Polycyclic Aromatic Hydrocarbons Exposure Risk Research Articles

Concentrations, Source Apportionment and Health Risk Assessment of Polycyclic Aromatic Hydrocarbons (PAHs) in Household Dust Samples, the Case of City of Khorramabad, Iran

Individuals spend a lot of time indoors; thus, they can generally be exposed to polycyclic aromatic hydrocarbons (PAHs) such as teratogens, mutagens, and carcinogens with the potential of environmental and also human health risks. Therefore, the current study was conducted for the analysis, source identification, and health risk assessment of PAHs in household dust samples of the city of Khorramabad, Lorestan province, Iran in 2020. In so doing, 50 household dust samples were collected from 10 sampling sites. After extraction of the analytes, the gas chromatography/mass spectrometry (GC–MS) method was used to determine the PAHs contents in the samples. Sixteen priority PAHs were detected and quantified in the samples. The median values of ∑16PAHs were found to be 18.4 µg kg−1. Although based on the results of molecular diagnostic ratios (MDRs), PAH compounds could be originated from both petrogenic and pyrogenic sources, the pyrogenic sources including smoking, natural gas combustion, and traffic prevailed. Total incremental lifetime cancer risks (ILCRs) of children and adults with average values of 2.07E-04 and 1.83E-04, were both classified in the 'high critical value’ category. The cancer risk levels via dermal contact (1.15E-04) and direct ingestion (9.19E-05), indicated that both routes greatly contributed to the cancer risk for children. Similarly, the risk value of dermal contact (1.17E-04) and direct ingestion (6.58E-05) were found to be important pathways that adults could be exposed to contaminated dust. Accordingly, the mean values of ILCRs ranked in the following order: dermal contact > direct ingestion > inhalation for both cases (ie, children and adults). In conclusion, to maintain the health of both the man and the environment, it is recommended that regular and periodic analyses of these pollutants in different environmental samples including soil, sediment, dust, particulate matter, air, water, and tissues of living organisms in be performed to help prevent exposure risks of PAHs.

Spatiotemporal Distribution and Source Apportionment of Suspended Polycyclic Aromatic Hydrocarbons in Surface Water

Polycyclic aromatic hydrocarbons (PAHs) are a type of typical environmental pollutant with carcinogenic effects and high ecological risk. With the development of industry, surface water acts as a primary sink for PAHs. Owing to their low solubility, a significant amount of PAHs are adsorbed onto suspended particulate matter in surface water, which presents a serious risk to human health and the ecological environment. To protect human health and aquatic organisms, a systematic assessment of the trends in PAHs exposure risk is essential. Based on long-term monitoring data from 2002 to 2016, this study systematically evaluated the spatiotemporal distribution and source apportionment of PAHs adsorbed on suspended particulate matter in surface water. The results of the Mann-Kendall test indicated that pollution levels of PAHs decreased from 2012 to 2016. The maximum average content was 6239 μg·kg-1, and the minimum was 2760 μg·kg-1. Benzo(b)fluoranthene, benzo(k)fluoranthene, chrysene, and benzo(a)anthracene showed significant declines from 2002-2016 (P<0.05). Levels of benzo(a)pyrene, dibenzo(a,h)anthracene, and indeno(1,2,3-cd)pyrene were steady. Wavelet analysis showed that the pollution level of PAHs had significant periodic oscillations for surface water. Midstream and downstream Σ16PAHs showed significant declines from 2002-2016 (P<0.05), whereas upstream Σ16PAHs were steady. ANOVA analysis showed that the spatial difference was significant and occurred in the following order:midstream (6168 μg·kg-1)>upstream (5407 μg·kg-1)>downstream (3412 μg·kg-1). Diagnostic ratio analysis and the positive matrix factorization model suggested that the major sources of PAHs were traffic sources, coal burning sources, and biomass combustion sources, which accounted for 40.9%, 33.7%, and 25.4%, respectively. The contribution of traffic sources decreased by 25.9%. The contributions of coal burning sources and biomass combustion sources increased by 4.8% and 21.1% from 2002-2009 to 2010-2016, respectively. These results provide scientific reference for risk analysis and the control of PAHs pollution in surface water.

