Assessment of biological community in riparian zone contaminated by PAHs: Linking source apportionment to biodiversity

Riparian zone, an important land-water interface, plays an essential role in maintaining the ecological health of rivers, whereas the effects of Polycyclic aromatic hydrocarbons (PAHs) on the health of biological communities in riparian groundwater remain undetermined. To understand the responses of multiple communities to environmental variables, the distribution and ecosystem risk of 16 PAHs have been investigated in the Beiluo River, China. The distribution of multiple communities in riparian groundwater was investigated by environmental DNA metabarcoding, including 16S rRNA, 18S rRNA, and COI gene sequencing for bacteria, microbial eukaryotes (including algae, fungi, and protozoa), and metazoan, respectively, followed by correlation analysis between multiple communities and PAH contamination levels. The concentration of PAHs in the Beiluo River ranged largely from 35.32 to 728.59 ng/L. Here, the Shannon's diversity index of bacteria (Firmicutes) decreased possibly due to the occurrence of Pyrene, which mainly derives from coal and biomass combustion. Furthermore, the reduced richness of fungi (Ascomycota, Basidiomycota) and algae (Chlorophyta, Chrysophyceae) can be attributed to the presence of medium molecular weight (MMW) PAHs (Pyrene, Benz(a)anthracene, Chrysene), and low molecular weight (LMW) PAHs (Naphthalene, Fluorene, Phenanthrene). The richness and Shannon's diversity index of metazoan (Arthropoda) were promoted owing to MMW PAHs (Chrysene, Fluoranthene) generated from coal and biomass combustion and traffic emission. The ecological risk of PAHs in the groundwater environment of the Beiluo River was characterized as low to medium, where LMW and MMW PAHs posed higher risk than the high molecular weight (HMW) compounds. Overall, this study provides insights into the structures of riparian multi-biological communities altered by PAHs.

Assessment of concentration of polycyclic aromatic hydrocarbons (PAHs) in vegetables from farms in Accra, Ghana

Ingestion of leafy vegetables is an important dietary component of most Africans due to its health benefits. High levels of polycyclic aromatic hydrocarbons (PAHs) in the leafy vegetables may pose a significant health hazard to the consumers. Rose/Hibiscus, Chinese cabbage, lettuce, and garden egg leaves from farms along the Nima Creek, Accra, were selected. At each sampling site, the vegetable was uprooted and cut into leaves, stem, and root and analyzed differently. The GC-MS method was employed in the identification and quantification of 16 PAHs in the samples. The analysis was done at CSIR - Water Research Institute Organic Laboratory. The results obtained show concentrations of acenapththylene, acenapthene, benzo[a]anthracene, benzo[b]fluoranthene, and benzo[a]pyrene (except chrysene and pyrene which were found in garden egg leaves and Chinese cabbage respectively), while naphthalene was detected in all the vegetables. The mean concentration of phenanthrene in leaves, stem, and roots of Chinese cabbage vegetable varies according to the following order: roots (0.744 ± 0.16 μg/kg) ≥ leaves (0.598 ± 1.21 μg/kg) ≥ stem (0.327 ± 1.01 μg/kg). From the results of the isomeric ratios, the source of the PAHs in the leafy vegetables are from mixed sources, i.e., either pyrogenic and petrogenic origins. This calls for the formulation of stringent policies on the importation of over-age vehicles into the countries as well as on the indiscriminate burning of materials containing PAHs.

PAHs contamination in edible gastropods from north Patagonian harbor areas

PAHs are persistent pollutants released into the environment by fossil fuels burning and leak during petroleum operations. Associated with suspended particles upon entering marine ecosystem are accumulated by benthic fauna. Human exposure occurs mainly from ingestion such as gastropods consumption. The objective was to determine PAHs in sediments and in the marine gastropod Buccinanops globulosus in sites with different maritime and urban influences. In sampling sites located 20 km from the harbor, PAHs were non-detected; while in harbor gastropods, the level of PAH4 was exceeded according to international normative. Level of dibenzo[a,h]anthracene in sediments was between the ISQG and PEL. Since these are the first results of PAHs in edible gastropods in South America, we concluded that PAHs can be dangerous for consumers according to ingestion frequency. Integrative studies are necessary to evaluate the interaction among pollutants in maritime areas and the incidence in human health due to shellfish consumption.

Spatial variation of polycyclic aromatic hydrocarbons (PAHs) in surface sediments from rivers in hilly regions of Southern China in the wet and dry seasons

Seasonal variations of polycyclic aromatic hydrocarbons (PAHs) in the surface sediments from 13 rivers in hilly regions of southern China were studied. Concentrations of PAHs analyzed in the wet season were higher than those analyzed in the dry season, with residues ranging from 74.3 to 1930.9 ng g^-1 dw in the wet season and from 96.9 to 1388.9 ng g^-1 dw in the dry season. The primary contributors were 3- and 4-ringed congeners accounting for 59.8% ± 10.1% and 58.3% ± 9.3% of the identified PAHs in the wet and the dry seasons, respectively. Proximity to sources and locations susceptible to high atmospheric depositional inputs results in high concentrations of PAH. Diagnostic ratios have indicated that the sources of PAHs in different seasons make no apparent difference. Furthermore, a principal component analysis and multiple linear regression (PCA-MLR) studies indicate that combustion sources such as vehicle emissions and coal combustion are the primary sources of PAHs. Toxicological risk assessments based on TEQ^care suggested that Benzo[a]pyrene, benz[a]anthracene, dibenz[a,h]anthracene could pose high ecological risks in this area.

Appraisement, source apportionment and health risk of polycyclic aromatic hydrocarbons (PAHs) in vehicle-wash wastewater, Pakistan

Vehicle-wash wastewater (VWW) contains elevated concentrations of different petrochemicals including polycyclic aromatic hydrocarbons (PAHs), a carcinogenic group of organic compounds. This study investigates the discharge of PAHs present in the untreated wastewater of vehicle-wash stations (VWS) located in district Peshawar, Pakistan. The data obtained was being novel with the detection of 16 USEPA PAHs (both individuals and total) and compared with earlier studies and international standards. The ∑16PAHs in wastewater from light vehicle-wash stations (LVWS) and heavy vehicle-wash stations (HVWS) ranged from 245-429μg/l and 957-1582μg/l, respectively. A significant difference (p<0.01) was observed in PAHs discharged from LVWS and HVWS. The projected ∑16PAHs discharge from both HVWS (92% of total generated PAHs) and LVWS (8%) was about 5109.9 g per annum. According to PAH diagnostic ratios, PAHs were both petrogenic (chrysene/benz(a)anthracene, low molecular weight/high molecular weight) and pyrogenic (phenanthrene/anthracene, fluoranthene/pyrene, fluoranthene/fluoranthene+pyrene) in origin. The highest toxic equivalent quotient (TEQ) value was shown by benzo(a)pyrene (21.6μg/l) followed by dibenz(ah)anthracene (9.81μg/l) in wastewater from HVWS. However, in LVWS the case was reversed with highest value (7.54μg/l) for dibenz(ah)anthracene followed by benzo(a)pyrene (3.54μg/l). The lowest TEQ value was indicated for phenanthrene (0.007μg/l) in wastewater of LVWS, while pyrene showed the lowest value (0.007μg/l) in wastewater of HVWS. The results indicated that VWS contribute significant amount of PAHs each year, which is of great concern regarding water quality, ecological and human health risk. This is the first systematic and comprehensive research related with generation of PAHs load per day, week, month and annum from VWS, their source apportionment and health effects in Pakistan.

