Polycyclic Aromatic Hydrocarbons in Soil and Human Health Risk Levels for Various Land-Use Areas in Ulsan, South Korea

Multiplicity and complexity in sources account for polycyclic aromatic hydrocarbons (PAHs) in soil and health risk levels in industrial zones. In the present study, cancer risks (CR) for soil-bound carcinogenic PAHs were estimated and compared for the first time in seven different land-use areas adjacent to an industrial zone (Ulsan) in Korea. The entire study area has been recognized as a “low CR” zone (10−6 < value < 10−4). Hence, all land-use areas were found to have significant (>10−6) CR levels, except for an area used to store ore and iron scraps. Estimated CR levels were highest in the railroad area (RA) and traffic area (TA), followed by those in the industrial area (IA). In addition, exposure through dermal absorption (61–70%) and ingestion (21–39%) were the most common factors for CR levels in the study area. Among all health parameters, exposure duration, body weight, and open skin surface area were distinguished as most sensitive to total CR levels. Moreover, among all carcinogenic PAHs, indeno[1,2,3-c,d]pyrene and benzo[a]pyrene were most sensitive to CR levels. Creosote, which was utilized in railroad ties in RA and vehicular exhaust emission in TA, was classified as a source of soil-bound carcinogenic PAHs. Therefore, CR levels resulting from transportation activities were found to be two to three times higher than those obtained from industrial processes. Transportation activities in urban areas mostly serve to provide rapid and comfortable carriage for commuters. However, these facilities were mostly responsible for potential carcinogen exposure. This study directly challenges the conventional perception that industrial zones are the most polluted areas, especially when compared to transportation zones in urban areas. These findings can help local and national governments to better manage resources and maintain an economic balance.

Carcinogenic Content of PM10-Bound PAHs in University Classrooms and Outdoors at an Urban Location in Rome, Italy, during Winter Working and Not-Working Days

To assess the contribution of carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) in ambient air, EU Directive 2004/107/EC indicates to monitor relevant carcinogenic PAHs in PM10 fraction other than benzo(a)pyrene at a limited number of measurement sites. This indication refers to outdoor environments, and the environmental air quality being taken as a reference also for indoors, it can be extended to indoor environments. In this work, the contribution of carcinogenic PAHs bound to PM10 has been evaluated in winter in two classrooms of a University campus in Rome with the aim of studying the relationship with the outdoors and with working activity. PM10-boundPAHs were monitored over five different periods selected to distinguish Weekend from daytime and nighttime Weekdays, separated into two parts of the week. Data aggregated over Weekend and Weekdays allowed calculating of the concentration of carcinogenic PAHs, the mass contribution to PM10, the Infiltration Factor, the indoor to outdoor Ratio, and the Total Carcinogenic Potency by Toxicity Equivalent Factors, for “not-working” and “working” days. In addition, some indications on contributions to the source have been obtained from the chemical profile normalized to the maximum value of concentration, which also provides the source fingerprint compound. Indoor PAH concentrations were lower than outdoor, and both accumulated as the week progressed. Although the two indoor environments were on the same floor and had a similar volume, they presented different contribution to PM10 and infiltration capacity, both higher during Weekend than on Weekdays. The analysis of indoor and outdoor chemical profiles normalized to the maximum concentration indicated an external source infiltrating the indoors environment. During Weekdays, the indoor fingerprint compound changed compared to that observed during Weekend, probably due to an additional contribution of local “fresh-traffic” source. The calculation of Total Carcinogenic Potency gave indoor values always lower than outdoor, confirming in the two classrooms different dynamics for carcinogenic PAHs. Moreover, the Total Carcinogenic Potency on Weekdays was twice that of Weekend, meaning a higher toxicological impact when urban “fresh-traffic” source is added. The present study shows that the dynamics of PM10-related carcinogenic PAHs can be different within adjacent classrooms of a building and during working and not-working days. This evidence suggests the possibility of a potential different impact on occupant exposure to be taken into account in planning monitoring programs of indoor pollution.

