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1.
Waste plastic (WP) and tall oil pitch (T), which are organic recycled industrial by-products, have been used as a binder with bitumen in stone mastic asphalt (SMA) and asphalt concrete (AC). We compared the exposure over one workday in 16 road pavers participating in a survey at four paving sites, using mixes of conventional asphalt (SMA, AC) or mixes containing waste material (SMA-WPT, AC-WPT). The concentrations of 11 aldehydes in air were 515 and 902 microg m(-3) at the SMA-WPT and AC-WPT worksites, being 3 and 13 times greater than at the corresponding worksites laying conventional asphalt. Resin acids (2-42 microg m(-3)), which are known sensitizers, were detected only during laying of AC-WPT. The emission levels (microg m(-3)) of total particulates (300-500), bitumen fumes (60-160), bitumen vapour (80-1120), naphthalene (0.59-1.2), phenanthrene (0.21-0.32), pyrene (<0.015-0.20), benzo(a)pyrene (<0.01) and the sum of 16 PAHs (polycyclic aromatic hydrocarbons, 1.28-2.00) were similar for conventional and WPT asphalts. The dermal deposition of 16 PAHs on exposure pads (on workers' wrist) was low in all pavers (0.7-3.5 ng cm(-2)). Eight OH-PAH biomarkers of naphthalene, phenanthrene and pyrene exposures were quantified in pre- and post-shift urine specimens. The post-shift concentrations (mean +/- SD, micromol mol(-1) creatinine) of 1- plus 2-naphthol; 1-,2-,3-,4- plus 9-phenanthrol; and 1-hydroxypyrene were, respectively, for asphalt workers: 18.1+/- 8.0, 2.41 +/- 0.71 and 0.66+/- 0.58 (smokers); 6.0+/- 2.3, 1.70+/- 0.72 and 0.27+/- 0.15 (non-smokers); WPT asphalt workers: 22.0+/- 9.2, 2.82+/- 1.11 and 0.76+/- 0.18 (smokers); 6.8+/- 2.6, 2.35+/- 0.69 and 0.46+/- 0.13 (non-smokers). The work-related uptake of PAHs was low in all pavers, although it was significantly greater in smokers than in non-smokers. The WPT asphalt workers complained of eye irritation and sore throat more than the pavers who had a much lower exposure to aldehydes and resin acids.  相似文献   

2.
The present study aimed to assess whether urinary germanium concentration can be used as a biomarker of inhalation exposure to airborne dust from metallic germanium (Ge) or GeO2 in the occupational setting. A novel hydride generation-based method coupled with fow-injection graphite furnace atomic absorption spectrometry (HG/FI-GFAAS) was developed for the determination of urinary germanium. It was found that urinary germanium concentration could be reliably determined by a standard additions method after thorough digestion of the urine and careful pH adjustment of the digest. The limit of detection (LOD) in urine for the HG/FI-GFAAS method was 0.25 microg Ge L(-1). In Belgian control male subjects, the urinary germanium concentration was below this LOD. In 75 workers currently exposed to inorganic germanium compounds, respirable and inhalable concentrations of germanium in the aerosols were measured on Monday and Friday at the job sites using personal air samplers. Spot-urine samples were collected on the same days before and after the work shift. The germanium concentrations of respirable dust correlated very well with those of inhalable dust and represented 20% of the inhalable fraction. Workers exposed to metallic Ge dust were on average ten times less exposed to germanium than those whose exposure involved GeO2 (3.4 versus 33.8 microg Ge m(-3)). This difference was reflected in the urinary germanium concentrations (3.4 versus 23.4 microg Ge g(-1) creatinine). Regression analysis showed that the concentration of germanium in the inhalable fraction explained 42% of the post-shift urinary germanium concentration either on Monday or on Friday, whereas in a subgroup of 52 workers mainly exposed to metallic germanium dust 57% (r = 0.76) of the Monday post-shift urinary germanium was explained. Urinary elimination kinetics were studied in seven workers exposed to airborne dust of either metallic Ge or GeO2. The urinary elimination rate of germanium was characterised by half-times ranging from 8.2 to 18.1 h (on average 12 h 46 min). The present study did not allow discrimination between the germanium species to which the workers were exposed, but it showed fast urinary elimination kinetics for inhalation exposure to dust of metallic Ge and GeO2. It pointed out that urine samples taken at the end of the work shift can be used for biological monitoring of inorganic germanium exposure in the occupational setting.  相似文献   

