The recent article by Luu et al. (1) predicting an excess lifetime risk from polyurethane covered breast implants of 1 in 400,000 is based upon numerous questionable assumptions and cannot go unchallenged. I have listed below several of the more obvious problems with this study and its conclusions. The estimated dose of polyurethane was too high. The authors use a weight of foam in their dosage...

In the present paper, the sorption properties of caffeine (CAF) onto polyether type polyurethane foam (PUF) as solid phase sorbent were investigated with UV determination at 274.3 nm. Batch and column methods were used to optimize chemical, flow, kinetic and isothermal conditions for preconcentration of CAF. Results indicated quantitative sorption of CAF at pH 8 and 30 min shaking time. The max...

PURPOSE The aim of this study was to assess the feasibility of biodegradable polyurethane (PU) foam for closure of oroantral communications (OACs). PATIENTS AND METHODS Ten consecutive patients with OACs (existing <24 hours) were treated with PU foam. Standardized evaluations were performed at 2 weeks and 8 weeks after closure of the OAC. RESULTS In 5 patients, the OACs were closed successf...

Flexible and semi-rigid polyurethane foams have been widely used in automotive interior parts, residential upholstered furniture and bedding. In these, as well as other end use industries, a reduction of Volatile Organic Compounds (VOCs) emissions from polyurethane foams continues to be an important issue [1, 2]. To address this challenge, reactive amine catalysts, which have an active hydrogen...

Alcaligenes latus, isolated from industrial effluent, was able to grow in mineral salts medium with 50 ppm (0.15 mM) of H-acid as a sole source of carbon. Immobilization of Alcaligenes latus in Ca-alginate and polyurethane foam resulted in cells embedded in the matrices. When free cells and immobilized cells were used for biodegradation studies at concentration ranging from 100 ppm (0.3 mM) to ...

In present day scenario, pesticides are widely used for pest control in agriculture, because of which, the drinking water sources (both surface and ground water) gets contaminated. Majority of the pesticides are defiant to biodegradation and are found to be carcinogenic in nature even at trace levels. Various conventional methods employed for removal of pesticide are surface adsorption, photo-c...

This paper reports the results of applying anaerobic sequencing batch biofilm reactors (AnSBBR) for treating sulfate-rich wastewater. The reactor was filled with polyurethane foam matrices or with eucalyptus charcoal, used as the support for biomass attachment. Synthetic wastewater was prepared with two ratios between chemical oxygen demand (COD) and sulfate concentration (COD/SO4) of 0.4 and 3...

After immobilization of anaerobes on polyurethane foam in a thermophilic, fixed-bed, anaerobic digester supplied with acetate, the results of real-time PCR analysis indicated that the major immobilized methanogenic archaea were Methanosarcina spp., and that the major free-living methanogenic archaea were Methanosarcina and Methanobacterium spp. 16S rRNA gene densities of Methanosarcina spp. and...

A computational study has been carried out to investigate smouldering ignition and propagation in polyurethane foam. The one-dimensional, transient, governing equations for smouldering combustion in a porous fuel are solved accounting for improved solid-phase chemical kinetics. Forward and opposed smouldering modes are examine and the model describes well both propagation modes. Specifically, t...