Biomonitoring of polycyclic aromatic hydrocarbons in Brazilian pregnant women: Urinary levels and health risk assessment.

Over the years, humans have been continuously exposed to several compounds directly generated by industrial processes and/or present in consumed products. Polycyclic aromatic hydrocarbons (PAHs) are legacy pollutants ubiquitous in the environment and represent the main chemical pollutants in urban areas. Worldwide, studies that aim to understand the impacts of exposure to these chemicals have gained increasing prominence due to their potential toxicity profile, mainly concerning genotoxicity and carcinogenicity. Human biomonitoring (HB) is an analytical approach to monitoring population exposure to chemicals; however, these studies are still limited in Brazil. Thus, this work aimed to evaluate the exposure of Brazilian pregnant women to PAHs through HB studies. Besides, the risk characterization of this exposure was performed. For this purpose, urine samples from 358 Brazilian pregnant women were used to evaluate 11 hydroxylated metabolites of PAHs employing gas chromatography coupled to mass spectrometry. The 1OH-naphthol and 2OH-naphthol were detected in 100% of the samples and showed high levels, corresponding to 16.99 and 3.62 µg/g of creatinine, respectively. 2OH-fluorene (8.12 µg/g of creatinine) and 9OH-fluorene (1.26 µg/g of creatinine) were detected in 91% and 66% of the samples, respectively. Benzo(a)pyrene (BaP) metabolites were detected in more than 50% of the samples (0.58-1.26 µg/g of creatinine). A hazard index of 1.4 and a carcinogenic risk above 10-4 were found for BaP metabolites in the risk characterization. Therefore, our findings may indicate that exposure to PAHs poses a potential risk to pregnant women's health and a high probability of carcinogenic risk due to their exposure to BaP. Finally, this work shows the need for more in-depth studies to determine the sources of exposure and the implementation of health protection measures regarding the exposure of the Brazilian population to PAHs.

Comparative assessment of soil microbial community in crude oil contaminated sites.

Petroleum refineries generate oily sludge that contains hazardous polycyclic aromatic hydrocarbons (PAH), and hence, its proper disposal is of foremost concern. Analysis of the physicochemical properties and functions of indigenous microbes of the contaminated sites are essential in deciding the strategy for bioremediation. This study analyses both parameters at two geographically distant sites, with different crude oil sources, and compares the metabolic capability of soil bacteria with reference to different contamination sources and the age of the contaminated site. The results indicate that organic carbon and total nitrogen derived from petroleum hydrocarbon negatively affect microbial diversity. Contamination levels vary widely on site, with levels of PAHs ranging from 5.04 to 1.66 × 103 µg kg-1 and 6.20 to 5.64 × 103 µg kg-1 in Assam and Gujarat sites respectively, covering a higher proportion of low molecular weight (LMW) PAHs (fluorene, phenanthrene, pyrene, and anthracene). Functional diversity values were observed to be positively correlated (p < 0.05) with acenaphthylene, fluorene, anthracene, and phenanthrene. Microbial diversity was the highest in fresh oily sludge which decreased upon storage, indicating that immediate bioremediation, soon after its generation, would be beneficial. Improvement in the bio-accessibility of hydrocarbon compounds by the treatment of biosurfactant produced by a (soil isolate/isolate) was demonstrated., with respect to substrate utilization.

Seasonal assessment of the distribution, source apportionment, and risk of water-contaminated polycyclic aromatic hydrocarbons (PAHs).

The research aims to evaluate the seasonal differences in the distribution, source, and risks of water-contaminated PAHs. The PAHs were extracted by the liquid-liquid method and analyzed with GC-MS, and a total of eight PAHs were detected. There was a percentage increase in the average concentration of the PAHs from the wet to the dry season in the range of 20 (Anthracene)-350 (Pyrene)%. Total PAHs (∑PAHs) range from 0.31 to 1.23 mg/l in the wet period and from 0.42 to 1.96 mg/l in the dry period. The distribution of the average PAHs in mg/l showed that Fluoranthene ≤ Pyrene < Acenaphthene < Fluorene < Phenanthrene < Acenaphthylene < Anthracene < Naphthalene in wet period and while Fluoranthene < Acenaphthene < Pyrene < Fluorene < Phenanthrene < Acenaphthylene < Anthracene < Naphthalene in the dry period. The children were exposed to non-carcinogenic risk through non-dietary ingestion due to the accumulative effect (HI) of the PAHs in the dry period. Furthermore, the naphthalene was responsible for ecological and carcinogenic risk in the wet period, while the fluorene, phenanthrene, and anthracene were responsible for ecological and carcinogenic risk in the dry period. However, while adults and children are both susceptible to carcinogenic risk through the oral channel during the dry period, only children are susceptible to non-carcinogenic risk through this pathway. The multivariate statistical analysis revealed the influence of physicochemical parameters on the detected PAHs and also showed the PAHs' sources to be mainly combustion, pyrolysis, and vehicular emission.