3.
Exposure to diesel exhaust was evaluated in summer and winter by measuring vapour and particle phase polycyclic aromatic hydrocarbons (PAHs). Fifteen PAHs were simultaneously determined from the air samples obtained from truck drivers collecting household waste and maintenance personnel at a waste handling centre. The major compounds analysed from the personal air samples of exposed workers were naphthalene, phenanthrene and fluorene. The total PAH exposure (sum of 15 PAHs) of garbage truck drivers ranged from 71 to 2,660 ng m(-3) and from 68 to 900 ng m-3 in the maintenance work. The exposure of garbage truck drivers to benzo[a]pyrene (B[a]P) ranged from the mean of 0.03 to 0.3 ng m(-3) whereas no B[a]P in control samples or in those collected from maintenance workers was detected. A statistically significant difference in diesel-derived PAH exposure between the garbage truck drivers and the control group in both seasons (in summer p = 0.0022, degrees of freedom (df) 70.5; and in winter p < 0.0001, df = 80.4) was observed. Also, a significant difference in PAH exposure between the garbage truck drivers and the maintenance workers (in summer p < 0.0001, df = 50.1; and in winter p < 0.0001, df = 44.2) was obtained.  相似文献   

4.
To study whether the urinary 1-hydroxypyrene (1-OHP) could be the biomarker of atmospheric PAHs, a small-scale pilot study was carried out on the relation of 1-OHP vs PAHs with the traffic policemen in Beijing of smokers and nonsmokers to be subgroups in both the exposure and control groups. Both the PAHs and 1-OHP were analyzed with high performance liquid chromatography (HPLC). The ambient concentrations of PAHs were different at the different sites (the average sum of PAHs (TPAH) were 12.36, 16.27, 18.37 ng/m3 at the suburban residential, police station and high traffic area, respectively.), but considerably lower than the personal-exposure concentrations (the average TPAH were 65.84 and 47.28 ng/m3 for patrol cars and inspection station, respectively). Pyrene was correlated well with BaP and the summed PAHs (TPAH), with the correlation coefficients (R) of 0.79, 0.87 for ambient level and 0.92, 0.96 for personal exposure, respectively. The average of 1-hydroxypyrene of smokers and nonsmokers were 0.39, 0.15 μmol/mol creatinine in control group and 0.57, 0.33 μmol/mol creatinine in exposure group, respectively. The better correlation of pyrene to BaP and TPAH especially for personal exposure samples indicated that the probability of urinary 1-hydroxypyrene, the metabolite of pyrene, to be the biomarker of total PAH. Nonsmokers in the exposure and control groups had indistinguishable levels of 1-OHP, presumably because the ambient levels of pyrene were so similar (the average were 3.25, 3.20 ng/m3 at the police station and high traffic area, respectively.). Smokers in the control group had significantly higher 1-OHP than that of the nonsmokers, but showed indistinguishable differences in the exposure group. These results suggested that urinary 1-OHP could be a biomarker of PAHs only when the level of PAHs was at a relatively higher level. Smoking as an important influencing factor need to be controlled carefully.  相似文献   

5.
Polycyclic aromatic hydrocarbons (PAH) include compounds with two or more fused benzene rings, many of which are carcinogens. Industrial sources produce hundreds of PAH, notably in the coke- and aluminium-producing industries. Because PAH are distributed at varying levels between gaseous and particulate phases, exposure assessment has been problematic. Here, we recommend that occupational exposures to naphthalene be considered as a potential surrogate for occupational PAH exposure for three reasons. Naphthalene is usually the most abundant PAH in a given workplace; naphthalene is present almost entirely in the gaseous phase and is, therefore, easily measured; and naphthalene offers several useful biomarkers, including the urinary metabolites 1- and 2-hydroxynaphthalene. These biomarkers can be used to evaluate total-body exposure to PAH, in much the same way that 1-hydroxypyrene has been applied. Using data from published sources, we show that log-transformed airborne levels of naphthalene are highly correlated with those of total PAH (minus naphthalene) in several industries (creosote impregnation: Pearson r= 0.815, coke production: r= 0.917, iron foundry: r= 0.854, aluminium production: r= 0.933). Furthermore, the slopes of the log-log regressions are close to one indicating that naphthalene levels are proportional to those of total PAH in those industries. We also demonstrate that log-transformed urinary levels of the hydroxynaphthalenes are highly correlated with those of 1-hydroxypyrene among coke oven workers and controls (r= 0.857 and 0.876), again with slopes of log-log regressions close to one. These results support the conjecture that naphthalene is a useful metric for occupational PAH exposure. Since naphthalene has also been shown to be a respiratory carcinogen in several animal studies, it is also argued that naphthalene exposures should be monitored per se in industries with high levels of PAH.  相似文献   

