Highway Dust Research Articles

Partitioning of heavy metals over different chemical fraction in street dust of Murcia (Spain) as a basis for risk assessment

Dust samples were collected from urban, suburban, industrial, highways, and natural sites from the vicinity of Murcia City, Spain. Chemical and physical properties were determined as well as the partitioning of the heavy metals Cu, Pb, Zn and Cd over exchangeable pools, association with carbonates, oxides, organic complexes and a residual phase.The results showed differences in the concentrations and percentages of the metals extracted from the five chemical phases among the dusts studied. These were attributed to the sources of metals, total metal concentration, dust physical and chemical properties, and the specific affinity of some metals for some solid phases.Metal distribution in the different phases was found to depend on each land use. Pb found to mainly reside in the residual phase from natural area; while Pb was mainly bound to Fe and Mn oxides in industrial dust. In dust from the urban and industrial sites Cu was equally distributed over Fe and Mn oxides and the residual phase, while in highway dust it mainly resided in the organic fraction. Zn mainly resided in the residual phase in dust from the urban and natural site, while in dust from the suburban site a large proportion of Zn was bound to Fe and Mn oxides. Cd was mainly associated to Fe and Mn oxides in dust from the urban site.Zn was the most mobile metal; Cu was the least mobile metal, while Cd and Pb showed medium risks of being mobilized.

Impact of overland traffic on heavy metal levels in highway dust and soils of Istanbul, Turkey

The purpose of this study was to investigate the impact of overland traffic on the spatial distribution of heavy metals in urban soils (Istanbul, Turkey). Road dust, surface, and subsurface soil samples were collected from a total of 41 locations along highways with dense traffic and secondary roads with lower traffic and analyzed for lead (Pb), zinc (Zn), and copper (Cu) concentrations. Statistical evaluation of the heavy metal concentrations observed along highways and along the secondary roads showed that the data were bimodally distributed. The maximum observed Pb, Zn, and Cu concentrations were 1,573, 522 and 136 mg/kg, respectively, in surface soils along highways and 99.3, 156, and 38.1 mg/kg along secondary roads. Correlation analysis of the metal concentrations in road dust, surface and 20-cm depth soils suggests the presence of a common pollution source. However, metal concentrations in the deeper soils were substantially lower than those observed at the surface, indicating low mobility of heavy metals, especially for Pb and Zn. A modified kriging approach that honors the bimodality of the data was used to estimate the spatial distribution of the surface concentrations of metals, and to identify hotspots. Results indicate that despite the presence of some industrial zones within the study area, traffic is the main heavy metal pollution source.

Source apportionment of PAHs in dated sediments from the Black River, Ohio

Black River, OH, is contaminated with polycyclic aromatic hydrocarbons (PAHs) from coke ovens of a US Steel Corp. Plant. Closing of a coking plant in 1983 and environmental dredging of the sediments during 1989 and 1990 has reduced the PAH levels significantly. This study quantifies the decrease, and consider source apportionment of PAHs in Black River sediments using chemical mass balance modeling. Five vibra cores collected in 1998 and dated using 210Pb and 137Cs, were analyzed for 18 PAHs. The cores had total PAH concentrations between 250 and 0.10 ppm. PAH maxima occur in 1949, 1969, in accordance with regional historical inputs (core BR4), and in 1991 due to remediation (BR6). Coke oven emissions (CO), highway dust (HWY), and wood burning (WB) are likely sources. The CO source (6–92% of total PAHs) is maximal in 1954, and again in 1992–1994 due to the exposure and redistribution of older contaminated sediments during dredging, and decreases thereafter. There is minimal CO content in 1985 (BR4), 2 yr after closure of the coking plant. The HWY contribution (2–86%) is high during 1969–1988, and increases again after 1993. The WB source is less than 23%, and exhibits a minimum (2%) around 1979 (BR4). There is evidence of aerobic biodegradation or photolysis in the sediment of phenanthrene (PhA) at PhA concentrations >500 ppb.

PAHs in dated sediments of Ashtabula River, Ohio, USA.