Exposure assessment of polycyclic aromatic hydrocarbons in refined coal tar sealant applications.

BACKGROUND: Refined coal tar sealant (RCTS) emulsions are used to seal the surface of asphalt pavement. Nine of the 22 polycyclic aromatic hydrocarbons (PAHs) evaluated in this study are classified as known, probable, or possible human carcinogens. Exposure assessment research for RCTS workers has not been published previously. OBJECTIVES: The overall objective of this study was to develop a representative occupational exposure assessment of PAH exposure for RCTS workers based on worksite surveys. The specific aims were to: 1) quantify full-shift airborne occupational exposures to PAHs among RCTS workers; 2) quantify workers' dermal exposures to PAHs; 3) quantify biomarkers of PAH exposure in workers' urine; 4) identify specific job titles associated with RCTS exposure; and 5) apply these results to a biological exposure index to assess risk of potential genotoxicity from occupational exposures. METHODS: A total of twenty-one RCTS workers were recruited from three companies. Personal and area air samples were collected using a modification of NIOSH Method 5515. Dermal exposure was assessed by hand and neck wipes before and after shifts. Twenty-two PAHs were quantified via gas chromatography-mass spectrometry selected ion monitoring. Internal dose was estimated by quantifying select PAH metabolites in pre- and post-shift urine samples using on-line solid phase extraction-high performance liquid chromatography-tandem mass spectrometry. RESULTS: PAH levels in the worker breathing zones were highest for naphthalene, acenaphthene, and phenanthrene, with geometric means of 52.1, 11.4, and 9.8 µg/m3, respectively. Hand wipe levels of phenanthrene, fluoranthene and pyrene were the highest among the 22 PAHs with geometric means of 7.9, 7.7, and 5.5 µg/cm2, respectively. Urinary PAH biomarkers for naphthalene, fluorene, phenanthrene, and pyrene were detected in all workers and were higher for post-shift samples than those collected pre-shift. Urinary concentrations of the metabolite 1-hydroxypyrene were greater than the American Conference of Governmental Industrial Hygienists (ACGIH) Biological Exposure Index (BEI) for this metabolite in 89 percent of post-shift samples collected on the final day of the work week or field survey. Statistically significances were found between concentrations of fluorene, naphthalene, and phenanthrene in the breathing zone of workers and their corresponding urinary PAH biomarkers. Workers were placed in two work place exposure groups: applicators and non-applicators. Applicators had higher total PAH concentrations in personal breathing zone (PBZ) air samples than non-applicators and were more likely to have post-shift hand wipe concentrations significantly higher than pre-shift concentrations. Concentrations of post-shift urinary biomarkers were higher, albeit not significantly, for applicators than non-applicators. CONCLUSIONS: The exposure results from RCTS worker samples cannot be explained by proximal factors such as nearby restaurants or construction. Air and skin concentration levels were substantially higher for RCTS workers than previously published levels among asphalt workers for all PAHs. PAH profiles on skin wipes were more consistent with RCTS sealant product than air samples. Last day post-shift urinary concentrations of 1-hydroxypyrene greatly exceeded the ACGIH BEI benchmark of 2.5 µg/L in 25 of 26 samples, which suggests occupational exposure and risk of genotoxicity. When pyrene and benzo[a]pyrene were both detected, concentration ratios from personal exposure samples were used to calculate the adjusted BEI. Concentrations of 1-hydroxypyrene exceeded the adjusted BEIs for air, hand wipes, and neck wipes in most cases. These results indicate the need to increase safety controls and exposure mitigation for RCTS workers.

Occupational exposure and markers of genetic damage, systemic inflammation and lung function: a Danish cross-sectional study among air force personnel.

