Extensive Green Roofs as a Means to Capture Polycyclic Aromatic Hydrocarbons (original) (raw)
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Sources of Polycyclic Aromatic Hydrocarbons in Urban Storm Water runoff in Tijuana, Mexico
Eight sites were sampled during seven rain events to quantify and identify the sources of polycyclic aromatic hydrocarbons in urban runoff in the city of Tijuana, Mexico. The total Σ16 PAHs concentration rangedfrom 1113 to 4866 µg/Lin the sampled sites and thetotal suspended solid concentrations ranged from 7725 to 4413 µg/L. The high concentrations of total suspended solids were probably the result of the erosion of bare soil areas in the basin area of the sampling sites. The PAH concentration in urban runoff from industrial sites was not as high as expected in comparison to residential sites. The potential sources of PAH were identified using the diagnostic ratios between PAHs and PCA analysis. Vehicular exhaust emissions (diesel and gasoline) and used crankcase oil were the main contributors to PAHs in urban storm water runoff. Charcoal combustion, diesel oil andlubricant oil were also identified as contributors to PAHs.
Water science and technology : a journal of the International Association on Water Pollution Research, 2011
The concentrations of polycyclic aromatic hydrocarbons (PAHs) in water and sediments of seven wet detention ponds receiving urban stormwater were investigated. The ponds comprised traditional wet detention ponds with a permanent wet volume and a storage volume as well as ponds that were expanded with sand filters and other means to improve the removal of micropollutants. The concentrations of ∑PAH in the sediments varied between 6 ± 5 and 2,222 ± 603 ng g À1 dry weight (mean ± standard deviation), and were highest in the ponds with lower pond volume per catchment area and did not clearly reflect different activities in the catchments. In general, the concentrations of PAHs in the sediments decreased from inlet to outlet, especially in the systems with good conditions for sedimentation such as systems with flow perpendicular sand dikes and extensive submerged vegetation. High molecular weight PAHs were predominant in the sediments indicating the pyrogenic origin of the PAHs. There was no correlation between PAH species concentrations in water or sediments and their hydrophobicity (log K ow ). PAH concentrations in water fluctuated in response to intensity and frequency of rain events, whereas concentrations in the sediments integrated the pollutant load over time. Pond systems expanded with sand filters and other technologies to enhance removal of micropollutants consistently had concentrations of PAHs in the effluents below the detection level.
Polycyclic aromatic hydrocarbons in harvested rainwater in Warri and Agbarho, Nigeria
Bulletin of The Chemical Society of Ethiopia, 2022
The aim of this research was to provide an overview of current knowledge, by assessing the possible contamination sources of harvested rainwater by polycyclic aromatic hydrocarbons (PAHs), its effects and possible human health risk assessment. Random sampling technique was used to collect eight rainwater samples from different roofing materials made from (asbestos, zinc, aluminium and thatch) in Warri and Agbarho (AGB). The samples were extracted using a liquid-liquid extraction (LLE) system according to the established procedures of United States Environmental Public Agency (USEPA). Under the optimized conditions, the ranges of extraction recoveries and solid-phase extraction (SPE) clean-up of the PAHs in the harvested rainwater were in the range of 71-90%. Gas chromatography-mass spectrometry (GC-MS) was used for the determination of the sixteen priority PAHs in the samples. The total concentration of PAHs for each of the roof types in Warri Refinery Petrochemical Company (WRPC) are: 0.036±0.012, 0.047±0.020, 0.045±0.018 and 0.0023±0.008 ppm for aluminium, zinc, asbestos and thatch roof, respectively. In addition, total concentration of PAHs for each of the roof types in AGB are: 0.046±0.020, 0.024±0.009, 0.023±0.008 and 0.021±0.007 ppm for aluminium, zinc, asbestos and thatch roof. The PAHs analysed exceeded the United States environmental protection agency (USEPA) standards of contamination.