Study of persistent toxic pollutants in a river basin-ecotoxicological risk assessment

This study presents a complementary approach for the evaluation of water quality in a river basin by employing active and passive sampling. Persistent toxic pollutants representing three classes: organochlorinated pesticides (OCPs), polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs), were studied in grab water samples, in passive samplers/SemiPermeable Membrane Devices (SPMDs) and in fish tissues collected along the Strymonas River, northern Greece at three sampling campaigns during the year 2013. Almost all the target compounds were detected in the study river of Strymonas, northern Greece at the periods of high rainfall intensity and/or low flow-rate. The most frequently detected compounds were 1,2-benzanthracene, benzo(a)pyrene, benzo(b)fluoranthene, endosulfan I, endosulfan II, endosulfan sulfate, endrin aldehyde, fluorene, methoxychlor, polychlorinated biphenyl PCB 28, PCB 180 and pyrene. The family of DDT compounds and aldrin were also occasionally detected. Agricultural run-off and waste effluents are the main sources of hydrophobic organic compounds in the river basin. The use of SPMDs allowed the detection of more micropollutants than active sampling (31 vs. 16, respectively). Results showed relatively low risk however the potential risk associated with micropollutants such as 1,2-benzanthracene, benzo(b)fluoranthene, p,p-dichlorodiphenyldichloroethane (DDD), endosulfan II, methoxychlor, PCB 180 and pyrene should not be neglected. Performing risk assessment based on passive sampling, more information was obtained about temporal and spatial variation. SPMDs could be applied as a pre-evaluation before chemical monitoring in biota.

Polycyclic aromatic hydrocarbons in commercial brands of dry whole soybeans for direct human consumption

A total of 13 polycyclic aromatic hydrocarbons (PAHs) were surveyed in dry whole soybeans (Glycine max L.) sold for human consumption. The analysed samples were commercialised in vegetarian shops and food stores in Southern Brazil regions. The determination of PAHs levels was carried out by high performance liquid chromatography (HPLC)with fluorescence detection. PAHs were present in 89.7% of the samples. Chrysene (Chy) and 5 methyl chrysene (5MeChy) were the main PAHs detected (76.9% and 71.8%, respectively) followed by dibenzo(ai)pyrene (DaiP), however in a much less percentage of samples (23.1%). Apart from those PAHs, also benzo(a)antracene (BaA), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (BkF) and benzo(a)pyrene(BaP) were found. The ΣPAH levels in the positive samples ranged from 0.80 to 38.78 µg kg-1, with exception of one sample that reached 204.46 µg kg-1 (ΣPAHs of six compounds). Despite the present contamination there are no maximum limits set for PAHs in soybeans.

Bioaccessibility of nitro- and oxy-PAHs in fuel soot assessed by an in vitro digestive model with absorptive sink

Ingestion of soot present in soil or other environmental particles is expected to be an important route of exposure to nitro and oxygenated derivatives of polycyclic aromatic hydrocarbons (PAHs). We measured the apparent bioaccessibility (B_app) of native concentrations of 1-nitropyrene (1N-PYR), 9-fluorenone (9FLO), anthracene-9,10-dione (ATQ), benzo[a]anthracene-7,12-dione (BaAQ), and benzanthrone (BZO) in a composite fuel soot sample using a previously-developed in vitro human gastrointestinal model that includes silicone sheet as a third-phase absorptive sink. Along with B_app, we determined the 24-h sheet-digestive fluid partition coefficient (K_s,24h), the soot residue-fluid distribution ratio of the labile sorbed fraction after digestion (K_r,lab), and the maximum possible (limiting) bioaccessibility, B_lim. The B_app of PAH derivatives was positively affected by the presence of the sheet due to mass-action removal of the sorbed compounds. In all cases B_app increased with imposition of fed conditions. The enhancement of B_app under fed conditions is due to increasingly favorable mass transfer of target compounds from soot to fluid (increasing bile acid concentration, or adding food lipids) or transfer from fluid to sheet (by raising small intestinal pH). Food lipids may also enhance B_app by mobilizing contaminants from nonlabile to labile states of the soot. Compared to the parent PAH, the derivatives had larger K_r,lab, despite having lower partition coefficients to various hydrophobic reference phases including silicone sheet. The B_lim of the derivatives under the default conditions of the model ranged from 65.5% to 34.4%, in the order, 1N-PYR > ATQ > 9FLO > BZO > BaAQ, with no significant correlation with hydrophobic parameters, nor consistent relationship with B_lim of the parent PAH. Consistent with earlier experiments on a wider range of PAHs, the results suggest that a major determinant of bioaccessibility is the distribution of chemical between nonlabile and labile states in the original solid.

Evaluation of genetic toxicity caused by acid mine drainage of coal mines on fish fauna of Simsang River, Garohills, Meghalaya, India

Fishery ecology of the Simsang River, Meghalaya is being threatened by large scale environmental degradation due to acid mine drainage (AMD) of coal mines. In the present paper, effort has been made to evaluate the genotoxicity caused due to AMD of coal mines on Channa punctata under laboratory condition through comet assay, micronucleus and chromosome aberration tests. Water samples were collected seasonally from affected and unaffected sites of the River and physico-chemical quality of water indicated low pH (4.6), high concentration of sulphates (270mgL(-1)) and iron (7.2mgL(-1)) beyond permissible limits. Polycyclic aromatic hydrocarbon (PAH) showed highest concentration of 4-ring PAH and Benzo[a]anthracene was the most important pollutant in the water collected from affected sites. The highest and the lowest mean concentrations of PAHs were estimated in monsoon and winter season, respectively. The index of DNA damage assessed by comet assay, micronucleus and chromosome aberration tests demonstrated significant differences season wise in different sampling sites. Frequency of DNA-damaged cells was found highest in the water samples collected from affected site in monsoon season.

Use of the Integrated Biomarker Response to Measure the Effect of Short-term Exposure to Dibenz[a,h]anthracene in Common carp (Cyprinus carpio)

Dibenz[a,h]anthracene (DbA) is a polycyclic aromatic hydrocarbon that is released into the environment through incomplete combustion of gasoline, cigarettes, and coal tar. The effects of short-term (10 days) exposure of common carp (Cyprinus carpio) to DbA (0-50 µg L(-1)) were evaluated using the following four biomarkers: DNA damage, 7-ethoxyresorufin-O-deethylase (EROD) activity, acetylcholinesterase (AChE) activity, and vitellogenin (VTG) levels. An integrated biomarker response (IBR) was calculated for exposure to DbA, and the results were compared with those in our previous study of two other PAHs, benzo[k]fluoranthene (BkF) and benzo[a]pyrene (BaP). DbA exposure resulted in a significant (p < 0.05) increase in DNA damage, EROD activity, and VTG levels relative to the control. By contrast, DbA did not affect AChE activity. The IBR increased as the concentration of DbA increased. Based on the IBR values, the order of toxicity for the PAHs was BkF > BaP > DbA. Our results suggest that the IBR can be used as a quantitative tool for evaluating the responses of multiple biomarkers to PAH exposure.

Detection of benz[j]aceanthrylene in urban air and evaluation of its genotoxic potential

Benz[j]aceanthrylene (B[j]A) is a cyclopenta-fused polycyclic aromatic hydrocarbon with strong mutagenic and carcinogenic effects. We have identified B[j]A in air particulate matter (PM) in samples collected in Stockholm, Sweden and in Limeira, Brazil using LC-GC/MS analysis. Determined concentrations ranged between 1.57 and 12.7 and 19.6-30.2 pg/m(3) in Stockholm and Limeira, respectively, which was 11-30 times less than benzo[a]pyrene (B[a]P) concentrations. Activation of the DNA damage response was evaluated after exposure to B[j]A in HepG2 cells in comparison to B[a]P. We found that significantly lower concentrations of B[j]A were needed for an effect on cell viability compared to B[a]P, and equimolar exposure resulted in significant more DNA damage with B[j]A. Additionally, levels of γH2AX, pChk1, p53, pp53, and p21 proteins were higher in response to B[j]A than B[a]P. On the basis of dose response induction of pChk1 and γH2AX, B[j]A potency was 12.5- and 33.3-fold higher than B[a]P, respectively. Although B[j]A levels in air were low, including B[j]A in the estimation of excess lifetime cancer risk increased the risk up to 2-fold depending on which potency factor for B[j]A was applied. Together, our results show that B[j]A could be an important contributor to the cancer risk of air PM.