Air force ground crew personnel are potentially exposed to fuels and lubricants, as raw materials, vapours and combustion exhaust emissions, during operation and maintenance of aircrafts. This study investigated exposure levels and biomarkers of effects for employees at a Danish air force military base. We enrolled self-reported healthy and non-smoking employees (n = 79) and grouped them by exposure based on job function, considered to be potentially exposed (aircraft engineers, crew chiefs, fuel operators and munition specialists) or as reference group with minimal occupational exposure (avionics and office workers). We measured exposure levels to polycyclic aromatic hydrocarbons (PAHs) and organophosphate esters (OPEs) by silicone bands and skin wipes (PAHs only) as well as urinary excretion of PAH metabolites (OH-PAHs). Additionally, we assessed exposure levels of ultrafine particles (UFPs) in the breathing zone for specific job functions. As biomarkers of effect, we assessed lung function, plasma levels of acute phase inflammatory markers, and genetic damage levels in peripheral blood cells. Exposure levels of total PAHs, OPEs and OH-PAHs did not differ between exposure groups or job functions, with low correlations between PAHs in different matrices. Among the measured job functions, the UFP levels were higher for the crew chiefs. The exposure level of the PAH fluorene was significantly higher for the exposed group than the reference group (15.9 ± 23.7 ng/g per 24 h vs 5.28 ± 7.87 ng/g per 24 h, p = 0.007), as was the OPE triphenyl phosphate (305 ± 606 vs 19.7 ± 33.8 ng/g per 24 h, p = 0.011). The OPE tris(1,3-dichlor-2-propyl)phosphate had a higher mean in the exposed group (60.7 ± 135 ng/g per 24 h) compared to the reference group (8.89 ± 15.7 ng/g per 24 h) but did not reach significance. No evidence of effects for biomarkers of systemic inflammation, genetic damage or lung function was found. Overall, our biomonitoring study show limited evidence of occupational exposure of air force ground crew personnel to UFPs, PAHs and OPEs. Furthermore, the OH-PAHs and the assessed biomarkers of early biological effects did not differ between exposed and reference groups.

Biodegradation of fluorene by the newly isolated marine-derived fungus, Mucor irregularis strain bpo1 using response surface methodology.

Fluorene, a low molecular weight polycyclic aromatic hydrocarbon (PAH), is of immense environmental interest because of its carcinogenicity, teratogenicity, mutagenicity, toxicity and persistence to microbial degradation. Existentially, there is paucity of information on PAH degradation by fungi isolated from marine environment. Therefore, this study investigated fluorene degradation efficiency of marine derived filamentous fungus, Mucor irregularis strain bpo1 (GenBank Accession Number: MK373020). Response Surface Methodology (RSM) using Box-Behnken Design (BBD) was successfully deployed in the optimization of process parameters (pH-7, temperature-32.5 °C, substrate concentration-100 mg L-1 and dry weight-2 g) resulting in 81.50% fluorene degradation on 5th day. The design and regression model were found to be statistically significant, adequate and appropriate with p < 0.0001, F value= 202.39, and predicted coefficient of determination (R2 =0.9991). Optimization of the vital constituents of the mineral salt medium (MSM) used for the study using RSM-Central Composite Design (CCD) resulted in 79.80% fluorene degradation rate. Enhanced fluorene degradation efficiency (82.50%) was recorded when the optimized process variables were subjected to growth-linked validation experiments. The enzyme activities revealed 87%, 59% and 31% induction of laccase, manganese peroxidase and lignin peroxidase respectively. Four metabolites; 9H-fluoren-9-one, benzene-1,2-dicarboxylic acid, 2-hydroxybenzoic acid and phenol obtained after the experiment were characterized and confirmed with GC-MS analysis. The findings revealed the promising potentials of M. irregularis in PAH degradation and by extension green remediation technology.

Effects of smoke flavoring using different wood chips and barbecuing on the formation of polycyclic aromatic hydrocarbons and heterocyclic aromatic amines in salmon fillets.

