The health impacts of suspended particulate matter (SPM) are significantly associated with size-the smaller the aerosol particles, the stronger the biological effect. Quantitative evaluation of fine and ultrafine particles (FP and UFP) is, therefore, an integral part of ongoing epidemiological studies. The mass concentrations of SPM fractions (especially PM2.5, PM1.0, PM0.25) were measured in an industrial area using cascade personal samplers and a gravimetric method, and their mass ratio was determined. The results of PM2.5, PM1.0 were also compared with the reference measurement at stationary stations. The mean ratios PM2.5/SPM, PM1.0/SPM, and PM1.0/PM2.5 were 0.76, 0.65, and 0.86, respectively. Surprisingly, a mass dominance of UFP with an aerodynamic diameter <0.25 μm (PM0.25) was found with mean ratios of 0.43, 0.57, 0.67 in SPM, PM2.5 and PM1.0. The method used showed satisfactory agreement in comparison with reference measurements. The respirable fraction may consist predominantly of UFP. Despite the measures currently being taken to improve air quality, the most biologically efficient UFP can escape and remain in the air. UFP are currently determined primarily as particle number as opposed to the mass concentration used for conventional fractions. This complicates their mutual comparison and determination of individual fraction ratios.

• Klíčová slova
• fine and ultrafine fraction, mass concentration, respirable fraction, suspended particulate matter,
• MeSH
• látky znečišťující vzduch * analýza   MeSH
• monitorování životního prostředí MeSH
• pevné částice analýza   MeSH
• prach MeSH
• velikost částic MeSH
• znečištění ovzduší * analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• látky znečišťující vzduch * MeSH
• pevné částice MeSH
• prach MeSH

BACKGROUND: Asthma represents a syndrome for which our understanding of the molecular processes underlying discrete sub-diseases (i.e., endotypes), beyond atopic asthma, is limited. The public health needs to characterize etiology-associated endotype risks is becoming urgent. In particular, the roles of polyaromatic hydrocarbon (PAH), globally distributed combustion by-products, toward the two known endotypes - T helper 2 cell high (Th2) or T helper 2 cell low (non-Th2) - warrants clarification. OBJECTIVES: To explain ambient B[a]P association with non-atopic asthma (i.e., a proxy of non-Th2 endotype) is markedly different from that with atopic asthma (i.e., a proxy for Th2-high endotype). METHODS: In a case-control study, we compare the non-atopic as well as atopic asthmatic boys and girls against their respective controls in terms of the ambient Benzo[a]pyrene concentration nearest to their home, plasma 15-Ft2-isoprostane (15-Ft2-isoP), urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), and lung function deficit. We repeated the analysis for i) dichotomous asthma outcome and ii) multinomial asthma-overweight/obese (OV/OB) combined outcomes. RESULTS: The non-atopic asthma cases are associated with a significantly higher median B[a]P (11.16 ng/m3) compared to that in the non-atopic controls (3.83 ng/m3; P-value < 0.001). In asthma-OV/OB stratified analysis, the non-atopic girls with lean and OV/OB asthma are associated with a step-wisely elevated B[a]P (median,11.16 and 18.00 ng/m3, respectively), compared to the non-atopic lean control girls (median, 4.28 ng/m3, P-value < 0.001). In contrast, atopic asthmatic children (2.73 ng/m3) are not associated with a significantly elevated median B[a]P, compared to the atopic control children (2.60 ng/m3; P-value > 0.05). Based on the logistic regression model, on ln-unit increate in B[a]P is associated with 4.7-times greater odds (95% CI, 1.9-11.5, P = 0.001) of asthma among the non-atopic boys. The same unit increase in B[a]P is associated with 44.8-times greater odds (95% CI, 4.7-428.2, P = 0.001) among the non-atopic girls after adjusting for urinary Cotinine, lung function deficit, 15-Ft2-isoP, and 8-oxodG. CONCLUSIONS: Ambient B[a]P is robustly associated with non-atopic asthma, while it has no clear associations with atopic asthma among lean children. Furthermore, lung function deficit, 15-Ft2-isoP, and 8-oxodG are associated with profound alteration of B[a]P-asthma associations among the non-atopic children.

• Klíčová slova
• 8-oxo-7,8-dihydro-2′-deoxyguanosine, Air pollution, Benzo[a]pyrene, Endotype;15-Ft2-isoprostane,
• MeSH
• 8-hydroxy-2'-deoxyguanosin moč   MeSH
• benzopyren analýza   MeSH
• bronchiální astma krev   epidemiologie   patofyziologie   moč   MeSH
• dinoprost analogy a deriváty   krev   MeSH
• dítě MeSH
• fenotyp MeSH
• kojenec MeSH
• kotinin moč   MeSH
• látky znečišťující vzduch analýza   MeSH
• lidé MeSH
• mladiství MeSH
• plíce patofyziologie   MeSH
• předškolní dítě MeSH
• studie případů a kontrol MeSH
• vystavení vlivu životního prostředí analýza   MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Názvy látek
• 8-epi-prostaglandin F2alpha MeSH Prohlížeč
• 8-hydroxy-2'-deoxyguanosin MeSH
• benzopyren MeSH
• dinoprost MeSH
• kotinin MeSH
• látky znečišťující vzduch MeSH

The effect of exposure to carcinogenic polycyclic aromatic hydrocarbons adsorbed onto respirable air particles (PM2.5, diameter < 2.5 μm) on DNA adducts and chromosomal aberrations was repeatedly studied in Prague, Czech Republic, in groups of policemen working in the downtown area and in bus drivers. Personal exposure was evaluated using personal samplers during working shifts. DNA adducts were analyzed in lymphocytes by the (32)P-postlabeling assay and chromosomal aberrations were analyzed by conventional cytogenetic analysis and fluorescent in situ hybridization (FISH). The impact of environmental pollution on DNA adducts and chromosomal aberrations was studied in a total of 950 subjects. Our results suggest that the environmental exposure of nonsmokers to concentrations higher than 1 ng benzo[a]pyrene/m(3) represents a risk of DNA damage, as indicated by an increase in DNA adducts and the genomic frequency of translocations determined by FISH.

• Publikační typ
• časopisecké články MeSH