Role of wastewater treatment plant (WWTP) in environmental cycling of poly- and perfluoroalkyl (PFAS) compounds

The role of wastewater treatment plants (WWTP) in environmental cycling of poly- and perfluoroalkyl substances (PFASs) through aqueous effluent, sludge and air emission has been critically reviewed here. Understanding the role of WWTPs can provide better understanding of global cycling of persistent PFASs and assist in formulating relevant environmental policies. The review suggests that WWTP effluent is a major source of perfluoroalkyl acids (PFAAs) in surface water. Land application of biosolids (treated sludge) has shown preferential bioaccumulation of short chain (<C7) PFAAs in various plant compartments, leading to possible contamination of the food cycle. Elevated air concentration (1.5 to 15 times) of ΣPFASs have been reported at the aeration tanks on WWTP sites, compared to reference sites not contaminated with WWTP emission. The air emission of neutral PFASs has important implications considering the long-range transport and subsequent degradation of neutral compounds leading to the occurrence of recalcitrant PFAAs in pristine remote environments. Research gap exist in terms of fate of polyfluroalkyl compounds (neutral PFASs) during wastetwater treatment and in aquatic and terrestrial environment. Considering the wide range of commercially available PFASs, measuring only perfluorocarboxylic acid (PFCA) and perfluorosulfonic acid (PFSA) can lead to underestimation of the total PFAS load derived from WWTPs. Knowledge of the various pathways of PFAS from WWTPs to receiving environments, outlined in this study, can help in adopting best possible management practices to reduce the release of PFASs from WWTPs

Novel fungal consortium pretreatment of waste oat straw to enhance economic and efficient biohydrogen production

Bio-pretreatment using a fungal consortium to enhance the efficiency of lignocellulosic biohydrogen production was explored. A fungal consortium comprised of T. viride and P. chrysosporium as microbial inoculum was compared with untreated and single-species-inoculated samples. Fungal bio-pretreatment was carried out at atmospheric conditions with limited external energy input. The effectiveness of the pretreatment is evaluated according to its lignin removal and digestibility. Enhancement of biohydrogen production is observed through scanning electron microscopy (SEM) analysis. Fungal consortium pretreatment effectively degraded oat straw lignin (by >47% in 7 days) leading to decomposition of cell-wall structure as revealed in SEM images, increasing biohydrogen yield. The hydrogen produced from the fungal consortium pretreated straw increased by 165% 6 days later, and was more than produced from either a single fungi species of T. viride or P. chrysosponium pretreated straw (94% and 106%, respectively). No inhibitory effect on hydrogen production was observed

Sorption of DOM and hydrophobic organic compounds onto sewage-based activated carbon

Treatment of stormwater via sorption has the potential to remove both colloidal and dissolved pollutants. Previous research shows that activated carbon produced from sewage sludge is very efficient in sorbing hydrophobic organic compounds (HOCs), frequently detected in stormwater. The aim of this research was to determine whether the presence of dissolved organic matter (DOM) has a negative effect on the adsorption of HOCs onto sludge-based activated carbon (SBAC) in batch adsorption tests. Batch adsorption tests were used to investigate the influence of two types of DOM – soil organic matter and humic acid (HA) technical standard – on the sorption of HOCs onto SBAC, and whether preloading adsorbent and adsorbates with DOM affects HOC sorption. The results indicate that soil DOM and HAs do not have a significant negative effect on the adsorption of HOCs under tested experimental conditions, except for a highly hydrophobic compound. In addition, preloading SBAC or HOCs with DOM did not lead to lower adsorption of HOCs. Batch adsorption tests appear to be inefficient for investigating DOM effects on HOC adsorption, as saturating the carbon is difficult because of high SBAC adsorption capacity and low HOC solubility, so that limited competition occurs on the sorbent

Adsorption of Organic Stormwater Pollutants onto Activated Carbon from Sewage Sludge

