Patterns of atmospheric nitrates,sulfate, and hydrogen chloride in the central Ohio River Valley over a one-year period

A study of the seasonal distribution of gaseous and particulate nitrate, sulfate, and hydrogen chloride in the central Ohio Valley is reported. The Ohio Valley has been identified as a significant source of the precursors to atmospheric acids which may be deposited hundreds of kilometers downwind from the source region. This study was undertaken to provide information on the concentration patterns of several species important in acidic deposition. Filter pack samples were collected for 24 h once each week (with some exceptions) from October 1979 through October 1980. The mean concentrations were: 4.05 μg/m³ sulfate, 3.76 μg/m³ total inorganic nitrate (TIN), 2.11 μg/m³ particulate nitrate (apparent), and 1.65 μg/m³ gaseous nitric acid (apparent). Other recent studies in the Ohio Valley yielded gaseous organic nitrate (PAN) concentrations of 2.3 μg/m³ in the spring and 4.8 μg/m³ in summer. Sulfate concentrations were highest in the summer, and both nitric acid and total inorganic nitrate levels were highest in spring and summer. The HNO₃/TIN ratio was also highest during warm weather. A limited number of samples were analyzed for gaseous hydrogen chloride. The concentration of HCl averaged 0.53 μg/m³ over a 2-month period. On a molar basis, HCl and HNO₃ concentrations were nearly equivalent over the 2-month period, suggesting that more attention should be paid to the role of HCl in atmospheric deposition.     

Investigation of volatile organic compounds and phthalates present in the cabin air of used private cars

The presence of selected volatile organic compounds (VOCs) including aromatic, aliphatic compounds and low molecular weight carbonyls, and a target set of phthalates were investigated in the interior of 23 used private cars during the summer and winter. VOC concentrations often exceeded levels typically found in residential indoor air, e.g. benzene concentrations reached values of up to 149.1 µg m^− 3. Overall concentrations were 40% higher in summer, with temperatures inside the cars reaching up to 70 °C. The most frequently detected phthalates were di-n-butyl-phthalate and bis-(2-ethylhexyl) phthalate in concentrations ranging from 196 to 3656 ng m^− 3.     

Aluminum, iron, and lead content of respirable particulate samples from a personal monitoring study

Samples of respirable particulate matter collected during a personal monitoring study in Topeka, KS, were analyzed for iron, aluminum, and lead content. The sampling protocol and instrumentation are described in detail. Lead indoor concentrations (median = 79 ng/m³) were found to be less than both personal (median = 112 ng/m³) and outdoor lead concentrations (median = 106 ng/m³). The indoor, outdoor, and personal levels of iron and aluminum were not significantly different. In addition, it was determined that outdoor respirable particulate mass does not correlate well with the personal or indoor metal concentrations, and that the amount of time spent in motor vehicles is a relatively good indicator of lead exposures. The relationships between indoor, outdoor, and personal lead are discussed in greater detail, with references to supporting evidence from other studies.     

Seasonal variation in outdoor,indoor, and personal air pollution exposures of women using wood stoves in the Tibetan Plateau: Baseline assessment for an energy intervention study

Cooking and heating with coal and biomass is the main source of household air pollution in China and a leading contributor to disease burden. As part of a baseline assessment for a household energy intervention program, we enrolled 205 adult women cooking with biomass fuels in Sichuan, China and measured their 48-h personal exposure to fine particulate matter (PM_2.5) and carbon monoxide (CO) in winter and summer. We also measured the indoor 48-h PM_2.5 concentrations in their homes and conducted outdoor PM_2.5 measurements during 101 (74) days in summer (winter). Indoor concentrations of CO and nitrogen oxides (NO, NO₂) were measured over 48-h in a subset of ~ 80 homes. Women's geometric mean 48-h exposure to PM_2.5 was 80 μg/m³ (95% CI: 74, 87) in summer and twice as high in winter (169 μg/m³ (95% CI: 150, 190), with similar seasonal trends for indoor PM_2.5 concentrations (winter: 252 μg/m³; 95% CI: 215, 295; summer: 101 μg/m³; 95% CI: 91, 112). We found a moderately strong relationship between indoor PM_2.5 and CO (r = 0.60, 95% CI: 0.46, 0.72), and a weak correlation between personal PM_2.5 and CO (r = 0.41, 95% CI: − 0.02, 0.71). NO₂/NO ratios were higher in summer (range: 0.01 to 0.68) than in winter (range: 0 to 0.11), suggesting outdoor formation of NO₂ via reaction of NO with ozone is a more important source of NO₂ than biomass combustion indoors. The predictors of women's personal exposure to PM_2.5 differed by season. In winter, our results show that primary heating with a low-polluting fuel (i.e., electric stove or wood-charcoal) and more frequent kitchen ventilation could reduce personal PM_2.5 exposures. In summer, primary use of a gaseous fuel or electricity for cooking and reducing exposure to outdoor PM_2.5 would likely have the greatest impacts on personal PM_2.5 exposure.     

