Water and sediment samples were collected from six different stations, located along the Nil River between February and June 2015. Concentrations of cadmium, lead, zinc, and copper were determined. The extent of the sediment pollution was assessed, using the multiple pollution indices, namely contamination factor (CF), pollution load index (PLI), and the geoaccumulation index (Igeo). The results showed that the level of metals in water samples exceeded background concentrations for Cd and Pb, and the average values for those elements were higher than those of Zn and Cu, ranked as the following: Pb (0.58)> Zn (0.38)> Cd (0.32)> Cu (0.061). For sedimentary samples, the results showed that Zn and Pb concentrations were greater than the concentrations of Cu and Cd, exceeding the background values (except for Cu). The concentration of the tested heavy metals decreased to the following order: Zn (96.2)> Pb (61.5)> Cu (38.83)> Cd (2.34). The Igeo values revealed that Cd (2.87) and Pb (1.61) had accumulated significantly in the Nil River. Contamination factor (CF) confirmed that the sedimentary samples were moderate to very high in terms of Cd, Pb, and Zn contamination. The Pollution Load Index (PLI) values were above one (>1), indicating an advanced decline of the sediment quality. Also, the results showed that the stations, located at the middle portion of the river (S3, S4, and S5) have higher levels of metals than the other stations (S1, S2, and S6). The assessment of heavy metals' levels in water and sedimentary samples indicated that river water and the sediments in the study area were strongly impacted by agricultural activities and domestic waste water.

This study examines the relation between CO₂ emissions, income, non-renewable, and renewable energy consumption in Algeria during the period extending from 1980 to 2011. Our work gives particular attention to the validity of environmental Kuznets curve (EKC) hypothesis. The autoregressive distributed lag (ARDL) with break point method outcome demonstrates the positive effect of non-renewable type of energy on CO₂ emissions consumption. On the contrary, the results reveal an insignificant effect of renewable energy on environment improvement. Moreover, the results accept the existence of EKC hypothesis but the highest gross domestic product value in logarithm scale of our data is inferior to the estimated turning point. Consequently, policy-makers in Algeria should expand the ratio of renewable energy and should decrease the quota of non-renewable energy consumption.

Psychotropic substances (PSs) are known to affect air and waters, while scarce attention has been paid to their occurrence in settled dusts although they can reach important concentrations there; moreover, no procedures have been developed for this specific purpose. In this study, a list of PSs (i.e., nicotine, cotinine, caffeine, cocaine, cannabinol, Δ⁹-tetrahydrocannabinol, cannabidiol, amphetamine, heroin, and methadone) were characterized in dusts from Rome and Fiumicino international airport, Italy, and from Ouargla city, Algeria. The analytical procedure, based on ultra-sonic bath extraction, silica column chromatography, and GC-MSD analysis, provided good recovery, uncertainty, sensitivity, and lack of interferences for all substances except amphetamine. In NIST SRM-2585 house dust, nicotine, cotinine, caffeine, cocaine, and cannabinol accounted for ~5.95, 0.87, 4.17, 7.0, and 2.2 μg/g, respectively; on the other hand, methadone, tetrahydrocannabinol, cannabidiol, and heroin (all <0.025 μg/g) were below the detection limit of the method. Two sites at the Fiumicino airport were affected by different loads of PSs (e.g., 0.76 and 2.80 ng/m² of cocaine). In Ouargla, where dust was collected in a primary school and a dwelling, nicotine ranged from ~60 ± 50 to ~86 ± 89 ng/m², cocaine was absent, and cannabinoids (0.35 ± 0.43 ng/m² as total) were found only in the home. In Rome, nicotine, caffeine, cocaine, and cannabinol reached ca. 700, 1470, 0.82, and 2.4 ng/m², respectively, in a smokers’ home, but they were ca. 1300, 25,000, 670, and 1700 ng/m² in a non-smoker home. In conclusion, all dusts revealed the presence of illicit PSs. Further studies are necessary to understand the links between the PS amounts in airborne particulates and in dusts, as well as the PS origin and fate in interiors.

When compared to the European guidelines, PM₁₀ (particulate matter up to 10-μm size) concentrations in Algeria are often exceeding the maximum limits, and in general, no information exists on the compounds bound on its surface. The objective of this study was to measure the dioxin-like activity of polychlorinated dibenzodioxines and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (PCBs) in the PM₁₀ fraction at the Sour El Ghozlane cement plant in Algeria. PM₁₀ samples (n = 23) were taken between 24 March and 15 April 2013, using a medium volume sampler and 47-mm PTFE filters. The 24-h samples were dried to determine the PM₁₀ content and afterward extracted, cleaned up, and analyzed with the dioxin-responsive element–chemical-activated luciferase gene expression (DRE-CALUX) bioassay. Our results showed that the measured bioanalytical equivalents (BEQs) were similar to those in other international industrial sites worldwide. The PCDD/Fs and dioxin-like PCBs (dl-PCBs) were positively correlated (rho = 0.6, p = 0.002), indicating that they have similar sources. Furthermore, samples from March showed higher PCDD/F and dl-PCB BEQs and humidity but lower temperatures compared to samples from April, while there was no difference in the PM₁₀ concentrations between the two months. These results reveal that PM₁₀ alone is not a good proxy and that meteorological conditions are an important factor in assessing dioxin-like pollution in the atmosphere. It seems that, at present, there is no health hazard through direct airborne human exposure to dioxin-like pollutants in PM₁₀ from this site. However, it is important to monitor these POPs for a longer period of time and also to gain more insight in their distribution between the particulate and gas phase in relation to meteorological conditions.