Multiple categories of polycyclic aromatic hydrocarbons in atmospheric PM2.5 associated with changes in lipid profiles: a longitudinal study in Beijing

Background Lipid disorder has been demonstrated as important biomarkers for many chronic diseases, while PM2.5 is becoming an emerging risk factor to altered lipid profiles. However, few studies have paid attention to the changes of comprehensive lipid indices caused by PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) exposure, especially among older adults population. We aimed to investigate whether PM2.5-bound PAHs were associated with the changes of lipid profiles, and whether this association could differ among multiple categories of PAHs. Methods A longitudinal study including 98 adults was conducted in Beijing, China, from November 2016 to January 2018. Multiple categories of PAHs were classified into low-molecular-weight PAHs (LMW-PAHs), high-molecular-weight PAHs (HMW-PAHs), carcinogenic PAHs (c-PAHs) and non-carcinogenic PAHs (nc-PAHs) based on their molecular weight and carcinogenicity potential. Linear mixed-effects models were used to explore the association between multiple categories of PAHs and lipid profiles, including single-pollutant model, two-pollutant model, and constituent-residual model. Results We found that high-density lipoprotein cholesterol (HDL-C) levels were significantly decreased by 1.00% (95%CI, -1.98 to -0.30%) to 9.52% (95%CI, -13.93 to -4.88%) in association with a 10 ng/m3 increase in moving averages of the multiple categories of PAHs. We also found significant increases in total cholesterol (TG), castelli risk indexes I and II (CRI-I and II), and atherogenic coefficient (AC) by 4.08% (95% CI, 0.10 to 7.25%) to 40.49% (95% CI, 13.88 to 73.33%) were associated with a 10 ng/m3 increase of multiple categories of PAHs. Conclusion Multiple categories of PAHs were significantly associated with altered lipid profiles. Although some PAHs are not carcinogenic, they may cause dyslipidemia, which in turn affects chronic diseases.

Environment impact and probabilistic health risks of PAHs in dusts surrounding an iron and steel enterprise

Dust can be regarded as environmental medium that indicates the level and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) coming from different pollution sources. In this study, samples including road dust, roof dust, and bare soil near an iron and steel enterprise (ISE) in Laiwu city of North China were collected. To assess the environment impact, atmosphere particulates and one flue dust from a coking plant were simultaneously sampled. Sixteen USEPA PAHs were detected quantitatively by Gas Chromatography Mass Spectrometry (GC–MS). A laser particle size analyzer was used to obtain the grain size of the dust particle samples. The results showed that PAH concentrations displayed great variability in the dust samples. The ∑16PAHs concentration was found to be between 0.460 and 46.970 μg/g (avg ± sd 10.892 ± 1.185 μg/g) in road dust, between 0.670 and 17.140 μg/g (avg ± sd 6.751 ± 0.692 μg/g) in roof dust, and 13.990 ± 1.203 μg/g in bare soil. In the environment atmosphere sites, the ∑16 PAHs value in PM2.5 constituted a very large proportion of PM10, indicating that PAHs in finer particle sizes should be given greater emphasis. The ∑16PAHs concentration was relatively high in the area close to the ISE because of the great impact of the ISE industrial activities. PAH concentration curves were similar, and the most abundant individual PAHs in the atmosphere sites were BbF, BkF, and Flu, and BbF, BkF, and Chry in dusts. Toxicity analysis revealed that PAHs with four rings, including carcinogenic PAHs, were the dominant pollutants in the studied area. The toxic equivalency value (TEQBaP), the carcinogenic health risk assessment value recommended by the US EPA, was calculated for seven carcinogenic PAHs, revealing that they account for more than 93.0% of the total TEQBap of the 16 PAHs and indicating the major toxic equivalent concentration contributor. Incremental lifetime cancer risk (ILCR) estimation results showed that PAHs tended to bring about great health risks through skin contact, followed by ingestion and inhalation. By comparison, road dust exhibited greater carcinogenic risks than roof dust, and bare soil may undergo heavier pollution. Therefore, the results of this study would be helpful in the effort to understand the PAHs pollution from the steel industry, which will provide some guidance for the probabilistic assessment of local health risks.

Could pollution levels, characteristics, sources of PAHs in atmospheric particulate matter break the Hu line?

