Partitioning of copper onto suspended particulate matter in river waters

Suspended particles and river water from the Susquehanna River, White Clay Creek and the Delaware River were collected to experimentally study the partitioning of copper. The effects of many factors that may influence the partitioning coefficient (Kd) including pH, total suspended solids (TSS), total copper concentration ([Cu]T), dissolved organic matter (DOM), particulate organic matter (POM), hardness, and ionic strength were investigated by performing batch adsorption experiments. The results implied that organic matter binding sites in both the aqueous and solid phases play the most important role in controlling copper partitioning. Other major factors governing the partitioning are pH and TSS. Kd increases with pH in the pH range 3-8. TSS increases caused decreases in Kd values, which may be attributed to the decrease in the quantity of available binding sites caused by interparticle interactions, rather than by the redistribution of organic matter between solid and solution phases with the variation of TSS. Kd decreases slightly when total Cu concentration increases; however, Kd can be considered to be independent of Cu concentration when TSS is high. The effects of calcium competition and ionic strength on partitioning are small.     

Ultraviolet absorption properties of suspended particulate matter in untreated surface waters

Previous research has shown that wastewater disinfection using UV light can be impaired by attenuation of the UV light as it passes through particles to reach embedded and protected microorganisms. This study determined that the UV absorption (at 254 nm) of particles present in 10 untreated surface waters was similar to the absorption of wastewater particles. As such, it provides evidence that UV disinfection of surface waters during drinking water treatment may be impaired by the same mechanism if particles are present. The study also demonstrated that among the 10 untreated surface waters examined, there was no correlation between the UV absorption (254 nm) of the solid particulate material, total organic carbon, total suspended solids, turbidity, or UV absorbance (254) of the bulk water.     

Geochemistry of suspended particulate matter in two natural sedimentation basins of the river Rhine

Multivariate analysis procedures have been used to trace possible correlations between changes in the composition of particulate organics and changes in the ratios of trace metal contents of suspended matter present in two major sedimentation basins of the river Rhine. In both basins, seaward gradients are observed in the organic characteristics as well as in the trace metal “patterns”. These two phenomena are well correlated. For both basins the changes in the two types of characteristics can be explained by simultaneously operating processes of sedimentation, autochthonous production and sediment resuspension.     

许氏平鮋消化管上皮细胞及消化腺组织学和组织化学

对许氏平Sebastesschlegeli(Hilgendorf)消化管中的上皮细胞及消化腺进行了组织学及组织化学的研究。经光学显微镜和扫描电镜观察,口咽腔、舌和食道黏膜表面为复层扁平细胞,含有杯状细胞和味蕾,上皮细胞表面具微脊(微皱襞)。食道下段复层扁平细胞中夹有单层柱状细胞。胃黏膜表面为单层柱状细胞,细胞表面具顶板。胃贲门和盲囊部有丰富胃腺,盲囊底部和幽门部无胃腺。肠黏膜表面为单层柱状细胞,小肠段杯状细胞丰富,幽门盲囊上皮细胞结构同小肠。另外,还研究了肝脏、胰腺和胆囊的结构。     

Lipid composition of suspended particulate matter (SPM) in a southeastern blackwater stream

Suspended particulate matter (SPM) was collected seasonally for 1 yr at third- and fifth-order sites in a blackwater stream on the coastal plain in South Carolina. Fatty acids with carbon chain lengths from C(12)-C(32) were the most abundant component among the lipid classes examined with total concentrations varying from 8.5 to 60.2 microgL(-1). Unsaturated fatty acids predominated while significant concentrations of the even-chained saturated components C(24)-C(30) derived from cuticular plant waxes were also found. Concentrations of aliphatic alcohols, with carbon chain lengths between C(16) and C(30), ranged from 0.52 to 2.73 microgL(-1) and was dominated by the higher molecular weight compounds (C(22)-C(30)) derived primarily from cuticular plant waxes. Total hydrocarbon concentrations ranged from 0.35 to 5.66 microgL(-1) and showed no discernible trends with time or consistent difference between sites. The hydrocarbon assemblage observed indicates that these components are entirely of biogenic origin with no detectable anthropogenic contribution.The ratios of unsaturated to saturated fatty acids and cuticular to noncuticular fatty acids and alcohols at both stream locations indicate that the organic detritus associated with SPM collected during November and January is of more recent origin and less processed than that collected in the spring and summer months. Lipid concentrations at the third-order site generally had higher and more variable concentrations of the lipid classes compared with the fifth-order site. The ratio of saturated to unsaturated fatty acids was higher at the third-order site indicating that the organic fraction of SPM at this site was of more recent origin and less decomposed. The ratios of cuticular to noncuticular fatty acids and alcohols support this conclusion. These results indicate an export of particulate lipids of higher carbon resource quality from upstream to lower stream reaches.     