Determination of oxygenated and native polycyclic aromatic hydrocarbons in urban dust and diesel particulate matter standard reference materials using pressurized liquid extraction and LC-GC/MS

The objective of this study was to develop a novel analytical chemistry method, comprised of a coupled high-performance liquid chromatography-gas chromatography/mass spectrometry system (LC-GC/MS) with low detection limits and high selectivity, for the identification and determination of oxygenated polycyclic aromatic hydrocarbons (OPAHs) and polycyclic aromatic hydrocarbons (PAHs) in urban air and diesel particulate matter. The linear range of the four OPAHs, which include 9,10-anthraquinone, 4H-cyclopenta[def]phenanthrene-4-one, benzanthrone, and 7,12-benz[a]anthraquinone, was 0.7 pg-43.3 ng with limits of detection (LODs) and limits of quantification (LOQs) on the order of 0.2-0.8 and 0.7-1.3 pg, respectively. The LODs in this study are generally lower than values reported in the literature, which can be explained by using large-volume injection. The recoveries of the OPAHs spiked onto glass fiber filters using two different pressurized liquid extraction (PLE) methods were in the ranges of 84-107 and 67-110 %, respectively. The analytical protocols were validated using the following National Institute of Standards and Technology standard reference materials: SRM 1649a (Urban Dust), SRM 1650b (Diesel Particulate Matter), and SRM 2975 (Diesel Particulate Matter, Industrial Forklift). The measured mass fractions of the OPAHs in the standard reference materials (SRMs) in this present study are higher than the values from the literature, except for benzanthrone in SRM 1649a (Urban Dust). In addition to the OPAHs, 44 PAHs could be detected and quantified from the same particulate extract used in this protocol. Using data from the literature and applying a two-sided t test at the 5 % level using Bonferroni correction, significant differences were found between the tested PLE methods for individual PAHs. However, the measured mass fractions of the PAHs were comparable, similar to, or higher than those previously reported in the literature.

Superoxide mediated photomodification and DNA damage induced apoptosis by Benz(a)anthracene via mitochondrial mediated pathway

Benz(a)anthracene (BA) is an ubiquitous environmental pollutant of polycyclic aromatic hydrocarbon's (PAHs) family. We showed superoxide (O2(-)) catalyzed BA photo modification and apoptosis in HaCaT keratinocytes under sunlight exposure. O2(-) generation was confirmed by quenching through superoxide dismutase (SOD). BA induced photocytotoxicity were investigated through MTT and NRU assay. We proposed DNA insults such as single and double strand breakage and CPDs formation which results in cell cycle arrest and apoptosis by photosensitized BA. BA induced apoptosis was caspase dependent and occurred through a mitochondrial pathway. Reduction of mitochondrial membrane potential, translocation of Bax to mitochondria and cytochrome c release favors involvement of mitochondria in BA phototoxicity. AO/EB double staining and TEM analysis also support apoptotic cell death. We propose a p21 regulated apoptosis via expression of Bax, and cleaved PARP under sunlight exposure. Thus, we conclude that it is imperative to avoid solar radiation during peak hr (between 11A.M. and 3P.M.) when the amount of solar radiation is high, in the light of DNA damage which may lead to mutation or skin cancer through photosensitized BA under sunlight exposure. Concomitantly, investigation is urgently required for the photosafety of BA photoproducts reaching in the environment through photomodification.

Occurrence of polycyclic aromatic hydrocarbons in the Soan River, Pakistan: insights into distribution, composition, sources and ecological risk assessment

Present study investigates the occurrence, distribution and sources of ∑17 polycyclic aromatic hydrocarbons (PAHs) in the surface water of Soan River, Pakistan. The concentrations of total PAHs ranged from 61 to 207 ng/l. Low molecular weight (LMW) PAHs were recorded higher in concentrations (64.7 percent) as compared to high molecular weight (HMW) PAHs (35.6 percent). Principal component analysis (PCA) revealed domestic and industrial wastewater discharge, vehicular exhaust, petroleum residues and biomass combustion as the main sources for PAHs contamination. Using the USEPA toxic equivalency factor (TEF) approach: Benzo(a)Pyrene and Dibenzo(a,h)Anthracene contributed highly carcinogenic exposure equivalent. The surface water of the Soan River is found to be slightly polluted with PAHs thereby posing health risks to aquatic bodies.

Use of constant wavelength synchronous spectrofluorimetry for identification of polycyclic aromatic hydrocarbons in air particulate samples

We have developed a simple, rapid, inexpensive method for the identification of fluoranthene (Flan), benz(a)anthracene (BaA), benzo(a)pyrene (BaP), benzo(k)fluoranthene (BkF), pyrene (Pyr), benz(ghi)perylene (BghiP) in suspended particulate matter in an urban environment of Delhi. Suspended particulate matter samples of 24h duration were collected on glass fiber filter papers. Polycyclic aromatic hydrocarbons (PAHs) were extracted from the filter papers using dichloromethane (DCM) and hexane with ultrasonication method. Comparison of the characteristic emission of spectra of PAHs with standard spectra indicated the degree of condensation of aromatic compounds present in investigated mixtures. It was also possible to identify some individual compounds. However, this identification could be more effective with the use of the respective values of Δλ parameter for each particular component of the mixture.

[Characterization of PAHs in fly ashes from coke production]

In order to investigate the characteristics of polycyclic aromatic hydrocarbons (PAHs) in ashes from coking, PAHs in ashes from three coke production plants were analyzed with GC-MS, and the distribution characteristics of PAHs and potential toxicity risk were discussed. The sum of 16 EPA prior PAHs varied from 8.17 x 10(2) to 5.17 x 10(3) microg x g(-1). PAH contents from the coke oven (stamp charging) with the height of 3.2 m were two times higher than those from the one (top charging) with the height of 6.0 m, and PAHs in ashes from coal charging were significantly higher than those from coke pushing in the same plant. Four-ring and five-ring PAHs were the dominant species in ashes from coking and the sum of them accounted for more than 80.00% of total PAHs. Chrysene (Chr), benzo [a] anthracene (BaA) and benzo [b] fluoranthene (BbF) were abundant in all ash samples. The content of total BaP-based toxic equivalency (BaPeq) ranged from 1.64 x 10(2) to 9.57 x 10(2) microg x g(-1). From the carcinogenic point of view, besides benzo [a] pyrene (BaP), dibenz [a,h] anthracene (DbA) contributed most to the overall toxicity of PAHs, followed by BaA and BbF. BaPeq concentration from coal charging was 5.21-fold higher than that from coke pushing, indicating that different reuse ways should be considered based on their specific toxicity profiles of PAHs.

Identification and quantitative confirmation of dinitropyrenes and 3-nitrobenzanthrone as major mutagens in contaminated sediments

Polar fractions of a sediment extract of the industrial area of Bitterfeld, Germany, have been subjected for effect-directed identification of mutagens using the Ames fluctuation assay with TA98. Mutagenicity could be well recovered in several secondary and tertiary fractions. Dinitropyrenes and 3-nitrobenzanthrone could be confirmed to contribute great shares of the observed mutagenicity. In addition, a multitude of polar polycyclic aromatic compounds has been tentatively identified in mutagenic fractions including nitro-PAHs, azaarenes, ketones, quinones, hydroxy-compounds, lactones and carboxylic acids although their contribution to mutagenicity could not be quantified due to a lack of standards. Diagnostic Salmonella strains YG1024 and YG1041 were applied to confirm the contribution of nitro-aromatic compounds. We suggest the inclusion of dinitropyrenes and 3-nitrobenzanthrone into sediment monitoring in order to minimize the mutagenic risk to aquatic organisms and to human health.

PM 2.5 and PAH concentrations in urban atmosphere of Tiruchirappalli, India

Airborne PM 2.5 and polycyclic aromatic hydrocarbons (PAHs) bound to it were determined from March 2009 to February 2010 at different locations in Tiruchirappalli City, Southern India using fine particulate sampler and high performance liquid chromatography. Average ∑9 PAHs concentrations at four sampling stations were 333.7, 202.6, 265.9, and 232.7 ng/m(3), respectively. Highest concentration of PAHs was observed during northeast monsoon season (301.5 ng/m(3)) and lowest in southwest monsoon (216 ng/m(3)). Low and medium molecular weight PAHs such as phenanthrene, anthracene, benzo(a)anthracene and chrysene were observed in all seasons. Principal compound analysis revealed gasoline and diesel vehicular emissions as major sources for PAHs compounds.

