The Use of Aircraft in Air Pollution Research

An instrumented single engine aircraft is being used to characterize plumes from large emission sources. By cross sectioning these plumes at a number of points we hope to describe the character and concentration of pollution as it ages and travels downwind under known meteorological conditions. This paper reports experimental work thus far completed on aerosol measurement. Flights have been made through plumes from a large coal-fired power station, forest fires, and a gravel plant. Particle counts in various size classifications were made with a Bausch and Lomb 40–1 Dust Counter which was carried in the aircraft. Selected meteorological parameters were recorded. Results show the aerosol concentrations in various size classifications that are found at successive distances downwind from these sources for distances up to 32 miles. Background aerosol concentrations are also reported, and variations in these can be noted with respect to time, location and altitude.     

Guidance for the Performance Evaluation of Three-Dimensional Air Quality Modeling Systems for Particulate Matter and Visibility

ABSTRACT

Guidance for the performance evaluation of three-dimensional air quality modeling systems for particulate matter and visibility is presented. Four levels are considered: operational, diagnostic, mechanistic, and probabilistic evaluations. First, a comprehensive model evaluation should be conducted in at least two distinct geographical locations and for several meteorological episodes. Next, streamlined evaluations can be conducted for other similar applications if the comprehensive evaluation is deemed satisfactory. In all cases, the operational evaluation alone is insufficient, and some diagnostic evaluation must always be carried out. Recommendations are provided for designing field measurement programs that can provide the data needed for such model performance evaluations.     

Screening for antioxidant and detoxification responses in Perna canaliculus Gmelin exposed to an antifouling bioactive intended for use in aquaculture

Polygodial is a drimane sesquiterpene dialdehyde derived from certain terrestrial plant species that potently inhibits ascidian metamorphosis, and thus has potential for controlling fouling ascidians in bivalve aquaculture. The current study examined the effects of polygodial on a range of biochemical biomarkers of oxidative stress and detoxification effort in the gills of adult Perna canaliculus Gmelin. Despite high statistical power and the success of positive controls, the antioxidant enzymes glutathione reductase (GR), glutathione peroxidase (GPOX), catalase (CAT), and superoxide dismutase (SOD); thiol status, as measured by total glutathione (GSH-t), glutathione disulphide (GSSG), and GSH-t/GSSG ratio; end products of oxidative damage, lipid hydroperoxides (LHPO) and protein carbonyls; and detoxification pathways, represented by GSH-t and glutathione S-transferase (GST), were unaffected in the gills of adult P. canaliculus exposed to polygodial at 0.1 or 1 × the 99% effective dose in fouling ascidians (IC₉₉). Similarly, GR levels, thiol status, and detoxification activities were unaffected in mussels exposed to polygodial at 10 × the IC₉₉, although GPOX, CAT, and SOD activities increased. However, the increases were small relative to positive controls, no corresponding oxidative damage was detected, and this concentration greatly exceeds effective doses required to inhibit fouling ascidians in aquaculture. These findings compliment a previous study that established the insensitivity to polygodial of P. canaliculus growth, condition, and mitochondrial functioning, providing additional support for the suitability of polygodial for use as an antifouling agent in bivalve aquaculture.     

Persistent organochlorine pollutants and menstrual cycle characteristics

An evolving body of evidence suggests an adverse relation between persistent organochlorine pollutants (POPs) and menstruation, though prospective longitudinal measurement of menses is limited and served as the impetus for study. We prospectively assessed the relation between a mixture of persistent organochlorine compounds and menstrual cycle length and duration of bleeding in a cohort of women attempting to become pregnant. Eighty-three (83%) women contributing 447 cycles for analysis provided a blood specimen for the quantification of 76 polychlorinated biphenyls and seven organochlorine pesticides, and completed daily diaries on menstruation until a human chorionic gonadotropin confirmed pregnancy or 12 menstrual cycles without conception. Gas chromatography with electron capture detection was used to quantify concentrations (ng g⁻¹ serum); enzymatic methods were used to quantify serum lipids (mg dL⁻¹). A linear regression model with a mixture distribution was used to identify chemicals grouped by purported biologic activity that significantly affected menstrual cycle length and duration of bleeding adjusting for age at menarche and enrollment, body mass index, and cigarette smoking.A significant 3-d increase in cycle length was observed for women in the highest tertile of estrogenic PCB congeners relative to the lowest tertile (β = 3.20; 95% CI 0.36, 6.04). A significant reduction in bleeding (<1 d) was observed among women in the highest versus lowest tertile of aromatic fungicide exposure (γ = −0.15; 95% CI −0.29, −0.00). Select POPs were associated with changes in menstruation underscoring the importance of assessing chemical mixtures for female fecundity.     