Solid state partitioning of trace metals in suspended particulate matter from a river system affected by smelting-waste drainage

The partitioning of particulate trace metals was investigated during one year of monthly sampling of suspended particulate matter (SPM) at eight sites along the Lot-Garonne fluvial system, known for its polymetallic pollution. The chemical partitioning in five operationally defined fractions (exchangeable/carbonate, Fe/Mn oxides, organic matter/sulfides, acid soluble, residual) was determined using a multiple single extraction approach. This approach showed that Cd, Zn, Pb and Cu were mainly associated with acid soluble phases (84-95%, 65-88%, 61-82% and 55-80% of the respective total metal content), and therefore showed a high mean potential of mobilization and bioavailability. In the Riou-Mort River, draining the smelting-wastes, Zn, Cd and Mn showed high mobility as they were little associated with the residual fraction (1-2%) and mainly bound to the 'exchangeable' fraction of SPM (60-80%), probably weakly adsorbed on amorphous freshly-precipitated sulfide and/or oxide phases. Upstream and downstream of the anthropogenic source of metallic pollution, Mn and Cd, and Zn to a lesser extent, remained highly reactive. The other trace metals were mainly associated with the residual fraction and thus less mobile. However, the multiple single extraction scheme revealed that the most reactive transport phases were non-selectively extracted by the conventional extractants used here. These selectivity problems could not have been observed if sequential extraction was used.     

Polynuclear aromatic hydrocarbon content of particulate matter suspended in the atmosphere of La Plata, Argentina

Twelve polynuclear aromatic hydrocarbons (PAH) were evaluated by chromatographic procedures using a HPLC-UV detector and a GC-FID detector. The PAH were evaluated in airborne particulate matter collected in La Plata, Argentina, over a period of 2 years (with sampling periods of approximately 4 months). The samples were size fractionated, and the PAH in each fraction determined. The analytical procedure used was as follows: extraction in benzene, concentration at room temperature, clean-up in a silica gel column and, finally, evaluation by chromatographic procedures. The extraction recovery was 76.2 +/- 5.8% for naphthalene and 96.0 +/- 6.2% for chrysene. Clean-up recovery was 87.8 +/- 7.15% for phenanthrene and 98.1 +/- 8.3% for anthracene. The largest PAH load was present in the smallest fractions. The smallest particles were carbonaceous in nature. The concentration peak was associated both with the total mass of airborne particulate matter and the reduction in amounts of coarse particles. The PAH distribution could not be correlated with characteristic physicochemical properties such as water solubility or the octanol-water distribution coefficient. The PAH load was greater in fall and winter than in spring and summer. This could be attributed to the reduction of photochemical processes during the cold seasons.     

A study to characterize the suspended particulate matter in an indoor environment in Delhi,India

To investigate potential particulate matter (PM) exposure, and the possible effective measures for interventions and assessment of sources in indoor environments, a pilot study was conducted at Jawaharlal Nehru University (JNU), New Delhi. The indoor particles were collected from 5th April to 26th June 2000, using a tapered element oscillating microbalance (TEOM). The particles were analyzed by gravimetry, atomic absorption spectrometry (AAS) and scanning electron microscopy (SEM) in order to investigate the mass concentration, physico-chemical properties and morphology of the particles. The gravimetric and AAS results confirmed that the suspended particulate matter (SPM) and metal concentrations were higher than the National Ambient Air Quality Standards (NAAQS) for Delhi. The maximum contributions of SPM were observed to be due to wind-blown crustal dust and vehicular pollution. The SEM analysis of particles showed the presence of a variety of particles, but confirmed the dominance of silicon and soot particles.     

Relationship between ore deposits in river catchments and geochemistry of suspended particulate matter from six rivers in southwest France