Nanofabrication of bio-self assembled monolayer and its electrochemical property for toxicant detection

Cyclic voltammetry (CV) has been used to investigate the electrochemical behavior of a glutathione (GSH) self assembled monolayer on modified gold electrodes (Bio-SAM). The GSH monolayer exhibits an influence on electrode surface activity. Electrochemically immobilized dsDNA onto a Cyt c/GSH-SAM/Au electrode, which is useful for the fabrication of a nanobiosensing device. The immobilized Cyt c followed by dsDNA immobilized films maintained its surface activity and finally dsDNA/Cyt c/GSH-SAM/Au electrode, targeted for the detection of toxicants. The films were characterized by CV, DPV, and AFM. The differential pulse voltammetry (DPV) technique was applied to detect three kinds of common toxins, 2-aminoanthracene (2-AA), 3-bromobenzanthrone (3-BBA) and bisphenol A (BPhA). The electrochemical signals showed good inverse relationship with the increase of concentrations of toxicants. Our proposed system based on electrochemical method with nanoscale film technology can be applied at highly sensitive biosensor for detecting various toxic chemicals.

POP accumulation in the food chain: Integrated risk model for sewage sludge application in agricultural soils

Because of its benefits to soil and crops, sewage sludge application on agricultural soils is a managing practice of increasing use. However, this practice may lead to contamination of the food chain, especially by persistent organic pollutants (POPs). The main objective of this study was to integrate probabilistic multimedia models to predict the accumulation of POPs in the food chain and the related risks to humans, as a consequence of sludge application on soil. For that, four models were integrated: (i) soil fate, (ii) plant, (iii) food chain and (iv) exposure and risk. These models were applied for two scenarios (occupational and non-occupationally exposed populations) in a time span of 30 years. The variability of the inputs and outputs was also considered. The model was applied to a case-study of 4 POPs (2,3,7,8TCDD, PCB 180, benzo(a)pyrene, and dibenzo(a,h)anthracene) in an agricultural soil located in Catalonia (NE of Spain). Some differences in cancer risk due to POP exposure were appreciated between both evaluated scenarios. However, all values were below the threshold levels. With the exception of 2,3,7,8TCDD, all the contaminants reached steady state on soil in the first five years of the evaluation. Concentration levels in food (vegetables, meat and milk) were linearly correlated to those in soils. Air inhalation was noted to be an occupational exposure route of minor importance. Sensitivity analysis for 2,3,7,8TCDD showed that exposure parameters were responsible for most of the variability in the results.

Fractionation of polycyclic aromatic hydrocarbon residues in soils

Understanding the forms and availabilities of polycylic aromatic hydrocarbons (PAHs) would have considerable benefits for their risk assessment, and is of crucial importance for food security and remediation strategies in contaminated sites. In this work, the forms of six PAHs (fluorene, phenanthrene, fluoranthene, pyrene, benzo[a]anthracene, and benzo[a]pyrene) in soils were separated into three fractions including a desorbing fraction, a non-desorbing fraction, and a bound residual fraction using a sequential extraction mass balance approach. The desorbing and non-desorbing fractions were extracted with hydroxypropyl-beta-cyclodextrin (HPCD) and dichloromethane:acetone (1:1, vol/vol), respectively. The desorbing and non-desorbing fractions always dominated the total PAH content in soils. The proportion of bound PAH residue in nonsterilized soils was small (<16%), and even smaller (4.5%) in sterilized soils. The concentrations of the desorbing fraction of PAHs as well as the percentage of this fraction to the total PAH content in soils clearly decreased in 0-16 weeks, which may be due to microbial biodegradation and its transfer to other fractions in soils. The concentrations of the non-desorbing PAH fractions increased in sterilized soils, while remaining nearly constant or decreasing to some extent in nonsterilized soils after 16 weeks. The proportion of non-desorbing PAH fractions significantly increased in 16 week-incubation, and this proportion was positively correlated with the molecular weights of the PAHs tested, indicating that larger PAHs are more likely to be present in non-desorbing fractions. The bound PAH residue tended to increase at first and decrease thereafter over the 0-16-week period, and microbes played an important role in the formation of bound residue.

[Air quality vs. morbidity to lung cancer in selected provinces and localities of the Silesian region]

The objective of the study was analysis of the relationship between the quality of ambient air and icidence of lung cancer based on the results of measurements of selected indicator substances and epidemiological data from the localities/provinces in the Silesian Region. The levels of pyrene, benzoanthracene, benzopyrene and dibenzo(a,h)anthracene were analysed, as well as the concentrations of PM10 fractions sampled on glass fibre filters at sampling stations in 5 localities and 8 provinces in the Silesian Region. The classification of morbidity to lung cancer for the localities and provinces in the study was presented based on the data from the Regional Silesian Cancer Registry. In the group of males a relationship was observed between an increased morbidity to lung cancer and an increasing concentration of pyrene and PM10 respirable dust fraction in ambient air. The preliminary analyses confirmed the strong effect of the quality of ambient air on incidence of lung cancer in the Silesian Region.

Sensitive biomarker of polycyclic aromatic hydrocarbons (PAHs): urinary 1-hydroxyprene glucuronide in relation to smoking and low ambient levels of exposure

The study was conducted in a Chinese population with occupational or environmental exposures to polycyclic aromatic hydrocarbons (PAHs). A total of 106 subjects were recruited from coke-oven workers (workers), residents in a metropolitan area (residents) and suburban gardeners (gardeners). All subjects were monitored twice for their personal exposures to PAHs. The biological samples were collected for measurements of 1-hydroxypyrene (1-OHP) and cotinine in urine. The geometric means of personal exposure levels of pyrene, benz(a)anthracene (BaA) and benzo(a)pyrene (BaP) in workers were 1.470, 0.978 and 0.805 microg m-3, respectively. The corresponding levels in residents were 0.050, 0.034 and 0.025 microg m-3; and those in gardeners were 0.011, 0.020 and 0.008 microg m-3, respectively. The conjugate of 1-OHP with glucuronide (1-OHP-G) is the predominant form of pyrene metabolite in urine and it showed strong associations with exposures not only to pyrene, but also to BaA, BaP and total PAHs. Most importantly, a significant difference in 1-OHP-G was even detected between the subgroups with exposures to BaP at < 0.010 and > 0.010 but < 0.020 microg m-3, suggesting that 1-OHP-G is a good marker that can be used for the risk assessment of BaP exposure at levels currently encountered in ambient air. Furthermore, multiple regression analyses of 1-OHP-G on PAHs exposure indicated that cigarette smoke was a major confounding factor and should be considered and adjusted for while using 1-OHP to estimate PAHs exposure.

Identification of polycyclic aromatic hydrocarbons (PAHs) in suspended particulate matter by synchronous fluorescence spectroscopic technique

The synchronous fluorescence (SF) technique has been used in the identification of polycyclic aromatic hydrocarbons (PAHs) from air particulate sample in an urban environment of Delhi, Jawaharlal Nehru University. Suspended particulate matter samples of 24h duration were collected on glass fiber filter papers. PAHs were extracted from the filter papers using dichloromethane (DCM)+hexane with ultrasonication method. Qualitative measurements of the polycyclic aromatic hydrocarbons (PAHs) were carried out using the SF technique at various wavelength intervals (Deltalambda). Due to the difference in chemical structure, each PAH gives specific characteristic spectrum for each Deltalambda. Following PAHs were detected in our measurement: benz(a)anthracene (BaA), pyrene (Pyr), chrysene (Chry), fluoranthene (Flan), phenanthrene (Phen), and benz(ghi)perylene (BghiP). This is in agreement with our earlier work for determination of these PAHs using gas chromatography (GC). The seasonal variation of the PAHs was found to be maximum in winter and minimum during the monsoon.

