Morphological Changes in Poly(Caprolactone)/Poly(Vinyl Chloride) Blends Caused by Biodegradation

The biodegradation of blends of poly(caprolactone) (PCL) and poly(vinyl chloride) (PVC) has been studied. Blends of composition PCL/PVC 1:1 and 1:2 w/w were tested. The 1:1 blend contained crystals in the as-cast state and became more crystalline on exposure to different bio-active agents. The 1:2 blend was amorphous in the as-cast state but developed a significant crystal component after 4 months exposure to the bio-agents. Three bio-active agents were used and all were found to produce qualitatively similar behaviour but their activity was somewhat different. For both the 1:1 blend and the 1:2 blend the ranking of the three bio-active agents tested, in increasing order, was Curvularia sp.; Trogia buccinalis; Phanerochaete chrysosporium.     

Analysis of per- and polyfluorinated alkyl substances in air samples from Northwest Europe

Air samples were collected from 4 field sites in Europe: 2 sites from the UK, Hazelrigg (semi-rural) and Manchester (urban); 1 site from Ireland: Mace Head (rural); and 1 site from Norway: Kjeller (rural). Additionally, air samples were taken from indoor locations in Troms?, Norway. Air samples were collected using high-volume air samplers employing sampling modules containing glass-fibre filters (GFFs, particle phase), and glass columns with a polyurethane foam (PUF)-XAD-2-PUF sandwich (gaseous phase). Typical outdoor air volumes required for the determination of per- and polyfluorinated alkyl substances (PFAS) ranged from 500-1800 m3. GFFs and PUF-XAD columns were analysed separately to obtain information on phase partitioning. All air samples were analysed for volatile, neutral PFAS, with selected GFF samples halved for analysis of both neutral and airborne particle-bound ionic PFAS. Volatile PFAS were extracted from air samples by cold-column immersion with ethyl acetate, and were analysed by gas chromatography-mass spectrometry in the positive chemical ionisation mode (GC-PCI-MS). Ionic PFAS were extracted from GFFs by sonication in methanol, and were analysed by liquid chromatography-time-of-flight-mass spectrometry (LC-TOF-MS) using electrospray ionisation in the negative ion mode (ESI-). Perfluorooctanoate (PFOA) was often the predominant analyte found in the particulate phase at concentrations ranging from 1-818 pg m(-3), and 8:2 fluorotelomer alcohol (FTOH) and 6:2 FTOH were the prevailing analytes found in the gas phase, at 5-243 pg m(-3) and 5-189 pg m(-3), respectively. These three PFAS were ubiquitous in air samples. Many other PFAS, both neutral and ionic, were also present, and levels of individual analytes were in the 1-125 pg m(-3) range. Levels of some PFAS exceeded those of traditional persistent organic pollutants (POPs). In this study, the presence of 12:2 FTOH and fluorotelomer olefins (FTolefins), and ionic PFAS other than perfluorooctane sulfonate (PFOS) and PFOA, are reported in air samples for the first time. Concentrations of neutral PFAS were several orders of magnitude higher in indoor air than outdoor air, making homes a likely important diffuse source of PFAS to the atmosphere. Our repeated findings of non-volatile ionic PFAS in air samples raises the possibility that they might directly undergo significant atmospheric transport on particles away from source regions, and more atmospheric measurements of ionic PFAS are strongly recommended.     

Chemical monitoring of river water bodies in an EU outermost region: examples from the Azores archipelago (Portugal)

Chemical monitoring of water quality on a total of 16 rivers in the Azores archipelago (Portugal), since 2003, made it possible to identify the major pressures and spatial geochemical variations along main course of the rivers. River water pollution is to a large extent associated to point sources, namely domestic wastewater discharges, especially in urban areas, and diffuse sources, associated with pasture land, and explain the high values on BOD(5) and nutrients (P and N). Heavy metals and metalloids, as well as hydrocarbons and pesticides, are generally under the detection limits of the analytical methods. Generally, river water reflects pollution loads according to a simple model, derived from land use in the watershed: in the upper part conditions are pristine, in the intermediate portion of the basin pasture land dominates and near the coast urban discharges are increasingly important. Results stress the role that an approach based on the watershed scale, coupled with land use management measures, are crucial to water management procedures and a successful WFD implementation in small river basin districts like the Azores. The paper also shows the need for full compliance regarding EU directives on urban wastewater and nitrate pollution due to agriculture.     

Assessment of indoor airborne contamination in a wastewater treatment plant

The main objective of this work was to quantify and characterize the major indoor air contaminants present in different stages of a municipal WWTP, including microorganisms (bacteria and fungi), carbon dioxide, carbon monoxide, hydrogen sulfide ammonia, formaldehyde, and volatile organic compounds (VOCs). In general, the total bacteria concentration was found to vary from 60 to >52,560 colony-forming units (CFU)/m³, and the total fungi concentration ranged from 369 to 14,068 CFU/m³. Generally, Gram-positive bacteria were observed in higher number than Gram-negative bacteria. CO₂ concentration ranged from 251 to 9,710 ppm, and CO concentration was either not detected or presented a level of 1 ppm. H₂S concentration ranged from 0.1 to 6.0 ppm. NH₃ concentration was <2 ppm in most samples. Formaldehyde was <0.01 ppm at all sampling sites. The total VOC concentration ranged from 36 to 1,724 μg/m³. Among the VOCs, toluene presented the highest concentration. Results point to indoor/outdoor ratios higher than one. In general, the highest levels of airborne contaminants were detected at the primary treatment (SEDIPAC 3D), secondary sedimentation, and sludge dehydration. At most sampling sites, the concentrations of airborne contaminants were below the occupational exposure limits (OELs) for all the campaigns. However, a few contaminants were above OELs in some sampling sites.     

