Levels Of Particulate Polycyclic Aromatic Hydrocarbons Research Articles

Long-term (1993–2018) particulate polycyclic aromatic hydrocarbons (PAHs) concentration trend in the atmosphere of Seoul: Changes in major sources and health effects

This study assessed the long-term concentration trend and profiles of twelve polycyclic aromatic hydrocarbons (PAHs) occurring as airborne particulate matter in Seoul, Republic of Korea (Korea) between 1993 and 2018 to evaluate the human health effect and the effectiveness of air quality management policies. Total PAHs (∑PAHs of 12 compounds), benzo [a]pyrene (BaP), and BaP toxic equivalent (BaPTEQ) concentrations increased from 1993 to 1999 but decreased thereafter. Moreover, the BaP concentration has remained below 1 ng/m3 since 2010–2011. Benzo [b+k]fluoranthene (B [b+k]F) accounted for the largest ∑PAHs fraction (approximately 24%) for the entire period. Based on the PAH profiles, as well as the Principal Component Analysis (PCA) results and diagnostic ratio analysis, vehicular emissions and coal combustion were identified as major sources of the PAHs in Seoul. Additionally, contribution of vehicular emissions increased from 2002 to 2003 to 2018, whereas that of solid fuel combustion decreased in the same period. PAH levels increased 8-fold in winter compared to summer mainly due to increases in local and regional emissions. The implementation of policies to regulate the use of solid fuels and vehicular emissions in Korea effectively reduced Elemental Carbon (EC) and PAH emissions, as demonstrated by CO, EC, and PAHs reductions and a good correlation between EC and PAHs. Moreover, aggressive air quality management policies in China have also contributed to decreasing PAH concentration trend in Seoul. Following the incremental lifetime cancer risk (ILCR) estimations method for 8 different population groups, males in the 0–1 age group was the only group still at potential risk of PAH inhalation in 2018, while other groups have been in the acceptable risk since 2012–2013.

Source apportionment and seasonal variation in particulate PAHs levels at a coastal site in Belgium.

In the present study, estimation of the atmospheric polycyclic aromatic hydrocarbons (PAHs) was done in particulate samples collected from De Haan, Belgium, during different seasons. The sampling site was situated very close to the north sea and far from the influence of local or industrial activities. The levels of PAHs depicted a distinct seasonal trend, being highest during the spring season. The observations of the study indicated a mean value of 2.6ngm-3 for concentration of all the 16 US EPA PAHs, thus being significantly lower when compared to results of previous studies focused on other sites. The dominating PAHs species reported were naphthalene, fluoranthene, benzo[a]anthracene, chrysene, and indeno[1,2,3c,d] pyrene. Assessment of the seasonal variation of the PAH levels was also done with respect to diagnostic ratio-based source identification, analysis of back trajectories, and principle component analysis. Burning of fossil fuels was observed to be the prominent source of atmospheric PAHs in the study area. Further, lifetime cancer risk assessment was performed to assess the detrimental health impacts on humans on being exposed to atmospheric PAHs. Particulate PAHs present in the ambient air of Belgium shows no carcinogenic health impacts. However, considering the industrial expansion in the region, efforts are required to prevent the environmental contamination of PAHs. Graphical abstract.

Distribution characteristics of and personal exposure with polycyclic aromatic hydrocarbons and particulate matter in indoor and outdoor air of rural households in Northern China