6.
Non-occupational inhalation and ingestion exposure to polycyclic aromatic hydrocarbons (PAHs) has been studied in 8 non-smoking volunteers through personal air sampling and urinary biomonitoring. The study period was divided into 4 segments (2 days/segment), including weekdays with regular commute and weekends with limited traffic related exposures; each segment had a high or low PAH diet. Personal air samples were collected continuously from the subjects while at home, at work, and while commuting to and from work. All urine excretions were collected as individual samples during the study. In personal air samples, 28 PAHs were measured, and in urine samples 9 mono-hydroxylated metabolites (OH-PAHs) from 4 parent PAHs (naphthalene, fluorene, phenanthrene and pyrene) were measured. Naphthalene was found at higher concentrations in air samples collected at the subjects' residences, whereas PAHs with four or more aromatic rings were found at higher levels in samples taken while commuting. Urinary OH-PAH biomarker levels increased following reported high inhalation and/or dietary exposure. On days with a low PAH diet, the total amount of inhaled naphthalene during each 24-hour period was well correlated with the amount of excreted naphthols, as was, to a lesser extent, fluorene with its urinary metabolites. During days with a high dietary intake, only naphthalene was significantly correlated with its excreted metabolite. These findings suggest that this group of non-occupational subjects were exposed to naphthalene primarily through indoor air inhalation, and exposed to other PAHs such as pyrene mainly through ingestion.  相似文献   

7.
The aims were to assess the impact of a total smoking ban on the level of airborne contaminants and the urinary cotinine levels in the employees in bars and restaurants. In a follow up design, 13 bars and restaurants were visited before and after the implementation of a smoking ban. Ninety-three employees in the establishments were initially included into the study. The arithmetic mean concentration of nicotine and total dust declined from 28.3 microg m(-3) (range, 0.4-88.0) and 262 microg m(-3) (range, 52-662), respectively, to 0.6 microg m(-3) (range, not detected-3.7) and 77 microg m(-3) (range, not detected-261) after the smoking ban. The Pearson correlation coefficient between airborne nicotine and total dust was 0.86 (p < 0.001; n = 48). The post-shift geometric mean urinary cotinine concentration declined from 9.5 microg g(-1) creatinine (cr) (95% CI 6.5-13.7) to 1.4 microg g(-1) cr (95% CI 0.8-2.5) after the ban (p < 0.001) in 25 non-snuffing non-smokers. A reduction from 1444 microg g(-1) cr (95% CI 957-2180) to 688 microg g(-1) cr (95% CI 324-1458) was found (p < 0.05) in 29 non-snuffing smokers. The urinary cotinine levels increased from 11.7 microg g(-1) cr (95% CI 7.0-19.6) post-shift to 21.9 microg g(-1) cr (95% CI 13.3-36.3) (p < 0.01) in the next morning in 24 non-snuffing non-smokers before the smoking ban. A substantial reduction of airborne nicotine and total dust was observed after the introduction of a smoking ban in bars and restaurants. The urinary cotinine levels were reduced in non-smokers. The decline found in smokers may suggest a reduction in the amount of smoking after intervention. In non-smokers cotinine concentrations were higher based on urine sampled the morning after a shift than based on urine sampled immediately post-shift.  相似文献   

8.
Airborne particulate matter was collected and biomonitoring of workers was performed by sampling blood, urine and hair of 84 exposed subjects, 17 occasionally exposed employees, 21 controls from administrative offices and 25 unexposed people (external controls). Determination of Pd was performed using Quadrupole and High Resolution Inductively Coupled Plasma Mass Spectrometry. The Production of Catalysts Department and the Refining Service presented the highest levels of Pd in airborne matter collected by means of an area sampler. The highest level of soluble Pd (1.66 microg m(-3)) was found in the Production of Catalysts Department. The highest concentration of Pd in airborne matter, collected by means of personal devices (7.90 microg m(-3)) was found in the Refining Service. Hair showed a clear distribution pattern among departments, with values ranging from 0.60 to 5.54 microg g(-1). Administrative workers presented blood levels of Pd between 2 and 500 times higher than external controls. Only urine levels correlated with the measurements of airborne Pd collected with personal devices. A very strong association between airborne Pd collected by personal devices and Pd levels in hair (r(2)= 0.569, with p< or = 0.01) and urine (r(2)= 0.684, with p< or = 0.01) was found. On the basis of these findings: (i) blood results appear to be an unsuitable biological marker for occupational exposure to Pd; (ii) urine could be considered as a satisfactorily responsive bio-marker for occupational monitoring; and (iii) hair cannot be considered a good index of time-related exposure.  相似文献   