Experimental studies of the transfer of neptunium from sea water to sediments and organisms (annelids and molluscs)

This paper deals with the physico-chemical behaviour of neptunium in sea water and with its capacity for transfer to coastal or deep-sea sediments and for uptake by two benthic species, Arenicola marina (L.) and Cerastoderma edule (L.). We used the ²³⁹Np isotope with mass concentrations in sea water of about 2·5 × 10⁻¹⁰−5·4×10⁻¹² g litre⁻¹, which are close to the concentrations observed in the environment for ²³⁷Np. The experimental results show that Np occurs in solution mainly as the neptunyl ion NpO₂⁺, but soluble anionic and neutral complexes and particulate forms were also detected. The distribution coefficients for the sediments varied from 350 to 6500. The carbonate phase plays a decisive role in neptunium transfer but other fixation processes are also possible. Concentration factors after 13 days were found to have values of 40 and 14 for the shells and soft parts of cockles, respectively, while polychaetes had a concentration factor of 2. Thus Np has a smaller probability of transfer to sediments and organisms than have plutonium and americium.     

Occurrence and behaviour of radionuclides in the Moselle River—Part III: Dispersion of radionuclides along the river course

Knowledge about propagation of radionuclides from nuclear power plants (NPPs) along the course of a river is of great interest in radioecological assessments. By use of a model previously applied in the cases of the Rhine and Weser Rivers, the distribution of various radionuclides released into the Moselle from the NPP Cattenom at normal operation is described with ⁵⁸Co, ⁶⁰Co and ^110mAg as tracers. A comparison of field measurements with calculated values revealed that the radionuclide concentrations in suspended matter and nuclide loads calculated from emission rates agreed with the measured data by a factor of less than two on average.Radionuclide concentrations and loads along the river course decrease mainly due to deposition of particulate radioactive matter in high-sedimentation areas and due to dilution with uncontaminated material from tributaries and other sources. The rate constants of both processes were evaluated, and the mean range of suspended radioactive particles in the Moselle was estimated. Moreover, this study showed anew that suspended matter has to be considered as the main carrier by which the radionuclides from NPPs may be transported over long distances.     

Sidestream tobacco smoke constituents in indoor air modelled in an experimental chamber— Polycyclic aromatic hydrocarbons

Exposure to sidestream tobacco smoke is concerned with constituents in suspension in the indoor atmosphere. The natural dissipation of sidestream tobacco smoke has been investigated in a static atmosphere in a 10 m³ experimental chamber, and the rate of dissipation is expressed as T_0.5, the half-life of residence in the air. Respective T_0.5 of smoke components are calculated from the various sample data points, assuming a kinetic equation of the first-order process. Sidestream smoke has been generated by a smoking machine according to the Coresta standard protocol and then left to age over an 8-hour period, with subsequent sampling at defined time intervals. The experiments have been repeated over five days, and eight data point samples are obtained for each experiment. Besides nicotine, CO, and smoke particulate matter, interest has been focused on polycyclic aromatic hydrocarbons (PAH). The initial concentrations, C₀ for smoke particulate matter and nicotine (gas and particulate phases) are found to be 13.8 mg and 92 μg per cigarette per cubic meter, with T_0.5 being 2.6 and 2.1 hours, respectively. Low molecular-weight PAH have T_0.5 up to 20 hours, explainable only by their high concentrations in the gas phase, while the 3- to 7-ring PAH have T_0.5 of about 2 hours. The contribution of CO to ambient concentration is 91 mg per cigarette per cubic meter. The data can be useful in mathematical modellization studies regarding ventilation or exposure to sidestream smoke.     