Gaseous and particulate polycyclic aromatic hydrocarbons (PAHs) and size-segregated particulate matter (PM) in indoor air and outdoor air, along with personal exposure, were monitored in rural households of Northern China. The daily average concentrations of 28 species were 1310 ± 811, 738 ± 321, 465 ± 247, and 655 ± 250 ng/m3 in kitchen air, bedroom air, and outdoor air, and for personal exposure, respectively. PAHs tended to occur in the particulate phase with increasing molecular weight. Absorption by particulate organic carbon was dominant in the gas-particle partitioning process. The daily averaged concentrations of PM2.5 and PM1.0 were 104 ± 39.5 and 88.4 ± 39.3 μg/m3 in kitchen air, 79.0 ± 63.2 and 65.7 ± 57.5 μg/m3 in bedroom air, 52.9 ± 16.5 and 41.5 ± 12.5 μg/m3 in outdoor air, and 71.7 ± 30.8 and 61.5 ± 28.4 μg/m3 for personal exposure, respectively. The non-priority components contributed 5.5 ± 2.8% to the total PAHs, while their fraction of carcinogenic risk reached 85.6 ± 6.9%. The mean cancer risk posed to rural residents via inhalation exposure to PAHs exceeded the current acceptable threshold of 1.0 × 10−6 and the national average estimated in China. The personal exposure levels of PAHs and PM in households using clean energy were lower than those in households using traditional biomass by 30.0%, 29.4%, and 38.5% for PAH28, PM2.5, and PM1.0, respectively. However, the cancer risk of personal inhalation exposure to PAH28 from using liquid petroleum gas (LPG) was higher than that from using firewood, implying the adoption of LPG may not effectively reduce the cancer risk despite the decreasing exposure levels of PAH28 and PM with respect to the use of firewood. Cooking individuals suffered higher exposure levels of PAH28 and PM1.0 compared with non-cooking individuals, and the cancer risk of personal inhalation exposure to PAH28 for cooking individuals was 1.7 times that for non-cooking individuals. Cooking was a critical factor that affected the personal exposure levels of the local male and female residents.

Seasonal characteristics of particulate polycyclic aromatic hydrocarbons (PAHs) in a petrochemical and oil refinery industrial area on the west coast of South Korea

The Daesan industrial complex is one of the largest petrochemical and oil refinery industrial complexes in South Korea, which is believed to be a major source of polycyclic aromatic hydrocarbons (PAHs). Total suspended particle (TSP) samples (n = 84) were seasonally collected at two industrial sites and one residential site, and 19 PAHs were analyzed. Concentrations of individual PAHs ranged from 0.01 to 2.52 ng/m3, and annual mean concentrations of Σ19 PAHs at Sites 1, 2, and 3 were 5.88, 4.52, and 5.08 ng/m3, respectively. The concentrations of Σ19 PAHs in warm seasons (spring and summer) were lower than those in cold seasons (autumn and winter). Annual fractions of low molecular weight (LMW)-PAHs (2–3 rings, 12.1%) and high molecular weight (HMW)-PAHs (4–7 rings, 87.9%) indicated a strong contribution of thermal processes. Significant correlations between Σ19 PAHs and TSP (p < 0.01) at all the sampling sites were observed, implying that increased TSP levels were responsible for elevated levels of PAHs. There were strong seasonal variations in the profiles of PAHs, and they were clearly reflected in the results of the principal component analysis. Diagnostic ratios and backward air trajectories suggested seasonal variations in the contribution of local emissions and long-range transport. The diagnostic ratios suggested that mixed sources were dominant in cold seasons, while coal/biomass burning and non-traffic sources were prevailing in warm seasons. BeP/BaP ratios indicated that local emissions were major sources compared with long-range transport except for summer. Backward air trajectories in winter suggested the influence of long-range transport, but local emissions were more important in this study area.

Sources and spatial distribution of particulate polycyclic aromatic hydrocarbons in Shanghai, China.

Atmospheric particulate polycyclic aromatic hydrocarbons (PAHs) have been drawing sustained attention due to their health risk and effects on air pollution. It is essential to determine the main sources and reduce atmospheric levels of PAHs to protect human health. PAHs in PM2.5 have been detected at five sites located in five districts in Shanghai, a modern metropolitan city in China. Spatial and temporal variations of composition profiles and sources of PAHs at each site in each season were investigated. The results showed that atmospheric particulate PAHs level in Shanghai was the lowest in summer and the highest in winter, dominated by high molecular weight (HMW) PAHs. Analysis with a combination of coefficients of Pearson's correlation and coefficient of divergences indicated heterogeneous spatial and temporal distribution for LMW PAHs and homogenous distribution for HMW PAHs. Diagnostic ratios and positive matrix factorization (PMF) model both identified pyrogenic sources as the main contributor of PAHs in Shanghai, with vehicular source contribution of 32-43% to the total PAHs annually and around 20% from biomass burning emissions in urban and urban buildup areas. While in winter, coal combustion and biomass burning could act as two major sources of PAHs in suburban areas, which could contribute to >70% of total PAHs measured in PM2.5 in Shanghai.