9.
The concentrations of fifteen PAH compounds in samples of sediment and blue mussel tissue (Mytilus trossulus) were measured. In addition, the biliary polycyclic aromatic hydrocarbon metabolites present in flounder (Platichthys flesus) were analysed. Two methods were used in the analysis of PAH metabolites; high performance liquid chromatography (HPLC) and fixed wavelength fluorescence (FF). The major PAH metabolite which could be measured using the HPLC method was 1-OH pyrene. It was possible to detect 1-OH Phe and 3-OH B[a]P in 70 and 24 samples respectively, of the 87 samples analysed. However, the concentrations of 1-OH Phe and 3-OH B[a]P were below or near to the LOQ (0.002 μg ml(-1) bile). The bile of flounder samples from the Gulf of Gdańsk had 1-OH Pyr concentrations which ranged from 0.019 to 0.066 μg ml(-1) bile. The high linear correlation observed between the quantity of 1-OH pyrene determined by the HPLC-F method and the content of the sum of pyrene-type PAHs obtained by the FF method indicated the FF method of determination of pyrene-type PAH metabolites can be used as a screening method. The content of ∑(15)PAHs in sediments collected in the Gulf of Gdansk, in 2008, ranged from 29.3 to 103 μg kg(-1) dw. In mussel tissue ∑(15)PAHs concentrations were between 173.2 μg kg(-1) dw and 237.7 μg kg(-1) dw. All concentrations measured in the current study, in mussel tissue, were below the OSPAR toxicity threshold values.  相似文献   

10.
A high-performance liquid chromatography (HPLC) method for biomonitoring of occupational wood dust exposure based on nasal lavage as a biomonitoring matrix was developed. Gallic acid (GA) was chosen as the indicator compound for oak dust exposure. From the chromatographic profile of ash dust, four peaks were chosen as indicator compounds. Phenolic indicator compounds were analysed by HPLC. Personal dust samples and corresponding nasal lavage samples were collected from 16 workers exposed to oak dust and six to ash dust. The dust concentrations in the workers' breathing zone varied between 0.7 and 13.8 mg m(-3). The indicators revealed the nature of the wood dust inhaled. For the workers who did not use respirators, the correlation between the dust and corresponding indicator compound in their nasal lavage was significant; r2 = 0.59 (n = 12) for oak dust and r2 = 0.58 (n = 6) for ash dust, respectively. Further, the correlation for oak dust workers who used respirators was r = 0.67 (n = 4). Nasal lavage sampling and HPLC analysis of polyphenol indicator compounds are promising tools for measuring wood dust exposure. Although further validation is necessary, determination of the individual dose may prove invaluable in prospective epidemiological studies.  相似文献   

11.
The aim of this study was to assess the associations between airborne and dustborne microbial contaminants (endotoxin and β-D-glucan) and estimate the effects of home characteristics on exposure levels of these microbial contaminants. Endotoxin and β-D-glucan concentrations in airborne inhalable particles, airborne PM1 (<1 μm) and vacuumed dust from 184 residential homes were determined using specific Limulus amebocyte assays. Home characteristics were recorded by visual inspection and questionnaires. Linear regression and correlation analyses were performed. Inhalable endotoxin correlated with dust endotoxin (r = 0.34, p < 0.001) and PM1 endotoxin (r = 0.33, p < 0.001). Inhalable β-D-glucan correlated with dust β-D-glucan (r = 0.18, p < 0.01), but not with PM1 β-D-glucan. Significant correlation was also found between PM1 and dust concentrations for endotoxin (r = 0.26, p < 0.001), but not for β-D-glucan. Multivariate regression analyses showed only one significant association between airborne contaminants and environmental characteristics: inhalable β-D-glucan was positively associated with relative humidity with an effect size (change in the dependent variable corresponding to a unit increase in the independent variable) of 2.32 and p < 0.05. In contrast, several associations were found between dust concentrations and environmental characteristics. Dust endotoxin was positively associated with temperature (2.87, p < 0.01) and number of inhabitants (2.76, p < 0.01), whereas dust β-D-glucan was inversely associated with the presence of dogs (-2.24, p < 0.05) and carpet (-3.05, p < 0.01) in the home. In conclusion, dustborne contaminants were more strongly affected by home characteristics than airborne contaminants. Furthermore, even though statistically significant, the correlations between airborne and dustborne contaminants were weak. This indicates that airborne concentrations cannot be reliably predicted based on dustborne concentrations.  相似文献   

