Atmospheric concentrations of PCDD/Fs, dl-PCBs and some pesticides in northern Algeria using passive air sampling.

Two monitoring campaigns were conducted in northern Algeria to assess the contamination level of pesticides and persistent organic pollutants (POPs) in ambient air. Six pesticides (α- and γ-hexachlorocyclohexane, fenitrothion, malathion, chlorpyrifos and λ-cyhalothrin) were monitored at two different sampling locations during the first campaign. The passive sampling was performed at a semi urban/industrial site but also in a rural area between July to September 2008. The pesticides levels, analyzed by GC/MS/MS, ranged from 16 pg m(-3) to 11 ng m(-3). The second campaign was carried out from May to November 2009. The polychlorodibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) concentrations were evaluated at an urban/industrial and at an industrial site. The PCDD/Fs and dl-PCBs, analyzed by HRGC/HRMS, ranged from 249 to 923 fg TEQ m(-3). In addition to passive sampling, active sampling using an isokinetic sampler was also performed at an industrial waste incinerator. The PCDD/Fs and dl-PCBs found was 268 pg TEQ m(-3). This paper presents the first measurements of PCDD/Fs, dl-PCBs and pesticides in rural, urban and industrial areas of northern Algeria.

Relative characterization of rosemary samples according to their geographical origins using microwave-accelerated distillation, solid-phase microextraction and Kohonen self-organizing maps.

For centuries, rosemary (Rosmarinus officinalis L.) has been used to prepare essential oils which, even now, are highly valued due to their various biological activities. Nevertheless, it has been noted that these activities often depend on the origin of the rosemary plant and the method of extraction. Since both of these quality parameters can greatly influence the chemical composition of rosemary oil, an original analytical method was developed where "dry distillation" was coupled to headspace solid-phase microextraction (HS-SPME) and then a data mining technique using the Kohonen self-organizing map algorithm was applied to the data obtained. This original approach uses the newly described microwave-accelerated distillation technique (MAD) and HS-SPME; neither of these techniques require external solvent and so this approach provides a novel "green" chemistry sampling method in the field of biological matrix analysis. The large data set obtained was then treated with a rarely used chemometric technique based on nonclassical statistics. Applied to 32 rosemary samples collected at the same time from 12 different sites in the north of Algeria, this method highlighted a strong correlation between the volatile chemical compositions of the samples and their origins, and it therefore allowed the samples to be grouped according to geographical distribution. Moreover, the method allowed us to identify the constituents that exerted the most influence during classification.

Chemical characteristics of organic aerosol in Bab-Ezzouar (Algiers). Contribution of bituminous product manufacture.

The organic compositions of atmospheric particulate matter from Bab-Ezzouar (Algiers) have been investigated to assess the air pollution levels suspected to be caused by asphalt product and yeast manufactures. After a medium-volume air sampling, soxhlet extraction, alumina elution and HPLC separation, the extracts were analysed by high-resolution gas chromatography (HRGC) and gas chromatography coupled to mass spectrometry (GC-MS). The composition of n-alkane and polycyclic aromatic hydrocarbons (PAH) fractions reflected the petrogenic origin from the emission of asphalt materials production in addition to vascular plant wax emissions. In contrast, microbial activities seemed to play the main role for the presence of n-alkanoic acids at Bab-Ezzouar. The sole nitrated polycyclic aromatic hydrocarbons (NPAH) observed, i.e., 2-nitrofluoranthene (2NFA), was very likely to arise from gas-phase photochemical reaction of parent PAH in the atmosphere. The total aerial levels ranged from 75 to 206 ng m(-3) for n-alkanes, from 153 to 345 ng m(-3) for n-alkanoic acids and from 44 to 100 ng m(-3) for PAH and NPAH. Although the samples were collected during the hot season, the levels of these pollutants seemed to be important and of environmental concern, especially for PAH species.

Organic aerosols in urban and waste landfill of Algiers metropolitan area: occurrence and sources.

In both downtown Algiers and the waste landfill of Oued Smar, the concentrations of particulate organic compounds comprising n-alkanes, n-alkanoic acids, n-alkan-2-ones, polycyclic aromatic hydrocarbons (PAHs), oxygenated (OPAHs), and nitrated polycyclic aromatic hydrocarbons (NPAHs) in ambient air were measured from May 1998 to February 1999. All the components except OPAHs had a tendency to strongly increase in colder weather. Motor vehicles were found to be the main source of airborne particles in downtown Algiers, while the combustion and pyrolysis processes and bacterial activity seemed to concur to the air pollution at the Oued Smar waste landfill. The biogenic emission, which was restricted to the lighter fraction of the n-alkanes and n-alkanoic acids, appeared to contribute at a lesser extent. The in-situ generation of some OPAHs and NPAHs seemed to contribute to air pollution, especially during the summertime. As expected, the ambient concentrations of NPAHs and OPAHs were lower than those of their parent PAHs. The seasonal variations in ambient NPAH and OPAH concentrations are due partly to fluctuations of precursors including NOx, 03, and OH radicals. In general, the wintertime concentrations of the organic pollutants in Algiers were similar to those measured in Europe and especially over the Mediterranean Basin. Further investigations have been planned in order to obtain a thorough knowledge of the air pollution as well as the organic content of materials burning atthe Oued Smarwaste landfill. In particular, our concern will be addressed to sources of toxic components, to formulate strategies suitable for reducing health risk for the populations living in the region of Algiers.

Organic content of particulate matter in the atmosphere of Ouargla City, Algeria.

The particle-bound organic compounds comprising n-alkanes, n-alkanoic monocarboxylic acids, polynuclear aromatic hydrocarbons (PAH) and nitrated polynuclear aromatic hydrocarbons (NPAH) were investigated in ambient air of the Ouargla city area (Algeria) during a short campaign performed in November 1999. The distribution profile of n-alkanes was consistent with the petrogenic origin of aerosols, suggesting that they were related to torching processes of crude oil refuses in the petroleum extraction field located not far from Ouargla. Instead, the presence of n-alkanoic acids of low molecular weight was indicative of microbial activity experienced by the site. PAH levels were low when compared to other polluted areas. The presence of 2-nitrofluoranthene and 2-nitropyrene, which can result from in-situ nitration of fluoranthene and pyrene, was concurrent with the substantial depletion of the most reactive among PAH, suggesting that photochemical processes influence the composition of the Saharian atmosphere.