Factors affecting the level and pattern of polycyclic aromatic hydrocarbons (PAHs) at Gosan, Korea during a dust period

Polycyclic aromatic hydrocarbons (PAHs) in both gas and total suspended particles were measured at Gosan, Jeju Island in Korea, a remote background site, for 15 days (March 29–April 12, 2002). During the sampling period, a severe three-day Asian dust (AD) event originating from Mongolia and northern China was observed throughout the Korean Peninsula and Jeju Island. In addition, pollution (PO) and normal (NO) periods were also identified based on the levels of anthropogenic pollutants. Despite a large difference of PM10 concentrations between the AD and PO periods, the levels of particulate PAHs in both periods were comparable (2.7±1.0 and 2.4±0.5ngm−3, respectively) since they were determined by the concentration of anthropogenic PM2.5 transported from industrial areas of China. In the AD period, the level of gaseous PAHs, which were mostly from local sources, was the lowest due to strong winds; the gas/particle partitioning was close to equilibrium as the effect of long-range transport was manifested. The results of backward air trajectories, correlation analysis, and diagnostic ratios show that long-range transport of particulate PAHs produced by coal/biomass burning in China could strongly affect the levels and patterns of PAHs at Gosan, Korea.

Fine particle air pollution and secondhand smoke exposures and risks inside 66 US casinos

Smoking bans often exempt casinos, exposing occupants to fine particles (PM 2.5) from secondhand smoke. We quantified the relative contributions to PM 2.5 from both secondhand smoke and infiltrating outdoor sources in US casinos. We measured real-time PM 2.5, particulate polycyclic aromatic hydrocarbons (PPAH), and carbon dioxide (CO 2) (as an index of ventilation rate) inside and outside 8 casinos in Reno, Nevada. We combined these data with data from previous studies, yielding a total of 66 US casinos with smoking in California, Delaware, Nevada, New Jersey, and Pennsylvania, developing PM 2.5 frequency distributions, with 3 nonsmoking casinos for comparison. Geometric means for PM 2.5 were 53.8 μg/m 3 (range 18.5–205 μg/m 3) inside smoking casinos, 4.3 μg/m 3 (range 0.26–29.7 μg/m 3) outside those casinos, and 3.1 μg/m 3 (range 0.6–9 μg/m 3) inside 3 nonsmoking casinos. In a subset of 21 Reno and Las Vegas smoking casinos, PM 2.5 in gaming areas averaged 45.2 μg/m 3 (95% CI, 37.7–52.7 μg/m 3); adjacent nonsmoking casino restaurants averaged 27.2 μg/m 3 (95% CI, 17.5–36.9 μg/m 3), while PM 2.5 outside the casinos averaged 3.9 μg/m 3 (95% CI, 2.5–5.3 μg/m 3). For a subset of 10 Nevada and Pennsylvania smoking casinos, incremental (indoor–outdoor) PM 2.5 was correlated with incremental PPAH ( R 2=0.79), with ventilation rate-adjusted smoker density ( R 2=0.73), and with smoker density ( R 2=0.60), but not with ventilation rates ( R 2=0.15). PPAH levels in 8 smoking casinos in 3 states averaged 4 times outdoors. The nonsmoking casinos' PM 2.5 ( n=3) did not differ from outdoor levels, nor did their PPAH ( n=2). Incremental PM 2.5 from secondhand smoke in approximately half the smoking casinos exceeded a level known to produce cardiovascular morbidity in nonsmokers after less than 2 h of exposure, posing acute health risks to patrons and workers. Casino ventilation and air cleaning practices failed to control secondhand smoke PM 2.5. Drifting PM 2.5 from secondhand smoke contaminated unseparated nonsmoking areas. Smoke-free casinos reduced PM 2.5 to the same low levels found outdoors.