Here we present original data on the geochemical composition of fluvial particulate matter transported by the rivers of the Adour/Garonne basin, which drains one-fifth of the French land surface. Suspended particulate matter from the six main rivers in the basin, sampled at 'normal' flow and during a flood, is compared in terms of: grain size; particulate organic carbon; Fe; Mn; and trace element concentrations (e.g. Zn, Cd, Pb, Cu, Mo, Sn, Ni, Co, Cr, V, As, Hg, U, Th, W, Au, Ag, Ta). Three of the six studied rivers (Garonne, Dordogne and Isle Rivers) are the main tributaries of the Gironde estuary (southwest France), known for Cd pollution. The Adour and Gaves Rivers enter the Adour Estuary and the Charente River reaches the ocean by the Charente Estuary. Our data show, that Cd (and Zn) are not the only trace elements of eco-toxicological relevance transported into the Gulf of Biscay by these six rivers. Potentially toxic elements (e.g. As, Sn, U, Cu, Ag) show elevated concentrations in river particulates entering the estuaries, compared to world average concentrations [Martin and Whitfield, 1983, The significance of the river input of chemical elements to the oceans. In: C.S. Wong, E. Boyle, K.W. Bruland, J.D. Burton, E.D. Goldberg (editors), Trace Metals in Sea Water, Plenum, New York: pp. 265-296]. Comparing SPM sampled during 'normal' discharge and flood, the basin shows a distinct trace element composition of SPM mostly related to ore deposits in the upper basins (Massif Central and Pyreneans). This geochemical signal is partly masked during floods due to changes in grain size, but also due to increased erosion of the lower parts of the basins. This study proves pumping/centrifugation to be the most appropriate sampling/separation technique (recovery, representativity, contamination) by comparing different methods of SPM recovery.     

Comparison between six different instruments to determine suspended particulate matter levels in ambient air

Over a period of six months simultaneous suspended particulate matter measurements with two different high volume samplers, two different low volume samplers, an automated dichotomous particulate system and an integrating Nephelometer were carried out at the same semi-rural monitoring site in the vicinity of the Nuclear Energy Research Centre, Mol, Belgium. Except for the nephelometer all SPM-determinations were done gravimetrically. The entire experiment was based on the comparison of daily averages.A reasonable to good correlation was found between the different instruments although the daily levels as well as the overall statistics of the SPM-situation over a period of six months showed large deviations. For certain instruments the deviations seemed to be systematic. The experiment will be repeated over another period of six months in order to control the present findings.     

The cadmium and lead content of suspended particulate matter emitted from a U.K. refuse incinerator

Suspended particulate matter (SPM), sampled from the stack of a large refuse incinerator in the U.K., contained markedly elevated levels of Cd (approximately 1600 micrograms g-1) and Pb (approximately 3%). These values were similar to those previously reported for several other incinerators in Europe, but the Pb concentrations were lower than in the SPM from three American incinerators. Calculation of the metal concentration ratio SPM/fly ash for the U.K. incinerator revealed a three-fold enrichment of the two metals on the SPM. Similar ratios were obtained for several other European incinerators; this correspondence in metal partitioning was linked to the use of electrostatic precipitators in these facilities. The SPM metal data obtained in this study were used to estimate atmospheric emissions of 0.5 t Cd year-1 and 11 t Pb year-1 from the incinerator. Extrapolation of the Cd and Pb emission factors derived from this study to the quantity of refuse incinerated in the U.K. results in atmospheric discharges of 6 t Cd year-1 and 115 t Pb year-1. These estimates are in good agreement with those previously reported by an emissions inventory which identified incineration as the single largest source of airborne Cd in the U.K.     

Natural, anthropogenic and fossil organic matter in river sediments and suspended particulate matter: a multi-molecular marker approach

Different classes of organic matter (OM) have been systematically investigated in sediments and suspended particulate matter (SPM) along the Danube River in order to understand causes of compositional changes. Analytical pyrolysis revealed the dominance of natural organic matter (NOM) in most of the samples. The predominance of aquatic biomass is evident mainly from the abundance of organonitrogen compounds and phenol distributions. As the river enters a forested gorge, the terrestrial component of the NOM in sediments is more significant. This is reflected in abundant methoxyphenols and a very high carbon preference index. SPM sample from a tributary shows a unique geochemical signature. It contains abundant carboxylic acids, amines, isoprenoids in the pyrolyzate, and is dominated by phytol and 24-methyl-cholesta-5,24(28)-dien-3β-ol in the extract, produced by a diatom bloom. Wax esters with a relatively high proportion of short, methyl-branched alkyl-chains appear together with abundant phytadienes and n-C₁₇ alkane in some samples, suggesting a microbial origin. Anthropogenic OM from runoff and atmospheric deposition was evident from a minor input of polycyclic aromatic hydrocarbons (PAHs) originating from mixed combustion sources. Multivariate analysis using PAH data led us to define simple molecular ratios to distinguish the PAH composition in sand and silty sediments. The newly defined ratios are the alkylated phenanthrenes and anthracenes ratio (APA; C₁-C₃/C₀-C₃ phenanthrenes and anthracenes) and the PAH ring number ratio (RN; 5-6 ring parent PAHs/all parent PAHs). This demonstrates that alkylated, as well as 5-6 ring PAHs are better preserved in the finer than in coarser grained sediments. A ubiquitous, but minor input of petroleum-related contamination with a uniform composition was evident in all samples as revealed by the analysis of petroleum biomarkers. This study demonstrates that the investigation of different classes of riverine OM requires a detailed molecular analysis, applying a series of analytical techniques and adequate statistical data treatment.     

