A study of the relationship between rear-of-wheel particle emissions and close-proximity tire/road noise of a passenger car.

Non-exhaust particulate emissions and road traffic noise will continue to constitute significant threats to the environment and human health during the 21st century. In the EU alone, >60 million adults are subjected to unhealthy levels of vehicle noise, while over 200,000 premature deaths are caused by chronic exposure to excessive concentrations of fine particles, with road traffic being a key source. Although these pollutants share common sources and can affect the same targets, studies have often treated their emissions separately. This study establishes both the phenomenological and mathematical relationships between tire/road noise (TRN) and rear-of-wheel particle (RoWP) emissions. Information from test track measurements, coupled with correlation-based models, enables linking TRN with RoWP emissions through variables such as vehicle speed and pavement properties, including macro-texture scales. A careful examination of the data reveals that pavement macro-texture acts as a crucible in which TRN and RoWP emissions are generated in an interrelated manner. However, at speeds over 70-80 km/h, the depletion of readily mobilizable RoWP fractions, followed by the emergence of refractory (hard-to-mobilize) circum-/super-micron RoWP fractions from resuspension (which accompanies the intensification of air-pumping TRN generation mechanisms), marks a loss of this interdependence. These results, supplemented by valuable insights into the particulate emission performance of pavements, serve to outline future air quality challenges and provide a basis for the simplified monitoring and control (e.g. through acoustic measurements) of RoWP emissions.

In-line measurement of exhaust mercury emissions by an instrumented light-duty vehicle using both on-road and test track experiments.

The initial purpose of this study has been to develop an instrumental platform for monitoring mercury (Hg) emissions from vehicle exhausts under actual traffic conditions. The platform was then mounted onto a fully-instrumented passenger car to identify emission proxies and factors governing the emissions of gaseous elemental Hg (GeM) and its complementary fraction (GdPM). Data obtained from the road were complemented by data acquired on a test track at either stabilized speeds or well-characterized speed variations. GeM emissions increased overall with both driving speed and fuel consumption; nonetheless, they were influenced by the sequence of accelerations and duration associated with the preceding idling or low-speed driving situations. GdPM emissions varied considerably over the course of trips or track tests, with medians ranging from 7% to 70% of the total Hg emissions stemming from fuel. Such high percentages could be explained by a series of redox reactions, whose kinetics and yield were influenced as much by exhaust gas temperature as by driving conditions or the exhaust system structural configuration. Lastly, an analysis of the GeM and GdPM signals showed that urban cores constitute emission hotspots during rush hour when handling low-speed driving and stop-and-go traffic.

Cost-Effectiveness of Bosutinib for the Treatment of Adult Patients with Chronic Phase Chronic Myeloid Leukemia in the Second-Line Setting.

BACKGROUND: A recently conducted matching-adjusted indirect comparison demonstrated that bosutinib improved progression-free survival, and delayed progression to advanced disease compared with dasatinib and nilotinib in patients with second line (2L) chronic-phase chronic myeloid leukemia (CP-CML). However, the long-term clinical and economic impact of using bosutinib versus dasatinib and nilotinib has not been evaluated. The objective was to determine the cost-effectiveness of bosutinib compared with dasatinib and bosutinib compared with nilotinib from a US payer perspective. METHODS: A cost-effectiveness model was developed using partition survival methods and three health states: progression-free, progression, and death. Trial data (individual patient-level and aggregate-level data) informed the progression-free and overall survival estimates. Costs included drugs and medical resource use. Utility values were obtained from literature. Sensitivity analyses (SAs) included one-way and probabilistic sensitivity analyses (PSAs). RESULTS: Comparing bosutinib versus dasatinib resulted in a gain of 0.4 discounted life years, 1.5 quality-adjusted life years (QALYs), and incremental costs of $28,459 (values in 2020 US dollars), for an incremental cost-effectiveness ratio (ICER) of $19,811/QALY gained. Comparing bosutinib versus nilotinib resulted in a gain of 0.8 discounted life-years, 1.8 QALYs, and incremental costs of $76,563, for an ICER of $41,932/QALY gained. Drug costs and extrapolation distribution type were the main drivers of the model in the one-way SAs. In the PSAs, bosutinib had >90% and >80% probabilities of being cost-effective at a willingness-to-pay threshold of $100,000/QALY versus dasatinib and nilotinib, respectively. CONCLUSIONS: Our results suggest that compared with dasatinib and nilotinib, bosutinib may represent good value for money for treating 2L CP-CML patients.

Assessment of palladium footprint from road traffic in two highway environments.

Palladium (Pd) is an emerging eco-toxic pollutant from vehicle catalytic converters, emitted worldwide for more than two decades. Nowadays, the spatial extent of Pd fallout is growing along roads, but its subsequent fate in neighboring terrestrial ecosystems has not been extensively addressed yet. Two sites representative of contrasted natural environments (field, forest) but located under similar ambient conditions were selected to isolate and analyze the specific impact of vehicular Pd, along highway A71, France. Pd impregnation was assessed along 200-m-long transects perpendicular to the highway. Contents were measured in soils, earthworms, plant communities of the right of way (ROW), and the neighboring field (crop weeds), as well as in a moss, and bramble and ivy leaves in the forest. The direct impact of Pd fallouts appears to be confined in the grassy verge of the highway: ROW soils ([Pd] = 52-65 ng g(-1)), earthworms ([Pd] = 18-38 ng g(-1)), and plant community ([Pd] = 10-23 ng g(-1)). Pd footprint is pointed out by the accumulation index calculated for earthworms and plant communities even though transfer coefficients indicate the absence of bioaccumulation (TCs < 1). An indirect longer range transfer of Pd is identified, induced by hydric transport of organic matter.

