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PubMedDate not supplied

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.

Air Pollutants↗
PubMed2002

Effect of copper binding by suspended particulate matter on toxicity.

The kinetics of Cu(II) interactions with Susquehanna River (mid-Atlantic, USA) particle suspensions using the copper ion selective electrode (Cu-ISE) method indicated that the concentration of Cu2+ in both the suspension and filtrate was kinetically controlled; the reaction of Cu(II) in the suspension was faster than that in the filtrate. Bioassay tests were performed in continuous flow-through bioassay systems to examine the effect of kinetics of Cu(II) interactions with suspended solids on the toxicity of Cu to Ceriodaphnia dubia. The toxicity curves were displaced to higher total Cu concentration as the reaction time increased, indicating that such interaction of Cu with solids was time dependent. Further, the toxicity curves overlapped for reaction times of 6 and 24 h, indicating that the reaction was relatively rapid and that equilibrium was achieved within 6 h. The survival of organisms was related to the free Cu2+ concentration but deviated from the result for bioassays in which dissolved organic matter (DOM) rather than particles reacted with the added Cu(II) to affect the free Cu2+ concentration. It may be interpreted that, besides the toxic effect of Cu2+, particles exert adverse influences on the organisms.

Animals↗
PubMed2003

[Airborne particulate matter: definitions, health effects, measurement and summary of environmental studies in Rome].

Epidemiological studies conducted in different countries have reported associations between increases in PM concentration and increases in morbidity and mortality, particularly among those people with respiratory or cardiovascular diseases. However, there are still important unanswered questions concerning potential biologic mechanisms of PM effects, the identification of the factors responsible of the adverse health effects (size and or chemical composition), the groups of people that may be particularly sensitive to the effects of PM. The most recent hypotheses indicate that ultrafine particles (UF) (< 0.1 microm) and transition metals (like Fe) may play an important role in the induction of toxic effects. Results obtained during last years in some sites located in the city center of Rome, showed mean annual levels of PM10 and PM2.5, that were often higher than 40 microg/m3, with peak values during winter months. UF particles concentrations showed similar seasonal trends, and daily trend correlated with increasing traffic fluxes, with peak levels of 10(5) p/cm3.

Aerosols↗
PubMed2004

Mutagenicity of airborne particulate matter PM10.

Mutagenic activity of extractable organic matter (EOM), from airborne particles collected over winters in four towns of Czech Republic, was investigated by the means of Salmonella typhimurium indicator strains TA98 and YG1041 using the Ames plate incorporation assay. Mutagenicity of all tested samples showed significant dose-related increase in number of revertants per mg of EOM. The direct mutagenic potency detected with TA98 increased further in the presence of external metabolic activation. The mutagenic potency detected with YG1041 was about two orders of magnitude higher than that detected with TA98. The mutagenicity results correlated with the concentrations of the polycyclic aromatic hydrocarbons (PAHs) determined by GC/MS. Local differences in mutagenicity, expressed as numbers of revertants per m3 of air, were observed with the highest values in Prague air samples. For routine ambient air mutagenicity monitoring, the use of YG1041 and the plate incorporation test are recommendable.

Air Pollutants↗
PubMed2004

Sources of fine particulate matter in personal exposures and residential indoor, residential outdoor and workplace microenvironments in the Helsinki phase of the EXPOLIS study.

OBJECTIVES: This study assessed the source contributions to the mass concentrations of fine particles (PM2.5) in personal exposures and in residential indoor, residential outdoor, and workplace indoor microenvironments of the nonsmoking adult population unexposed to environmental tobacco smoke in Helsinki, Finland. METHODS: The elemental composition of 48-hour personal exposure and residential indoor, residential outdoor, and workplace indoor PM2.5 was analyzed by energy-dispersive X-ray fluorescence spectrometry for 76 participants not exposed to environmental tobacco smoke and 102 participating residences with no smoking in Helsinki as a part of the EXPOLIS study. Subsequently, a principal component analysis was used to identify the emission sources of PM2.5-bound elements and black smoke in each microenvironment, and this information was used to identify the corresponding sources in personal exposures. Finally, source reconstruction was done to determine the relative contributions of each source type to the total PM2.5 mass concentrations. RESULTS: Inorganic secondary particles, primary combustion, and soil were the dominant source types for the PM2.5 mass concentration in all the microenvironments and personal exposures. The ratio of the residential indoor-to-outdoor PM2.5 concentration was close to unity, but the corresponding elemental ratios and source contributions varied. Resuspension of soil dust tracked indoors was a much larger contributor to residential and workplace indoor PM2.5 than soil dust to residential outdoor PM2.5. Source contributions to personal PM2.5 exposures were best approximated by data from residential and workplace indoor microenvironments. CONCLUSIONS: Population exposure assessment of PM2.5, based on outdoor fixed-site monitoring, overestimates exposures to outdoor sources like traffic and long-range transport and does not account for the contribution of significant indoor sources.

