Early wheezing phenotypes and severity of respiratory illness in very early childhood: Study on intrauterine exposure to fine particle matter

The main goal of the paper was to assess the pattern of risk factors having an impact on the onset of early wheezing phenotypes in the birth cohort of 468 two-year olds and to investigate the severity of respiratory illness in the two-year olds in relation to both wheezing phenotypes, environmental tobacco smoke (ETS) and personal PM_2.5 exposure over pregnancy period (fine particulate matter). The secondary goal of the paper was to assess possible association of early persistent wheezing with the length of the baby at birth. Pregnant women were recruited from ambulatory prenatal clinics in the first and second trimester of pregnancy. Only women 18–35 years of age, who claimed to be non-smokers, with singleton pregnancies, without illicit drug use and HIV infection, free from chronic diseases were eligible for the study. In the statistical analysis of respiratory health of children multinomial logistic regression and zero-inflated Poisson regression models were used. Approximately one third of the children in the study sample experienced wheezing in the first 2 years of life and in about two third of cases (67%) the symptom developed already in the first year of life. The early wheezing was easily reversible and in about 70% of infants with wheezing the symptom receded in the second year of life. The adjusted relative risk ratio (RRR) of persistent wheezing increased with maternal atopy (RRR = 3.05; 95%CI: 1.30–7.15), older siblings (RRR = 3.05; 95%CI: 1.67–5.58) and prenatal ETS exposure (RRR = 1.13; 95%CI: 1.04–1.23), but was inversely associated with the length of baby at birth (RRR = 0.88; 95%CI: 0.76–1.01). The adjusted incidence risk ratios (IRR) of coughing, difficult breathing, runny/stuffy nose and pharyngitis/tonsillitis in wheezers were much higher than that observed among non-wheezers and significantly depended on prenatal PM_2.5 exposure, older siblings and maternal atopy. The study shows a clear inverse association between maternal age or maternal education and respiratory illnesses and calls for more research efforts aiming at the explanation of factors hidden behind proxy measures of quality of maternal care of babies. The data support the hypothesis that burden of respiratory symptoms in early childhood and possibly in later life may be programmed already in prenatal period when the respiratory system is completing its growth and maturation.     

Synthesis of isotopically modified ZnO nanoparticles and their potential as nanotoxicity tracers

Understanding the behavior of engineered nanoparticles in the environment and within organisms is perhaps the biggest obstacle to the safe development of nanotechnologies. Reliable tracing is a particular issue for nanoparticles such as ZnO, because Zn is an essential element and a common pollutant thus present at elevated background concentrations. We synthesized isotopically enriched (89.6%) with a rare isotope of Zn (⁶⁷Zn) ZnO nanoparticles and measured the uptake of ⁶⁷Zn by L. stagnalis exposed to diatoms amended with the particles. Stable isotope technique is sufficiently sensitive to determine the uptake of Zn at an exposure equivalent to lower concentration range (<15 μg g⁻¹). Without a tracer, detection of newly accumulated Zn is significant at Zn exposure concentration only above 5000 μg g⁻¹ which represents some of the most contaminated Zn conditions. Only by using a tracer we can study Zn uptake at a range of environmentally realistic exposure conditions.     

Unexpected difference in phenol sorption on PTMA- and BTMA-bentonite

The comparison of phenol sorption on phenyltrimethylammonium (PTMA)- and benzyltrimethylammonium (BTMA)-bentonite shows a clear difference as far as phenol sorption isotherms are concerned. For PTMA-bentonite the sorption isotherm is of a straight-line character which results from simple partitioning of phenol between the aqueous and organic phases sorbed on the bentonite surface. For BTMA-bentonite the isotherm has a convex shape, characteristic of physicochemical sorption.For the first time a three-parametric model, including the dissociation constant of phenol pK_a, distribution constant of phenol Kd_phen and phenolate anion Kd_phen⁻ between the aqueous phase and the bentonite phases is used for the evaluation of phenol sorption on organoclays with pH change. The model shows that the values of Kd_phen are higher than those of Kd_phen⁻ for all investigated initial phenol concentrations.The inspection of the FTIR spectrum of BTMA-bentonite loaded with phenol in the regions 1300–1600 and 1620–1680 cm⁻¹ shows the features of π–π electron interaction between the benzene rings of phenol and the BTMA cation together with the phenol–water hydrogen bond strengthened by this interaction.     