Herein, the concentrations of food toxicants, polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatic amines (HAAs), in salmon fillets smoke flavored with different smoking wood chips (oak, apple, bourbon soaked oak, cherry and hickory) and barbecuing were determined. Benzo[a]anthracene (up to 0.24 ng/g) and chrysene (0.22 ng/g) were determined in the raw salmon fillets. While ∑PAH8 (benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[g,h,i]perylene, indeno[1,2,3-cd]pyrene) in the raw samples ranged between 0.44 and 0.46 ng/g, smoke flavoring increased the amount of ∑PAH8 and the amount varied between 0.47 and 0.73 ng/g. Salmon smoked flavored with bourbon soaked oak, cherry and hickory wood chips and barbecued showed significantly (P <0.05) lower contents of ∑PAH4 (benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[a]pyrene) and ∑PAH8 compared to non-smoke flavored barbecued samples. Additionally, smoke flavoring with apple, bourbon soaked oak, and cherry wood chips significantly (P <0.05) reduced the total HAA contents in barbecued salmon. A remarkable result was that the bourbon-soaked oak and cherry wood chips had inhibitory effects on both PAH and HAA contents. In sum, barbecued non-smoke flavored and smoke flavored salmon with different wood chips could be considered safe from the perspective of the detected amounts of PAHs and HAAs in salmon fillets.

Polycyclic aromatic hydrocarbons in traditionally smoked Slavonska kobasica.

The traditional smoking procedure, which is the use of open fire, can lead to the formation of PAHs in sausages. The aim of this paper was to assess the types and concentrations of 16 PAHs in 30 samples of Slavonska kobasica, a traditional smoked sausage. In general, some samples showed high values of anthracene and acenaphthylene. In one sample, acenaphthylene reached the value of 1050 µg/kg and in another 1491 µg/kg anthracene was measured. Cancerogenic benzo(a)pyrene content was little above the maximum limit of 5 µg/kg in four samples, but mainly remained below the limit of quantification. PAH4 (i.c. benzo(a)anthracene, chrysene, benzo(b)fluoranthene and benzo(a)pyrene) were above the maximum limit of 30 µg/kg in three samples. Generally, it can be noted from the results that samples with high PAH4 and benzo(a)pyrene concentrations also have high PAH16 concentrations.

Distribution, toxicity, and origins of polycyclic aromatic hydrocarbons in soils in Ulsan, South Korea.

This study was conducted to investigate the concentrations, distributions, toxicities, and sources of polycyclic aromatic hydrocarbons (PAHs) in the soils from different areas in Ulsan, South Korea. Samples were collected from 41 sites, including a waste treatment facilities area (WA), traffic facilities area (TA), child playground area (CA), industrial area (IA), railroad facilities area (RA), ore and iron scraps fields area (OA), and residential area (ReA). Ulsan was chosen for research area because it used to be an environmental hot spot in South Korea, and 16 PAHs in the US EPA priority pollutant list were selected. The concentration of total PAHs (t-PAHs) ranged from 61.7 to 12,421 µg/kg, and the average concentration of t-PAHs was 706.9 µg/kg. The distribution of PAHs by ring number indicated that the portion followed the order of 4 rings > 5 rings > 3 rings > 6 rings > 2 rings. According to PAH origin indices, LMW/HMW (low molecular weight 2-3 ring PAHs over high molecular weight 4-6-ring PAHs), phenanthrene/anthracene ratio and fluoranthene/pyrene ratio, benzo(g,h,i)perylene/indeno (1,2,3-c,d)pyrene ratio, vehicular emissions, and the combustion of fossil fuel were the sources of PAHs. The strong correlation (R2 = 0.995) between t-PAHs and total carcinogenic PAHs (t-PAHcarc) indicated that the concentration of t-PAHcarc increased in proportion with that of t-PAHs. The toxic equivalent concentrations (TEQs) of PAHs in the soils ranged from 44.0 to 1929.9 µg TEQ/kg. It is imperative to set regulatory levels for PAHs for periodic monitoring and rapid remediation action of contaminated soils, because there are no national standards in South Korea for 15 PAHs with the exception of benzo(a)pyrene.

Reduction of the polycyclic aromatic hydrocarbon levels in dried red peppers (Capsicum annuum L.) using heat pump-assisted drying.

Polycyclic aromatic hydrocarbons (PAHs) are primarily produced during the incomplete combustion of organic matter. PAHs are suspected endocrine disruptors and possible carcinogenic materials. The major sources of human exposure to PAHs are inhaled fumes and food. The aim of this study was to provide an alternative drying method to mitigate PAH formation in dried red peppers. We prepared dried red pepper samples using air-drying and heat pump-assisted drying methods, and measured the concentrations of four PAHs (PAH4), benzo[a] anthracene (B[a]A), chrysene (CHR), benzo[b]fluoranthene (B[b]F), and benzo[a]pyrene (B[a]P), in the resulting pepper samples. The PAH concentrations ranged from 3.61 to 18.0 µg/kg and from 2.22 to 8.35 µg/kg in the air-dried and heat pump-dried pepper samples, respectively. Overall, the results have shown that dried peppers contain PAH4, that the drying conditions for these contaminants should be optimized for mitigating the PAH formation in dried red peppers.

