levels of chlordecone in French West Indies does not increase the risk of birth defects.

Cyanide is highly toxic and must be destroyed or removed before discharge into the environment. This study examined the ability of commercial anion-exchange resins to remove residual cyanide complexes from industrial plating wastewater as a complement to conventional treatment. Cyanide removal experiments were conducted with various initial concentrations, reaction times, and temperatures, and the presence of co-existing anions. The maximum cyanide removal capacity (Qₘ) of the Bonlite BAMB140 resin is 31.82 mg/g and effectively removes cyanide from aqueous solution within 30 min. The cyanide removal by the resin is an endothermic process and is affected by the presence of anions in industrial plating wastewater. The relative competitiveness observed in this study was sulfate > nitrate > chloride. A mixture of 0.05 M NaCl and NaOH regenerates resin for continuous reuse for 5 cycles. The Bonlite BAMB140 resin was able to remove residual cyanide complexes from industrial plating wastewater, but the removal capacity of the resin was reduced by more than three times in batch (9.94 mg/g) and column (6349.12 mg/L) systems. Based on the results, the anion-exchange resins are expected to be used as a complementary technique to remove residual cyanide complexes in industrial plating wastewater after conventional treatment.

Valle del Mayo is an important agricultural area at the northwest of Mexico where up to 20,000 L of a mix composed of glyphosate and tordon is used in drains and canals. This study was carried out in order to evaluate the cellular damage caused by glyphosate, aminomethylphosphonic acid (AMPA), and picloram in agricultural workers. Biomonitoring was performed through the quantification of herbicides in urine using HPLC (high-performance liquid chromatography) to then evaluate the cellular damage in exposed people by means of an evaluation of micronuclei and cellular proliferation in lymphocyte cultures. The urine samples (n = 30) have shown a concentration of up to 10.25 μg/L of picloram and 2.23 μg/L of AMPA; no positive samples for glyphosate were reported. The calculation of the external dose reveals that agricultural workers ingest up to 146 mg/kg/day; however, this concentration does not surpass the limits that are allowed internationally. As for the results for the micronuclei test, 53% of the workers showed cellular damage, and the nuclear division index test reported that there was a significant difference (P < 0.05) between the exposed and the control population, which indicated that the exposure time to pesticides in the people of Valle del Mayo can induce alterations which can cause chronic damage.

Honeybees forage a large spatial area around the hives. In addition, honey production takes place in various environments, and polluted environment is often hard to detect. It impacts both human and beehive health, especially through honey which is used for human consumption. Pollen analysis was conducted by a novel approach through a multivariate principal component analysis where it was possible to obtain grouping patterns related to foraging plant species. Samples of honey were acquired from three different environmental production systems: (i) honey from the apiaries in the vicinity of thermal power plant, (ii) apiary of certified organic production and (iii) the conventional production with semi-controlled production. Significantly higher contents of the Pb, Cd and Zn are found in the analysed honeys taken near the thermal power plant compared with those of the other analysed honeys. The origin of Zn, Pb and Cd in the honey is the contaminated forage plants and foraging honeybees. Honey from certified organic production differentiated significantly from other two types of production by the water content, electrical conductivity and total soluble solids and notably it contained significantly less ash and lead. There is a clear advantage of certified organic honey in terms of heavy metal residues as the most prominent pollution factor in honey. Therefore, honey can be used as the broad range environmental pollution indicator, as bees will forage on polluted plants and bring the pollutant from a wide spatial range inside the hive, where it can be traced in the honey. Graphical abstract

To forecast possible future environmental risks, numerous models are developed to predict the hourly values or daily averages of air pollutant concentrations using streaming data (a kind of big data collected from the Internet). On the one hand, real-time hourly data is massive and redundant, making it difficult to process. On the other hand, daily averages cannot reflect the fluctuations of air pollutant concentrations throughout the day. Therefore, a double decomposition and optimal combination ensemble learning approach is proposed for interval-valued AQI (air quality index) forecasting in this paper. In the first decomposition, considering the strong seasonal representation of AQI, the original data of each year is decomposed into four seasonal subseries on the basis of the Chinese calendar. Subsequently, we reconstruct the data of the same season in different years to get a new seasonal series to reduce the interference of seasonal changes on AQI forecasting. In the second decomposition, due to the nonlinearity and irregularity of interval-valued AQI time series, BEMD (bivariate empirical mode decomposition) is employed to decompose the interval-valued signals into a finite number of complex-valued IMF (intrinsic mode function) components and one complex-valued residue component with different frequencies to reduce the complexity of interval times series. Interval multilayer perceptron (iMLP) is utilized to model the lower bound and the upper bound simultaneously of the total components to obtain the corresponding forecasting results, which are merged to produce the final interval-valued output by an optimal combination ensemble method. Empirical study results show that the proposed model with different datasets and different forecasting horizons is significantly better than other considered models for its superior forecasting performances.