Beyond contaminated land assessment: On costs and benefits of bioaccessibility prediction

Advances towards sustainable land management necessitate application of a broader portfolio of decision-support tools that improve evaluation of contaminated land. Over the last decade regulators have directed concerted effort towards rationalization of risk-based contaminated land policies recognizing bioavailability and bioaccessibility as concepts to be incorporated into risk assessments. The desire for a precise and rapid method to inform consideration of bioavailability and bioaccessibility to support risk assessment of contaminated land has never been greater. This study presents a comprehensive appraisal of both emerging non-exhaustive extraction techniques (subcritical water extraction and Brij 700 extraction) developed to reflect polycyclic aromatic hydrocarbon (PAH) bioaccessibility to microorganisms as well as formerly demonstrated methodologies (the use of cyclodextrins and butanol extraction). Application of unified evaluation criteria across different techniques enabled comparison not only from the bioaccessibility prediction perspective but also analysis of economical (cost of extraction) and practical (such as extraction time) measures. Whilst the use of cyclodextrins was the best predictor of the bioaccessible fraction for the majority of compounds, other methods appeared more cost- and time-effective. Juxtaposition of the techniques presented in this study assists establishing cost-benefit trade-offs of different non-exhaustive extraction techniques and contributes to tailoring information on contaminant bioaccessibility to support risk evaluation on contaminated sites.     

Interspecies and interregional comparisons of the chemistry of PAHs and trace elements in mosses Hylocomium splendens (Hedw.) B.S.G. and Pleurozium schreberi (Brid.) Mitt. from Poland and Alaska

Comparative biogeochemical studies performed on the same plant species in remote areas enable pinpointing interspecies and interregional differences of chemical composition. This report presents baseline concentrations of PAHs and trace elements in moss species Hylocomium splendens and Pleurozium schreberi from the Holy Cross Mountains (south-central Poland) (HCM) and Wrangell–Saint Elias National Park and Preserve (Alaska) and Denali National Park and Preserve (Alaska). Total PAH concentrations in the mosses of HCM were in the range of 473–2970 μg kg^?1 (dry weight basis; DW), whereas those in the same species of Alaska were 80–3390 μg kg^?1 DW. Nearly all the moss samples displayed the similar ring sequence: 3 > 4 > 5 > 6 for the PAHs. The 3 + 4 ring/total PAH ratios show statistically significant differences between HCM (0.73) and Alaska (0.91). The elevated concentrations of PAHs observed in some sampling locations of the Alaskan parks were linked to local combustion of wood, with a component of vehicle particle- and vapor-phase emissions. In HCM, the principal source of PAH emissions has been linked to residential and industrial combustion of coal and vehicle traffic. In contrast to HCM, the Alaskan mosses were distinctly elevated in most of the trace elements, bearing a signature of the underlying geology. H. splendens and P. schreberi showed diverse bioaccumulative capabilities of PAHs in all three study areas.     

Concentration,sources and risk assessment of PAHs in bottom sediments

Environmental Science and Pollution Research - The aims of the study were to investigate the concentration, sources and ecological risk of PAHs (polycyclic aromatic hydrocarbons) in bottom...     

Comparison of two sample preparation methods for analysis of organochlorine pesticides residues in fish muscle

The aim of this study was to compare recoveries of organochlorine pesticides (heptachlor, α-HCH, β-HCH, γ-HCH, op′-DDD, pp′-DDD, pp′-DDE, op′-DDT, pp′-DDT) from fish muscle dried by two alternative methods: (i) grinding with anhydrous sodium sulphate and (ii) freeze drying. Pesticide residues content was determined by gas chromatography-mass spectrometry (GS-MS) method. For four pesticides (γ-HCH, α-HCH, heptachlor and pp;-DDD) in four of five fish species, higher recoveries were obtained from the freeze-dried samples. For five remaining pesticides, correlations between fish species and drying method were not found. The results of this study do not clearly indicate which drying method caused lower losses of analytes. Recoveries from the freeze-dried samples ranged from 69.9 to 117.6 %, while recoveries from the samples ground with sodium sulphate varied from 64.4 to 126.7 %. Either of the methods gave satisfactory recoveries and they both can be used interchangeably.