GLOBAL ENVIRONMENT MONITORING SYSTEM ASSESSMENT OF URBAN AIR QUALITY SITED NATIONS WORLD HEALTH 'VIRONMENT PROGRAMMF Eel., io, ORGANIZATION Copyright © UNEP and WHO 1988 Prepared in cooperation with the Monitoring and Assessment Research Centre, London 77 GLOBAL ENVIRONMENT MONITORING SYSTEM SSESSMENT OF URBAN AIR QUALITY U'ilTED NATIONS WORLD HEALTH ENVIRONMENT PROGRAMME ORGANIZATION Preface Ever since the mid-1970, the World Health Organization (WHO) in collaboration with the United Nations Environment Programme (UNEP) has, through the Global Environment Monitoring System (GEMS), been operating worldwide networks for monitoring air and water quality and with the Food and Agriculture Organization (FAO) for food contamination, and collecting information on environmental conditions and human exposures in different parts of the world. In 1988 this information, supplemented with other data, was compiled and analysed and for each topic an assessment was made on the global and regional levels and trends. These assessments were considered and endorsed by a government-designated Expert Meeting which was held in Geneva from 12-16 September 1988. 7imendments proposed at the Expert Meeting were incorporated into the assessment reports. The UNEP/WHO Meeting was attended by delegates from 12 countries (Australia, Brazil, Canada, China, Egypt, Ghana, Hungary, India, Japan, The Netherlands, Sudan, U.S.A.), two international organizations (the Food and Agriculture Organization (FAQ) and the World Meteorological Organization (WMO)) and the Monitoring and Assessment Research Centre (MARC). The government-designated Expert Meeting was chaired by Dr. Abmed Amin El-Carnal, Advisor, Egyptian EnvIronment Agency, with Dr. Vic Armstrong, Head, criteria Section, Environment Health Directorate, Health and Welfare, Canada, serving as Rapporteur. In addition to the review of the assessment reports, the Government Experts also made recommendations concerning the ways in which the monitoring programmes and future assessments might be improved. These recommendations are reflected in the report of the meeting. This report contains an assessment of urban air quality. Similar assessments on chemical contamination in food and freshwater quality are presented in separate companion documents entitled Assessment of Chemical Contaminants in Food" and "Assessment of Freshwater Qiiality" respectively. ASSESSMENT OF tTRBAN AIR QUALITY CONTENTS Page IDIJCTION . ......... .. ...... ... 3 SOURCES, EFFECTS AND CONTROL OF AIR POLLUTION . ... ... ... S 2.1 Background.. ... .• * ... ......... • . ....... 5 2.2 Scope of present report .......... .. .. ...... & • 6 2.3 Health effects of air pollution. ..• .. ....... 7 2.4 Socio-economic factors affecting air pollution. ... 8 2.5 Strategies to control air pollution .. ... ... ....... 10 SULPHtJR DIOXIDE. ... • . ........... ... ..... 11 3.1 Origins and properties ... .•. ... .. .......• 11 3.2 Trends in S02emissions .................... 11 3.3 Trends in SO 2 am:bient levels .. ... ......... 15 3.4 SO2 concentrations in cities .. ...... .. •.. 16 3.5 Comparison with guidelines. ........ ...... ... ... 18 3.6 Evaluation of high pollution days ... .. ........ 18 3.7 Estimation of population exposures ... ...... .•. 20 3.8 Case studies from individual countries ... ... ...... 20 3.8.1 Norway ... ......... ... ........ • 20 3 • 8.2 United Kingdom. ... • . ....... ... 21 3.8.3 Hungary... ... •.. ...... ... ... ... ... 23 3.8.4 Hong Kong. ......... .. ... ....... ... 24 SUSPENDED PARTICULATE MATTER . .......... ... ....... 25 4 .1 Sources ... ... ... ......... ... ....... • 25 4.2 Determination and properties of suspended particulate matter • 25 4.3 Trends in particulate emissions. ... ... ....... • 26 4.4 Trends in ambient particulate levels . ... ... ... 27 4,5 Particulate concentrations in cities . ... ... ... 28 4.6 Comparison with guidelines....... .•. ........ 31 4.7 Evaluation of high pollution days ... ........• 32 4.8 Estimation of population exposures ... ... ... ... ..... 34 4.9 Case studies from individual countries ...... ... ... ... 34 4.9.1 The United States of America.. .. .... ... ... 34 4 • 9.2 The United Kingdom. ... ........ ... 35 4.9.3 Greece ... ... ... ..• * 4* •• ... ... ... ••• 37 4.9.4 China ......... ... ... ......... 38 NITROGEN OXIDES ......... ... .......... ... 39 5.1 Sources and properties ........................ 39 5.2 Trends in NO emissions ............... 40 5.3 Trends in ambient NO2 levels ... ........... 41 5.4 NO2 concentrations in cities ........ .. ... •.• 0.. 43 5.5 Comparison with guidelines ... ..• ••. ...... 47 5.6 Estimation of population exposures.. ... .•. ...... 48 5.7 Case studies from individual countries. ........ 48 5.7.1 The Netherlands ......... ...... ...... ... 