Adult↗
PubMed2004

The Elbe flood in August 2002--occurrence of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/F) and dioxin-like PCB in suspended particulate matter (SPM), sediment and fish.

As a result of extreme precipitation in August 2002 major flooding occurred in the catchment area of the rivers Elbe, Vltava (Moldau) and Mulde. Pollutants from industrial sites and from municipal sewage treatment works (STW) entered the Elbe and led to a serious pollution problem in the river. PCDD/F concentrations (in pg WHO-TEQ/g dw) in SPM ranged from 7-150, in sediments from 3-140; the "safe sediment value" of 20 was exceeded in 46% of the samples. 24 eels showed a wide concentration variation for these contaminants. The WHO-PCDD/F+PCB-TEQ values lay in the range from 11-56 pg/g ww, whereby the WHO-PCB-TEQ values were several times higher than the WHO-PCDD/F-TEQ values. The maximum permitted value of 4 pg WHO-PCDD/F/g ww (EU Directive No. 2375/2001) was reached or exceeded in 54% of the individuals. A statistical analysis using data from SPM and sediment samples showed that in the Czech river section the flooding activated a contamination source in the vicinity of the Spolana works. The influence of the tributary Mulde could be clearly demonstrated. Only a major clean-up of the contaminated sites in Bitterfeld can lead to a mid to long term improvement in respect of PCDD/F and dioxin-like PCB input into the Elbe.

Animals↗
PubMed2004

[Determination of politary organic compounds in atmospheric fine particulate matter in Beijing City].

A determination method was developed for the quantification of polar organic compounds in atmospheric fine particles in Beijing City by GC-MS. The optimally reactive conditions of two derivative methods were set up. The related coefficients (R2) of standard curves were 0.995-1.000. The precise of the GC-MS was 1%-10%, and the quantified detection limits ranged from 0.1 to 4.0 ng x microL(-1) depending on the various standard compounds. The percent relative standard deviation of standards and atmospheric samples were 3%-20% and 3%-17%, respectively. The methods were applied for Beijing fine particle samples in summer, fall, and winter in 2002. Total 42 polar organic compounds were identified and quantified, including 30 n-aliphatic and n-alkenoic acid species, 5 aliphatic dicarboxylic acid species, 3 monosaccharide anhydrides, 3 steroids, and benzoic acid. The sources of these compounds were discussed.

Air Pollutants↗
PubMed1990

The covariation of chemical contamination, particulate matter and turbidity in soft polyvinyl chloride infusion fluid bags.

About 200 samples of normal saline, isotonic glucose and Ringer acetate infusions in soft polyvinyl chloride (PVC) bags obtained from three manufacturers have been analyzed by conductometric particle counting, turbidimetry and gas liquid chromatography (GLC). The particle counts were fitted to an exponentially modified log-normal model and integrated for total particle-volume. Di(2-ethylhexyl) phthalate (DEHP) and epoxidized vegetable oils (EVO), which are the main water insoluble contaminants in PVC fluid bags, were determined by GLC. There was a strong linear correlation between turbidity and GLC results. The correlation between particle-volume concentration and the DEHP and EVO concentrations was fairly good. The results seem to verify that an emulsion of plastic additives is formed when soft PVC infusion fluid bags are shaken.

Chromatography, Gas↗
PubMed1990

Particulate matter contamination in the corneal stroma of severe eye burns in humans.

Corneal buttons obtained from keratoplasty were examined by energy dispersive x-ray analysis (EDXA) combined with scanning electron microscopy (SEM). This method enables to assay the mineral composition of minute parts of tissue samples identified in SEM images. Samples were cut from paraffin embedded corneae, deparaffinized in xylol, dried in aceton, critical-point desiccated, covered by evaporating with a thin layer of carbon and examined by SEM. In healthy human donor eyes, only some iron particles had been found. In the 22 patients samples high amounts of different particles were identified, materials from rubber stoppers, chromesteel, titanium pigments, talcum, barium and glass. Furthermore a lot of different metal particles containing varying amounts of Na, Mg, Al, Si, P, S, Cl, K, Ca, Fe, Cu, Cr, Zn, La and Ce were detected. Some particles may be caused by the initial trauma, others by therapy. Such contaminations might have supported leucocyte and fibrocyte invasion increasing the inflammatory reaction in the burnt cornea.

Corneal Stroma↗