12.
Ambient gas and particle phase samples were collected during two sampling periods from a residential area of an industrialized city, Kocaeli, Turkey. The sampling occurred during winter months when structures were being heated, and summer months when structures were not being heated. Σ(13)PAH (gas + particle) concentrations ranged between 6.2 ng m(-3) (DahA) and 98.6 ng m(-3) (Phe) in the heating (winter) period and 3.0 ng m(-3) (BaA) and 35.1 ng m(-3) (Phe) in the non-heating (summer) period. Phe, Flt and Pyr were found to be at high concentrations in both sampling periods. Winter time to summer time concentration ratios for individual ambient PAH concentration ratios ranged between 1.2 (DahA) and 17.5 (Flu), indicating the effect of the emissions from residential heating on measured concentrations of PAHs, but great industrial plants and the only incinerator facility of Turkey are other important pollution sources around the city. Temperature dependence of gas phase PAHs was investigated using the Clausius-Clapeyron equation. A high slope obtained (5069.7) indicated the effect of the local sources on measured gas phase PAHs. Correlation of the supercooled vapor pressure (P) with the gas particle partitioning coefficient (K(p)) and particle phase fraction was also evaluated. The relationship between the meteorological parameters and individual PAH (gas + particle) concentrations was investigated further by multiple linear regression analysis. It was found that the temperature had a significant effect on all of the measured PAH concentrations, while the effects of the wind speed and direction were not significant on the individual PAHs. On the other hand, PAH concentrations showed a strong linear relationship with the ventilation coefficient (VC) which showed the influence of local sources on measured PAHs. Benzo[a]pyrene toxic equivalent (BaP(eq.)) concentrations were used for health risk assessment purposes. The winter period risk level (2.92 × 10(-3)) due to the respiratory exposure to PAHs was found to be almost 3 times higher than in the summer period (1.15 × 10(-3)).  相似文献   

13.
The zebra mussel, Dreissena polymorpha, was utilized in an in situ study in the Times Beach Confined Disposal Facility (CDF) located in Buffalo, New York, Mussels, placed both in the water column (upper position) and at the sediment surface (lower position), survived a 34-day exposure to the CDF. At the CDF, total polycyclic aromatic hydrocarbon (PAH) concentrations in the water column were below detection limits (<0.010 mg 1-1), mean total PAH concentrations in the sediment were 164.41 mg kg-1, and mean total PAH concentrations in mussel tissues after the 34-day exposure were 6.58 mg kg-1. PAH concentrations in mussels exposed for 34 days at the CDP were compared to a baseline PAH concentrations in mussel tissue prior to study initiation (Day 0), and mussel tissue from the reference site (Black Rock Channel Lock). There was a significant increase in total PAHs in mussel tissues over the 34 Day period at the CDF. No significant accumulation occurred at the reference site. PAHs which increased significantly in mussel tissue at the CDF were fluoranthene, pyrene, chrysene, and benzo(a)anthracene. Benzo(a)anthracene concentrations increased significantly in mussels at the upper position overall at Times Beach. Concentrations of Total PAHs, fluoranthene, pyrene, and chrysene were not related to position.  相似文献   

14.
分析了隧道沥青摊铺过程环境空气中的TSP及多环芳烃质量浓度。TSP用膜法,中流量采样器采样15 min,重量法分析;超声波萃取,高效液相色法分析多环芳烃。结果表明,摊铺机周围空气中TSP超过8 mg/m3,道路空气中TSP超过3 mg/m3;环境空气中苊烯等12种多环芳烃均有检出,苊烯和艹屈质量浓度较高,苯并[a]芘和二苯并[a,h]蒽质量浓度较低。苯并[a]蒽、苯并[a]芘和二苯并[a,h]蒽超标,对人体健康危害较大。建议加强相关行业PAHs的排放水平及其健康风险研究,制定相关限值标准和沥青摊铺过程环境空气的沥青烟监测方法标准。  相似文献   