Distribution of polycyclic aromatic hydrocarbons in thirty typical soil profiles in the Yangtze River Delta region, east China

Polycyclic aromatic hydrocarbons (PAHs) were quantified in 30 soil profiles from the Yangtze River Delta Region, in east China. Relative concentrations of PAH compounds with different benzene rings and ratios of fluoranthene to fluoranthene plus pyrene and benz(a)anthracene to benz(a)anthracene plus chrysene were used to identify the possible sources of soil PAHs. Total concentrations of 15 PAHs in topsoils ranged from 8.6 to 3881 microg kg(-1) with an average of 397 microg kg(-1). Half of the soil samples were considered to be contaminated with PAHs (>200 microg kg(-1)) and two sampling sites were heavily polluted by PAHs with concentrations >1000 microg kg(-1). Phenanthrene was found in soils below a depth of 100 cm in half of the sampling sites, but the detectable ratio of benzo(a)pyrene decreased sharply from 100% in topsoil to 0 in the 4th horizon.

APPI-MS: effects of mobile phases and VUV lamps on the detection of PAH compounds

The technique of atmospheric pressure photoionization (APPI) has several advantages over electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI), including efficient ionization of nonpolar or low charge affinity compounds, reduced susceptibility to ion suppression, high sensitivity, and large linear dynamic range. These benefits are greatest at low flow rates (i.e., Collapse

Key Words

• atmospheric pressure photoionization
• appi
• mass spectrometry
• polyaromatic hydrocarbons
• pah
• krypton
• argon
• vuv
• solvent effects
• photoabsorption cross-section

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MESH Headings

• Atmospheric Pressure
• Benz(a)Anthracenes/analysis
• Benzo(a)pyrene/analysis
• Chromatography, High Pressure Liquid
• Mass Spectrometry/instrumentation
• Mass Spectrometry/methods
• Noble Gases/chemistry
• Photochemistry/instrumentation
• Photochemistry/methods
• Pyrenes/analysis
• Solvents/chemistry

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Grants

• R43 GM063430 NIGMS NIH HHS
• R44 GM063430 NIGMS NIH HHS
• R44 GM063430-03S1 NIGMS NIH HHS
• GM063430 NIGMS NIH HHS

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Affiliation(s)

Luke Chandler Short Syagen Technologies, Inc., Tustin, California 92780, USA
Sheng-Suan Cai
Jack A Syage

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Determination of some polycyclic aromatic hydrocarbons in filter tar of Turkish cigarettes

A simultaneous determination method for the analysis of benzo[a]pyrene (BaP) and dibenzo[a,h]anthracene (DahA) in the filter tar of Turkish cigarettes has been developed. The method involved (a) the extraction of BaP and DahA with n-hexane from ACN solution in which the cigarette filters were extracted, and then (b) purification of the n-hexane extracts by elution on an XAD-2 column using n-hexane/dichloromethane (9:1, v/v) mixture. Separation and quantitative determination of BaP and DahA in the extracts were carried out by HPLC and fluorescence detection on a C18 RP column. The calculated recoveries for BaP and DahA were found in the range of 90-100% for each extraction and clean-up steps. Analysis of various filter tar of Turkish cigarettes showed that an average of 74.28 ng/filter of BaP and 5.24 ng/filter of DahA were present in Turkish cigarettes.

Breakdown products on metabolic pathway of degradation of benz[a]anthracene by a ligninolytic fungus

Cultures of the ligninolytic fungus Irpex lacteus incubated in a nutrient liquid medium degraded more than 70% of the initially applied benz[a]anthracene within 14 days. At the first step of metabolization, benz[a]anthracene was transformed via a typical pathway of ligninolytic fungi to benz[a]anthracene-7,12-dione (BaAQ). The product was further transformed by at least two ways, whereas one is complied with the anthracene metabolic pathway of I. lacteus. Benz[a]anthracene-7,12-dione was degraded to 1,2-naphthalenedicarboxylic acid and phthalic acid that was followed with production of 2-hydroxymethyl benzoic acid or monomethyl and dimethylesters of phthalic acid. Another degradation product of BaAQ was identified as 1-tetralone. Its transformation via 1,4-naphthalenedione, 1,4-naphthalenediol and 1,2,3,4-tetrahydro-1-hydroxynaphthalene resulted again in phthalic acid. None of the intermediates were identified as dead-end metabolites. Metabolites produced by ring cleavage of benz[a]anthracene using the ligninolytic fungus are firstly presented in this work.

Single-laboratory validation of a gas chromatography–mass spectrometry method for quantitation of 15 European priority polycyclic aromatic hydrocarbons in spiked smoke flavourings

An existing method was adapted to the purpose and validated in-house according to the IUPAC harmonised guideline for the determination of 15 EU priority polycyclic aromatic hydrocarbons (PAHs) in primary smoke condensates (PSCs) that are used to produce smoke flavourings for human consumption. Limits of detection (LOD) varied between 0.1 and 1.3 microg/kg, limits of quantitation (LOQ) between 0.5 and 4 microg/kg for the various PAHs in PSCs. The coefficient of variance of the repeatability was between 0.7% (benzo[a]pyrene) and 30% (dibenzo[a,h]pyrene) relative standard deviation, depending on the analyte. The recoveries varied between 100 and 102% (dibenzo[a,l]pyrene) and 69-83% (dibenzo[a,h]pyrene) over the analytical range of 5-35 microg/kg.

Assessment of 3-nitrobenzanthrone reductase activity in mammalian tissues by normal-phase HPLC with fluorescence detection

3-Nitrobenzanthrone (3-NBA) is a potent mutagen and possible human carcinogen present in diesel exhaust and airborne particulate matter. Nitroreduction is believed to play a crucial role in nitroarene activation and mutagenicity; however, quantification of nitroreduction rate in mammalian samples has proved difficult. In this study, we present a sensitive method to quantify 3-nitrobenzanthrone reductase activity in murine tissues via normal-phase HPLC with fluorescence detection of the reduced product 3-aminobenzanthrone (3-ABA). Calibration linearity was obtained for pure 3-ABA concentrations of 1-500 ng/ml (r2>0.99), with a detection limit of 0.25 ng/ml (S/N=3). Incubation time, substrate concentration, and protein concentration in the reaction mixture were optimized, and the detection limit of the enzyme assay is 0.97 pmol/min/mg protein. The apparent K(m) and V(max) for post-mitochondrial supernatant from Mutatrade markMouse liver (i.e., liver S9) were 23.9 microM and 70.2 pmol/min/mg protein, respectively. Analysis of replicate samples of Mutatrade markMouse liver and lung S9 yielded mean activity values of 39.0+/-3.0 and 61.1+/-4.3 pmol/min/mg, respectively. ANOVA revealed significant effects of tissue type and incubation condition (i.e., with or without N2). The results show significantly higher activity in lung, and, in contrast to that observed for 1-nitropyrene, incubation in open air (i.e., without N2 bubbling) causes only a marginal decrease in activity. Quantification of 3-NBA nitroreductase activity in murine tissues will provide insight into the published tissue-specific mutagenic activity of 3-NBA.

Impact of imposed anaerobic conditions and microbial activity on aqueous-phase solubility of polycyclic aromatic hydrocarbons from soil

The influence of anaerobic conditions on aqueous-phase polycyclic aromatic hydrocarbon (PAH) bioavailability was investigated in laboratory microcosms. Highly aged (>70 years), PAH-contaminated soil was incubated under anaerobic conditions by using various anaerobic headspaces, anaerobic headspaces with an oxygen-scavenging complex (titanium(III) citrate) in the aqueous phase, or anaerobic headspaces with electron-acceptor amendments in the aqueous phase. Incubation of soil solely under anaerobic conditions resulted in increased aqueous concentrations of all PAHs tested (fluoranthene, pyrene, benz[a]anthracene, and benzo[a]pyrene). Benz[a]anthracene and benzo[a]pyrene extractable concentrations were above aqueous solubility, by as much as an order of magnitude for the latter. The degree of solubility increase observed was a function of molecular weight of the PAH regardless of initial soil concentration, suggesting formation of stable PAH-soluble organic matter associations. The soil samples incubated aerobically for 90 d before imposition of anaerobic conditions did not release PAHs to the aqueous phase. Methanogenic organisms and sulfate-reducing bacteria were seen to have the most significant effect on increases in aqueous-phase PAHs. Polycyclic aromatic hydrocarbons made more soluble under anaerobic conditions was available to be degraded or transformed under aerobic conditions.

