Post-graduate Research Students Projects
Airborne Particulate Matter In The Cardiff Area For 1954-1991 In Relation To Environmental Factors And Health.
Research Student Dr. C.S. Potter
Supervisors: Prof J. Emberlin, The National Pollen and Aerobiology Research Unit, University of Worcester, Worcester, England and Dr J Mullings, Llandough Hospital Cardiff.
The PhD examination was held in June 2004. the degree was awarded subject to minor amendments
There is no routine data available on the size, composition and concentration of airborne particles. Recent evidence has implicated these characteristics, especially the ultrafine particles (Quality of Urban Air Review Group, 1996) in having the paramount effect on health. The Black Smoke method was the traditional method of measuring airborne particulate matter until the recent introduction of automatic gravimetric TEOM monitors. Neither method provides an effective indication of the mass of particles per unit volume of air.
The project is investigating the size and concentrations of airborne particulate matter from a set of microscope slides of volumetric daily air samples taken by Hirst-type air samplers. The samples are from a continuous record collected in Cardiff City center. These slides are unique worldwide as they date from 1956 to 1996, and contain data which precedes any other measurements of PM10 (Particulate Matter less than 10µm in diameter). The slides have been analysed by an image analysis system, which is measuring the size and concentration of airborne particles. A requirement of the project has been to develop the Image Analysis system. The system has never been previously used to examine air samples taken by a Hirst-type trap. The reason for using an IA is that it can determine the characteristics, concentration and numbers of PM10 relatively quickly. Environmental data including wind speeds, rain fall and temperature measurements have been investigated to examine the influence on the temporal variation of the abundance and characteristics of airborne particulate matter. Confounding factors that have an impact on cardiovascular and respiratory illness have been examined including data on aeroallergens, nitrogen oxide, sulphur dioxide, and carbon monoxide. The project includes the analysis of the results in relation to the incidence of mortality and hospital admissions as a consequence of cardiovascular and respiratory illness.
The
development of medium and long range forecast models for allergenic pollen
in the United Kingdom.
Research Student : Dr. Matthew Smith Project joint funded by University of Worcester and Surveillance Data Inc. (SDI), USA
Supervisors: Prof Jean Emberlin and Dr. Andrew Kress ( SDI) Started: October 2000 Finished: March 2004. PhD awarded to Dr. Mathew Smith
Evidence indicates that pollinosis (allergy to pollen) may affect between 10-25% of the UK population. The aim of this research is to develop medium range (7 to 10 days) and long range (1 month ahead) forecast models to predict the course of the grass and birch pollen seasons, the most allergenic taxa.The results of this study may be useful for a number of people and organisations:
- Accurate forecasts aid hayfever sufferers and asthmatics who are allergic to pollen.
- The forecasts are useful to health care services in planning treatments and clinical trials.
- Commercial applications include; the marketing of medication and related products, advertising and stock flow.
- The research will have academic and economic applications in fields as aerobiology, palaeo-palynology, ecology, biogeography and agriculture.
Forecast
models will be constructed using statistical methods such as correlation
analysis, linear regression, stepwise multiple regression and time series
analysis. The variables to be incorporated in the models will include
the features of past pollen seasons, phenology (plant development in relation
to the seasons) and meteorological data such as air temperature and precipitation.
The dispersal of pollen will also be investigated within the catchment
areas of monitoring sites. This will help to increase the accuracy of
forecast models. At a regional scale, phenological observations may also
be used to monitor the effects of changes to the environment, such as
urbanisation and climate change, on the flora of anemophilous plants.
This may be particularly relevant when considering recent predictions
by the IPCC (Intergovernmental Panel on Climate Change) of global temperatures
rising between 1.4 and 5.8 degrees Celsius over the next 100 years.
The interaction of mist and fogs with pollen and pollutants in the context of their effects on asthma and COPD
Research Student: Dr Gabriele Price
Supervisors: Prof J. Emberlin, The National Pollen and Aerobiology Research Unit, University of Worcester, Worcester, England and Prof R. Lewis, Consultant in General and Respiratory medicine Worcestershire Royal Hospital
Project joint funded by University of Worcester and Worcestershire Royal Hospital, Worcestershire
Acute Hospitals NHS Trust
Completed: March 2007
Chronic obstructive pulmonary disease (COPD) and asthma are frequent causes of morbidity and mortality in developed countries. Whilst both conditions exhibit many overlapping features related to smoking, they essentially differ in their aetiologies, pathologies, natural histories and response to treatment. These differences could result in a different reaction to environmental stimuli in asthma and COPD sufferers. Cigarette smoking is undoubtedly the most important risk factor in the development of chronic respiratory disease in adults. However, the smoking rates are greater in some Mediterranean countries where COPD is less common. For example, Greece, with 44.9% of population over 15 smoking daily (in contrast to 34.9% in the UK), has one of the highest smoking rates in Europe. Nevertheless, the age-adjusted death rates for COPD observed in Greece are one of the lowest world-wide. This indicates that other co-factors also play an important role in the development of COPD. Evidence suggests that a possible co-factor is the influence of mists and fogs and consequent higher humidity levels in our temperate climate. The research addresses a major aspect of this problem by investigating the interaction between airborne water droplets, plant allergens and pollutants in the context of their effect on asthma and particularly COPD.
