Sediment Soot Radiocarbon Indicates that Recent Pollution Controls Slowed Fossil Fuel Emissions in Southeastern China.

Fossil fuel (FF) combustion emissions account for a large, but uncertain, amount of the soot in the atmosphere, play an important role in climate change, and adversely affect human health. However, historical estimates of FF contributions to air pollution are limited by uncertainties in fuel usage and emission factors. Here, we constrained FF soot emissions from southeastern China over the past 110 years, based on a novel radiocarbon method applied to sedimentary soot. The reconstructed soot accumulations reflect the integrated effects of increased FF use caused by economic development and reductions in emissions due to pollution controls. A sharp increase in FF soot started in 1950 as southeastern China industrialized and developed economically, but decreased FF soot fluxes in recent years suggest that pollution controls reduced soot emissions. We compare FF soot history to changes in CO2 emissions, industrial and economic activities, and pollution controls and show that FF soot fluxes are more readily controlled than atmospheric CO2. Our independent FF soot record provides insights into the effects of economic development and controls on air pollution and the environmental impacts from the changes in soot emissions.

A 150-year record of polycyclic aromatic compound (PAC) deposition from high Andean Cajas National Park, southern Ecuador.

The temporal profiles of polycyclic aromatic compounds (PACs) in lake sediments reflect past changes in emissions, transport and deposition of these pollutants and, thus, record natural and anthropogenic processes. We document fluxes of PACs [(polycyclic aromatic hydrocarbons (PAHs), oxygenated PAHs (OPAHs) and azaarenes (AZAs)] deposited in two tropical high-altitude lakes in the Cajas National Park (Ecuadorian Andes, 2°50'S, 79°10'W). In remote and high elevation Laguna Fondococha (4130m a.s.l.), the temporal fluxes of OPAHs and AZAs were similar to those of PAHs suggesting similar sources. A significant increase of PAC deposition after the 1950s reflects Ecuador's economic development. PAH fluxes were relatively low (∑27PAHs (without retene and perylene): 0.86-11.21ngcm-2yr-1) with a composition pattern typical for long-range atmospheric transport (high 9-fluorenone/fluorene ratios) and biomass burning (30% low molecular weight PAHs). PAHs diagnostic of high temperature combustion (industry, traffic) make up 20-25% of total PAHs. Perylene concentrations increase linearly with increasing sediment depth suggesting diagenetic in-situ production. At lower elevations (Laguna Llaviucu, 3140m a.s.l.) and closer to urban areas, PAC fluxes in the past decades were 4-5 times higher than in the remote high-elevation lake. Laguna Llaviucu also showed higher concentrations of high molecular weight pyrogenic PAHs and a greater diversity of AZAs. Individual OPAHs and AZAs reflect mainly combustion activities. In Laguna Llaviucu, which is at a lower elevation (3140m a.s.l.) and closer to the city, molecular ratios suggest short-range atmospheric transport and deposition of PACs. A very foggy climate (170 rainy days per year) with the precipitation maximum at 3500m removes PACs very efficiently (by wet deposition) from the atmosphere at very short distances from emission sources. This partly explains why L. Llaviucu shows higher fluxes of PACs than the higher elevation L. Fondococha. This study presents the first historical record of organic pollutants from environmental archives in Ecuador.

LabMELD-based organ allocation increases total costs of liver transplantation: a single-center experience.

INTRODUCTION: In 2006, model for end-stage liver disease (MELD)-based allocation was implemented in the Eurotransplant (ET) region. Sick patients, who in general require more resources, are prioritized. In this analysis, the effect of MELD on costs for liver transplantation (LTx) was assessed. METHODS: Total costs for LTx before and after implementation of MELD were identified in 256 patients from January 2005-December 2007. Forty-nine patients (Re-LTx, HU listings, and 30-d mortality) were excluded from further analysis. The costs of LTx in 207 patients have been correlated with their corresponding labMELD; 84 and 123 LTx before and after implementation of MELD were compared, and patient survival was monitored. RESULTS: A positive correlation exists between labMELD and costs (r(2) = 0.28; p < 0.05). Only nominal correlation existed between the Child-Pugh classification and costs. The labMELD scores can be stratified into four groups (I: 6-10, II: 11-18, III: 19-24, and IV: >24), with an increase of €15.672 ± 2.233 between each group (p < 0.05). Recipients' labMELD at the time of LTx increased significantly in the MELD-based allocation system. Costs increased by €11.650/patient (p < 0.05), while median survival decreased from 1219 to 869 d (p < 0.05). CONCLUSION: LabMELD-based allocation increased total costs of LTx. In accordance with other studies, the sickest patients need the most resources.

Cost distribution of orthotopic liver transplantation: single-center analysis under DRG-based reimbursement.

Costs of orthotopic liver transplantation (OLT) are influenced by multiple factors. Surgeons must be interested in determining the probability of meeting the projected cost averages. Costs of procedures, labor, drugs and pharmaceuticals, materials, and overhead costs of infrastructure were calculated during the primary stay in 38 consecutive patients undergoing OLT at a single center. Endpoint of cost aggregation was discharge from acute care. Costs per patient were grouped to plot the cost density distribution function. Mean cost of OLT was 49,000. Costs showed a large variation, ranging from 18,000 to 189,000 per case. Most patients were grouped in the G-DRG-A01C split (n=31), which characterizes the least resource consumptive split. Costs of OLT were not normally distributed. There was a left-skewed beta-distribution of costs. Labor-related costs were responsible for the largest cost fraction (mean 42.9%), whereas drugs and medication accounted for 24.9% on average. Most patients could be transplanted within cost groups below 50,000. The marked cost heterogeneity after OLT suggests that primarily medical comorbidities are of relevance for extraordinary resource consumption. A minimum number of transplants should be performed in single institutions to improve chances to financially counterbalance higher costs of individual cases under DRG-based reimbursement. Small programs have to bear increased risks of financial distortion. The asymmetry of cost distribution after OLT should be taken into account in future reimbursement regulations.