Enhancement of urinary elimination of 3-bromobenzanthrone metabolites by oral supplementation of ascorbic acid in guinea pigs

OBJECTIVE

3-Bromobenzanthrone (3-BBA), an anthraquinone intermediate dye, is extensively used in textile industry. Since, our prior studies have shown that 3-BBA caused significant depletion of ascorbic acid (AsA) levels, the effect of exogenous supplementation of AsA on the urinary elimination of 3-BBA metabolites was investigated.

METHOD

Guinea pigs were treated with single oral dose of 3-BBA (50 mg/kg b. wt.) in groundnut oil while another group was treated with single oral dose of 3-BBA (50 mg/kg b. wt.) along with 3 day prior and post oral supplementation of AsA. Control groups were either treated with groundnut oil or AsA alone. Urine from individual animals was collected, extracted and analysed on HPTLC.

RESULTS

The highest elimination of 3-BBA (75 microg) was found to be in 0-24 h urine fraction which decreased to 18 microg and 5 microg in the two subsequent 24 hourly fractions of urine. Exogenous supplementation of AsA increased the total urinary elimination of 3-BBA by almost 77%. A total of 10 fluorescent metabolites excluding the parent compound were eliminated in the urine of guinea pigs treated with 3-BBA. Densitometric scanning of chromatogram showed different peaks at Rf 0.18, 0.22, 0.27, 0.34, 0.40, 0.48, 0.56, 0.66, 0.72, 0.80, and 0.95 which were eliminated and marked as urinary metabolite 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11 respectively. AsA not only significantly enhanced the elimination of 3-BBA metabolites but also modified the pattern of metabolites drastically in 0-6 h, 6-24 h and 24-48 h urine fractions.

CONCLUSION

These results indicate that AsA may be useful in protecting the toxicity of 3-BBA by fascilitating the urinary metabolite(s) excretion of 3-BBA.

Mutagenic activity and quantification of nitroarenes in surface soil in the Kinki region of Japan

To clarify the mutagenic potential of surface soil in the Kinki region of Japan, particularly in Osaka and neighboring cities, 62 surface soil samples were collected and their organic extracts were examined by the Ames/Salmonella assay. All of the samples were mutagenic toward TA98 in both the presence and absence of a mammalian metabolic activation system (S9 mix). While all of the samples showed mutagenicity toward TA100 with S9 mix, only 45/62 (73%) were mutagenic without S9 mix. Fifty (81%) of the samples showed higher activity toward TA98 than TA100. The mean values of the mutagenicities of soil samples collected in Osaka prefecture (n=35) toward TA98 with and without S9 mix were 2315 and 1630 revertants per gram of soil, respectively, and these were 2.9 and 2.6 times as high as the values for samples from other prefectures (n=27), respectively. Three dinitropyrene (DNP) isomers, i.e. 1,3-, 1,6- and 1,8-DNP, and 3-nitrobenzanthrone (NBA) in the surface soil samples were quantified by fluorometric detection of the corresponding amino compounds, i.e. diaminopyrene isomers and 3-aminobenzanthrone, using high-performance liquid chromatography (HPLC). The three DNP isomers were detected in all of the soil samples (n=26) that were mainly collected in Osaka prefecture, and the amounts of 1,3-, 1,6- and 1,8-DNP were 6-1526, 11-1772 and 10-2092pg/g of soil, respectively. The contribution ratios of 1,3-, 1,6- and 1,8-DNP to the mutagenicity of soil extracts toward TA98 without S9 mix were 0.2-12, 0.3-12 and 0.5-27%, respectively. The amount of 3-NBA in soil samples (n=8) was 144-1158pg/g of soil, and the contribution ratio of 3-NBA to the mutagenicity of soil extracts was 2-38%. These results suggest that the surface soils in the Kinki region were highly polluted with mutagens and the pollution levels in Osaka prefecture were higher than those in other areas. DNP isomers and 3-NBA may be major mutagens that contaminate surface soil in this region.

Determination of 3-nitrobenzanthrone in surface soil by normal-phase high-performance liquid chromatography with fluorescence detection

A sensitive method for determining 3-nitrobenzanthrone in surface soil was developed. 3-Nitrobenzanthrone was reduced to 3-aminobenzanthrone by refluxing at 60 degrees C with hydrazine and Raney nickel for 20 min, and 3-aminobenzanthrone was determined by normal-phase high-performance liquid chromatography (HPLC) with fluorescence detection. We used a cyanopropyl stationary phase and an n-hexane-ethyl acetate (3:1, v/v) mobile phase, since 3-aminobenzanthrone exhibits fluorescence in a low-polarity solvent such as n-hexane or ethyl acetate, but not in a polar solvent such as water or methanol. The calibration graph showed good linearity (r2>0.9999) in the range of 0.002-2 ng, and the detection limit was 0.002 ng (S/N=3). 3-Nitrobenzanthrone in extracts from surface soil collected in the Chubu area (central area) of Japan was determined after clean-up using silica gel chromatography and high-performance liquid chromatography on a pyrenylethyl stationary phase. The concentration of 3-nitrobenzanthrone in surface soil was determined in the range of 1.2-1020 pg/g soil.

Determination of mutagenic 3-nitrobenzanthrone in diesel exhaust particulate matter by three-dimensional high-performance liquid chromatography

Mutagenic 3-nitrobenzanthrone was determined in diesel exhaust particulate matter by three-dimensional high-performance liquid chromatography. Nitrophenylethyl, C18 and pyrenylethyl stationary phases were used as the first, second and third dimensions, respectively. Methanol was used as a mobile phase for the first and second dimensions, and dichloromethane was used for the third. Each column was coupled by a 6-port valve with a concentrator column. Effluent from the third dimensional column was detected by a photodiode array detector. The calibration graph showed good linearity in the range of 1-1000 ng ml(-1), and the detection limit (S/N = 3) was 1 ng ml(-1) 3-Nitrobenzanthrone could be detected within 45 min without the requirement of a clean-up procedure. 3-Nitrobenzanthrone in diesel exhaust particulate matter was detected in the range of 27-56 pg mg(-1) extract (n = 3).

Analysis of agricultural commodities and foods for Alternaria mycotoxins

Fungi of the genus Alternaria are parasitic on plants and other organic materials. A. alternata is a frequently occurring species of particular interest because it produces a number of mycotoxins, including alternariol (AOH), alternariol monomethyl ether (AME), altenuene (ALT), altertoxins I, II, and III (ATX-I, -II, and -III), and L-tenuazonic acid (TeA). Cleanup procedures of analytical methods for foods and foodstuffs include solvent partition, generally used for TeA, and solid-phase extraction columns for AOH, AME, and ATX-I. These Alternaria mycotoxins have been determined by TLC, GC, and more usually LC, mainly with ultraviolet detection, although fluorescence and electrochemical detection have also been used for Alternaria toxins other than TeA. A Zn2+ salt is usually added to the LC mobile phase for TeA. Recently, atmospheric pressure chemical ionization and electrospray LC/MS and LC-MS/MS have been applied to the determination and confirmation of AOH and AME in apple juice and other fruit beverages at sub ng/mL levels. Natural occurrences of AOH, AME, and in some cases other Alternaria toxins have been reported in various fruits, including tomatoes, olives, mandarins, melons, peppers, apples, and raspberries. They have been found also in processed fruit products such as apple juice, other fruit beverages and tomato products, wheat and other grains, sunflower seeds, oilseed rape meal, and pecans.