Status and characteristics of ambient PM2.5 pollution in global megacities

Ambient PM_2.5 pollution is a substantial threat to public health in global megacities. This paper reviews the PM_2.5 pollution of 45 global megacities in 2013, based on mass concentration from official monitoring networks and composition data reported in the literature. The results showed that the five most polluted megacities were Delhi, Cairo, Xi'an, Tianjin and Chengdu, all of which had an annual average concentration of PM_2.5 greater than 89 μg/m³. The five cleanest megacities were Miami, Toronto, New York, Madrid and Philadelphia, the annual averages of which were less than 10 μg/m³. Spatial distribution indicated that the highly polluted megacities are concentrated in east-central China and the Indo-Gangetic Plain. Organic matter and SNA (sum of sulfate, nitrate and ammonium) contributed 30% and 36%, respectively, of the average PM_2.5 mass for all megacities. Notable seasonal variation of PM_2.5 polluted days was observed, especially for the polluted megacities of China and India, resulting in frequent heavy pollution episodes occurring during more polluted seasons such as winter. Marked differences in PM_2.5 pollution between developing and developed megacities require more effort on local emissions reduction as well as global cooperation to address the PM_2.5 pollution of those megacities mainly in Asia.     

Upper respiratory symptoms presumably due to studded tire-generated dust

The particulate concentrations in ambient air was elevated in winter seasons in the center of the city of Sendai, presumably due to the extensive use of the studded tires for automobiles; the levels of 493 and 212 μg/m³ were recorded for total particulates and respirable particulates, respectively. The subjective symptom prevalence was investigated by means of self-completion questionnaires in January–February 1984, among the ≥40-yr-old inhabitants of both sexes in the center of Sendai city (annual average total particulate concentration, 28 μg/m³) and also in two whole townships of Wakuya and Tajiri where the air was clean (annual average total particulate concentration, 14 μg/m³). About 17400, 8500, and 6200 respondents were obtained from Sendai, Wakuya, and Tajiri, with an average response rate of 87%. The survey was repeated again in September–October of the same year utilizing one-eighth of the first survey respondents with the response rate of 78%. The analyses of the January–February survey results after adjustment for age and smoking disclosed that prevalence rates of the upper respiratory symptoms such as rhinorrhea, frequent sneezing, phlegm, and sore throat were significantly higher (p < 0.01 ∼ 0.05 depending on the symptoms) among the Sendai population than the control populations in Wakuya and Tajiri in winter. Similar comparative analyses of responses in the September–October survey revealed that the differences in the prevalence rates of the above-stated symptoms did not exist in autumn when the particulate concentrations were low also in Sendai. Possible association of the observed symptoms with elevated particulate concentrations are discussed.     

Fallout distribution in Padua and Northeast Italy after the chernobyl nuclear reactor accident

The radioactive cloud from the Chernobyl nuclear reactor accident arrived in northeast Italy on 30 April 1986. Ground-level air activities detected in Padua reached maximum values of 28·6, 19·2, 3·3, 1·7 and 7·5 Bq m⁻³ for ¹³¹I, ¹³²Te(¹³²I), ¹³⁷Cs and ¹⁰³Ru, respectively, on 1 May; about 10 days later, the activities had fallen to less than 1% of peak values. Considerations of cloud homogeneity are reported.The distribution of fallout radionuclides in Padua was evaluated on the basis of radioactivity detected on natural surfaces. The average committed dose equivalent to the thyroid for adult people in Padua through ¹³¹I inhalation was estimated at 0·37 mSv. Soil activity was monitored daily in samples collected in Padua during the first weeks of May 1986. Fallout deposition over northeast Italy was measured on 75 surface soil samples collected during June 1986 and long-lived radionuclide distribution maps were derived.     