Adsorption filters have the potential to retain suspended pollutants physically, as well as attracting and chemically attaching dissolved compounds onto the adsorbent. This study investigated the adsorption of eight hydrophobic organic compounds (HOCs) frequently detected in stormwater e including four polycyclic aromatic hydrocarbons (PAHs), two phthalates and two alkylphenols e onto activated carbon produced from domestic sewage sludge. Adsorption was studied using batch tests. Kinetic studies indicated that bulk adsorption of HOCs occurred within 10 min. Sludge-based activated carbon (SBAC) was as efficient as tested commercial carbons for adsorbing HOCs; adsorption capacities ranged from 70 to 2800 mg/g (Cinitial ¼ 10e300 mg/L; 15 mg SBAC in 150 mL solution; 24 h contact time) for each HOC. In the batch tests, the adsorption capacity was generally negatively correlated to the compounds' hydrophobicity (log Kow) and positively associated with decreasing molecule size, suggesting that molecular sieving limited adsorption. However, in repeated adsorption tests, where competition between HOCs was more likely to occur, adsorbed pollutant loads exhibited strong positive correlation with log Kow. Sewage sludge as a carbon source for activated carbon has great potential as a sustainable alternative for sludge waste management practices and production of a high-capacity adsorption material

Power, Prestige, and Wealth: Indiana’s 1998 Award-winning School Districts

This research examines relationships between the Blue Ribbon school awards of 1998-1999 in Indiana and their per pupil expenditure, their local monetary sources, and their self-reports evidencing power, prestige, and wealth. An earlier study of 1994-1996 middle and high schools in Indiana found that total local funds were significantly greater in Blue Ribbon school districts than in non-Blue Ribbon school districts. Part of the conclusion suggested a follow up study of subsequent years. The ensuing report seeks to determine if school districts chosen for Blue Ribbon awards in 1998-1999 had greater local sources, or greater total expenditures per pupil, than non-Blue Ribbon school districts did. Did Blue Ribbon School districts spend more local funds than non Blue Ribbon School districts did? Did Blue Ribbon School districts spend more total (federal, state, and local) funds than non Blue Ribbon School districts did? A discussion related to the power, prestige, and wealth of the award-winning elementary schools follows the presentation of the findings

Enhanced biohydrogen production from oat straw co-digested with cow dung / sewage sludge by combined aerobic digestion and anaerobic fermentation

Hydrogen was produced from oat straw by combined aerobic and anaerobic fermentation with fungi and cow dung. With aerobic pre-digestion, the maximum hydrogen production rate reached 133 ml/g volatile suspended solids per hour. The maximum hydrogen yield was 71.5 ml/g straw in 6 days by biological process. The lignocellulosic conversion of oak-straw waste was 39%, with the complex component converting 68% of the hemi-cellulose and 61% of the cellulose, but only 34% of lignin conversion. Aerobic pre-digestion by Trichoderma viride and Saccharomyces cerevisiae was significantly effective for lignin degradation. Combining aerobic and anaerobic fermentation is a promising low-cost efficient and environmentally friendly method, compared with hydrogen fermentation, not only for hydrogen production, but also for converting straw biomass

Fibulin-2: genetic mapping and exclusion as a candidate gene in Marfan syndrome type 2.

International audienceFibulin-2 (FBLN2) is a new extracellular matrix protein that has been considered a candidate gene for Marfan syndrome type 2 (locus MFS2) based on chromosomal colocation at 3p24.2-p25 and disease phenotype. In the absence of polymorphic markers reported for FBLN2, direct sequencing of the gene was performed and two intragenic polymorphisms were identified. Linkage was excluded between FBLN2 and the MFS2 gene. Furthermore, two-point lod scores were generated between these markers and anonymous markers arrayed on the genetic map of 3p and closely linked to MFS2. These analyses placed FBLN2 at marker D3S1585

Novel insights into chromosome evolution in birds, archosaurs, and reptiles

Homologous synteny blocks (HSBs) and evolutionary breakpoint regions (EBRs) in mammalian chromosomes are enriched for distinct DNA features, contributing to distinct phenotypes. To reveal HSB and EBR roles in avian evolution, we performed a sequence-based comparison of 21 avian and 5 outgroup species using recently sequenced genomes across the avian family tree and a newly-developed algorithm. We identified EBRs and HSBs in ancestral bird, archosaurian (bird, crocodile, and dinosaur), and reptile chromosomes. Genes involved in the regulation of gene expression and biosynthetic processes were preferably located in HSBs, including for example, avian-specific HSBs enriched for genes involved in limb development. Within birds, some lineage-specific EBRs rearranged genes were related to distinct phenotypes, such as forebrain development in parrots. Our findings provide novel evolutionary insights into genome evolution in birds, particularly on how chromosome rearrangements likely contributed to the formation of novel phenotypes