Polycyclic aromatic hydrocarbons (PAHs) in dated sediments from Ashtabula River, Ohio, were determined, and a chemical mass balance (CMB) model was used to apportion sources. Three cores (AR-1,AR-2,AR-3) were dated by correlating uranium-supported 210Pb peaks with 1964, 1972, 1977, and 1979 maxima in the discharge record for Ashtabula River. These cores had sedimentation rates between 7.1 and 4.4 cm/year, while a fourth (AR-4) exhibited a much higher rate of 27.8 +/- 18 cm/year. The highest PAH concentration was 11,500 ng/g found in layer 6 of AR-1 (1986), and the lowest was 621 ng/g found in layer 8 of AR-2 (1982). The source contributions to the total PAH concentrations estimated by the CMB model are 0.1-2.2%, 16.8-22.8%, and 78.1-83.8% for wood burning (WB), coke oven (CO), and highway dust (HWY), respectively. Petroleum generated PAHs have maximal contribution during 1977-79, and wood burning PAHs show minimal emissions during 1975-77 in accordance with U.S. consumption records and other studies. Among six PAH markers, only phenanthrene may be subjected to aerobic biodegradation or photolysis with an apparent half-life of 0.005-0.025 year. No anaerobic degradation was observed based on the CMB model. The model works well for the nonmarker compounds, fluoranthene, and benzo[b]fluoranthene/benzo[k]fluoranthene.

Apportionment of polycyclic aromatic hydrocarbon sources in lower Fox River, USA, sediments by a chemical mass balance model

AbstractFour sediment cores were collected from the lower Fox River, Wisconsin, USA, to identify possible sources of polycyclic aromatic hydrocarbons (PAHs) using a chemical mass balance model. The cores, which were obtained in 1995 from areas close to Green Bay, Wisconsin, USA, had total PAH concentrations between 19.3 and 0.34 ppm. To determine historical trends of PAH inputs, 210Pb and 137Cs dating was used, and elemental carbon particle analysis was done to characterize particles from the combustion of coal, wood, and petroleum. Source fingerprints were taken from the literature. Our results indicate that coke oven emissions, highway dust, coal gasification, and wood burning are likely sources of PAHs in the lower Fox River. Coke oven emissions are in the range of 40 to 90% of total PAHs, and this fraction decreases from 1930 to 1990, except in core Fox River–A (FR‐A). The overall highway dust (HWY) contribution is between 10 and 75%, and this fraction increases from 1930 to present, except in core FR‐A. The wood burning (WB) contribution (i.e., wood burning or coal gasification) is less than 7% in cores FR‐B, FR‐C, and FR‐D. In core FR‐A, a maximum (≈23%) is found around 1960. The contribution of wood burning has changed from less than 6% in 1950 to between 3 and 10% in 1995. Evidence of aerobic biodegradation or photolysis in the sediment of phenanthrene, with a half‐life of approximately 0.5 years has been found at the site of core FR‐D, which is the shallowest (1.1 m) of the four core sites.

PAHs in Sediments: Unmixing and CMB Modeling of Sources

A chemical mass balance (CMB) model, applied to polycyclic aromatic hydrocarbon (PAH) compounds, is used to apportion PAH sources in a group of seven sediment cores in the Milwaukee Basin of the central Lake Michigan area. PAH apportionment results indicate the dominance of coke oven emissions from 1925–1976, and of highway inputs from 1983–1992 for most of the seven cores. This is consistent with results of carbon particle analysis from the same basin. Milwaukee and Port Washington appear to be primary contributors of point source inputs of PAHs from coke ovens and highway dust. Wood burning is a minor source (<13%). These findings are supported by an independent factor analysis study. Historical PAH records are also determined for the seven sediment cores. The records are unmixed and averaged over the basin. The resulting average record is then used as measured profile in a CMB model to determine PAH sources. Source profiles are historical records of the consumption of coal, petroleum, and wood, including coal used for coke production. A cubic spline technique is developed and applied for the curve fitting of original data points for all of the cores. Unmixed profiles reveal a number of features that are not seen in the original data. Wood burning, coke oven emissions, and highway dust profiles are found to resemble the national consumption records. Coal burning is a very small PAH source (<1%).