Long-term effects of elemental composition of particulate matter on inflammatory blood markers in European cohorts

BackgroundEpidemiological studies have associated long-term exposure to ambient particulate matter with increased mortality from cardiovascular and respiratory disorders. Systemic inflammation is a plausible biological mechanism behind this association. However, it is unclear how the chemical composition of PM affects inflammatory responses.ObjectivesTo investigate the association between long-term exposure to elemental components of PM and the inflammatory blood markers high-sensitivity C-reactive protein (hsCRP) and fibrinogen as part of the European ESCAPE and TRANSPHORM multi-center projects.MethodsIn total, 21,558 hsCRP measurements and 17,428 fibrinogen measurements from cross-sections of five and four cohort studies were available, respectively. Residential long-term concentrations of particulate matter < 10 μm (PM₁₀) and < 2.5 μm (PM_2.5) in diameter and selected elemental components (copper, iron, potassium, nickel, sulfur, silicon, vanadium, zinc) were estimated based on land-use regression models. Associations between components and inflammatory markers were estimated using linear regression models for each cohort separately. Cohort-specific results were combined using random effects meta-analysis. As a sensitivity analysis the models were additionally adjusted for PM mass.ResultsA 5 ng/m³ increase in PM_2.5 copper and a 500 ng/m³ increase in PM₁₀ iron were associated with a 6.3% [0.7; 12.3%] and 3.6% [0.3; 7.1%] increase in hsCRP, respectively. These associations between components and fibrinogen were slightly weaker. A 10 ng/m³ increase in PM_2.5 zinc was associated with a 1.2% [0.1; 2.4%] increase in fibrinogen; confidence intervals widened when additionally adjusting for PM_2.5.ConclusionsLong-term exposure to transition metals within ambient particulate matter, originating from traffic and industry, may be related to chronic systemic inflammation providing a link to long-term health effects of particulate matter.     

Depositional behaviors of plutonium and thorium isotopes at Tsukuba and Mt. Haruna in Japan indicate the sources of atmospheric dust

Monthly plutonium and thorium depositions at Tsukuba (28 m asl) and Mt. Haruna (1370 m asl) were measured during 2006 and 2007 (Jan 2006-Dec 2007 at Tsukuba, Nov 2006-Dec 2007 at Mt. Haruna). The monthly ^239,240Pu depositions ranged from 0.044 to 2.67 mBq m⁻² at Tsukuba and from 0.05 to 0.9 mBq m⁻² at Mt. Haruna during the measurement periods. Monthly ^239,240Pu deposition did not differ markedly between the two sites except in April 2007. Seasonal pattern of monthly ^239,240Pu depositions at both sites showed high in spring and low in summer, and typical of seasonal variations in northeastern Asia. Thorium deposition at Tsukuba was higher than that at Mt. Haruna except in May and June 2007. ²³⁰Th/²³²Th activity ratios were used to partition deposition samples into locally and remotely derived fractions. The results revealed that a major proportion of total ^239,240Pu and Th deposits are derived from remote sources, especially in spring.     

Fallout in the New York metropolitan area following the chernobyl accident

In the metropolitan New York area, maximum concentrations in air of radioactive aerosol and gaseous debris from the Chernobyl accident of April 1986 were much lower than those measured in Europe. The observed maxima were: for gaseous ¹³¹I, 23mBq m⁻³; for aerosol samples, 20mBq m⁻³ of ¹³¹I and 9·mBq m⁻³ of ¹³⁷Cs. The data suggest that little gas-to-particle transformation of iodine occurred during transport of the radioactive cloud from the Ukraine to New York. The ratios of ¹⁰³Ru and other refractories to ¹³⁷Cs were low in the first debris sampled, debris which probably was emitted from Chernobyl in late April during the early stages of the accident. In subsequent samples these ratios were higher, presumably because debris from the later, hotter stages of the fire had reached our sampling sites. A significant fraction (25–40%) of the deposition of ¹³¹I and ¹³⁷Cs into our samplers and on grass was by dry deposition. The total deposition of Chernobyl ¹³⁷Cs in the area was <1% of that already present in the soil from fallout from past nuclear weapon tests. The highest concentration of ¹³¹I measured in fresh milk was about 1.5 B1 liter⁻¹, <0.1% of the US action level. The dose to the thyroid of a six-month-old infant who had fresh milk as a sole food source would be about 70 μGy (7 mrad).     