Personal exposure to particulate PAHs and anthraquinone and oxidative DNA damages in humans

Recent studies suggest that DNA oxidative damage be related to the chemical constituents of ambient particles. The purpose of this study was to examine whether particulate polycyclic aromatic hydrocarbons (PAHs) and quinone-structure chemicals increase body burden of oxidative stress in human exposed to heavy traffic volume. We recruited two nonsmoking security guards who worked at a university campus gate near a heavily trafficked road. Each subject wore a personal air sampler for 24 h per day to estimate exposures to 24 PAHs and anthraquinone (AnQ) in PM 2.5. Daily pre- and post-work shift spot urines were collected for 29 d from each subject. Urine samples were analyzed for 8-hydroxy-2′-deoxyguanosine (8-OHdG). Additionally, using 19 organic tracers other than 24 PAHs and AnQ, a receptor source apportionment model of chemical mass balance was applied to determine the contributions of sources on the PM: gasoline vehicle, diesel vehicle, coal burning, vegetable debris, cooking, natural gas and biomass burning. The relationship among urinary 8-OHdG, individual PAH, and AnQ was demonstrated as follows: the average urinary concentration of 8-OHdG was increased more than three times after 8-h work-shift than those before the work shift. All the 24 PAH and AnQ levels were positively and significantly associated with the post-work urinary 8-OHdG. The results from source apportionment suggest vehicular emission to be the dominant source of personal exposure to PM 2.5. Our finding indicates that personal air exposures to 24 individual PAHs and AnQ originating from traffic emissions are important in increasing oxidative burdens in human body.

The Impact of Ontario Smoke-Free Legislation on Secondhand Smoke in Enclosed Public Places

Many studies have evaluated the impact of indoor smoking bans on secondhand smoke (SHS) exposure. No studies have assessed the impact of a smoking ban on SHS in enclosed areas outside separately ventilated, designated smoking rooms (DSRs). This study evaluated the overall impact of the Smoke-Free Ontario Act implemented May 31, 2006, on SHS in bars and coffee shops and the impact of banning DSRs on SHS outside DSRs. Air particulate matter (PM) and carcinogenic particulate polycyclic aromatic hydrocarbons (PPAH) were measured in May 2006 before the ban inside and outside DSRs in Toronto venues (13 coffee shops and 14 bars) that allowed smoking only in DSRs, and in Windsor venues (10 coffee shops and 10 bars) where smoking was allowed in shared spaces. Measurements were repeated 2 months post-ban. Air quality index values (AQIs) were calculated. Mixed model analysis was applied, taking into account measurement errors for repeated measures. Post ban, mean PM and PPAH levels were reduced by 87% (from 494 to 67 mm2/m3) and 94% (from 196 to 11 ng/m3), respectively, inside Toronto DSRs. Mean PM and PPAH levels were reduced by 10% (from 124 to 111 mm2/m3) and 46% (from 45 to 24 ng/m3), respectively, outside Toronto DSRs. In all Windsor venues, mean PM and PPAH levels were reduced by 83% (from 488 to 81 mm2/m3) and 90% (from 107 to 10 ng/m3), respectively. All reductions were statistically significant (p < 0.0001). In Toronto venues, the AQI was reduced from the “very unhealthy” range inside DSRs and the “moderate” range outside Toronto DSRs to the “good” range, and in Windsor venues from the “unhealthy for sensitive groups” range to the “good” range post-ban. Pre-ban PPAH levels including those outside Toronto DSRs may be associated with cardiovascular injury. DSRs did not provide adequate protection from SHS. The Smoke-Free Ontario Act produced a significant and firm reduction in SHS exposure in venues both with and without DSRs.

Do indoor smoke-free laws provide bar workers with adequate protection from secondhand smoke?