Determination of PAH sources in dated sediments from Green Bay, Wisconsin, by a chemical mass balance model

Six sediment cores were collected from Green Bay, Wisconsin, in order to identify possible sources of polycyclic aromatic hydrocarbons (PAHs) by a chemical mass balance (CMB) model. The cores which were obtained in 1995 had total PAH concentrations between 8.04 and 0.460 ppm. 210Pb and 137Cs dating was used to determine historical trends of PAH inputs, and elemental carbon particle analysis was done to characterize particles from combustion of coal, wood and petroleum. The results show that coke burning, highway dust, and wood burning are likely sources of PAHs to Green Bay. The contribution of coke oven emissions (CB) for the Green Bay cores is in the range of 5 to 90%. The overall highway dust (HWY) contribution is between 5 and 70%. There is a maximum (∼67%) contribution of HWY around 1988 which is in agreement with the historical US petroleum consumption. The wood burning (WB) contribution is between 1 to 30%, except in core GB-A where a maximum (∼50%) is found around 1994. The average relative errors of measurement for x 2 equal to the number of degrees of freedom, are 52.5, 56.2, 36.2, 52.3, and 42.8 (df = 3) for the Green Bay cores A, B, C, E, and F, respectively. The sums of the contribution factors are less than one, indicating gain of inert biological or other bulk material between source and receptor. The results of carbon particles for Green Bay core D show that coal, oil, and wood burning are consistent with the CMB modeling results.

Sources of Polycyclic Aromatic Hydrocarbons in Sediments of the Kinnickinnic River, Wisconsin

A chemical mass balance (CMB) model was developed and used to apportion both point and nonpoint sources of polycyclic aromatic hydrocarbons (PAHs) in six dated sediment cores. The cores were collected in 1994 from a stretch of the Kinnickinnic River between the Becher Street Bridge and the Wisconsin Wrecking Company Wharf, Milwaukee, Wisconsin, and had PAH concentrations of 80 to 1,000 ppm. This work was done in order to identify major PAH sources to this IJC Area of Concern which is important for pollution modeling and management. The source fingerprints were taken from the literature. Coke oven emissions and coal-wood gasification or coal tar are the main local PAH sources, whereas highway dust provides an important nonpoint input since the 1920s. Coal-wood gasification ceases to be a significant source after 1950–’60. Factor analysis based on nonnegative constraint of factor scores and loadings, and oblique rotations, supports this apportionment, but points also to deficiencies in the CMB source profile for coke oven emissions. It appears that the now defunct Milwaukee Solvay Coke Co. was a major source. The influence of geophysical factors and chemical and biological fractionation of the selected PAH compounds appears to be small.

A Source-Receptor Method for Determining Non-Point Sources of PAHs to the Milwaukee Harbor Estuary

The purpose of this work is to determine non-point sources of PAHs to the Milwaukee Harbor Estuary. Sediment samples were collected from the Milwaukee River, the Menomonee River, the Kinnickinnic River, and the Inner and Outer Harbor of the Milwaukee Harbor Estuary. Source samples were collected from a major highway, a leaking underground storage tank, and two river banks. All samples were analyzed for sixteen PAHs, which are identified as priority pollutants by the U.S. EPA. In addition to this, literature values of concentrations of PAHs in known non-point sources viz. coal tar, coal tar air emissions, No. 2 fuel oil, and gasoline engine exhaust tar were considered. A computer program, using the mathematics of least-squares, was adopted to determine the best combination of sources to the mixed PAH signature of the sediment, and to calculate the contribution of each source to the concentration of total PAHs. Chi square and the multiple correlation coefficient were used to evaluate the fits. For apportionment of sediment PAHs into sources, only those PAHs are considered whose concentrations are above the instrument's (GC-MS) detection limit. Of the 211 regressions considered, about half present good fits to the proposed sources. Highway dust is found to be a significant source in 88%, gasoline engine exhaust tar in 33%, coal tar air emissions in 23%, and coal tar in 17% of the successful regressions.