Modelling of the fate of selected endocrine disruptors in a municipal wastewater treatment plant in South East Queensland, Australia

The aim of this study was to develop a fugacity-based analysis of the fate of selected industrial compounds (alkylphenols and phthalates) with endocrine disrupting properties in a conventional activated sludge wastewater treatment plant (WWTP A) in South East Queensland, Australia. Using mass balance principles, a fugacity model was developed for correlating and predicting the steady-state-phase concentrations, the process stream fluxes, and the fate of four phthalates and four alkylphenols in WWTP A. Input data are the compound's physicochemical properties, measured concentrations and the plant's operating design and parameters. The relative amounts of chemicals that are likely to be volatilized, sorbed to sludge, biotransformed, and discharge in the effluent water was determined. Since it was difficult to predict biotransformation, measured concentrations were used to calibrate the model in terms of biotransformation rate constant. Results obtained by applying the model for the eight compounds showed <40% differences between most of the estimated and measured data from WWTP A. All eight compounds that were modelled in this study had high removal efficacy from WWTP A. Apart from benzyl butyl phthalate and bisphenol A, the majority is removed via biotransformation followed by a lesser proportion removed with the primary sludge. Fugacity analysis provides useful insight into compound fate in a WWTP and with further calibration and validation the model should be useful for correlative and predictive purposes.     

Learning about climate-related risks: decisions of Northern Thailand fish farmers in a role-playing simulation game

River-based cage aquaculture in Northern Thailand involves dealing with a number of climate- and weather-related risks. The purpose of this study was to improve understanding of how farmers make investment decisions in their fish farms when faced with risks from floods that are imperfectly known, and which may be changing. A role-playing simulation game was created to capture some of the key features of the decision-making context and explored with farmers in the field. In-depth interviews were conducted post-game to reflect on strategies used in the game as compared to in practice. As hypothesized, more frequent or larger impact floods reduced cumulative profits. Farmers reduced their stocking densities when playing in games with high likelihood of floods, but did not do so in games with large impacts when a flood occurred. Contrary to initial expectations, farmers were less likely to learn from experience—choose the optimal density and thus improve score within a game—when floods were common or had large impacts. Farmers learnt most when risks were decreasing and least when they were increasing. Providing information about likelihoods prior to a game had no impact on performance or decisions. The methods and findings of this study underline the importance of understanding decision-making behaviour around risks for climate risk management. The novel combination of experimental, role-playing, and qualitative methods revealed limitations in common assumptions about the ease of learning about risks from previous experiences. The findings also suggest that decision-support systems for aquaculture need to take into account how recent experiences, understanding of information, and other factors influence risk perceptions and decisions.     

Local knowledge and adaptation to climate change in natural resource-based societies of the Asia-Pacific

This paper reviewed 42 studies of how local knowledge contributes to adaptation to climate and climate change in the Asia-Pacific Region. Most studies focused on traditional ecological or indigenous knowledge. Three simple questions were addressed: (1) How are changes in climate recognized? (2) What is known about how to adapt to changes in climate? (3) How do people learn about how to adapt? Awareness of change is an important element of local knowledge. Changes in climate are recognized at multiple time scales from observations that warn of imminent extreme weather through expectations for the next season to identification of multi-year historical trends. Observations are made of climate, its impact on physical resources, and bio-indicators. Local knowledge about how to adapt can be divided into four major classes: land and water management, physical infrastructure, livelihood strategies, and social institutions. Adaptation actions vary with time scale of interest from dealing with risks of disaster from extreme weather events, through slow onset changes such as seasonal droughts, to dealing with long-term multi-year shifts in climate. Local knowledge systems differ in the capacities and ways in which they support learning. Many are dynamic and draw on information from other places, whereas others are more conservative and tightly institutionalized. Past experience of events and ways of learning may be insufficient for dealing with a novel climate. Once the strengths and limitations of local knowledge (like those of science) are grasped the opportunities for meaningful hybridization of scientific and local knowledge for adaptation expand.     

Prenatal identification of a 45,X/46,Xder(Y) mosaicism and confirmation by high resolution cytogenetics and fluorescence in situ hybridization

A 45,X/46,Xder(Y) mosaicism detected prenatally was shown to have a rare Y inversion- duplication or Y/Y translocation which can only be identified by a combination of high resolution cytogenetics and fluorescence in situ hybridization. The present data indicate the usefulness and importance of chromosome-specific probes in the identification and characterization of chromosome rearrangements.     

Prenatal detection of the congenital nephrotic syndrome (Finnish type) by trehalase assay in amniotic fluid

We report relatively high trehalase activity in the amniotic fluid of two fetuses affected with the congenital nephrotic syndrome of the Finnish type. The results suggest that prenatal detection of this condition can be done on this basis in conjunction with the α-fetoprotein and acetylcholinesterase tests in amniotic fluid.     

Climate change: linking adaptation and mitigation through agroforestry

Agriculture is the human enterprise that is most vulnerable to climate change. Tropical agriculture, particularly subsistence agriculture is particularly vulnerable, as smallholder farmers do not have adequate resources to adapt to climate change. While agroforestry may play a significant role in mitigating the atmospheric accumulation of greenhouse gases (GHG), it also has a role to play in helping smallholder farmers adapt to climate change. In this paper, we examine data on the mitigation potential of agroforestry in the humid and sub-humid tropics. We then present the scientific evidence that leads to the expectation that agroforestry also has an important role in climate change adaptation, particularly for small holder farmers. We conclude with priority research questions that need to be answered concerning the role of agroforestry in both mitigation and adaptation to climate change.