Lead pollution in the New Zealand environment : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Chemistry at Massey University

Section I: The optimum conditions for the determination of lead by atomic absorption Spectrophotometry were investigated. Using the analysis line 2170A°, vegetation and soils could be analysed with satisfactory reproducibility. Lead concentrations in solution were determined in some cases at levels ten-fold higher than normal environmental (background) levels. The productivity of various analytical techniques used, in particular sample preparation, were shown to affect the analysis of lead in vegetation (leaves, barks, ring-cores) and soil samples. Section II: The effects of lead from motor-vehicle exhausts on trees growing along a busy thoroughfare in Palmerston North, New Zealand, were investigated. Analysis of tree samples (leaves, bark, trunk cores) and of soils, showed that the distribution of emitted lead was influenced by the direction of the prevailing wind. Lead levels were higher on the sides of trees facing the traffic. Measurements of lead concentrations in leaves, bark and soils, showed considerable accumulation in the vegetation at distances of about 5m from the main traffic movement. An investigation was carried out to determine the seasonal variation in lead content of tree leaves and dust samples along the thoroughfare and in the Palmerston North Square. It was found that only a gradual seasonal increase in the lead content occurred in leaves from the initial time of development to exfoliation. High lead levels in young leaves indicated a rapid accumulation of lead. A comparison of the lead content of Whatman filter papers and of leaves exposed to motor-vehicle exhausts, showed a significant difference associated with the type of surface retention mechanism. Dust samples from the Palmerston North Square showed no direct pattern of seasonal variation. Section III: The lead content of soil and vegetation along part of a State Highway passing through an uninhabited area of New Zealand was investigated. The region studied was 20 km from the nearest town and was traversed by a single highway carrying an average of 1200 motor vehicles per day (1973). The topography was fairly flat, about 1000 m above sea level, and the light volcanic soil supported vegetation less than 1 m in height. Analysis of soil and vegetation samples showed that elevated levels of lead occurred within 100 m of the edge of the highway. Close to the highway the decrease of lead levels in vegetation was approximately exponential, with the excess over background levels being halved about every 10-20 m. Accumulation of lead in soils, even within 10m of the highway, was significant only down to a depth of 5 cm. It is estimated that the total amount of lead in excess of background soil values, contained within 250 m of the roadway and within 6 cm of the surface, represented a significant proportion of the total lead emitted by all vehicles that have traversed the highway since the introduction of lead tetra-alkyls into motor fuel. Section IV: Lead concentrations in vegetation and soils were measured in the vicinity of the Tui Mine, Te Aroha, New Zealand. Lead levels in leaves of Beilschmiedia tawa reflected dispersion of wind-borne material around an ore treatment plant. Vegetation growing over an ore body show very high lead concentrations accumulated by the root systems. This mode of uptake could be easily differentiated from airborne deposition by the much lower proportion of the metal burden, which was removable by washing. Analysis of trunk core sections showed again a dissimilar pattern between air-borne deposition and accumulation of lead via the root system. With air-borne accumulation, trunk-cores showed a significant increase of levels towards the outside of the trunk. When accumulated via the root system, lead concentrations were appreciably uniform through the entire trunk. Section V: Sweet-corn plants (husks, leaves, stalks, kernels, cobs) and soils in the vicinity of a Hastings-Napier highway were analysed for lead fallout from motor vehicle exhausts. The distribution of lead was influenced by the direction of the prevailing wind and by traffic volume. Lead levels in inedible parts of the plants (leaves, husks, stalks and cobs) were ten-fold higher in plants near the roadway than in plants taken from background areas. Edible portions (kernels) were relatively low in lead. Extraction studies showed that a considerable portion of the total lead burden was present as a superficial deposit removable by washing with water. The evidence favoured air-borne lead rather than soil-borne lead as the main contributor to elevated levels of this element in plant tissues

Law and the Demand for Property-Casualty Insurance Consumption

This paper examines the importance of legal rights and enforcement in influencing property-casualty insurance consumption. We extend the existing literature by examining the role of legal factors in determining insurance density across countries. Also, measures of risk aversion, loss probability and price, which overcome limitations of proxies used in the existing literature on insurance demand are analysed. Using a panel data set we apply a Generalized Methods of Moments dynamic system estimator, which relaxes the assumption of strict exogeneity of the regressors and produces unbiased and efficient estimates. The results show a strong positive relationship between the protection of property rights and insurance consumption, which is robust to various model specifications and estimation techniques. Moreover, the results show the purchase of property-casualty insurance is significantly and positively related to loss probability and income, as well as providing weaker evidence of a negative relationship with price.