Polycyclic aromatic compounds in urban air and associated inhalation cancer risks: A case study targeting distinct source sectors.

Passive air sampling was conducted in Toronto and the Greater Toronto Area from 2016 to 2017 for 6 periods, in order to investigate ambient levels of polycyclic aromatic compounds (PACs) associated with different source types. The selected sampling sites (n = 8) cover geographical areas with varying source emissions including background, traffic, urban, industrial and residential sites. Passive air samples were analyzed for PACs which include PAHs, alkylated PAHs (alk-PAHs), dibenzothiophene and alkylated dibenzothiophenes (DBTs) and results for PAHs were used to calculate inhalation cancer risks using different approaches. The samples were also characterized for PAH derivatives including nitrated PAHs (NPAHs) and oxygenated PAHs (OPAHs). Concentrations of Σalk-PAHs and DBTs, which are known to be enriched in fossil fuels, as well as ΣNPAHs, were highest at a traffic site (MECP) located adjacent to the 18-lane Highway 401 that runs across Toronto. Except for an industrial site (HH/BU), PAC compositions were similar across the sampling sites with Σalk-PAHs being the most abundant class of PACs suggesting traffic emission was a major contributor to PACs in the atmosphere of Toronto. The industrial site exhibited a distinct chemical composition with ΣPAHs dominating over Σalk-PAHs and with elevated levels of fluoranthene, 9-nitroanthracene, and 9,10-anthraquinone, which likely reflects emissions from nearby industrial sources. MECP and HH/BU exhibited higher lifetime excess inhalation cancer risks indicating an association with traffic and industrial sources. The importance of the traffic sector as a source of PACs to ambient air is further supported by strong correlations of the ΣPAHs, Σalk-PAHs, DBTs, and ΣOPAHs with NOx. This study highlights the importance of traffic as an emission source of PACs to urban air and the relevance of PAC classes other than just unsubstituted PAHs that are important but currently not included in air quality guidelines or for assessing inhalation cancer risks.

Influence of emulsified biodiesel on the emission and health risk of polycyclic aromatic hydrocarbons in the vapor and particulate phases during engine combustion.

Biofuel is a renewable energy source for transportation. Given the toxicity associated with particulate polycyclic aromatic hydrocarbons (PAHs) is not fully understood, investigating the difference of adverse health risks posed between vapor and particulate PAH emissions from biodiesel-fueled engine combustion was the objective of this study. Three different fuel types, including typical diesel, emulsified diesel with a water fraction from 10 to 19% (v/v), and emulsified biodiesel with water (10%) and biofuel fractions from 10 to 40% (v/v), were studied. The fugacity model and risk assessment were conducted to predict the health risks when different fuels were used. In the results, the addition of water and biofuel elevated and reduced the total PAH emissions in the exhausts, respectively. After the emission, chrysene and benzo(a)anthracene were two dominant carcinogenic species in the environment. The excess cancer risk of the PAH emission significantly decreased (e.g., up to two orders of magnitude) while the emulsified biodiesel was applied, with limiting the formation of benzo(a)pyrene being the explanation. The PAH emissions with molecular weights ranging from 166 to 255 g/mol were significantly different between the vapor and particulate phases during the emulsified biodiesel combustion (p < 0.01). From the viewpoint of cancer risk, the contribution posed by the particulate PAHs was significantly greater than those by the vapor PAHs (e.g., from 54% (benzo(a)pyrene) to 76% (benzo(b)fluoranthene)). Benzo(a)pyrene and chrysene represent the species with the highest and lowest risks, respectively. The multi-ringed PAHs with four or five rings were more indicative of potential cancer risk posed by the PAHs associated with particulate matters during combustion of the emulsified biodiesel.

Identification of halogenated polycyclic aromatic hydrocarbons in biological samples from Alberta Oil-Sands Region.