Assessment of exposure to polycyclic aromatic hydrocarbons in police in Florence, Italy, through personal air sampling and biological monitoring of the urinary metabolite 1-hydroxypyrene

In this study, the authors evaluated exposure to airborne polycyclic aromatic hydrocarbons (PAHs) in workers exposed to exhaust gas from cars, and they assessed the efficiency of urinary 1-hydroxypyrene as an indicator of exposure to pyrene and PAHs. The authors selected 2 groups of police who worked in 2 areas in the city of Florence: 1 group was highly exposed to high-density traffic emissions during the winter and summer of 1997, and the 2nd group experienced low exposure to traffic emissions during the same period. Ambient monitoring was achieved with personal sampling of airborne PAHs during each workshift. Eight hydrocarbons were used as indicators of pollution caused by PAHs (e.g., pyrene, benzo[a]pyrene, benzo[a]anthracene, dibenzo[a,h]anthracene). Biological monitoring was performed through dosing of 1-hydroxypyrene (pyrene metabolite) in urine samples taken at the end of each workshift. The ambient monitoring revealed that PAH concentrations were influenced by both season of sampling and varying intensities of traffic in the different areas. The median concentration of benzo[a]pyrene in winter was twice as high in the high-density traffic area as in the low-density traffic area (i.e., 4.1 ng/m3 versus 1.8 ng/m3). In summer, the high-density traffic area experienced benzo[a]pyrene concentrations that were 6 times higher than in the low-density traffic area (i.e., 1.2 ng/m3 versus 0.2 ng/m3). Benzo[a]pyrene was also correlated highly (r(s) = .92, p < .0001) with the mixture of total PAHs analyzed, thus confirming its function as a good indicator of exposure to PAHs in an urban environment. Levels of urinary 1-hydroxypyrene appeared to be generally influenced by the intensity of traffic, especially during the winter (i.e., median value in winter was 199.2 ng/gm creatinine in the high-density traffic area and 120.5 ng/gm creatinine in the low-density traffic area). An analysis of the general data revealed that 1-hydroxypyrene was, to some degree, related to pyrene, benzo[a]pyrene, and airborne total PAHs, whereas analysis of separate data for the area and the season revealed an emergence of a closer correlation during the winter in the high-traffic area. Therefore, 1 -hydroxypyrene can be considered a good biological indicator of exposure to airborne PAHs in the urban environment, especially in winter and in high-density traffic areas.

Benzo(a)pyrene, benzo(a)anthracene, and dibenzo(a,h)anthracene emissions from coal and waste tire energy generation at atmospheric fluidized bed combustion (AFBC)

The main aim of this work was the analyzing of the release to the atmosphere of benzo[a]pyrene (BaP), dibenzo(a,h)anthracene (D(a,h)A), and benzo[a]anthracene (BaA), three of the most carcinogenic PAHs listed by US-EPA as priority pollutants, emitted from combustion at the last generation reactors used nowadays in power generation, fluidized bed reactors, trying to establish their incidence when waste materials are used as "new fuels". BaP, D(a,h)A, and BaA emissions, once collected in the sampling system, have been analyzed by fluorescence spectroscopy in the synchronous mode (FS) after extraction by ultrasonic bath with dimethylformamide (DMF) as solvent. Concerning to the combustion variables influence, the conclusion reached was that, in coal combustion, the lowest emissions of BaP are generated at percentages of excess oxygen of 20%, at flows corresponding to good fluidization conditions, 860 L/h (double of the minimum fluidization velocity) and temperatures out of 850 degrees C; the lowest emission of D(a,h)A are emitted at 20% excess oxygen, 900 L/h and out of 750 degrees C, and the lowest emission of BaA are generated at 20% excess oxygen, 860 L/h and out of the range 750-850 degrees C. Regarding tire as nonfossil fuel, higher emissions of BaP, BaA, and D(a,h)A are detected in comparison to coal combustion. In coal-tire blend, the BaP, BaA, and D(a,h)A emissions are more similar to the values obtained in coal combustion and not intermediate values as it could be expected by the blend composition.

Dermal exposure assessment of polycyclic aromatic hydrocarbons: in vitro percutaneous penetration from coal dust

To understand the dermal uptake of chemicals bound to soil and dust, information on the neat substance is helpful but does not seem sufficient. Because of its content of polycyclic aromatic hydrocarbons (PAHs) coal is suspected to be carcinogenic. However, experimental carcinogenity studies on coal dust never succeeded in demonstrating a higher incidence of cancer in treated animals. The aim of the study was to assess dermal penetration through human skin of PAHs from coal dust. A sample of coal dust was grinded and sieved, using the particle size of < 30 microm. An in vitro static diffusion cell system validated by in vitrolin vivo comparison has been used to study dermal penetration through human skin of PAHs from coal dust compared with their percutaneous absorption as pure compounds. No percutaneous penetration of PAHs was observed in the cells where coal dust was applied, while dermal penetration was demonstrated for PAHs applied in an acetone solution. Results agree with the literature that PAHs are poorly absorbed through the skin from solids. Dermal risk assessment of PAHs should take into account not only the degree and the extent of skin contamination, but also their bioavailability, which is heavily influenced by the physico-chemical characteristics of the matrix.

Error propagation as a factor in selection of measurement intervals for the determination of polycyclic aromatic hydrocarbons by second-derivative spectrofluorimetry

The most suitable wavelength intervals were selected for the determination of 4 polycyclic aromatic hydrocarbons (PAHs; benzo[g,h,i]perylene, dibenzo[a,h]anthracene, pyrene, and triphenylene) in very complex mixtures of 11 PAHs: anthracene, benz[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[g,h,i]perylene, benzo[k]fluoranthene, chrysene, dibenz[a,h]anthracene, phenanthrene, pyrene, and triphenylene. The multiple linear regression algorithm was applied to measurements made in several wavelength intervals previously selected on the basis of sensitivity and minimum number of interfering compounds. Of the different models obtained, those displaying minimum error propagation in the analytical result were selected. By applying the models proposed in this study, we precisely and accurately determined benzo[g,h,i]perylene, dibenz[a,h]anthracene, pyrene, and triphenylene in complex mixtures--a feat that could not be achieved by the use of constant-wavelength spectrofluorimetry in combination with second-derivative techniques.

Application of partial least-squares calibration to phosphorimetric data for determination of polycyclic aromatic hydrocarbons in spiked environmental samples

A partial least-squares calibration method is proposed, for the first time, for phosphorescence signals. The proposed method is based on the determination of phenanthrene, fluoranthene, and benz[a]anthracene by room temperature phosphorimetry, using microemulsion solutions. The emission and first-derivative emission spectra of the ternary mixtures were tested to perform the calibration matrix. Improved recoveries were found for the prior differentiation step in the analysis of ternary mixtures of these polycyclic aromatic hydrocarbons in road dust samples. The proposed method yielded recoveries ranging from 93.2 to 115.3%, with relative standard deviations of < 6.8%.

High-performance liquid chromatographic method with fluorescence detection for the determination of 3-hydroxybenzo[a]pyrene and 3-hydroxybenz[a]anthracene in the urine of polycyclic aromatic hydrocarbon-exposed workers

The described high-performance liquid chromatographic method with fluorescence detection (HPLC-FD) permits the simultaneous determination of 3-hydroxybenzo[a]pyrene and 3-hydroxybenz[a]anthracene as the most important metabolites of the carcinogenic polycyclic aromatic hydrocarbons (PAHs) benzo[a]pyrene and benz[a]anthracene in human urine. After enzymatic hydrolysis, to release the conjugated metabolites, the analytes are separated from the matrix by means of a liquid-solid extraction step which is followed by a coupled column HPLC procedure using an enriching precolumn consisting of silica modified with copper phthalocyanine. This special precolumn selectively adsorbs PAHs with at least three condensed rings and thus separates them from the urine matrix. The quantitative analysis was carried out using a switchable fluorescence detector. The detection limits were 6 ng/l urine (3-hydroxybenzo[a]pyrene) and 8 ng/l urine (3-hydroxybenz[a]anthracene). The relative standard deviations of the within-series imprecision ranged between 4.0% and 9.0%. The between-day imprecision was 7.7% (3-hydroxybenz[a]anthracene) and 12.9% (3-hydroxybenzo[a]pyrene). The recovery rates ranged between 102% and 124%. Using this analytical method we determined PAH metabolites in post shift urine samples from 19 workers engaged in the production of fire-proof materials. The urinary concentrations ranged from 3 to 198 ng 3-hydroxybenzo[a]pyrene per g creatinine and from 15 to 1871 ng 3-hydroxybenz[a]anthracene per g creatinine.