基于Landsat 8的地表温度反演研究

为研究Landsat 8卫星TIRS传感器的第10通道和第11通道对地表温度反演的不同表现,以北京市为研究区,将单窗算法和普适性单通道算法分别应用到TIRS传感器的第10、11通道,并将这两种算法的反演结果与综合运用两个通道的劈窗算法反演结果进行比较,结果表明:(1)三种算法反演的结果总体趋势较为一致,中心高,边缘低;(2)两种单通道算法的反演精度普适性单通道算法优于单窗算法;(3)第10通道的反演结果要优于第11通道。     

Investigation of the impact of intensive broiler rearing on local fine particulate matter concentrations

During the review and assessment of air quality process, South Norfolk Council identified that poultry rearing could be a significant source of particulate matter and therefore required more detailed study. Using standard emission data for poultry rearing dispersion modelling confirmed that there was potential for an exceedance of the UK objective for fine particulate matter (PM₁₀). However, it was recognised that the emission data available were based on very limited information and further monitoring was required to investigate the issue fully. Accordingly, an air quality monitoring programme was set up to measure PM₁₀ concentrations around a large broiler‐rearing facility. This used both a TEOM‐ and Partisol‐type instrument to allow direct comparison with the UK objective and to provide continuous results to use with wind direction monitoring to assist in identifying the source of particulate matter in the area. The results from the monitoring showed that an exceedance of the UK objective was unlikely, although the broiler sheds did appear to result in a significant increase in PM₁₀ concentrations in the area, with average concentrations increasing by nearly 12 μg/m³ when the wind direction carried emissions from the sheds to the monitoring site. Given that the test site was located near a very large broiler farm, it was considered that it was unlikely that broiler‐rearing activities would result in an exceedance of the UK objective for PM₁₀.     

Quantitative filter forensics: Size distribution and particulate matter concentrations in residential buildings

We applied filter forensics, the analysis of dust from the heating, ventilation, and air-conditioning (HVAC) filters, to measure particle size distribution in 21 residences in Toronto, Canada over a year. Four filters with different nominal efficiencies (Minimum Efficiency Reporting Value (MERV) 8–14 from ASHRAE Standard 52.2) were deployed in each residence each for three months, while the effective filtration volumes (the product of flow rate, runtime, and in-situ filter efficiency) were characterized over each filter lifetime. Using extraction and laser diffraction, we found that approximately 90% of the volumetric distributions were >10 µm and the volume median diameter (VMD) ranged from 23.4 to 75.1 µm. Using quantitative filter forensics (QFF), total suspended particle (TSP) concentrations ranged from 2.9 to 823.7 µg/m³ (median = 89.8 µg/m³) with a moderate correlation with the content of TSP on the filters (in terms of g) and with the TSP effective filtration volume (m³) indicating the importance of both filter forensics and HVAC metadata parameters to QFF concentration estimates. There was no strong correlation between PM₁₀ or PM_2.5 concentrations and hourly airborne particle number concentrations measured by low-cost sensors suggesting an evaluation of QFF is warranted, particularly for the exploration of smaller particles.     

Effect-directed analysis of Ah receptor-mediated activities caused by PAHs in suspended particulate matter sampled in flood events

Suspended particulate matter (SPM) sampled during a flood event in the year 2004 at the rivers Neckar and Rhine (Southwest Germany) was assessed for aryl hydrocarbon receptor (AhR)-mediated activities using EROD induction in the rainbow trout liver cell line RTL-W1. All EROD inductions were normalized to the positive control TCDD and given as bio-TEQ values. Since all samples indicated elevated AhR-mediated toxicities, an effect-directed analysis (EDA) was applied to identify substances causing the effects. In three primary fractions (F1 to F3) non-polar aliphatics, non-polar aromatic substances and more polar substances were separated. Fraction F2, co-eluting with non-polar polyaromatic substances (PACs) including polycyclic aromatic hydrocarbons (PAHs) gave highest AhR-agonistic effects and, thus, were sub-fractionated into seven secondary fractions (F2-1 to F2-7). Fraction F2-1, co-eluting with PCBs and PCDD/Fs, did not cause AhR-agonist activities. F2-2 to F2-4 containing PACs of less than 16 aromatic C-atoms produced minor activities. Highest inductions were detected with fraction F2-5 to F2-7, containing substances of more than 16 aromatic C-atoms (bio-TEQs up to approximately 4500 pg/g).Concentrations and relative potencies (REPs) of priority EPA-PAHs allowed the calculation of chemical toxicity equivalent concentrations (chem-TEQ values). Based on the chem-TEQs, EPA-PAHs explained between 5 and 58% of crude extract bio-TEQs from both rivers. Whereas fractions F2-1 to F2-4 indicated no biological activities, EPA-PAHs in fraction F2-5 to F2-7 accounted for 2 to 137% of AhR-related activities.     

