Different collector types for sampling deposition of polycyclic aromatic hydrocarbons--comparison of measurement results and their uncertainty.

Different collector types, sample workup procedures and analysis methods to measure the deposition of polycyclic aromatic hydrocarbons (PAH) were tested and compared. Whilst sample workup and analysis methods did not influence the results of PAH deposition measurements, using different collector types changed the measured deposition rates of PAH significantly. The results obtained with a funnel-bottle collector showed the highest deposition rates and a low measurement uncertainty. The deposition rates obtained with the wet-only collectors were the lowest at industrial sites and under dry weather conditions. For the open-jar collectors the measurement uncertainty was high. Only at an industrial site with extremely high PAH deposition rates the results of open-jar collectors were comparable to those obtained with funnel-bottle collectors. Thus, if bulk deposition of PAH has to be measured, funnel-bottle combinations are proved to be the collectors of choice. These collectors were the only ones always fulfilling the requirements of European legislation.

Artificial-turf playing fields: contents of metals, PAHs, PCBs, PCDDs and PCDFs, inhalation exposure to PAHs and related preliminary risk assessment.

The artificial-turf granulates made from recycled rubber waste are of health concern due the possible exposure of users to dangerous substances present in the rubber, and especially to PAHs. In this work, we determined the contents of PAHs, metals, non-dioxin-like PCBs (NDL-PCBs), PCDDs and PCDFs in granulates, and PAH concentrations in air during the use of the field. The purposes were to identify some potential chemical risks and to roughly assess the risk associated with inhalation exposure to PAHs. Rubber granulates were collected from 13 Italian fields and analysed for 25 metals and nine PAHs. One further granulate was analysed for NDL-PCBs, PCDDs, PCDFs and 13 PAHs. Air samples were collected on filter at two fields, using respectively a high volume static sampler close to the athletes and personal samplers worn by the athletes, and at background locations outside the fields. In the absence of specific quality standards, we evaluated the measured contents with respect to the Italian standards for soils to be reclaimed as green areas. Zn concentrations (1 to 19 g/kg) and BaP concentrations (0.02 to 11 mg/kg) in granulates largely exceeded the pertinent standards, up to two orders of magnitude. No association between the origin of the recycled rubber and the contents of PAHs and metals was observed. The sums of NDL-PCBs and WHO-TE PCDDs+PCDFs were, respectively, 0.18 and 0.67×10(-5) mg/kg. The increased BaP concentrations in air, due to the use of the field, varied approximately from <0.01 to 0.4 ng/m(3), the latter referring to worst-case conditions as to the release of particle-bound PAHs. Based on the 0.4 ng/m(3) concentration, an excess lifetime cancer risk of 1×10(-6) was calculated for an intense 30-year activity.

On-filter degradation of particle-bound benzo[a]pyrene by ozone during air sampling: a review of the experimental evidence of an artefact.

On-filter loss of benzo[a]pyrene (BaP) during air sampling due to reaction with ozone was observed in several experimental studies. It was also of concern in the recent CEN method for BaP measurement in ambient air: a denuder-based sampling system minimising this loss is described in the method but, due to the scarcity of validated data, is not yet ready to be used for normative purposes. This paper presents a review of the available experimental results on this artefact, as reported in 16 published studies, with the aim of assessing the state of knowledge regarding its occurrence and extent. Almost all field studies showed that, regardless the type of sampling site, the on-filter BaP degradation by O(3) constituted a not negligible artefact. When limiting the analysis of the results to the field sampling campaigns carried out under real-world conditions, mean BaP losses were typically in the 20-55% range (hence causing underestimates of mean BaP concentrations possibly in the order of 100%), with daily maxima up to 71%. The duration of the campaigns was typically of a few days; no experimental results are available on the actual O(3) effect on the BaP annual mean. Various factors were investigated as potential contributors to the O(3) effect, although their role has yet to be clarified: O(3) concentration, relative humidity, distance from BaP sources, size distribution and source of particles, sampling duration. The use of denuders for O(3) removal in the sampling system substantially eliminates this artefact, but their application and performance must still be validated.

Atmospheric pollution by PAHs, PCDD/Fs and PCBs simultaneously collected at a regional background site in central Italy and at an urban site in Rome.

Concentrations of PAHs and PCDD/Fs were measured throughout one year, and PCBs during the second semester, at a rural site in a natural park representative of background pollution in central Italy; results were compared with simultaneous measurements performed at an urban site in Rome 60km away. Twenty-four daily samples were collected at each site by a high-volume PM(10) sampler from February 2000 to January 2001. After ultrasonic extraction and clean-up by TLC, samples were analysed by GC-MS. Mean concentrations of benzo[a]pyrene (BaP, as a marker of carcinogenic PAHs), summation operatorPCDD/Fs and summation operator64 PCBs in Rome were, respectively: 1.1ngm(-3), 65fgWHO-TEQm(-3), 553pgm(-3). The background concentrations were, respectively: 0.016ngm(-3), 3fgWHO-TEQm(-3), and 94pgm(-3). Hence, BaP, and the other PAHs, showed the highest urban-background gradient (two orders of magnitude) and PCBs the lowest. The background pollution levels of BaP and PCDD/Fs were in agreement with the few available background/remote measurements in Europe. In Rome PAHs and PCBs, but not PCDD/Fs, were clearly seasonal; the PCDD/F TEQ was moderately correlated with BaP (P<0.001). At the background site, the seasonality of PAHs was less marked, while it could not be assessed for PCDD/Fs and PCBs. The PCB TEQ accounted for 4% and 15% of total (PCDD/Fs+PCBs) TEQ at the urban and background site, respectively. Mean PM(10) concentration was 54microgm(-3) in Rome and 15microgm(-3) at the background site.

Occurrence of PCDD/Fs in urban air before and after the ban of leaded gasoline.

The source of PCDDs and PCDFs in automotive exhaust is not yet fully explained. The chlorinated hydrocarbons used in the formulation of lead-alkyl additives were suspected as a possible major source. Based on this, the decreasing use of leaded gasoline followed by its final ban (occurred on 1/1/2002, in Italy) should have resulted in a decreasing presence of PCDD/Fs in urban air and possibly some differences in their profile. To investigate these aspects, we monitored PCDD/Fs for one year starting in September 2001, at a medium-traffic road site in Rome, with weekly frequency. Results were then compared with those obtained in a previous study performed before the ban (from February 2000 to January 2001) at the same site. As compared with the previous study, the yearly-averaged overall PCDD/F concentration, as toxic equivalent of 2,3,7,8-TCDD, decreased from 60 to 50 fg m(-3) I-TEQ; it remained unchanged, however, if one sample with a particularly high PCDD/F content was excluded from each data set. The monthly trend confirmed the one found in the former study. On an annual basis, the two mean congener profiles were almost identical. The concentration levels and the constancy of profiles, as calculated for the two periods, do not support the hypothesis of a major role of leaded gasoline, substantially different from unleaded one, in contributing to PCDD/F air pollution.