Mutagenic substances in pyrolysate obtained by burning polyvinylchloride-product at 1000 degrees C

In order to detect possible mutagenic substances in pyrolysate obtained by burning polyvinyl chloride product (PVC-P) at approximately 1000 degrees C, mutagenicity of rough extracts obtained by extraction with various solvents for the products was investigated by means of reversion mutation assay using Salmonella typhimurium TA98 and TA100 with or without microsomal metabolic activation (S9 mix). Strong mutagenicity in TA98 without S9 mix was observed in acetone-extract of PVC-P. The extract was fractionated into acidic, neutral and basic by liquid-liquid distribution and the mutagenicity in TA98 without S9 mix was found in the neutral fraction. Identification of mutagenic substances in the neutral fraction from acetone extract, which showed the strongest mutagenicity, was attempted by means of thin layer chromatography and capillary gas chromatography. The results suggest that mutagenic substances from pyrolysate of PVC-P are benzanthrone and an isomer of benzo(c)cinnoline. The results also suggest that burning wastes containing plastic products is not always safe even if at 1000 degrees C and further research on the problem is necessary.

Food heating and the formation of heterocyclic aromatic amine and polycyclic aromatic hydrocarbon mutagens/carcinogens

Heterocyclic aromatic amines (HAA) and polycyclic aromatic hydrocarbons (PAH) are mutagens and animal carcinogens sometimes formed when foods are heated or processed. Determining their role in cancer etiology depends on comparing human exposures and determining any significant dose-related effects. Chemical analysis of foods shows that flame-grilling can form both PAH and HAA, and that frying forms predominantly HAA. With detection limits of about 0.1 ng/g, amounts found in commercially processed or restaurant foods range from 0.1 to 14 ng/g for HAA, and levels of PAH up to 1 ng/g in a liquid smoke flavoring. Laboratory fried samples have greater amounts of PAH, up to 38 ng/g in hamburgers, and high levels of HAA, over 300 ng/g, are measured in grilled chicken breast. Understanding the processing conditions that form PAH and HAA can lead to methods to greatly reduce their occurrence in processed foods.

Mycotoxins of Alternaria alternata produced on ceiling tiles

The production of mycotoxins by Alternaria alternata in cellulosic ceiling tiles was examined with thin-layer chromatography and high-performance liquid chromatography procedures. Alternariol and alternariol monomethyl ether were found in ceiling tile extracts, whereas extracts of control rice cultures of all three isolates produced these mycotoxins plus altenuene and altertoxin I. Extensive fungal growth and mycotoxin production occurred in the ceiling tiles at relative humidities of 84-89% and 97%.

Infrared spectroscopy of matrix-isolated polycyclic aromatic hydrocarbon cations. 4. The tetracyclic PAH isomers chrysene and 1,2-benzanthracene

The mid-infrared spectra of the polycyclic aromatic hydrocarbon (PAH) cations of the tetracyclic isomers chrysene (C18H12+) and 1,2-benzanthracene (C18H12+) are presented. As with previous PAH cations studied to date, the CC stretching and CH in-plane bending mode absorptions are about an order of magnitude stronger than the aromatic CH out-of-plane bending absorptions and nearly 2 orders of magnitude more intense than the corresponding bands in the neutral molecule. The CH bands arising from the out-of-plane bends in the cation are slightly weaker than the corresponding bands in the neutral species. The strongest cation bands of these species fall between 1300 and 1330 cm-1, close to the peak of the most intense interstellar emission feature in HII regions and reflection nebulae. A strong PAH cation band at slightly higher frequency than 1300 cm-1 may be associated with an asymmetric CC stretching vibration involving rings adjacent to the kink in the chain of aromatic rings.

Gas chromatography-mass spectrometry of Alternaria mycotoxins

Heptafluorobutyrate (HFB) derivatives have not previously been used for GC of Alternaria mycotoxins. Capillary (0.5 micron film) GC-mass spectrometry (MS) showed that full and partial derivatives of alternariol (AOH), alternariol monomethyl ether (AME) and altenuene (ALT); a structurally uncharacterized derivative of altertoxin I (ALTX-I); and a tris-HFB derivative of tenuazonic acid (TA) were formed with heptafluorobutyric anhydride and a basic catalyst. Full and partial trimethylsilyl (TMS) ethers of these mycotoxins were formed with Tri-Sil TBT. Apple juice extracts caused increased response in GC-MS of AOH bis-HFB and bis-TMS derivatives. Natural occurrence of AOH in apple juice has been demonstrated.

Analysis of 7-methylbenz[a]anthracene-DNA adducts formed in SENCAR mouse epidermis by 32P-postlabeling

The present study has analysed the DNA adducts formed in SENCAR mouse epidermis following topical application of 7-methylbenz[a]anthracene (7-MBA). Mice were treated with 400 nmol of 7-MBA, which represents an initiating dose of this hydrocarbon for SENCAR mice. DNA adducts were analysed 24 h after topical application of the hydrocarbon by 32P-postlabeling coupled with either HPLC analysis or an improved TLC procedure giving better resolution of DNA adducts through the use of a D6 solvent [isopropanol:4N NH4OH (1:1)] following D5. Twenty-four hours after topical application of 400 nmol 7-MBA, the level of total covalent binding was 0.37 +/- 0.07 pmol/mg DNA as determined by 32P-postlabeling. This level of binding correlated well with the relative tumor initiating activity of this hydrocarbon compared to 7,12-dimethylbenz[a]anthracene (6.4 +/- 0.01 pmol/mg DNA) and dibenz[a,j]anthracene (0.03 +/- 0.01 pmol/mg DNA). Analysis of the 32P-labeled 3',5'-diphosphodeoxyribonucleosides by HPLC and TLC revealed the presence of deoxyguanosine (dGuo) and deoxyadenosine (dAdo) adducts formed from both the anti- and syn-bay-region diol-epoxides of 7-MBA (anti- and syn-7-MBADEs). The major DNA adduct derived from 7-MBA in mouse epidermis was tentatively identified as (+) anti-7-MBADE-trans-N2-dGuo. In addition, a minor dGuo adduct derived from the bay-region syn-diol-epoxide of 7-MBA was detected as well as a minor dAdo adduct from this diol-epoxide. Another minor dAdo adduct was also detectably present which arose from either the anti- or syn-diol epoxide. Furthermore, several unidentified DNA adducts were present in both HPLC and TLC chromatograms of DNA samples from 7-MBA-treated mice. These results are discussed in terms of the role of specific 7-MBA-DNA adducts in tumor initiation by this hydrocarbon.

A cohort study with children living in an air-polluted region--a model for public health

Regions with heavy industry are in many ways regions of crisis. The health of the population is primarily affected by the different air pollutants. Dust, with all its organic (dioxins and furans) and inorganic (heavy metals) contents, makes up the greatest part of the air-borne pollutants. The influence on health of environmental pollution was ascertained through the determination of different parameters (functional methods and determination of physiological parameters). This influence could be observed in children over a period of 8 years with regular investigations (e.g. determination of pulmonary function by spirometry and immunological parameters). Besides this exogenous load the persons are exposed to other environmental stresses-shift work, unemployment, alcoholism and divorce-which have a particular influence on the attitude and the upbringing of the children. Sixty per cent of the children in this polluted region ate no breakfast in the morning. Consequently it could be shown that the blood sugar in 70% of the children was below 70 mg/dl. Additionally, a relatively high amount of COHb (2.5% to 3%), and an increased concentration of serum IgE (47% of children with a concentration over 100 IU/ml), could be detected. Through a change in the environmental awareness of the children and their consequent influence, an effort should be made to achieve a positive effect on the health of the whole population. The children were given a chance to participate in various sports for the whole day during a week in the mountains at 1200 m. The teachers exercised with the children for at least 8 h per day. Besides gymnastics the program consisted of downhill and cross-country skiing. In addition, the children were offered a balanced and natural diet and they were instructed accordingly. This week of activity led to a clear reduction of the concentration of COHb, but to a far less clear improvement in the concentration of blood sugar and the pulmonary function.