Smoke-haze pollution: a review of the 1997 episode in Southeast Asia

In the second half of 1997, large areas in Southeast Asia were severely affected by a smoke-haze pollution episode caused by the emissions of an estimated 45,600 km² of vegetation that burnt on the Indonesian islands Kalimantan and Sumatra. To document the impacts of these fires on air quality, data for total suspended particulate matter (TSP) and for particulate matter below or equal to 10 microns in diameter (PM₁₀) from selected sites in Indonesia, Malaysia and Singapore are analysed in this paper. These data are supplemented by meteorological data, satellite images and a summary of related research. TSP was above 2,000 μg m^–3 for several days in Indonesian locations close to the most extensive fire activity. In Malaysia and Singapore, ambient particle concentrations increased to several times their average September levels. Characteristically for emissions from vegetation burning, the additional atmospheric particle loading during the smoke-haze episode was predominantly due to an increase of the fraction below or equal to 2.5 microns in diameter (PM_2.5). Due to the dominance of respirable particles (PM_2.5) in the smoke-haze, air quality reporting based on TSP or PM₁₀ may be inadequate to assess the health risk. Upgrading of PM_2.5 monitoring facilities is therefore needed. Reducing the probability of similar smoke-haze events in future would require appropriate fire use and smoke management strategies. Electronic Publication     

Scavenging of 234Th in the Eastern Irish Sea

Measurements of the disequilibria of ²³⁴Th/²³⁸U in seawater and in suspended particulate and seabed sediment in the eastern Irish Sea reveal that the residence time of dissolved ²³⁴Th (0·5–7·7 days) is controlled by the concentration of particles in suspension (0·4–6·9 mg litre⁻¹, which reflects the rate of sediment resuspension (0·5–5·9 kg m⁻²y⁻¹). The residence time of ²³⁴Th with respect to removal to the seabed is longer (7–50 d) and is less dependent on variations in the suspended load. Anthropogenic sources of ²³⁸U contribute up to 8–15% of the water column production of ²³⁴Th. Enhanced scavenging occurs near the coast and there appears to be a net horizontal flux of ²³⁴Th within this region.     

Introduction to and experimental conditions during the first year of the GMR chronic inhalation studies of diesel exhaust

A chronic exposure study was initiated to determine the effects of diesel exhaust on the health of experimental animals. For this purpose, test atmospheres of clean air (control) or freshly diluted diesel exhaust at concentrations of 250, 750, and 1500 μg/m³ were supplied to four 12.6 m³ inhalation chambers which housed rats and guinea pigs. Diesel aerosol size and concentration, as well as chamber temperature and relative humidity, were continually monitored and controlled to maintain the exposure dose levels and an environment of 22±2°C and 50%±20% relative humidity. The concentrations of CO and NO_x were found to be 5.8±1.0 mg/m³ and 7.9±1.0 mg/m³ above ambient in the chamber containing 1500 μg/m³ of particulate. Animals were supplied from the chambers, on a random basis, for both intramural and extramural studies throughout the exposure period. The experiment ran uninterrupted for over twelve months with mean diesel particle mass concentrations within 2% of the target values.     

Chemical characteristics of precipitation and wet deposition of major ions in Liaozhong County of Liaoning Province,Northeast China

The chemical characteristics of precipitation were analyzed based on the chemical composition of principal ionic within acid rain（from February 2007 to January 2008）of Liaozhong Meteorological Station located in Malong Village in Liaozhong County of Northeast China,meteorological conditions on the corresponding period ground,and variation of several air pollutants concentration.The results indicated that:（1）The precipitation average pH value of all samples was4.76;the frequency of acid rain during the observation period was 70.7%;the frequency was 82.8%in summer and autumn.（2）In the chemical composition of precipitation,the primary anions were SO₄^2-and NO₃^-;the primary cations were NH₄⁺and Ca²⁺.（3）All concentration of anions was higher in summer and winter,but relatively low in spring and autumn.This showed that the relationship between regional rainfall acidification and pollution was not significant.（4）Rainwater acidity and nearly floor gaseous pollution concentration were different from each other,and pH and NO_x,CO,NO₂ and O₃concentrations showed significant negative correlation,but was not obvious with SO₂ concentration.However,the pH and alkaline pollutants,such as particulate,was positively correlative.     