Were the pollution levels, characteristics and sources of PAHs related to the population and GDP on both sides of the Hu line? What was the relationship between them? The study summarizes and discusses available data for PAHs in atmospheric particulate matter (PM) from 93 above prefecture-level cities in China in 2000-2019. The results suggested that the concentration of PAHs in PM varied with 7 regions of China in descending order: Northeast (NE) > North China (NC) > Northwest (NW) > South China (SC) > Southwest (SE) > Central China (CC) > South China Sea (SCS). Meanwhile, the mean value of carcinogenic PAHs, non-carcinogenic PAHs, PAHs derived from the burning of organic matter, low molecular weight PAHs, medium molecular weight PAHs, and high molecular weight PAHs in 16 priority PAHs was 53.5%, 46.5%, 80.0%, 16.9%, 45.2%, 37.9%, respectively. Moreover, from NW to NC, the content and pollution of PAHs increased with the increase of population and gross domestic product (GDP). From CC to SW and NC, the content and pollution of PAHs increased with the increase of population and the decrease of GDP. From SW to NW and CC to SC, the content and pollution of PAHs increased with the decrease in population and GDP. In part, PAHs pollution, characteristics and sources of atmospheric PM in Chinese cities broke the Hu line of population and GDP. Therefore, these require the promotion of comprehensive measures that will reduce pollution and sources of PAHs in heavily polluted areas.

Environment Impact and Probabilistic Health Risks of PAHs In Dusts Surrounding an Iron and Steel Enterprise

Dust can be regarded as environmental medium that indicates the level and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) coming from different pollution sources. In this study, samples including road dust, roof dust, and bare soil near an iron and steel enterprise (ISE) in Laiwu city of North China were collected. To assess the environment impact, atmosphere particulates and one flue dust from a coking plant were simultaneously sampled. Sixteen USEPA PAHs were detected quantitatively by Gas Chromatography Mass Spectrometry(GC-MS). A laser particle size analyzer was used to obtain the grain size of the dust particle samples. The results showed that PAH concentrations displayed great variability in the dust samples. The ∑16 PAHs concentration was found to be between 0.460 and 46.970 μg/g (avg ± sd: 10.892 ± 1.185 μg/g) in road dust, between 0.670 and 17.140 μg/g (avg ± sd: 6.751 ± 0.692 μg/g) in roof dust, and 13.990 ± 1.203 μg/g in bare soil. In the environment atmosphere sites, the ∑16 PAHs value in PM2.5 constituted a very large proportion of PM10, indicating that PAHs in finer particle sizes should be given greater emphasis. The ∑16PAHs concentration was relatively high in the area close to the ISE because of the great impact of the ISE industrial activities. PAH concentration curves were similar, and the most abundant individual PAHs in the atmosphere sites were BbF, BkF, and Flu, and BbF, BkF, and Chry in dusts. Toxicity analysis revealed that PAHs with four rings, including carcinogenic PAHs, were the dominant pollutants in the studied area. The toxic equivalency value (TEQBaP), the carcinogenic health risk assessment value recommended by the US EPA, was calculated for seven carcinogenic PAHs, revealing that they account for more than 93.0% of the total TEQBap of the 16 PAHs and indicating the major toxic equivalent concentration contributor. Incremental lifetime cancer risk (ILCR) estimation results showed that PAHs tended to bring about great health risks through skin contact, followed by ingestion and inhalation. By comparison, road dust exhibited greater carcinogenic risks than roof dust, and bare soil may undergo heavier pollution. Therefore, the results of this study would be helpful in the effort to understand the PAHs pollution from the steel industry, which will provide some guidance for the probabilistic assessment of local health risks.

Effect of Excess Air Levels on PAHs Content in Smoke During Charcoal Combustion in Grilling Process

Charcoal grilling may lead to carcinogenic PAHs contamination of grilled food from incomplete combustion of charcoal. The objective of this study was to determine the effect of complete combustion of charcoal on PAHs content in smoke during the grilling process. Firstly, proximate and ultimate compositions of the charcoal were determined to identify the amount of air required for combustion according to stoichiometry. Different excess air levels consisting of stoichiometric air, 60, 100 and 150% excess air during combustion of charcoal on 16 PAHs released in smoke were studied. Moreover, CO and CO2 concentrations were measured. The use of excess air decreased the emission factor of CO and increased the emission factor of CO2. The 16 PAHs contents in smoke produced from charcoal combusted with stoichiometric air, 60, 100 and 150% excess air were 73.62, 51.78, 27.68 and 19.23 μg/kg dry charcoal, respectively. The use of excess air during charcoal combustion resulted in significantly lower PAHs contents in the smoke. Therefore, the use of excess air during charcoal grilling is one way to reduce the risk of PAHs contamination in grilled food.