15.
Inorganic arsenic is a potent human carcinogen and toxicant which people are exposed to mainly via drinking water and food. The objective of the present study was to assess current exposure to arsenic via drinking water in three European countries. For this purpose, 520 individuals from four Hungarian, two Slovakian and two Romanian countries were investigated by measuring inorganic arsenic and methylated arsenic metabolites in urine by high performance liquid chromatography with hydride generation and inductively coupled plasma mass spectrometry. Arsenic in drinking water was determined by atomic absorption spectrometry. Significantly higher concentrations of arsenic were found in both the water and the urine samples from the Hungarian counties (median: 11 and 15 microg dm(-3), respectively; p < 0.001) than from the Slovakian (median: 0.94 and 4.5 microg dm(-3), respectively) and Romanian (median: 0.70 and 2.1 microg dm(-3), respectively) counties. A significant correlation was seen between arsenic in water and arsenic in urine (R(2)= 0.46). At low water arsenic concentrations, the relative amount of dimethylarsinic acid (DMA) in urine was increased, indicating exposure via food. Also, high body mass index was associated with higher concentrations of arsenic in urine (p= 0.03), mostly in the form of DMA. Smokers had significantly higher urinary arsenic concentrations than non-smokers (p= 0.03). In conclusion, elevated arsenic exposure via drinking water was prevalent in some of the counties. Exposure to arsenic from food, mainly as DMA, and cigarette smoke, mainly as inorganic arsenic, are major determinants of arsenic exposure at very low concentrations of arsenic in drinking water.  相似文献   

16.
Nineteen soil samples were collected in and around Songshan coking plant in Guangdong province of China and analyzed for eighteen polycyclic aromatic hydrocarbons (PAHs) by gas chromatography-mass spectrometry (GC-MS). The total concentration of PAHs ranged from 2.36 to 1146.39 mg kg(-1) dry weight, varying significantly among the sampling sites, most individual PAHs were correlated with each other. A cluster analysis was performed to examine the correlation of PAH distribution, five groups were observed with sample types in the coking plant. 2-3 ring PAHs were predominant in group I and II, while 4-5 ring PAHs showed great abundance in group III, IV and V, which contributed to the distance from the emission sources in the coking plant and the behaviors of particle-bound and gaseous PAHs. The ratios of Flu?:?(Flu + Pyr), BaA?:?(BaA + Chr), InP?:?(InP + BgP) and Ant?:?(Ant + Phen) ratios were 0.51-0.87, 0.16-0.89, 0.47-0.68 and 0.03-0.60, respectively. The total index of all studied soils was > 6, indicating that the source of the PAHs in coking plant soils were from the pyrolysis processes. Health risk assessments were carried out by dermal PAH exposure data to quantify cancer risk. The resultant lifetime exposure levels due to TEQ(BaP) desorbed onto skin for workers ranged from 2.25 × 10(-7) to 7.86 × 10(-5) mg kg(-1) per day, and the estimated cancer risks were between 8.45 × 10(-6) and 2.94 × 10(-3), indicating that the dermal exposures of PAHs to coking workers might be acceptable in most soil sites.  相似文献   

17.
Particle-bound PAHs were measured at three sites in southeastern Spain (an urban background location, a suburban-industrial site in the vicinity of two cement plants and a rural area) in order to investigate the influence of the type of location on PAH concentrations. A clear influence of cement production on particulate PAH levels could not be established since for the urban background and suburban-industrial sites the average concentrations of total PAHs in the PM2.5 fraction were very similar (1.085 and 1.151 ng m(-3), respectively), with benzo[b+k]fluoranthene and chrysene as the predominant compounds. Diagnostic ratios, used to identify PAH emission sources, pointed to traffic as the main source of particulate PAH at both locations. As expected, PAH levels at the rural site were significantly lower (0.408 ng m(-3) in the PM10 fraction) due to increasing distance from the emission sources. PAH seasonal variations at the urban background and suburban-industrial sites were the same as reported in many previous studies. Average winter to summer ratios for total PAHs were 4.4 and 4.9 for the urban background and industrial sites, in that order. This seasonal cycle could be partially explained by the higher temperature and solar radiation during summer enhancing PAH evaporation from the particulate phase and PAH photochemical degradation, respectively. The study of PAH distribution between the fine and coarse fraction at the urban site revealed that on average around 80% of total PAHs were associated with fine particles.  相似文献   