48 5 .7.2 Canada... ... ... •.. ... ... ..• ... •.• .•• 49 5 . 7 • 3 Hong Kong ....... • . ........• • . • 51 -2- 6 • CARBON MONOXIDE ... ... ... 52 6.1 Sources and properties ............ 52 6.2 Trends in CO emissions ... ... ... ............. 52 6.3 Trends in ambient CO levels ... • ................ 54 6.4 CO concentrations in cities ... ... 55 6.5 Comparison with guidelines ............ 56 6.6 Estimation population exposures ... ... ... ... ... ... 57 6.7 Case studies from individual countries 57 6.7.1 The United States of l%merica 57 7 . LEAD ... ••• ... ••• •• ...................... 58 7.1 Sources and properties ... ... ... .• .......... 58 7.2 Trendsinleademissions.. ... ... 59 7.3 Trends in ambient lead levels.. ... ., ., 61 7.4 Lead concentrations in cities .................. 61 7.5 Comparison with guidelines .................. 63 7.6 Estimation of populations exposures. .... ... ... ... 64 7.7 Case studies from individual countries 65 7.7.1 The United Kingdom. ... ... ... ... ... 65 7.7.2 The United States of America. ... ... ... ... 66 7.7.3 Norway ............... • 68 8. GLOBAL ASSESSMENT AND EMERGING ISSUES .................. 70 8.1 Emissions and ambient air pollution levels in cities ... 70 8.2 Health implications .. ... ... ... .•• 71 8.3 Information gaps and need for further work ............ 73 8 • 3 • 1 Emissions . ... • . 00. ... ... ... ... 73 8 3.2 Monitoring ......... ..• ... ... ... • . 73 8.3.3 Exposure ... ... ... ... ... .....• 0..• 74 8.4 Issues requiring further attention .. ... ... ... ... ... 75 9. REFERENCES ... ...... ... ... ... ... ... 77 9.1 General ,.. ..• ..• ... ••. S ................ 77 9.2 GEMS/Air ............ ... ... .•* 79 APPENDIX I INDOOR AIR QUALITY ........................• 81 1. Nature oftheproblem. ... ... ... ... ... ... 81 2. Indoor air pollution in industrialized countries ... 82 3. Indoor air pollution in developing countries ... ... ... 84 4. Indoor concentrations of pollutants, as reported from developing and developed countries. ... ... 85 APPENDIX II EMISSION ESTIMATES ... ... ....... ... ... ... 89 Tablel - Suiphurdioxide. ... ... ... ... ... ... ... 90 Table 2 - Suspended particulate matter... 91 Table 3 - Nitrogen dioxide .............. 92 Table 4 - Carbon monoxide ... ... ... 93 Table 5 - Lead ..................... .. .. 94 APPENDIX III EXCEEDANCE OF 98 PERCENTILE ... ..• 97 Table 1 - Number of days per year with S02 levels above 150 ugJn3 for the 1980-1984 period ... 98 Table 2 - Number of days per year with smoke levels above 150 ug/m3 for the 1980-84 period ... ... ... ... ..• 99 Table 3 - Number of days per year with gravimetrically determined SPM levels above 230 ug/ 3 for the 1980-84 period .. ... ... ... ... ... ... ... .•. ......100 MM I. INTRODUCTION WHO and UNEP have been collaborating since 1974 on a project on air moni- toring in urban areas. Referred to as GEMS/Air, the project forms part of the Global Environment Monitoring System (GEMS). GEMS is the collective effort to monitor the world environment in order to protect human health and preserve essential natural resources. The coordination centre for GEMS was established within the United Nations Environment Programme in 1975. The scope of GEMS, however, extends beyond projects supported by UNEP. In over 30 international monitoring projects implemented by UNEP, WHO, WMO, FAO, UNESCO and other United Nations and Inter-Governmental Organizations, national activities in countries worldwide are strengthened and united under the GEMS umbrella. Quality and comparability of data are stressed to provide useful input for assessments of environmental conditions. The monitoring covers climate, health, terrestrial natural resources, the oceans and long-range transport of pollutants. The monitoring and assessments are conducted to guide the rational manageTentof our world environment. As part of the Health Related Environmental Monitoring Programme, GEMS/Air is active in some 50 countries of which about 35 provide representative data sets for major urban areas for suspended particulate matter and sulfur dioxide. Figure 1.1 shows the current network of cities participating in GEMS/Air. Figure 1.1 Location of GEMS/Air monitoring stations •r:. D. ..- .. ., .__) it'. •X--..1 - ~ - •t*I - _f- .-, ) _•- 1 - r : ••'y _t ------1'_ The GEMS/Air cities were selected to provide as broad a global coverage as possible. The cities were also chosen to represent different climatic con- ditions, levels of development and pollution situations. In most cities, there are three GEMS/Air monitoring stationss one located in an industrial zone, one in a commercial area and one in a residential area. The data obtained from these stations permit a reasonable evaluation of minimum and maximum levels, and of long-term trends of