Objective To determine if bar workers are adequately protected from secondhand smoke by an Act that prohibits indoor smoking in public workplaces, including bars and restaurants, but allows smoking on unenclosed contiguous patios. Methods A purposive sample of 25 bars with outdoor patios in Toronto, Canada was drawn. Air carcinogenic particulate polycyclic aromatic hydrocarbons (PPAH) were measured on patios and inside bars in August–September, 2006, 2–3 months after implementation of the Smoke-Free Ontario Act. Taking into account repeated measures, mixed model analysis was applied to examine the level of fine particle PPAH (ng/m 3) by number of lit cigarettes per patio area. Results Smoking on patios was common. With increasing numbers (0, 1.0–4.3, 4.4–8.7, 8.8–16.7 and 16.8–41.7) of lit cigarettes per 1000 ft 2 of patio area, there were increases in geometric mean (geometric standard deviation) PPAH levels, 4.7 (2.4), 9.1 (3.7), 16.9 (2.9), 19.1 (3.0) and 27.0 (2.9) ng/m 3 on patios. Mixed model analysis showed that PPAH levels increased significantly with number of lit cigarettes per patio area ( p = 0.0004). High levels of PPAH on patios may be associated with sustained vascular injury. Conclusions Complete smoking bans including outdoor workspaces are needed to adequately protect hospitality workers from secondhand smoke.

Depletion of gaseous polycyclic aromatic hydrocarbons by a forest canopy

Abstract. Rapid uptake of gaseous polycyclic aromatic hydrocarbons (PAHs) by a forest canopy was observed at Borden in Southern Ontario, Canada during bud break in early spring 2003. High volume air samples were taken on 12 individual days at three different heights (44.4, 29.1, and 16.7 m) on a scaffolding tower and on the forest floor below the canopy (1.5 m). Concentrations of PAHs were positively correlated to ambient temperature, resulting from relatively warm and polluted air masses passing over the Eastern United States and Toronto prior to arriving at the sampling site. An analysis of vertical profiles and gas/particle partitioning of the PAHs showed that gaseous PAHs established a concentration gradient with height, whereas levels of particulate PAHs were relatively uniform, implying that only the uptake of gaseous PAHs by the forest canopy was sufficiently rapid to be observed. Specifically, the gaseous concentrations of intermediate PAHs, such as phenanthrene, anthracene, and pyrene, during budburst and leaf emergence were reduced within and above the canopy. When a gradient was observed, the percentage of PAHs on particles increased at the elevations experiencing a decrease in gas phase concentrations. The uptake of intermediate PAHs by the canopy also led to significant differences in gaseous PAH composition with height. These results are the most direct evidence yet of the filter effect of forest canopies for gaseous PAHs in early spring. PAH deposition fluxes and dry gaseous deposition velocities to the forest canopy were estimated from the concentration gradients.

Variation in particulate PAHs levels and their relation with the transboundary movement of the air masses

The levels of particulate polycyclic aromatic hydrocarbons (PAHs) were determined with a fast analytical approach to study their seasonal variations at Menen (Belgium) during 2003; they were found to be 5–7 times higher in January, February and December, in comparison to May, June and August. The annual average concentration of the sum of 16 US Environmental Protection Agency (EPA) criteria PAHs was 6.7 ng/m 3 and around 63% of it was found to be probably carcinogenic to humans. The application of diagnostic ratio and principal component analysis showed vehicular emission as a major source. An increased ratio of ‘combustion PAHs’ to ‘total EPA-PAHs’ during the winter season indicated towards combustion activities. Further, the differences in PAHs concentration were assessed with relation to backward air mass trajectories, which show that the levels of PAHs increase when there is an air mass movement from Central and Western Europe and a fall when the trajectories spend most of their 4-day time over the Atlantic Ocean or in the Arctic region.

Secondhand Smoke: Displaced Enthusiasm?