POLYCYCLIC AROMATIC HYDROCARBONS IN URBAN SOILS OF KEMAMAN
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous organic pollutants in urban environments and are considered as the priority pollutants by the U.S. Environmental Protection Agency. The objective of this study was to determine the depth-wise distribution (0-15, 15-30, and 30-45 cm) of 16 PAHs compounds in four urban soils of different land uses (residential, public parks, public buildings, and commercial areas) in Miami, Florida, USA. The PAHs were analyzed using a Gas Chromatograph equipped with a Flame Ionization Detector. Results showed that across use soils, total PAHs were significantly greater at surface (1,869 µg/kg) than sub-surface (478-1,079 µg/kg). Among land uses at 0-15 cm, PAHs were significantly greater in commercial areas (2,364 µg/kg) than the residential and public parks (1,508-1,595 µg/kg), but not the public buildings (2,007 µg/kg). However, at lower depths, PAHs were greater in residential soils (15-30 cm: 1,454 µg/kg; 30-45 cm: 834 µg/kg) compared with other land uses (15-30 cm: 839-1,104 µg/kg; 30-45 cm: 251-456 µg/kg). The contents of high molecular weight PAHs (HMW PAHs ) were greater than the low molecular weight PAHs (LMW PAHs ) in all soils at all depths. For example, at 0-15 cm, HMW PAHs were twice as much (1,039-1,602 µg/kg) as LMW PAHs (467-762 µg/kg). All three source identification indices, including the predominance of HMW PAHs over the LMW PAHs , 0.42 to 0.50 ratio of fluoranthene to fluoranthene + pyrene, and 0.78 to 1.36 ratio of phenanthrene to anthracene, suggest that the dominant source of PAHs in the urban soils originated from the pyrogenic processes, particularly the burning of fossil fuel. These results can help set baseline concentrations and the exposure risk to terrestrial organisms of PAHs in the urbanized and rapidly urbanizing areas.
Air Quality, Atmosphere & Health, 2014
This study reported the distribution of polycyclic aromatic hydrocarbons (PAHs) concentrations simultaneously obtained in gas/rain/particle in rain event from 2010 to 2012 in Osaka, Japan. A sampling method for rain and the materials of a rain collector were also surveyed. Benzene and a glass bottle were used to prevent the decrease of PAHs in rainwater. The average concentration of Σ9PAHs in rainwater ranged between 17.49 and 646.52 ng dm −3. The mean ratio of these Σ9PAHs in gas versus particles was 77.9 and 68.3 % during rain and no rain, respectively. During rain, the PAHs in particles were scavenged by rain and were incorporated via washout by collision with each other. Therefore, the ratio of PAHs in rainwater was similar to that in particles. The low molecular weight LMW-PAHs from gas were recognized as being dissolved in rain but did not affect the ratio of PAHs in rain. Four rings PAH were dominant in gas/rain/particles. The seasonal variation of Σ9PAHs in rainwater was reported and discussed, and the PAHs levels during the winter and spring were higher compared with that of summer and autumn. Furthermore, the sampling method of PAHs in snow is also developed.
Estuaries, 2002
Urban and suburban storm water runoff from ten locations in eastern Massachusetts was analyzed for 39 polycyclic aromatic hydrocarbons (PAHs) compounds. Similar profiles in PAH composition were observed for groups of samples and appear to reflect land use. The largest group includes urban storm water from areas with a mix of industrial, commercial, and residential use. Fluoranthene, phenanthrene, pyrene, chrysene, and benzo(b)fluoranthene were the predominant compounds in this group, but lighter molecular weight PAHs were also present. Sources of PAHs to storm water include a combination of petroleum and combustion. The profile of PAH compounds in local atmospheric deposition was similar to urban storm water, but differed in several of the predominant compounds. PAHs in storm water could increase the levels of these compounds in nearshore sediments and may be the most important source of high molecular weight PAHs to these environments.
Journal of Geoscience and Environment Protection
Polycyclic aromatic hydrocarbons (PAHs) are by-products arising from incomplete combustion. These organic chemicals substances are found almost everywhere and pose a risk to human health because of their potentially hazardous nature and bioavailability in the environment as determined by several regulatory agencies such as US Environmental Protection Agency (US-EPA), US Department of Health and Human Services (DHHS), International Agency for Research on Cancer (IARC) and the National Agency for Food and Drug Administration and Control (NAFDAC). The paper is aimed at studying polycyclic aromatic hydrocarbons in water. The possible sources, chemistry, risk and remediation strategies for polycyclic aromatic hydrocarbons in water have been considered. Studies have shown that exposure to PAHs at levels above the maximum contaminant level for relatively short periods will cause damage to the red blood cells leading to anaemia; suppressed immune system. Long-term exposure to Benzo(a)pyrene at levels above the maximum contaminant level has the potential to cause developmental and reproductive defects as well as cancer. US-EPA, IARC and DHHS has sets a maximum contaminant level (MCL) for benzo(a)pyrene, the most carcinogenic PAH, at 0.0002 mg/L, 0.0001 mg/L for benz(a)anthracene, 0.0002 mg/L for benzo(b)fluoranthene, benzo(k)fluoranthene, and chrysene. 0.0003 mg/L and 0.0004 mg/L have been set for dibenz(a,h)anthracene and indeno (1,2,3c,d)pyrene respectively. Sustained barn on smoking in public places and burning of word, use of concretes in road construction as against the traditional surfacing of roads using coal tar as well as cars running on compressed natural gas (CNG) or liquefied petroleum gas (LPG) can form part of the preventive strategies.