Halogenated polycyclic aromatic hydrocarbons (HPAHs) were identified in biological samples from the Alberta Oil-Sands Region (AOSR) using gas chromatography coupled with high-resolution time-of-flight mass spectrometry (GC-HRTOF-MS) at a resolving power of 25,000. Knowledge of the electron ionization (EI) fragmentation behavior of individual HPAH isomers, achieved by injecting authentic standards in full-scan MS mode, was paramount in identifying a suite of HPAHs in samples from the AOSR. Confirmation of compounds in biological samples was based on the measured mass accuracy (±3 ppm) of 2 characteristic ions prominent in the EI mass spectra of each compound. Numerous compounds were detected in the high resolution total ion chromatogram in liver extracts of 4 biological species from the AOSR: river otter (Lontra Canadensis), northern pike (Esox lucius), lake whitefish (Coregonus clupeaformis) and snails (Gastropod sp.) many of which remain unidentified. Careful examination of the high-resolution accurate mass data suggests that dichloro-anthracene/phenanthrene, bromo-anthracene/phenanthrene and dibromo-fluorene were present in the biological samples. Lipid corrected concentrations of dichloro-PAHs were estimated to be 16.3 ±â€¯11.4 (n = 4) and 5.5 (n = 1) ng/g in lake whitefish and river otter, respectively. Concentrations of mono-bromo-PAHs were an order of magnitude greater in snails (170.5 ng/g) than in northern pike (12.5 ng/g) while concentrations of dibromo-PAHs were 4 times greater in snails than in northern pike. The detection of these compounds in biota implies that these compounds are bioaccumulative. The liver-based biomagnification factor of the dichloro-PAH congener in the river otter/lake whitefish feeding relationship is much smaller than 1 implying that this compound does not biomagnify.

Health risk assessment and source apportionment of polycyclic aromatic hydrocarbons associated with PM10 and road deposited dust in Ahvaz metropolis of Iran.

The objective of this study was to compare the characteristics of polycyclic aromatic hydrocarbons (PAHs) in PM10 and road dust samples, as well as to identify and quantify the contributions of each source profile using the positive matrix factorization (PMF) receptor model. Health risk assessment was carried out using toxic equivalency factors and incremental lifetime cancer risk (ILCR), which quantitatively estimate the exposure risk for age-specific groups. PM10 samples were collected on PTFE filters in the metropolitan area of Ahvaz. Road dust samples were also collected from all over the urban areas with different land uses. Total PAH concentrations in PM10 and road dust samples were 0.5-25.5 ng/m3 and 49.3-16,645 µg/kg, respectively. Pyrene was the highest PAH in the PM10 profile, whereas fluoranthene became the highest PAH in the road dust. Abundance of benzo[ghi]perylene at PM10 and road dust samples suggested a source indicator for traffic emissions. The results demonstrate that in 36.5% of samples, PM10 concentrations exceed the maximum concentration level recommended by EPA. A multiple linear regression model was used to estimate the influence of meteorological parameters (temperature, wind speed, and relative humidity) on buildup of PAHs. All of PAH species show higher concentrations during the cold and typical days rather than the dust event days and warm periods. PMF analysis showed that vehicular emissions (50.6%) and industrial activities (especially steel industries) (30.4%) were first two sources of PAHs bounded with PM10, followed by diesel emissions (11.6%) and air-soil exchange (7.4%). For road dust samples, three common sources were also identified: vehicular traffic (48%), industrial activities (42.3%), and petrogenic sources (9.7%), in line with that of diagnostic molecular ratios results. According to the results of health risk assessment model, the ILCR of exposure to PAHs associated with PM10 and road-deposited dust was higher than the guidelines of USEPA, indicating high carcinogenic risk.

Association between polycyclic aromatic hydrocarbons and osteoporosis: data from NHANES, 2005-2014.