Activity concentrations of 226Ra, 228Ra, 210Pb, 40K and 7Be and their temporal variations in surface air

Activity concentrations of the long-lived natural radionuclides ²²⁶Ra, ²²⁸Ra, ²¹⁰Pb, ⁴⁰K and of ⁷Be in surface air were measured twice monthly at a semi-rural location 10 km north of Munich (FRG) for at least three years. For the time interval 1983–1985, all values were found to be distributed log-normally, with geometric means (in μBq m⁻³) of 1·2 for ²²⁶Ra, 0·5 for ²²⁸Ra, 580 for ²¹⁰Pb, 12 for ⁴⁰K and 3500 for ⁷Be. Reflecting their common origin, the activity concentrations of ²²⁶Ra and ⁴⁰K are correlated with surface air dust concentrations (geometric mean 59 μg m⁻³). Seasonal variations of ²¹⁰Pb and ⁷Be air activity concentrations are established for the time interval 1978–1985.The contribution of local soil activity to the air activity concentrations of these radionuclides and of natural uranium is discussed. Resuspension factors are found to be of the order of 10⁻⁹m⁻¹.     

99Tc in the sub-arctic food chain Lichen-Reindeer-man

The deposition, migration and annual variations of ⁹⁹Tc fallout in carpets of lichen collected during the period 1956–1981 have been investigated. The transfer of ⁹⁹Tc to reindeer and man has also been studied. Technetium showed a shorter mean residence time than ¹³⁷Cs in the lichen carpet. The activity ratio ⁹⁹Tc/¹³⁷Cs was generally lower than the theoretical fission ratio of 1·43 × 10⁻⁴. The maximum concentration of ⁹⁹Tc in lichens occurred in 1967 (ca. 60 mBq kg⁻¹) but in 1975 higher values were found than would have been predicted from fallout. The average depth integrated concentration of ⁹⁹Tc at 62·3°N, 12·4° E in 1972 was 540 ± 100 mBq m⁻². The studies of reindeer tissues show that technetium has a short mean residence time in the muscle tissues (ca. 5 days) and is not accumulated like ¹³⁷Cs. The committed dose equivalent from ⁹⁹Tc to the local Lapp population engaged in reindeer breeding is negligible.     

Air-to-vegetation transfer rates of natural submicron aerosols

Submicron aerosol deposition to outdoor vegetation was evaluated by measuring vegetation and air concentrations of ²¹²Pb, ²¹⁴Pb, and ⁷Be attached to atmospheric aerosols. A biomass-normalized deposition velocity (V_D), with units of m³ kg^?1 s^?1, was used to compare species and isotopes with respect to air-to-vegetation transfer rates. For ²¹²Pb ($\text{t}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 10·64 h}$), higher night-time air concebtrations dominate deposition, while for ²¹⁴Pb ($\text{t}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 26·8}\text{min}$), deposition measurements over shorter time periods relative to changing atmospheric conditions were possible. Calculated V_D values were usually higher for ²¹⁴Pb, possibly reflecting wind-enhanced deposition during the afternoon period of sampling. Evergreen species, including pines, were not appreciably different from deciduous species. Most striking was the narrow range of results (factor of 6 for 34 ²¹²Pb measurements of 20 species). Beryllium-7 ($\text{t}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 53·3 d}$) was used to evaluate time-integrated deposition by sampling vegetation in California near the end of dry summers. Similar deposition rates were found for this isotope. The results of the study indicated that naturally radioactive atmospheric aerosols can be used to understand the dynamics of submicron aerosol deposition to ecosystems.