Elaeis guineensis-activated carbon for methylene blue removal: adsorption capacity and optimization using CCD-RSM

Environment, Development and Sustainability - The activated biochar is a carbonaceous material obtained from thermal degradation of biomass with high adsorption potential. On the other hand, the...     

Generating Co-Management at Kasha Katuwe Tent Rocks National Monument,New Mexico

Collaborative planning theory and co-management paradigms promise conflict prevention and the incorporation of indigenous knowledge into plans. Critics argue that without devolved power to culturally legitimate institutions, indigenous perspectives are marginalized. Co-management practice in North America is largely limited to treaty-protected fish and wildlife because federal agencies cannot devolve land management authority. This paper explores why the Pueblo de Cochiti, a federally recognized American Indian Tribe, and the U.S. Bureau of Land Management sustained an rare joint management agreement for the Kasha-Katuwe Tent Rocks National Monument in New Mexico despite a history of conflict over federal control of customary tribal lands that discouraged the Pueblo from working with federal agencies. Based on the participant interviews and documents, the case suggests that clear agreements, management attitudes, and the direct representation of indigenous forms of government helped achieve presumed co-management benefits. However, parties enter these agreements strategically. We should study, not assume, participant goals in collaborative processes and co-management institutions and pay special attention to the opportunities and constraints of federal laws and institutional culture for collaborative resource management with tribal and local communities.     

Comparative embryotoxicity of a pentabrominated diphenyl ether mixture to common terns (Sterna hirundo) and American kestrels (Falco sparverius)

Concentrations of polybrominated diphenyl ethers (PBDEs) in Forster’s tern (Sterna forsteri) eggs from San Francisco Bay have been reported to range up to 63 μg g⁻¹ lipid weight. This value exceeds the lowest-observed-adverse-effect level (1.8 μg g⁻¹ egg wet weight; ∼32 μg⁻¹ lipid weight) reported in an embryotoxicity study with American kestrels (Falco sparverius). As a surrogate for Forster’s terns, common tern (Sterna hirundo) eggs were treated by air cell injection with corn oil vehicle (control) or a commercial penta-BDE formulation (DE-71) at nominal concentrations of 0.2, 2, and 20 μg g⁻¹ egg. As a positive control, kestrel eggs received vehicle or 20 μg DE-71 g⁻¹ egg. In terns, there were no effects of DE-71 on embryonic survival, and pipping or hatching success; however, treated eggs hatched later (0.44 d) than controls. Organ weights, organ-to-body weight ratios, and bone lengths did not differ, and histopathological observations were unremarkable. Several measures of hepatic oxidative stress in hatchling terns were not affected by DE-71, although there was some evidence of oxidative DNA damage (8-hydroxy-deoxyguanosine; 8-OH-dG). Although DE-71 did not impair pipping and hatching of kestrels, it did result in a delay in hatch, shorter humerus length, and reduced total thyroid weight. Concentrations of oxidized glutathione, reduced glutathione, thiobarbituric acid reactive substances, and 8-OH-dG in liver were greater in DE-71-treated kestrels compared to controls. Our findings suggest common tern embryos, and perhaps other tern species, are less sensitive to PBDEs than kestrel embryos.     

Forest owners’ perceptions of ecotourism: Integrating community values and forest conservation

The use of forest land for ecotourism has been well accepted due to its ability to provide income to local people and to conserve the forest. Preparing the forest with infrastructure to attract and educate visitors has been reported of importance. This study applied Q methodology in a small rural community of the State of Puebla, Mexico, to reveal forest owners’ perceptions to build infrastructure in their forest as part of their ecotourism project. It also discloses forest owners’ underlying motives to use their forest for ecotourism. Ecotourism is perceived as a complementary activity to farming that would allow women to be involved in community development. Low impact infrastructure is desired due to forest owners’ perception to preserve the forest for the overall community well-being.     

Authority Pooling and Regional Organic Agriculture Standard-Setting: Evidence from East Africa

A key characteristic of global organic agriculture governance through standards is the coexistence of regulatory fragmentation and regional integration. To reduce barriers to organic trade, especially for market participants from developing countries, international and transnational entrepreneurs increasingly promote the setting of organic agriculture standards (OAS) in different world regions, for example, in East Africa, the Pacific, or Asia. Although scholars from different disciplines have done a lot of research on the role of standards in global governance, we still know little about why and how regional standard-setting processes evolve. Applying findings from regime analysis, entrepreneurship, and political authority, the article introduces the concept of authority pooling. It argues that legal, moral, and technical authority sources interact in a blurred functional division of labour between the public and the private sector in standard-setting. The article presents results from a within-case study of the development of the East African Organic Products Standard using the process-tracing method. It detects the underlying causal mechanism by which international and transnational entrepreneurs pooled different authority sources and, thus, significantly influenced political actors in East Africa to set the first regional OAS in the developing world.