The association between osteoporosis and polycyclic aromatic hydrocarbons was not clear. However, recent studies showed that both osteoporosis and polycyclic aromatic hydrocarbons were associated with reactive oxygen species. So we presumed that polycyclic aromatic hydrocarbons were associated with increased odds of osteoporosis. We found 3-hydroxyfluorene was associated with decreased odds of osteoporosis, while 2-hydroxyfluorene was associated with increased odds of osteoporosis. PURPOSE: Previous studies showed that polycyclic aromatic hydrocarbons were involved in the production of reactive oxygen species that played an important role in illness. Other studies demonstrated that the reactive oxygen species might play a role in occurrence of osteoporosis. However, the association between polycyclic aromatic hydrocarbons and osteoporosis was not clear. Therefore, we conducted a study to investigate the relationship between polycyclic aromatic hydrocarbons and osteoporosis. METHODS: A total of 3053 individuals aged 50 years or older were drawn from National Health and Nutritional Examination Survey, 2005-2014. Eight polycyclic aromatic hydrocarbons metabolites (1-hydroxynaphthalene, 2-hydroxynaphthalene, 2-hydroxyfluorene, 3-hydroxyfluorene, 1-hydroxyphenanthrene, 2-hydroxyphenanthrene, and 3-hydroxyphenanthrene and 1-hydroxypyrene) were examined to represent exposure of polycyclic aromatic hydrocarbons in the body. Weighted percentage and weighted mean were used to describe classified variable and continuous variable, respectively. We used weighted logistic regression to estimate the association of polycyclic aromatic hydrocarbons and osteoporosis. RESULTS: Five hundred seventy-seven (18.9%) osteoporosis patients were included. Among the eight polycyclic aromatic hydrocarbons metabolites, 3-hydroxyfluorene was associated with decreased odds of osteoporosis after controlling socio-demographic status, body mass index, alcohol, previous fracture, parental fracture, glucocorticoid use, dietary calcium intake, smoking, and other polycyclic aromatic hydrocarbons metabolites (OR = 0.63, 95%CI 0.41-0.98). 2-hydroxyfluorene (OR = 1.87, 95%CI 1.07-3.29) was associated with increased odds of osteoporosis. In the nonsmoking group, we found the association of osteoporosis with 2-hydroxyfluorene (OR = 2.56, 95%CI 1.10-5.96) and 3-hydroxyfluorene (OR = 0.41, 95%CI 0.22-0.77) still exists. CONCLUSION: Our study found that 3-hydroxyfluorene was associated with decreased odd of osteoporosis, while 2-hydroxyfluorene was associated with increased odds of osteoporosis. Our study was a cross-sectional study, therefore cohort studies or experimental studies about association of PAH and osteoporosis is needed.

Simultaneous determination of iprodione, procymidone, and chlorflurenol in lake water and wastewater matrices by GC-MS after multivariate optimization of binary dispersive liquid-liquid microextraction.

This study reports the optimization of a binary dispersive liquid-liquid microextraction method for the determination of iprodione, procymidone, and chlorflurenol by gas chromatography mass spectrometry. The study was aimed at using two extraction solvents to increase the extraction efficiency of all analytes. The binary solvents recorded results higher than the mono-solvents. After examining the effects of main experimental parameters and their interactions by analysis of variance, 200 µL of binary mixture (dichloromethane and 1,2-dichloroethane), 2.5 mL of ethanol, and 15 s vortex were obtained as optimum parameters. The detection and quantification limits calculated for the analytes were found to be between 0.30-1.6 and 1.0-5.3 ng/mL, respectively. Enhancement in detection power calculated as a ratio of the binary extraction detection limit to the detection limit of direct GC-MS analysis was 105-, 214-, and 233-fold for chlorflurenol, iprodione, and procymidone, respectively. In order to check the accuracy of the developed method, recovery study was performed. Water sampled from a lake and two wastewater samples from treatment facilities were spiked at two concentrations, and the percent recovery calculated for the samples ranged between 87 and 116%. These results confirmed the suitability of the method to real samples for accurate determination of the analytes at trace levels.

Fluorene oxidation by solar-driven photo-Fenton process: toward mild pH conditions.

Polycyclic aromatic hydrocarbons (PAHs) are on the list of priority pollutants to be eliminated from the environment due to their carcinogenic and mutagenic action, chemical stability, and resistance to biodegradation. The aim of this study was to evaluate the degradation of fluorene, a well-known PAH, in aqueous solutions (0.03 and 0.08 mg L-1), by means of a solar-driven conventional (PF) and modified photo-Fenton mediated by ferrioxalate complexes (PFF). Photolysis was also employed for comparison purposes. PF reaction was evaluated at different pH values (2.8, 3.5, and 4.0) and iron concentrations (2, 5, 10, and 20 mg L-1). On the other hand, PFF studies were conducted at mild pH conditions (4.0, 5.0, and 6.0) and iron content of 2 mg L-1, keeping initial iron/oxalate molar ratio at 1:3. In both PF and PFF, the initial hydrogen peroxide/iron molar ratio was maintained at 5. In the presence of methanol as cosolvent for fluorene dissolution, the PF reaction was hampered and no consumption of H2O2 was observed during the reaction carried out at constant pH (2.8). This led to low degradation rates, similar to those achieved by photolysis. Under the same pH but using acetonitrile as cosolvent for fluorene dissolution, fluorene degradation was found to be proportional to the iron content used in the PF experiments. On the other hand, at an invariable iron concentration of 5 mg Fe2+ L-1, the increase in pH was accompanied by a decrease in the molar fraction of the most photoactive iron complex (FeOH2+) and ferric hydroxides precipitation, leading to a reduction in the fluorene degradation rate. With regard to the PFF tests, similar fluorene degradation performance was achieved at pH 4 and 5, while at pH 6 iron precipitation became relevant and the degradation rate was slightly slower. PFF has shown to be more efficient than the PF under the same pH (4) and iron concentration (2 mg L-1). Moreover, even at near neutral pH (6), fluorine degradation was shown to be feasible by using ferrioxalate complexes.

