United Nations Earth Summit+5 - Enhancing capabilities of developing countries to perform dynamic functional studies using radionuclides/Nuclear Medicine/Aerosol inhalation imaging

EARTH SUMMIT+5
Special Session of the General Assembly to Review and Appraise
the Implementation of Agenda 21
New York, 23-27 June 1997
PROGRAMME FACT SHEETS

Enhancing capabilities of developing countries to perform dynamic functional studies using radionuclides/Nuclear Medicine/Aerosol inhalation imaging

Location South and South East Asia region covering 10 countries via Bangladesh (Dhaka), China (Beijing), India (Bombay), Indonesia (Bandung), Japan (Sendai), Korea (Seoul), Pakistan (Lahore), Philippines (Manila), Singapore, Thailand (Bangkok).
Responsible Organization(s) International Atomic Energy Agency (IAEA), Division of Human Health/Nuclear Medicine Section/G. Nair

Description The Subprogramme Nuclear Medicine aims at promoting nuclear medicine techniques to address issues related to health care such as prevention, diagnosis and treatment of common and more prevalent diseases at both individual and community level. In doing so careful attention is given to cost effectiveness, quality assurance and clinical appropriateness of procedures, products and services in nuclear medicine.

Issues addressed Urban air pollution resulting from rapid industrialisation and urbanisation is well known to be a health hazard. Two aspects of this require careful attention and study; how pollution in the air causes increased morbidity and mortality in susceptible population; and setting up standards of air quality by arriving at realistic threshold limits for injurious polllutants(s).
Availability of pollution specific biomarkers can help in arriving at more realistic threshold limits for setting up standards and in understanding the etiopathogenesis of increased morbidity and mortality during heightened episodes of air pollution in megacities.

Objectives The objective of this programme activity was to examine the correlation between inhaled air pollutants prevailing in various cities as mentioned earlier and the lung epithelial permeability of healthy non-smoking residents of these cities.
Lung clearance half-time of inhaled radioactive aerosol (Tc 99m DTPA aerosol) is considered as an indicator of lung epithelial integrity, shorter half times indicating injury to lung epithelium.

Results achieved Inverse correlation was seen between lung clearance half time and individual pollutants, the results in the case of dust load (total suspended particulate matter-TSPM) being the most significant. T1/2 values in subjects ranged from about 45 minutes in highly polluted cities to about 60 minutes in cleaner cities. A multivariate regression fit including TSPM, SO2, NO2 and CO gave satisfactory matching of the predicted and observed T1/2 values. It is concluded that radioaerosol clearance time can serve as a sensitive biomarker of pulmonary epithelial membrane change due to air pollutants especially TSPM.

Lessons learned There is an immense possibility of arriving at more meaningful estimates of limits for suspended particulate matter in defining air quality standards i.e. threshold value for the onset of alveolar microvascular injury can be specified, given that the preliminary results obtained from this exploratory study are validated by a more expanded study.

Financing From the reular budget of IAEA.

Contact G. Nair, Head, Nuclear Medicine Section
Division of Human Health
P.O. Box 100
IAEA
A-1400 Vienna
Austria

Copyright © United Nations
Department of Economic and Social Affairs
Comments and suggestions: esa@un.org
1 November 1997

	Enhancing capabilities of developing countries to perform dynamic functional studies using radionuclides/Nuclear Medicine/Aerosol inhalation imaging
	Location	South and South East Asia region covering 10 countries via Bangladesh (Dhaka), China (Beijing), India (Bombay), Indonesia (Bandung), Japan (Sendai), Korea (Seoul), Pakistan (Lahore), Philippines (Manila), Singapore, Thailand (Bangkok).
	Responsible Organization(s)	International Atomic Energy Agency (IAEA), Division of Human Health/Nuclear Medicine Section/G. Nair
	Description	The Subprogramme Nuclear Medicine aims at promoting nuclear medicine techniques to address issues related to health care such as prevention, diagnosis and treatment of common and more prevalent diseases at both individual and community level. In doing so careful attention is given to cost effectiveness, quality assurance and clinical appropriateness of procedures, products and services in nuclear medicine.
	Issues addressed	Urban air pollution resulting from rapid industrialisation and urbanisation is well known to be a health hazard. Two aspects of this require careful attention and study; how pollution in the air causes increased morbidity and mortality in susceptible population; and setting up standards of air quality by arriving at realistic threshold limits for injurious polllutants(s). Availability of pollution specific biomarkers can help in arriving at more realistic threshold limits for setting up standards and in understanding the etiopathogenesis of increased morbidity and mortality during heightened episodes of air pollution in megacities.
	Objectives	The objective of this programme activity was to examine the correlation between inhaled air pollutants prevailing in various cities as mentioned earlier and the lung epithelial permeability of healthy non-smoking residents of these cities. Lung clearance half-time of inhaled radioactive aerosol (Tc 99m DTPA aerosol) is considered as an indicator of lung epithelial integrity, shorter half times indicating injury to lung epithelium.
	Results achieved	Inverse correlation was seen between lung clearance half time and individual pollutants, the results in the case of dust load (total suspended particulate matter-TSPM) being the most significant. T1/2 values in subjects ranged from about 45 minutes in highly polluted cities to about 60 minutes in cleaner cities. A multivariate regression fit including TSPM, SO2, NO2 and CO gave satisfactory matching of the predicted and observed T1/2 values. It is concluded that radioaerosol clearance time can serve as a sensitive biomarker of pulmonary epithelial membrane change due to air pollutants especially TSPM.
	Lessons learned	There is an immense possibility of arriving at more meaningful estimates of limits for suspended particulate matter in defining air quality standards i.e. threshold value for the onset of alveolar microvascular injury can be specified, given that the preliminary results obtained from this exploratory study are validated by a more expanded study.
	Financing	From the reular budget of IAEA.
	Contact	G. Nair, Head, Nuclear Medicine Section Division of Human Health P.O. Box 100 IAEA A-1400 Vienna Austria