45 research outputs found
Biotechnology and industrial ecology: new challenges for a changing global environment
Human causes of global environmental change are invariably linked to inconsistencies in the relationship between industrial activities and ecological systems (industrial ecology). The choice of fuel materials used in the energy industry is directly responsible for increases in the atmospheric concentration of carbon dioxide, resulting in the current trend of global warming. The dependency of the agricultural industry on chemicals to sustain productivity in marginal landscapes has led to a global-scale contamination of the environment with toxic pesticides and with nutrient fertilizers that are changing the course of biogeochemical cycles. One of the strategies proposed to mitigate climate change is to lower dependency on fossil fuels by substituting renewable biomass. This strategy has several co-benefits for human health and the environment because it supports investments in agricultural biotechnology while reducing the adverse health impacts of combustion byproducts of fossil fuels. The strategy has limited likelihood for success if ârun-awayâ climate change modifies the ecosystem sufficiently to impact agricultural productivity. The development and global implementation of biotechnological approaches can contribute urgently needed solutions to problems associated with inefficiencies in the industrial ecology of agricultural and energy resources. The necessary biotechnological protocols are available, but scale-up techniques are limiting, particularly with respect to the cultivation and processing of alternative non-recalcitrant raw materials in stressful environments.
Key words: Biotechnology, industrial ecology, energy, agriculture, biofuels, climate change, desertification, genetic engineering.
African Journal of Biotechnology Vol. 2 (12), pp. 596-601, December 200
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Removal of lead from aqueous solutions by a poly(acrylic acid)/bentonite nanocomposite
The importance of the exposome and allostatic load in the planetary health paradigm
In 1980, Jonas Salk (1914-1995) encouraged professionals in anthropology and related disciplines to consider the interconnections between "planetary health," sociocultural changes associated with technological advances, and the biology of human health. The concept of planetary health emphasizes that human health is intricately connected to the health of natural systems within the Earth's biosphere; experts in physiological anthropology have illuminated some of the mechanisms by which experiences in natural environments (or the built environment) can promote or detract from health. For example, shinrin-yoku and related research (which first emerged from Japan in the 1990s) helped set in motion international studies that have since examined physiological responses to time spent in natural and/or urban environments. However, in order to advance such findings into planetary health discourse, it will be necessary to further understand how these biological responses (inflammation and the collective of allostatic load) are connected to psychological constructs such as nature relatedness, and pro-social/environmental attitudes and behaviors. The exposome refers to total environmental exposures-detrimental and beneficial-that can help predict biological responses of the organism to environment over time. Advances in "omics" techniques-metagenomics, proteomics, metabolomics-and systems biology are allowing researchers to gain unprecedented insight into the physiological ramifications of human behavior. Objective markers of stress physiology and microbiome research may help illuminate the personal, public, and planetary health consequences of "extinction of experience." At the same time, planetary health as an emerging multidisciplinary concept will be strengthened by input from the perspectives of physiological anthropology.Peer reviewe
Mercury Safety Reform in the 21st Century: Advancing the New Framework for Toxic Substances Control
The articles that follow are the latest in Environment Magazine's series looking back at seminal articles in the magazine's history that helped define a field of study or offered alternative explorations of new ideas. In this installment, we focus on the latest news in the hazards of the mercury toxin, juxtaposed with Environment's groundbreaking article on mercury published in 1969
Kinetics and thermodynamics of Pb sorption onto bentonite and poly(acrylic acid)/bentonite hybrid sorbent
In this work, bentonite (Bent) and poly(acrylic acid)âbentonite (PAAâBent) hybrid were applied for the removal of Lead (Pb) from aqueous solutions. Sorption experiments were conducted under batch condition at different times, Pb concentrations, and temperatures. Equilibrium studies showed that Pb sorption data on PAAâBent followed the Langmuir model. Both capacity and affinity of PAAâBent and Bent for Pb retention increased with rising temperature. Maximum capacity (qm) of PAAâBent for Pb sorption was 91.88 mg gâ1 at 15°C which increased to 96.13 mg gâ1 at 50°C. For the Bent sample, the qm values were 52.31 and 82.51 mg gâ1, respectively, at 15 and 50°C. The Langmuir Pb sorption affinity parameter (KL) was increased from 0.12 to 2.25 L mgâ1 for PAAâBent and from 0.009 to 1.19 L mgâ1 for Bent, as temperature rose from 15 to 50°C. Pseudo-first and pseudo-second-order kinetic models could best describe the time-dependent Pb sorption data by the PAAâBent which occurred at a fast rate approaching equilibrium within ~30â60 min. For the Bent sample, the Elovich model was the best fitted model to the Pb sorption data. Calculation of thermodynamic parameters including Gibbs free energy changes (ÎG° = â20.07 to â40.63 kJ molâ1), enthalpy change (ÎH° = 146.359 kJ molâ1), and entropy change (ÎS° = 578.42 J molâ1 Kâ1) showed that Pb sorption on the PAAâBent is more spontaneous, endothermic, and favored as compared to Pb sorption process on the Bent with ÎG°= â19.51 to â30.44 kJ molâ1, ÎH° = 70.02 kJ molâ1 and ÎS° = 310.94 J molâ1 Kâ1. In conclusion, the PAAâBent hybrid sorbent can be considered as a suitable candidate for the removal of Pb from aqueous solutions
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Circular economy and electronic waste
Electronic waste is the fastest growing category of hazardous solid waste in the world. Addressing the problem will require international collaboration, economic incentives that protect labour, and management approaches that minimize adverse impacts on the environment and human health
Cost effectiveness of regulation-compliant filtration to control sediment and metal pollution in urban runoff
The implementation of Total Maximum Daily Load (TMDL) to control urban runoff presents major structural and managerial challenges for cities. We developed a decision support system (DSS) for TMDL compliance at the city level to solve for a phased, least-cost strategy toward meeting four TMDLs using stormwater filtration. Based on a case-study city, we modeled wet weather flows and associated discharge of Total Suspended Sediment (TSS), cadmium, copper, and zinc to receiving waters by coupling U.S. EPA's Storm Water Management Model (SWMM v. 5.0) with the geographic dataset of the urban drainage network. We linked a mixed integer linear programming algorithm to the watershed model for deriving cost-effective selection and placement of curb inlet filters to meet mass- and concentration-based TMDL requirements. The least cost solution for meeting the city's TMDL waste load allocations for TSS (73.9% reduction), Cd (50.6% reduction), Cu (30.0% reduction), and Zn (55.7% reduction) would require 1071 filter inserts at a cost of 4.0 million and $4.8 million, respectively. Our results demonstrate the increases in cost-effectiveness of using an optimization-based DSS for urban watershed management. © 2007 American Chemical Society.link_to_subscribed_fulltex