A Critical Commentary on A Morbidity Study

The approach, methods, data, and results set out by Crocker et al.¹ in their study of the effect and valuation of air pollution on human morbidity are examined in detail. It is found that there are severe deficiencies in both method and data which make the results of extremely doubtful value for the purposes of policy formulation.     

Comparison of the cytotoxic responses of Escherichia coli (E. coli) AMC 198 to different fullerene suspensions (nC60)

Fullerenes are set to be produced on an industrial scale in anticipation of their wide applications. This calls for research on their environmental and health impacts. This study investigates and compares the cell toxicity of different aqueous fullerene aggregates. Popular C₆₀ dispersal methods were used to prepare four types of nC₆₀ aggregates. These aggregates were tested against the indicator species Escherichia coli (E. coli) AMC 198. With aggregates of around 150 nm in diameter, the THF/nC₆₀ suspension was very toxic and gave rise to a half maximal effective concentration (EC₅₀) of 0.54 mg L⁻¹ in E. coli. By contrast, the Tol/nC₆₀ suspension exhibited a cytoprotective role while the Aqu-N₂/nC₆₀ and Aqu-O₂/nC₆₀ suspensions enhanced the metabolism of E. coli. Although some toxicants, such as THF and THF-peroxide, were introduced into the THF/nC₆₀ suspension during the dispersion, the toxicity of nC₆₀ itself cannot be neglected.     

Developments in application technology

Pesticides are applied in diverse situations, but in each, careful consideration has to be given to applying the optimum dosage accurately with minimal exposure of the active substance to the operator. Emphasis is given to ways in which application equipment, suitable for both small-scale and large farms has been adapted to meet health and safety requirements. New developments in nozzle design provide users with greater flexibility in optimising pesticide delivery, while minimising spray volumes. Changes in equipment design that influence dose transfer are discussed.     

Interpreting nitrogen pollution thresholds for sensitive habitats: the importance of concentration versus dose

Nitrate and ammonium concentration in wet deposition detrimentally impacted a sensitive pollution indicator species irrespective of the nitrogen dose.     

Dispersion modeling to compare alternative technologies for odor remediation at swine facilities

The effectiveness of 18 alternative technologies for reducing odor dispersion at and beyond the boundary of swine facilities was assessed in conjunction with an initiative sponsored through agreements between the Attorney General of North Carolina and Smithfield Foods, Premium Standard Farms, and Frontline Farmers. The trajectory and spatial distribution of odor emitted at each facility were modeled at 200 and 400 m downwind from each site under two meteorological conditions (daytime and nighttime) using a Eulerian-Lagrangian model. To predict the dispersion of odor downwind, the geographical area containing the odorant sources at each facility was partitioned into 10-m2 grids on the basis of satellite photographs and architectural drawings. Relative odorant concentrations were assigned to each grid point on the basis of intensity measurements made by the trained odor panel at each facility using a 9-point rating scale. The results of the modeling indicated that odor did not extend significantly beyond 400 m downwind of any of the test sites during the daytime when the layer of air above the earth's surface is usually turbulent. However, modeling indicated that odor from all full-scale farms extended beyond 400 m onto neighboring property in the evenings when deep surface cooling through long-wave radiation to space produces a stable (nocturnal) boundary layer. The results also indicated that swine housing, independent of waste management type, plays a significant role in odor downwind, as do odor sources of moderate to moderately high intensity that emanate from a large surface area such as a lagoon. Human odor assessments were utilized for modeling rather than instrument measurements of volatile organic compounds (VOCs), hydrogen sulfide, ammonia, or particulates less than 10 microm in diameter (PM10) because these physical measurements obtained simultaneously with human panel ratings were not found to accurately predict human odor intensity in the field.     

Performance assessments for the geological storage of carbon dioxide: Learning from the radioactive waste disposal experience

The geological storage of carbon dioxide is currently being considered as a possible technology for reducing emissions to atmosphere. Although there are several operational sites where carbon dioxide is stored in this way, methods for assessing the long-term performance and safety of geological storage are at an early stage of development. In this paper the similarities and differences between this field and the geological disposal of radioactive wastes are considered. Priorities are suggested for the development of performance assessment methods for carbon dioxide storage based on areas where experience from radioactive waste disposal can be usefully applied. These include, inter alia, dealing with the various types of uncertainty, using systematic methodologies to ensure an auditable and transparent assessment process, developing whole system models and gaining confidence to model the long-term system evolution by considering information from natural systems. An important area of data shortage remains the potential impacts on humans and ecosystems.     

FORUM: A Context for Participation in Sustainable Development

sustainability, but the most meaningful definition is set within an evolutionary framework. Mechanistic and evolutionary frameworks for sustainable development are discussed. Evolution and adaptation are characteristics of complex adaptive systems, and a new understanding of sustainable development can be gleaned by using the complex adaptive systems framework. This approach to sustainable development issues implicitly requires proactive involvement by the public. This paper supports that bottom-up participation needs to be nurtured. Appropriate processes to enable participation need to be designed and implemented.