The influence of contrasting suspended particulate matter transport regimes on the bias and precision of flux estimates

A large database (507 station-years) of daily suspended particulate matter (SPM) concentration and discharge data from 36 stations on river basins ranging from 600 km(2) to 600,000 km(2) in size (USA and Europe) was collected to assess the effects of SPM transport regime on bias and imprecision of flux estimates when using infrequent surveys and the discharge-weighted mean concentration method. By extracting individual SPM concentrations and corresponding discharge values from the database, sampling frequencies from 12 to 200 per year were simulated using Monte Carlo techniques. The resulting estimates of yearly SPM fluxes were compared to reference fluxes derived from the complete database. For each station and given frequency, bias was measured by the median of relative errors between estimated and reference fluxes, and imprecision by the difference between the upper and lower deciles of relative errors. Results show that the SPM transport regime of rivers affects the bias and imprecision of fluxes estimated by the discharge-weighted mean concentration method for given sampling frequencies (e.g. weekly, bimonthly, monthly). The percentage of annual SPM flux discharged in 2% of time (Ms(2)) is a robust indicator of SPM transport regime directly related to bias and imprecision. These errors are linked to the Ms(2) indicator for various sampling frequencies within a specific nomograph. For instance, based on a deviation of simulated flux estimates from reference fluxes lower than +/-20% and a bias lower than 1% or 2%, the required sampling intervals are less than 3 days for rivers with Ms(2) greater than 40% (basin size<10,000 km(2)), between 3 and 5 days for rivers with Ms(2) between 30 and 40% (basin size between 10,000 and 50,000 km(2)), between 5 and 12 days for Ms(2) from 20% to 30% (basin size between 50,000 and 200,000 km(2)), 12-20 days for Ms(2) in the 15-20% range (basin size between 200,000 and 500,000 km(2)).     

Estimation of suspended sediment concentrations using Terra MODIS: An example from the Lower Yangtze River, China

Traditional measurements of suspended sediment concentrations (SSC) through in-situ sampling in rivers are expensive and time-consuming to perform. Thus, these methods cannot provide continuous SSC records. Although remote sensing has been used for SSC estimation, little research has been undertaken on inland rivers, especially for highly turbid rivers like the Yangtze. Previous studies have proposed Landsat TM/ETM+ Band 4 as a spectral SSC indicator for the Yangtze, but its limitation on temporal resolution is insufficient for the study of dynamic changes of sediment. This paper presents a method of estimating SSC of the Yangtze at Jiujiang using time-series satellite data of high temporal resolution Terra MODIS. It was found that differences in water reflectance between Band 2 and Band 5 could provide relatively accurate SSC estimation even when in-situ atmospheric conditions were unknown. After cross-validation, mean absolute relative error (ARE) and relative root mean square error (RRMSE) were relatively low (i.e., 25.5% and 36.5%, respectively). This empirical relationship was successfully applied to the estimation of SSC at Datong in the Lower Yangtze River, although the SSC values were generally underestimated. This study suggests that Terra MODIS could be used to estimate SSC in large turbid rivers, although some influencing factors require further study to improve the accuracy of SSC estimation.     

In-flight particulate matter concentrations in commercial flights are likely lower than other indoor environments

Air quality in indoor environments can have significant impacts on people's health, comfort, and productivity. Particulate matter (PM; also referred to as aerosols) is an important type of air pollutant, and exposure to outdoor PM has been associated with a variety of diseases. In addition, there is increasing recognition and concern of airborne transmission of viruses, including severe acute respiratory syndrome corona-virus 2 (SARS-CoV-2), especially in indoor environments. Despite its importance, indoor PM data during the COVID-19 pandemic are scarce. In this work, we measured and compared particle number and mass concentrations in aircraft cabins during commercial flights with various indoor environments in Atlanta, GA, during July 2020, including retail stores, grocery stores, restaurants, offices, transportation, and homes. Restaurants had the highest particle number and mass concentrations, dominated by cooking emissions, while in-flight aircraft cabins had the lowest observed concentrations out of all surveyed spaces.