Fate and spatial variations of polybrominated diphenyl ethers in the deposition within a heavily urbanized area: case of Paris (France).

In this paper, we present the first results on the geochemical cycle of PolyBrominated Diphenyl Ethers (or PBDE) in the Paris Region (France). In order to provide information about the distribution and mobility of eight PBDE congeners, we first determined the level of contamination of different environmental compartments: i.e. atmosphere, soils and waters. Atmospheric PBDE deposition was estimated from a site located in the centre of Paris. Surface soils (0-10 cm) were collected from multiple wooded, rural and urban locations through the Paris Region (12,000 km²). To complete our investigation, we measured PBDE concentrations/contents in the runoff from an urban catchment and settleable particles from the Seine River. Hence, gained results showed that in the superficial soils, the highest concentrations of highly brominated congeners were measured in the vicinity of the most urbanized areas whereas less brominated congeners were widespread in the whole Paris Region. This could be explained by the higher affinity of highly brominated congeners for the solid phase substrata coupled with the fact that the atmospheric deposition occurred mainly through particle deposition (close to 90% of the total atmospheric deposition). To the opposite, the less brominated congeners from the superficial soils were readily transferred to the dissolved phase of runoff and could reach more distant terrestrial and aquatic systems. Finally, a mass transfer was established at the scale of the Paris metropolitan city (105 km²). It showed that the cycle of PBDE in this particular urban area is highly dynamic with multiple sources and sinks, and rapid transfers between the ecosystem compartments.

Mercury speciation and exchanges at the air-water interface of a tropical artificial reservoir, French Guiana.

The distribution and speciation of mercury (Hg) in air, rain, and surface waters from the artificial tropical lake of Petit-Saut in French Guiana were investigated during the 2003/04 period. In the air, total gaseous mercury (TGM) at the dam station averaged 12+/-2 pmol m(-3) of which >98% was gaseous elemental mercury (GEM). GEM distribution depicted a day-night cycling with high concentrations (up to 15 pmol m(-3)) at dawn and low concentrations (down to 5 pmol m(-3)) at nightfall. Reactive gaseous mercury (RGM) represented <1% of the GEM with a mean concentration of 4+/-3 fmol m(-3). Diel RGM variations were negatively related to GEM. In the rain, the sum of all Hg species in the unfiltered (HgT(UNF)) averaged 16+/-12 pmol L(-1). Temporal distribution of HgT(UNF) exhibited a pattern of high concentrations during the late dry seasons (up to 57.5 pmol L(-1)) and low concentrations (down to 2.7 pmol L(-1)) in the course of the wet seasons. Unfiltered reactive (HgR(UNF)), dissolved gaseous (DGM) and monomethyl (MMHg(UNF)) Hg constituted 20, 5 and 5% of HgT(UNF), respectively. All measured Hg species were positively related and displayed negative relationships with the pH of the rain. In the reservoir surface waters, dissolved total mercury (HgT(D)) averaged 3.4+/-1.2 pmol L(-1) of which 10% consisted of DGM. DGM showed a trend of high concentrations during the dry seasons (480+/-270 fmol L(-1)) and lower (230+/-130 fmol L(-1)) in the course of the wet seasons. Diel variations included diurnal photo-induced DGM production (of about 60 fmol L(-1) h(-1)) coupled to minute to hour oxidation/reduction cycles (of >100 fmol L(-1) amplitude). Finally, calculated atmospheric Hg inputs to the Petit-Saut reservoir represented 14 mol yr(-1) whereas DGM evasion reached 23 mol yr(-1). Apportionment among forms of Hg deposition indicated that up to 75% of the total Hg invasive flux follows the rainfall pathway.

Formation of dissolved gaseous mercury in a tropical lake (Petit-Saut reservoir, French Guiana).

Formation of dissolved gaseous mercury (DGM) and its volatilization from aquatic systems can be considered as a natural attenuation process, which limits the methylation of mercury (Hg) and Hg accumulation in fish. Although gold-mining activity and erosion of tropical soils lead to increased Hg concentration in aquatic systems, little is known about DGM production and distribution in tropical aqueous systems. Our work explores the vertical distribution and principal sources of DGM in a meromictic Amazonian reservoir. Dissolved gaseous mercury measurements carried out in Petit-Saut reservoir (French Guiana, South America) revealed DGM increase in the surface waters and at the bottom layers of the reservoir during the dry season. As in arctic and temperate lakes, high DGM concentrations in surface waters were attributed to sunlight-mediated photochemical processes. Dissolved gaseous mercury concentrations in the anaerobic hypolimnion were larger than in temperate or arctic lakes. In order to elucidate Hg(II) reduction pathways in the bottom layer of tropical reservoir, laboratory Hg(II) reduction experiments were performed with anoxic aqueous suspensions of surface sediments either untreated or treated by gamma-ray and NaN3. Our results indicated that DGM production at the bottom layer of Petit-Saut reservoir was biologically mediated. Dissolved gaseous mercury formation rates in the surface sediment suspensions were of the same order of magnitude as formation rates in freshwater lakes reported in literature.