The research began with analysis of the past hospital admission data for asthma and COPD for Worcester and Dudley. The data was standardised for population density, deprivation and age in asthma. Correlation and regression analysis was carried out to investigate whether a relationship between hospital admission and air pollutant levels, as well as meteorological variables, occurs. Areas of differing prevalence of COPD in Worcester and Dudley formed the basis of an environmental sampling scheme for mist and fog that was sampled using the Standard Fog Collector. The samples were analysed on allergen and pollutant content. A randomly selected group of COPD patients were asked to complete daily symptoms questionnaires in parallel with personal observations of some of the main local climatic conditions (such as occurrence of mist, fog, or rainfall). The results of this questionnaire were used to develop a site-map for Worcester and Dudley to show the variation of COPD control levels. The results of this study will contribute to a better understanding of the influence of the environment on the control of asthma and especially COPD. This could lead to achieving higher standards of treatment in pharmaceutical and prophylactic terms.
The Investigation of the aerodynamic properties of pollen grains with particular reference to the development of sampling methods.
Research Student: Dr Diego Fernandez Sevilla
Supervisors: Prof J. Emberlin, The National Pollen and Aerobiology Research Unit, University of Worcester, Worcester, England and Dr Eckart Schultz, German Weather Service
Cofunded by the German Weather Service, Freiburg and University of Worcester.
Completed in March 2007 and PhD awarded.
Aerobiology
is the study of the passive transport of biological particles in the air.
It has applications in many areas including allergy (e.g. hayfever and
asthma), crop pollination, forestry, horticulture, forensics and biodeterioration.
A fundamental aspect of the science is the efficient sampling of pollen
grains from the air. This involves understanding the aerodynamic properties
of pollen grains, as airborne particles and as non-spherical bodies.
A central theme is the requirement for detailed information about the
residence time of atmospheric particles, which is highly dependent on
their deposition velocity. This basic parameter is an essential component
for modeling dispersal and atmospheric transport and is of special interest
for pollen forecasting and the escape of transgenic pollen from genetically
modified crops. Off-site movement of pollen poses a potential risk of
genetic contamination in managed non-GM organic and conventional production
fields.
There has also been concern that GM pollen that incorporates genes for an insect toxin that may pose a potential hazard to non-target insect species. There is a need for a quantitative model of pollen movement in the atmosphere to help evaluate these potential risks.
It has been observed that pollen grains have the capacity to change characteristics that affect settling velocities (e.g. shape, size, weight and density), which are connected with changing parameters in the environment such as relative humidity, time after pollen shedding. Reliable data on real-world pollen deposition velocities are needed as little attention has been given to this topic:
- To determine the aerodynamic properties of pollen grains in order to characterize the features which influence pollen settling velocity for selected species (primarily those important for allergy and agriculture).
- Validate the Sigma-2 sedimentation sampler and filtration technique of measuring atmospheric pollen concentrations.
- To develop an efficient method for sampling pollen grains in the atmosphere.
- To provide detailed data to enable more reliable modeling of pollen dispersal.
Methodology, phasing and timescales (including MPhil/PhD transfer point)
The project
will investigate pollen settling velocities in wind tunnel experiments
and calculate them from collocated deposition and concentration measurement
in a range of conditions.
For this purpose pollen grains will be sampled in parallel and counted
on different sampling media such as impaction surfaces (Burkard pollen
trap), deposition surface (Sigma-2 sedimentation sampler) and filtration
(Low Volume sampler).
Pilot studies will be carried out in order to validate and estimate the
efficiency of some proposed instruments for pollen sampling such as Sigma2
and filtration. Also pollen grains will be sampled in parallel and counted
on different sampling media, similar to the wind tunnel experiments, through
the pollen season in outdoor conditions. Sampling media instruments will
be situated close to a meteorological station in Worcester. The initial
work will involve traditional counting with optical microscopy but it
is envisaged that an image processing system for automatic pollen recognition
and counting will be used later. Current research work at the German Weather
Service laboratory in Freiburg, Germany will provide the tools for this
subject.