As evidence mounts that secondhand smoke (SHS) can harm human health, an increasing number of U.S. and Canadian cities are passing bans on smoking in restaurants and bars. Proposed bans have been opposed by a few commercial establishments and their respective trade associations, who fear they may lose clients as a result. Some heating, ventilating, and air-conditioning (HVAC) contractors have suggested that a method called “displacement ventilation” can effectively control SHS, making it unnecessary to impose smoking bans. But a recent study indicates these systems cannot be depended upon to bring SHS down to safe levels. Displacement ventilation systems typically introduce fresh air at or near floor level at a temperature slightly below the desired room temperature. This cooler fresh air displaces the warmer room air at the occupied level; heat and pollutants rise to the ceiling and are drawn out by an exhaust fan. (In comparison, traditional HVAC systems supply air through ceiling vents and recirculate it after diluting it with outdoor air.) A study in the December 2001 issue of Regulatory Toxicology and Pharmacology reported that displacement ventilation can control SHS in smoking areas of restaurants. That study has been used to justify opposing local and provincial smoking ban proposals. Citing various flaws in that study, James Repace, an adjunct professor of public health at Tufts University School of Medicine, and Kenneth Johnson, a research scientist with the Public Health Agency of Canada, undertook their own study of displacement ventilation, which was published in the fall 2006 issue of IAQ Applications. They selected the same establishment used in the 2001 study. The Black Dog Pub housed a smoking bar connected by two pass-through windows and two open doorways to a nonsmoking dining room. Ventilation air was drawn into the nonsmoking area and exhausted out the far corner of the smoking area. Repace and Johnson conducted real-time measurements of particulate polycyclic aromatic hydrocarbons (PPAH), a tobacco smoke carcinogen, and respirable suspended particles (RSP), known to contribute to a variety of respiratory problems. The tests measured PPAH levels of 152 ng/m3 in the Black Dog’s smoking section and 16 ng/m3 in the nonsmoking section. RSP levels of 199 μg/m3 and 40 μg/m3 were recorded in the smoking and nonsmoking areas, respectively. Measurements taken later, after a smoking ban was implemented, showed that levels of RSP and PPAH dropped by 80% and 96%, respectively, in the smoking area, and by 60% and 80% in the non-smoking area. According to Repace, de minimis (i.e., negligible) risk levels of SHS would occur at average RSP concentrations of 0.075 ng/m3 for persons exposed to an average of 8 hours a day over 40 years (PPAH is not regulated). The following year, Repace and Johnson conducted similar tests in two restaurants in Mesa, Arizona. The restaurants were exempt from the city’s nonsmoking ordinance based on their managers’ claims that they could meet smoke-free standards by using displacement ventilation. At Romano’s Macaroni Grill, RSP levels averaged 80 μg/m3 in the smoking bar and 229 μg/m3 in the adjacent nonsmoking restaurant. PPAH levels averaged 304 ng/m3 in the bar and 451 ng/m3 in the restaurant. At T.G.I. Friday’s, RSP levels averaged 205 μg/m3 in the smoking bar and 306 μg/m3 in the nonsmoking restaurant. PPAH levels averaged 13 ng/m3 in the bar and 2 ng/m3 in the restaurant (the latter reflects in part a period during which an outside door was propped open). Based on the nonsmoking sections’ having higher levels of pollutants than the smoking sections, the authors concluded that the ventilation systems in both restaurants were seriously out of balance. However, the Black Dog system, though properly designed and operated, still could not prevent all workers and patrons from being exposed to hazardous levels of SHS. David Sutton, a spokesman for Phillip Morris USA, says he can’t comment on displacement ventilation in particular, but maintains that “in many indoor public places, reasonable ways exist to respect the comfort and choices of both the smoking and nonsmoking adults.” Sutton says establishment owners “should have the flexibility to address the preferences of nonsmokers and smokers through separation, separate rooms, and/or high-quality ventilation.” However, Repace and Johnson concluded that banning smoking is the only way to guarantee a smoke-free indoor environment. “The 2006 Surgeon General’s report states flatly that there is no safe level of SHS exposure,” Repace says. “Displacement ventilation is not a viable substitute for smoking bans in controlling SHS exposure in either designated smoking areas or in contiguous designated nonsmoking areas.” Repace says studies indicate that if you can’t smell tobacco smoke, you are probably not being exposed to a dangerous amount. However, he adds, people with heart conditions or asthma should avoid any place where people are smoking.