Distribution, inhalation and health risk of PM2.5 related PAHs in indoor environments.

To investigate the potential cancer risk resulting from exposure to air pollutants, polycyclic aromatic hydrocarbons (PAHs) bound to airborne particles (PM2.5) were assessed in one outdoor environment and four indoor environments before and during the Spring Festival of 2015. The average total PAH concentration was site-dependent, and the concentration decreased before and during the Spring Festival. Fluoranthene (Flt) was the most commonly occurring among the 16 priority PAHs, and benzo(a)pyrene (BaP) accounted for the largest portion of the total carcinogenic potency of PAHs in PM2.5. The average BaP levels, in both indoor and outdoor environments, considerably exceeded the maximum permissible risk level of 1 ng/m3. Hazard quotients were found to be much less than 1, indicating little risk in terms of non-carcinogenic effects. Carcinogenic health risks resulting from possible carcinogens were determined to be much less than 1.00E-06. According to the California and WHO reference protocol, using empty room data to estimate the carcinogenic health risk produced values that were 10% lower than those calculated using outdoor environmental data.

Status, sources, and risk assessment of polycyclic aromatic hydrocarbons in urban soils of Xi'an, China.

To identify status, source of polycyclic aromatic hydrocarbons (PAHs) in urban soils and to assess soil environmental quality in Xi'an City, China, total 45 soil samples were collected from surface layer (0-10 cm) in different functional areas. Total concentrations of 16 US EPA priority PAHs ranged from 149.9 to 5770 µg kg-1, with a mean of 1246 µg kg-1. High molecular weight (HMW) PAHs accounted for the majority (42.4-72.2%) of the total PAHs in the urban soils, and phenanthrene (Phe), fluorene (Flo), pyrene (Pyr), benzo(b)fluoranthene (BbF), and chrysene (Chr) were the major compounds. Concentrations of PAHs varied among different functional areas. High level of PAHs was particularly apparent in industrial zones and city road overpass, while low level was recorded in scenic spots and campus. The integration of isomer ratios, principal component analysis (PCA), and positive matrix factor (PMF) indicated that the sources of PAHs in Xi'an urban soils were mainly derived from vehicle emissions and coal combustion. Based on incremental lifetime cancer risks (ILCR) model, the urban soils from the three functional areas (industrial zone, urban road, and city road overpass) posed potential cancer risk, and the cancer risks of direct ingestion for children were apparently higher than that for adolescence and for adult, respectively. Therefore, attention should be paid to the health risk for children exposed to PAHs in the urban soils.

Polycyclic aromatic hydrocarbons in teas using QuEChERS and HPLC-FLD.

Polycyclic aromatic hydrocarbons (PAHs) are food-processing contaminants considered to be carcinogenic and genotoxic. Due to its drying process stage, teas may be contaminated with PAHs. The aim of the study was to validate an analytical method involving QuEChERS and HPLC-FLD for the determination of PAH4 in teas and evaluate the contamination levels in 10 different types of teas from Brazil. Recoveries varied from 54% to 99% and relative standard deviations from 1% to 21%. Limits of detection and quantification were from 0.03 to 0.3 µg/kg and 0.1 to 0.5 µg/kg, respectively. Mate tea presented the highest PAH levels, with PAH4 varying from 194 to 1795 µg/kg; followed by black (1.8-186 µg/kg), white (24-119 µg/kg), and green teas (3.1-92 µg/kg). Teas with lowest PAH4 were strawberry, lemongrass, peppermint, and boldo. Only trace levels of PAHs were detected in tea infusions, so apparently it would not affect PAH intake by Brazilian population.