Insights into biomonitoring of human exposure to polycyclic aromatic hydrocarbons with hair analysis: A case study in e-waste recycling area

In this study, 96 pairs of hair and urine samples were collected from e-waste (EW) dismantling workers of an industrial park, as well as residents living in surrounding areas. The concentrations of polycyclic aromatic hydrocarbons (PAHs) and hydroxylated PAH metabolites (OH-PAHs) were analyzed . The results show that concentrations of Σ15PAHs ranged from 6.24 to 692 ng/g dry weight (dw) and Σ12OH-PAHs from undetected to 187 ng/g dw in hair external (hair-Ex), and ranged from 31.7 to 738 ng/g dw and 21.6 to 1887 ng/g dw in hair internal (hair-In). There was no significant difference in exposure levels between EW dismantling workers and residents of the surrounding area. For the parent PAHs, the concentrations of Σ15PAHs of hair-In were comparable with those of hair-Ex for all populations except for the child residents. On the contrary, for the OH-PAHs, the concentrations of Σ12OH-PAHs of hair-In were 9–37 times higher than those of hair-Ex for populations. Moreover, the congener profiles of OH-PAHs of hair-In were different from those of hair-Ex, but similar to that of urine. Particularly, 3-OH-Bap, which is a carcinogenic metabolite, was only detected in the hair-In. These results indicate that OH-PAHs in hair-In, just like in urine, are mainly derived from endogenous metabolism and could be considered as reliable biomarkers for PAHs exposure. However, there was almost no significant correlations between hair-In and urine for OH-PAHs. This indicates that more attention should be paid to OH-PAHs when conducting PAHs exposure risk assessment using hair, which will help to obtain more reliable and comprehensive information on health risk assessments.

A sixteen-year reduction in the concentrations of aquatic PAHs corresponding to source shifts in the Elbe River, Germany

Polycyclic aromatic hydro-carbons (PAHs) are carcinogenic, mutagenic, and teratogenic persistent organic molecules. To protect human health and aquatic organisms, a systematic assessment of the trends in PAH exposure risk and the key emission sources governing such trends is essential. Therefore, the long-term trends in PAH concentrations were assessed for the Elbe River, Germany, which represents a dynamic environment in which anthropogenic activities and nature exhibit complicated interactions. A Mann-Kendall trend test identified a general decreasing trend (a 38% reduction) in PAH concentrations over the last 16 years (2001–2016), which was consistent with a decline in the relative contribution from coke oven use (a 26–14% reduction). According to the source apportionment, an increasing number of source contributors were identified over time. Furthermore, PAH exposure risks for aquatic organisms and human health were calculated as risk quotient (RQ) and chronic daily intake (CDI). For most PAHs, the risk quotient of negligible concentrations (RQNCs) exceeded 1 and the risk quotient of maximum permissible concentrations (RQMPCs) was less than 1, indicating a middle-level ecological risk. In addition, the CDI-based hazard quotients suggested that the risk of human exposure to PAHs remained within acceptable limits during the study period. However, vehicular-associated benzo(a)pyrene (BaP) emissions contributed the most to human health risk. The data presented here suggest that substituting petroleum and coal with green energies will reduce PAH concentrations in aquatic environments.

Heavy Exposure of Waste Collectors to Polycyclic Aromatic Hydrocarbons in a Poor Rural Area of Middle China.

Manual collection and open-air incineration of waste materials is a common practice in rural regions of China and beyond. Low-temperature combustion of rubber and plastic waste generates high levels of airborne polycyclic aromatic hydrocarbons (PAHs). We investigated ten urinary hydroxylated PAH metabolites (OH-PAHs), the oxidative damage biomarker (8-hydroxy-deoxyguanosine, 8-OHdG), and four serum biomarkers including gamma-glutamyl transferase (GGT) and alanine aminotransferase (ALT) in 41 waste collectors and 122 control subjects residing in the same or a distant rural village in Henan Province. The level of PAH metabolites in urine (median: 17.24 μg/g Cre) was twice that of controls living in the same area without an occupational history involving waste collection (median: 8.16 μg/g Cre) and thrice that of controls living 30 km away (median: 6.07 μg/g Cre). The concentrations of OH-PAHs were positively associated with urinary 8-OHdG levels (β = 0.283, p < 0.05). Serum GGT and ALT were slightly increased in waste collectors. Urinary 8-OHdG levels were similar in one-year and longer-term workers, suggesting that rubber and plastic waste collection/incineration carries a high PAH exposure risk. These data provide solid baseline information, emphasizing the importance of monitoring the long-term health outcomes of waste collectors and changes in exposure patterns associated with rural development and regulation of waste disposal.

Statistical Modeling of Occupational Exposure to Polycyclic Aromatic Hydrocarbons Using OSHA Data