Secondhand Tobacco Smoke Exposure and Dose in Boston Bars and Bartenders

TAA1-O-01 Session Title: Indoor Air (I) Introduction: We compare real-time area-monitored air pollution levels from secondhand smoke (SHS) in pubs before and after a smoking ban, estimate nonsmokers' comfort at these SHS levels, and compare area exposure to SHS with urine cotinine dose in bartenders exposed to SHS only at work. Methods: We make real-time measurements of respirable particle (RSP) air pollution and particulate polycyclic aromatic hydrocarbons (PPAH), indoors and outside 7 Boston Massachusetts pubs, before and after a 2003 smoking ban. We assess RSP health risk using the U.S. Air Quality Index (AQI), and SHS odor and irritation intensity using published thresholds. We measure urine cotinine in 73 Boston bartenders exposed to SHS only at work using ELISA assays. Results: Pre-smoking-ban RSP levels average 179 μg/m3 (SD 129 μg/m3); post-ban levels average 7.7 μg/m3 (SD 6.1 μg/m3), yielding SHS-RSP approximately 171 μg/m3. This is of the same order as measured in other recent U.S. studies. This RSP level violates the U.S. annual National Ambient Air Quality Standard (NAAQS) for PM2.5 by 4-fold. Pre-ban indoor PPAH averages, 61.7 ng/m3; post-ban levels average 6.3 μg/m3 (SD 4.0 μg/m3). Post-ban RSP and PPAH levels differ little from outdoor concentrations. Median pre-ban urinary cotinine levels measured in Boston bartenders were 20.7 ng/mL (90% CI, 3–100 ng/mL). Post-ban cotinines were not measured. Discussion and Conclusions: Pre-smoking ban levels of RSP in the Boston pubs are in the Unhealthy to Hazardous range of the AQI. Post-ban, particulate air pollution levels were in the Good range, while carcinogen levels were lower than outdoors. During smoking, SHS odor and irritation thresholds for all pubs averaged were exceeded by factors of 171 and 39, respectively. Assuming 83% of bartenders' SHS exposure came from the workplace, as reported in a recent study in Ireland, Boston bar staff would have a cotinine dose of 17 ng/mL from workplace exposure only, equivalent to an estimated personal RSP exposure from SHS of 539 μg/m3 using a published pharmacokinetic model. By comparing area-monitored SHS-RSP concentrations and SHS-RSP estimated from cotinine, it appears that bartenders' personal SHS exposure is as much as 3 times higher than area monitors indicate due to proximity effects. High levels of SHS in bars indicate significant risk of air pollution diseases and high levels of discomfort for nonsmokers.

Polycyclic aromatic hydrocarbons in Los Angeles air from samples collected on teflon, glass and quartz filters

Levels of ambient particulate polycyclic aromatic hydrocarbons (PAH) have been measured at seven locations in the Los Angeles area using quartz, glass and Teflon filters operated in parallel at the same sampling face velocities. Daytime and night-time samples (12 h each) were collected during summer and winter. Thirteen PAH, from anthracene to coronene, were quantitated in these samples. The measured concentrations (e.g. mean values of 1.62, 0.97, 0.64 and 3.6 ng m −3 for pyrene, chrysene, benzo(a)pyrene and coronene, respectively) suggest that PAH levels in Los Angeles air have not significantly changed during the last decade. For all but one PAH, concentrations measured on glass and quartz filters were lower in 85–90 % of the total number of observations than those measured in samples collected on Teflon filters. On average, glass/Teflon and quartz/Teflon ratios ranged from 0.25 for pyrene to 0.80 for coronene. These observations are of concern since virtually all information available to date concerning airborne PAH has been derived from samples collected on glass filters.