18.
The levels and possible sources of 16 priority polycyclic aromatic carbons (PAHs) in the sediments from the Yellow River Delta (YRD) were investigated. The total PAH concentrations ranged from 23.9 to 520.6 microg kg(-1) with a mean value of 150.9 microg kg(-1), indicating low or medium levels compared with reported values of other deltas. The concentrations of the 16 individual PAHs presented varied profiles among different regions. The ecological risk assessment of PAHs showed that adverse effects would rarely occur in the sediments of the YRD based on the effect range-low quotients and the probability risk assessment. The PAH compositions and the principal component analysis (PCA) with multiple linear regression (MLR) uniformly presumed the mixed sources of pyrogenic- and petrogenic-deriving PAHs in the YRD. By PCA with MLR, the contributions of major sources were quantified as 36.4% from oil burning, 33.1% from biomass combustion, and 30.5% from diesel emission sources.  相似文献   

19.
The exposure characterisation described in this paper for 135 copper refinery workers (45 females, 90 males) focuses on the concentrations of copper, nickel and other trace elements in the inhalable aerosol fractions, as well as in the water-soluble and water-insoluble subfractions. Some information is also provided on the thoracic and respirable aerosol fractions. Further, results are presented for volatile hydrides of arsenic and selenium released in the copper purification steps of the electrorefining process. For the pyrometallurgical operations, a comparison of the geometric means for the inhalable aerosol fraction indicated that water-soluble copper levels were on average 19-fold higher compared to nickel (p < 0.001) and a significant association was evident between them (r = 0.87, p < 0.001); for the insoluble subfraction, the copper : nickel ratio was 12.5 (p < 0.001) and the inter-element correlation had r = 0.98 and p < 0.001. Although for the electrorefinery workers the relative inhalable concentrations of copper and nickel were not significantly different (p > 0.05), the corresponding inter-element associations were: slope of 7.7, r= 0.54, p < or =0.001 for the water-soluble subfraction and slope of 1.3, r = 0.71 and p < or =0.001 for the water-insoluble subfraction. On average, a good proportion of the inhalable copper and nickel were found in the thoracic (40%) and respirable (20%) aerosol fractions. Cobalt air concentrations were generally low with geometric means and 95% confidence intervals of 3.1 (2.4-4.2)microg m(-3) (pyrometallurgical workers) and 0.3 (0.4-0.5) microg m(-3)(electrorefinery workers). Similarly, the maximum concentrations of cadmium and lead were low, respectively 4 and 25 microg m(-3). Of the hydrides, tellurium and antimony could not be detected, but for the arsenic (arsine) and selenium hydrides measurable exposure occurred for almost all electrorefinery workers, although the levels were generally low at 0.2 microg m(-3).  相似文献   

20.
A study has been carried out to assess the contribution of Polycyclic Aromatic Hydrocarbons (PAHs) from asphalt plant operation, utilising Benzo(a)pyrene (BaP) as a marker for PAHs, to the background air concentration around asphalt plants in the UK. The purpose behind this assessment was to determine whether the use of published BaP emission factors based on the US Environmental Protection Agency (EPA) methodology is appropriate in the context of the UK, especially as the EPA methodology does not give BaP emission factors for all activities. The study also aimed to improve the overall understanding of BaP emissions from asphalt plants in the UK, and determine whether site location and operation is likely to influence the contribution of PAHs to ambient air quality. In order to establish whether the use of US EPA emissions factors is appropriate, the study has compared the BaP emissions measured and calculated emissions rates from two UK sites with those estimated using US EPA emission factors. A dispersion modelling exercise was carried out to show the BaP contribution to ambient air around each site. This study showed that, as the US EPA methodology does not provide factors for all emission sources on asphalt plants, their use may give rise to over- or under-estimations, particularly where sources of BaP are temperature dependent. However, the contribution of both the estimated and measured BaP concentrations to environmental concentration were low, averaging about 0.05 ng m(-3) at the boundary of the sites, which is well below the UK BaP assessment threshold of 0.25 ng m(-3). Therefore, BaP concentrations, and hence PAH concentrations, from similar asphalt plant operations are unlikely to contribute negatively to ambient air quality.  相似文献   

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