Forecast models for the main features of the pollen season and daily average counts for allergenic taxa in central Albania
Research Student: Elona Hoxha
Supervisors: Prof J. Emberlin, The National Pollen and Aerobiology Research Unit, University of Worcester, Worcester, England and Dr. G Frenuelli, Head of the Department of Plant Biology, University of Perugia, Italy.
Funded by the British Council, Chevening Scholarship
Completed: July 2007, PhD awarded with minor amendments
The study will be based on the pollen counts and the weather data from central Albania. Very little work has been done on aerobiology in Albania, and this work represents a major advance. The monitoring and analysis of the pollen seasons will provide a new database for aerobiology. The forecast models will be useful for clinicians in planning treatment and for the public in planning their activities as well as for the health care industry in providing better management of allergic diseases.
The daily average pollen counts of airborne pollen have been monitored in Tirana since 1995. The daily weather data for temperature and rainfall for the same period has been obtained already from the Metrological Institute in Tirana.
The research will be based firstly on determination of the main characteristics of the pollen seasons (timing, severity, length of the season) and the daily variation of Poaceae (grass), Olea (Olive), Urticaeae (Nettle). Also the work during this period will concentrate on the relationships between the main features of the pollen seasons and the weather parameters.
Environmental determinants of allergens in different flooring materials and the influence of vacuum cleaning on this and airborne allergen concentrations
Research Student: Hannah Cunniffe
Supervisors: Prof . Jean Emberlin
Completed July 2006 and PhD awarded
Aimed to determine the colonisation rates of house dust mites in different types of flooring materials and how this is influenced by vacuum cleaning; to assess the common fungal taxa present within carpets and how differing environmental determinants influence this; to develop more efficient cleaning regimes for the removal of house dust mite allergens from smooth and carpeted floors; and to assess the influence of vacuum cleaning on the airborne concentrations of Der p1 and fungal spores from rooms with smooth and carpeted floors.
The role of allergy to fungi in the association between asthma prevalence and deprivation: Case controlled research.
Research Student: Melanie Jones
Project joint funded by University of Worcester and Worcester Acute Hospitals NHS Trust
Supervisors: Prof . Jean Emberlin and Prof Richard Lewis (Worcester Royal Hospital) Start date: May 1999
Introduction
It is estimated that 6% of the British population suffer from asthma and that both prevalence and hospital admissions are on the increase. Several studies have indicated that damp homes have a detrimental effect on health, particularly respiratory disorders such as asthma. House surveys throughout England and Scotland have suggested that between a third and a quarter of homes are affected by damp and mould to some degree. It has previously been shown in the West Midlands that there is a clear association between hospital admission rates and deprivation. However the study was based on area deprivation and not individual. This study will to help answer the question: Do the higher hospital admission rates in more deprived areas indicate that there is a higher admission rate for individual poorer patients? The objectives of the study are to investigate:
- The prevalence of allergy to indoor fungi within two health districts.
- The Indoor environment, with particular reference to indoor fungi, dampness.
- To see if there is an association between the prevalence of allergy to indoor fungi and socio-economic deprivation.
- To assess the socio-economic deprivation of hospital admitted asthmatics and non-hospital admitted asthmatics.
Methodology
The overall aim is to investigate the relationship between asthma hospital admissions and the prevalence of allergy to indoor fungi in the context of social deprivation. This will be achieved by conducting a case controlled study, in which asthmatics admitted to hospital from a full spectrum of deprived and affluent communities will be compared to controls selected from the same and different areas. The study will assess the occurrence of dampness in homes, the spectrum of indoor fungi allergens, the prevalence of allergy to fungi, and social deprivation. To achieve this data will be collected in 4 ways. 1. A detailed questionnaire designed to obtain information on asthma severity, history, and education, deprivation, and the home environment. 2. A home survey conducted where dust samples will be collected using a DYSON vacuum cleaner with an ALK attachment. The Dust samples will be analysed for fungal allergens using Enzyme Linked Immunosorbant Assay (ELISA). 3. During the home survey damp measurements will be made using a protiometer. 4. The prevalence of allergy to fungi will be established by conducting a skin allergy test.
Sponsors: We would like to thank DYSON and Allergy Therapeutics for their support and sponsorship in this project.