Applications of interannual-to-decadal climate prediction: an exploratory discussion on rainfall in the Sahel Region of Africa

This perspective explores how climate services may potentially incorporate information emerging from the new science of interannual-to-decadal (I2D) climate prediction. The geographic focus is the Sahel region of West Africa, which has demonstrated prediction advances for rainfall on the I2D timescale, and vulnerability to climate hazards. The perspective draws on reviews of predictability and applications in the region and a national workshop in Sudan to explore applications. Decadal prediction is an emerging capability, to date being undertaken primarily as a learning process. However, for the multi-year forecast information, we identify a number of new dimensions that challenge product design and user uptake. Current experiments often present forecasts as the average conditions for a target first year, and then subsequent set of years raising a question of what a forecast of mean average conditions for years 2-5 represents in terms of climate to expect, and how annual updates to multi-year forecasts may be produced and communicated. Stakeholder consultations highlighted some of the concerns noted for existing seasonal forecasts, but now translated into terms for multi-year information, such as confidence in information, need for research on temporal downscaling (which may now include information on the risks of climate anomalies in the individual years that make up the forecast period), capacity development, and that communities would need to be convinced about effectiveness, alongside careful communication, especially in the context of multi-year planning. This perspective captures one of the first learning case studies on how I2D prediction may be explored in a given region, a first step towards climate services development that integrate I2D information

Sequence effects in the categorization of tones varying in frequency

In contrast to exemplar and decision-bound categorization models, the memory and contrast models described here do not assume that long-term representations of stimulus magnitudes are available. Instead, stimuli are assumed to be categorized using only their differences from a few recent stimuli. To test this alternative, the authors examined sequential effects in a binary categorization of 10 tones varying in frequency. Stimuli up to 2 trials back in the sequence had a significant effect on the response to the current stimulus. The effects of previous stimuli interacted with one another. A memory and contrast model, according to which only ordinal information about the differences between the current stimulus and recent preceding stimuli is used, best accounted for these dat

The Political Economy of Aid for Power Sector Reform

Recent literature on the effectiveness of donor programmes points to the importance of understanding the political context within which reforms are taking place. The characteristics of the power sector make reform intensely political in almost all countries and donor projects have sometimes failed because of an inability to navigate the local politics of reform. This article reviews what is known about how donors have taken politics into account in designing and implementing power sector reform programmes in sub-Saharan Africa. It illustrates the challenges which donors have faced with reference to a case study of donor attempts to support power sector reform in Tanzania. The article draws on documentary evidence from major donors as well as a set of qualitative interviews with experienced project supervisors to provide a set of lessons for donors about how to incorporate political context into the design and implementation of power sector projects

Contact after adoption::a follow-up in late adolescence

We would like to acknowledge the help of the many people who made this study possible, some of whom cannot be named individually for reasons of confidentiality. The research was funded by The Nuffield Foundation and was carried out in 2012 and 2013. Firstly we would like to thank all the adopted young people, adoptive parents and birth relatives who took part in the study. Their willingness to share their personal experiences and to take time to fill in questionnaires was vital to the success of the project. We would also like to thank the social workers and administrative staff from the participating adoption agencies who assisted us in tracing participants whose contact details were out of date. We are grateful to the help of After Adoption who assisted us in recruiting a group of adopted young people to advise us on the early stages of the study, and of course to the young people themselves who made many valuable suggestions which informed our data collection strategy

Atrial fibrillation and survival in colorectal cancer

BACKGROUND: Survival in colorectal cancer may correlate with the degree of systemic inflammatory response to the tumour. Atrial fibrillation may be regarded as an inflammatory complication. We aimed to determine if atrial fibrillation is a prognostic factor in colorectal cancer. PATIENTS AND METHODS: A prospective colorectal cancer patient database was cross-referenced with the hospital clinical-coding database to identify patients who had underwent colorectal cancer surgery and were in atrial fibrillation pre- or postoperatively. RESULTS: A total of 175 patients underwent surgery for colorectal cancer over a two-year period. Of these, 13 patients had atrial fibrillation pre- or postoperatively. Atrial fibrillation correlated with worse two-year survival (p = 0.04; log-rank test). However, in a Cox regression analysis, atrial fibrillation was not significantly associated with survival. CONCLUSION: The presence or development of atrial fibrillation in patients undergoing surgery for colorectal cancer is associated with worse overall survival, however it was not found to be an independent factor in multivariate analysis