Occurrence and distribution of PAHs in rainwater and urban runoff
2007
Polycyclic aromatic hydrocarbons (PAHs) have received considerable attention in scientific communities during the past few decades because of their ubiquitous presences and carcinogenic properties. PAHs are formed mainly by thermal decomposition of organic compounds consisting of hydrogen and carbon. PAHs are introduced into the environment by natural and anthropogenic sources. Natural sources (e.g. forest fires and volcanoes) are minor contributors in comparison to the anthropogenic sources (e.g. emissions from vehicles, power plants, incinerators, petroleum refineries). In order to fully comprehend the occurrence and distribution of PAHs in Singapore's water systems, the composition of PAHs in rainwater and stormwater were studied in detail. While wet deposition is a main route by which PAHs are removed from the atmosphere, urban
Atmospheric Environment, 2006
A year-long sampling and analysis of 24 h airborne particles equal to or less than 10 mm (PM 10 ) was conducted in Southwest (SW) Mexico City in 1998. The amount of airborne PM 10 and its extractable organic matter (EOM) were highly correlated. The year 1998 was particularly dry with many fires, and higher values of PM 10 and EOM were obtained in the fire period (February-May) compared to the without fire period (January, June-December). The indirect-acting mutagenicity (Salmonella typhimurium strain TA98 with mammalian metabolic activation, S9) did not correlate with the monthly concentrations of PM 10 and EOM, while the direct-acting mutagenicity (strains TA98 and YG1021, without mammalian metabolic activation) did correlate. The highest monthly mutagenic potency of TA98+S9 and of TA98ÀS9 were registered in May which correspond to the fire period, while for YG1021 the highest was in December, a without fire month. The highest TA98+S9/TA98ÀS9 ratios appeared from April to September (with the exception of June), indicating that emission of the direct mutagens occurred in the rest of the year (the coldest months), and December showed the highest mutagenicity of YG1021. The correlation of this mutagenicity with the number of ground-based inversions indicated a greater emissions of nitroarenes in the coldest months emitted mainly by vehicular traffic as shown by the correlation between YG1021 with CO and with NO 2 . We did not find a correlation in the EOM of the complex mixtures between TA98+S9 and the total concentration of polycyclic aromatic hydrocarbons (PAH) nor between TA98+S9 and specific PAH. The analysis by gas chromatography/mass spectrometry indicated the presence of retene, a PAH found in the fire period and considered a softwood burning marker. The concentrations of fluoranthene and benz[a]anthracene correlated with that of retene and with the burned area; they were the only PAH that presented significant differences between the periods with fire and without fire, showing that these compounds could have a similar origin. Benzo[ghi]perylene, coronene and indeno[1,2,3-cd]pyrene were the most abundant PAH of the 17 analyzed in SW Mexico City, indicating that the main emission source for PAH in the airborne particle phase in this zone were vehicles with the combustion of gasoline and diesel rather than wood burning. The mean concentrations for most PAH were higher during the fire period, except for perylene and coronene, suggesting that the fires were not the emission source for these two last PAH.
WATERSHED-BASED SOURCES OF POLYCYCLIC AROMATIC HYDROCARBONS IN URBAN STORM WATER
Environmental Toxicology and Chemistry, 2006
Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic and mutagenic compounds, ubiquitous in the air and water of urban environments, and have been shown to accumulate in coastal estuarine and marine sediments. Although previous studies have documented concentrations and loads of PAHs in urban runoff, little is known about the sources and temporal patterns of PAH loading from storm water. This study characterized the sources and temporal patterns of PAHs in urban storm water by analyzing PAH concentrations and loads from a range of homogeneous land use sites and in-river mass emission sites throughout the greater Los Angeles, California, USA, region. Samples were collected at 30-to 60-min intervals over the course of a storm during multiple storm events over a four-year period in order to investigate PAH sources and inter-and intrastorm patterns in loading. Polycyclic aromatic hydrocarbon storm fluxes ranged from 1.3 g/km 2 for the largely undeveloped Arroyo Sequit watershed to 223.7 g/km 2 for the highly urbanized Verdugo Wash watershed, with average storm fluxes being 46 times higher in developed versus undeveloped watersheds. Early-season storms repeatedly produced substantially higher loads than comparably sized lateseason storms. Within individual storms, PAHs exhibited a moderate first flush with between 30 and 60% of the total PAH load being discharged in the first 20% of the storm volume. The relative distribution of individual PAHs demonstrated a consistent predominance of high-molecular-weight compounds indicative of pyrogenic sources.