Polycyclic aromatic hydrocarbons (PAHs) are a group of pollutants with multiple variants classified as carcinogenic. The Occupational Safety and Health Administration (OSHA) provided access to two PAH exposure databanks of United States workplace compliance testing data collected between 1979 and 2010. Mixed-effects logistic models were used to predict the exceedance fraction (EF), i.e., the probability of exceeding OSHA's Permissible Exposure Limit (PEL = 0.2 mg/m3) for PAHs based on industry and occupation. Measurements of coal tar pitch volatiles were used as a surrogate for PAHs. Time, databank, occupation, and industry were included as fixed-effects while an identifier for the compliance inspection number was included as a random effect. Analyses involved 2,509 full-shift personal measurements. Results showed that the majority of industries had an estimated EF < 0.5, although several industries, including Standardized Industry Classification codes 1623 (Water, Sewer, Pipeline, and Communication and Powerline Construction), 1711 (Plumbing, Heating, and Air-Conditioning), 2824 (Manmade Organic Fibres), 3496 (Misc. Fabricated Wire products), and 5812 (Eating Places), and Major group's 13 (Oil and Gas Extraction) and 30 (Rubber and Miscellaneous Plastic Products), were estimated to have more than an 80% likelihood of exceeding the PEL. There was an inverse temporal trend of exceeding the PEL, with lower risk in most recent years, albeit not statistically significant. Similar results were shown when incorporating occupation, but varied depending on the occupation as the majority of industries predicted at the administrative level, e.g., managers, had an estimated EF < 0.5 while at the minimally skilled/laborer level there was a substantial increase in the estimated EF. These statistical models allow the prediction of PAH exposure risk through individual occupational histories and will be used to create a job-exposure matrix for use in a population-based case-control study exploring PAH exposure and breast cancer risk.

Distribution and Source Apportionment of Polycyclic Aromatic Hydrocarbons in Bank Soils and River Sediments From the Middle Reaches of the Huaihe River, China

Bank surface soil and river sediment samples from the middle reaches of the Huaihe River were analyzed by GC‐MS for polycyclic aromatic hydrocarbons (PAHs). The total PAHs concentrations ranged from104 to 947 ng/g in bank soils and from 83 to 2599 ng/g in river sediments. The PAHs levels of the studied samples are relatively higher as compared to those from other world regions, which suggest an enhanced deposition of atmospheric PAHs derived from the emissions of fossil fuel combustion in this area. Possible sources from soil and sediments were diagnosed by the paired PAHs isomer ratios and principal components analysis, and the results indicate that the PAHs in the soils mainly came from coal combustion (74%) followed by combustion of refined petroleum products (26%), and in the sediments mainly from pyrogenic sources (89%) followed by petroleum sources of oil spill emissions (11%). The PAHs exposure risk assessments show that PAHs in majority of the sediments did not pose threats to the ambient ecosystem. However, the calculated total toxic benzo[a]pyrene (BaP) equivalent of PAHs in soil and sediment indicate that BaP is the most potentially carcinogenic individual PAH.

Spatial distribution, potential risk assessment, and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in sediments of Lake Chaohu, China.

Twenty-nine sediment samples were collected from Lake Chaohu, a shallow eutrophic lake in Eastern China, and were analyzed for 15 priority polycyclic aromatic hydrocarbons (PAHs) to determine the spatial distribution and exposure risks of PAHs. Three receptor models, the principal component analysis-multiple linear regression (PCA-MLR) model, the positive matrix factorization (PMF) model, and the Unmix model, were used in combination with the PAHs diagnostic ratios to investigate the potential source apportionment of PAHs. A clear gradient in the spatial distribution and the potential toxicity of PAHs was observed from west to east in the sediments of Lake Chaohu. ∑15PAH concentrations and the TEQ were in the range of 80.82-30 365.01 ng g(-1) d.w. and 40.77-614.03, respectively. The highest values of the aforementioned variables were attributed to urban-industrial pollution sources in the west lake region, and the levels decreased away from the river inlets. The three different models yielded excellent correlation coefficients between the predicted and measured levels of the 15 PAH compounds. Similarly, source apportionment results were derived from the three receptor models and the PAH diagnostic ratios, suggesting that the highest contribution to the PAHs was from coal combustion and wood combustion, followed by vehicular emissions. The PMF model yielded the following contributions to the PAHs from gasoline combustion, diesel combustion, unburned petroleum emissions, and wood combustion: 34.49, 24.61, 16.11, 13.01, and 11.78 %, respectively. The PMF model produced more detailed source apportionment results for the PAHs than the PCA-MLR and Unmix models.

Particulate polycyclic aromatic hydrocarbons in the urban Northeast Region of China: Profiles, distributions and sources

In this study, concentrations of polycyclic aromatic hydrocarbons (PAHs) associated with PM10 were measured to examine the status, characteristics and sources of atmospheric PAH pollution in the industrial Northeast Region of China. Mean concentrations of total PAHs were 65.5, 40.0, 73.0 and 436.7 ng m−3 in the four seasons respectively. The calculated BaPeq concentrations in winter all exceeded the national standard, imposing serious PAH exposure risk. PAH concentrations varied between the cities, but PAH concentrations in different functional areas within a city did not show significant difference. In general, particulate PAH profiles were dominated by 4- and 5-ring compounds. Elevated proportions of 3-ring PAHs and 5-ring PAHs were found in winter and in summer respectively. Diagnostic ratios and principal component analysis (PCA) were used to identify potential sources of PAHs. Coal combustion activities were the main contributors of particle-associated PAHs in this region.