Hedley

Hong Kong is a beautiful city: 

Hong Kong is a beautiful city Sunday 1 August 2004 Photo: Edward Stokes; Hong Kong Conservation Photography Foundation However, sometimes less so… Tuesday 4 January 2005 Photo: Edward Stokes; Hong Kong Conservation Photography Foundation AIR POLLUTION IN HONG KONG and the PEARL RIVER DELTA AJ Hedley1, SM McGhee1, W Barron2, PYK Chau1, J Chau1, TQ Thach1, TW Wong3, C Loh4, CM Wong1 1 University of Hong Kong 2 University of Science and Technology 3 Chinese University of Hong Kong 4 Civic Exchange

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BAD AIR, BAD PRESS

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(microgram per cubic meter) Pollution (RSP) Vancouver 2004 (13) Shanghai, Guangzhou 2004 (99) London 2005 (30) Paris 2003 (21) New York 2003 (22) Los Angeles 2003 (44) Hong Kong 2004 (62) Hong Kong AQO WHO AQG Hong Kong roadside 2004 (80) HONG KONG IS WORSE THAN MOST CITIES

Monthly concentration of PM10 in year 2001-05: 

Monthly concentration of PM10 in year 2001-05 Time Concentration (mg/m3) Roadside General Source: Environmental Protection Department/ Department of Community Medicine HKU Proposed WHO PM10 (annual) = 20 Hong Kong PM10 AQO (annual) = 55

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Before After On July 1st 1990 the Environmental Protection Department restricted the sulphur content of fuel to 0.5% by weight The Hong Kong air quality intervention 1990 Kwai Tsing

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AIR POLLUTANT CONCENTRATIONS 1988 - 95 IN HONG KONG HALF YEARLY MEAN LEVELS

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Effect of conversion to low sulfur fuel (0.5%) on transition metals mbefore=9.48; mafter =2.87; p =0.000 mbefore=24.73; mafter =3.95; p =0.000

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Reductions in cardiopulmonary deaths after sulfur restriction 1990 All causes Cardiovascular Respiratory % Reduction in annual trend -6 -5 -4 -3 -2 -1 0 15-64 65+ 15-64 65+ 15-64 65+ -1.8% -2.8% -1.6% -2.4% -4.8% -4.2%

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Monthly Trends of SO2, Ni, V in Year 2001-04 Concentration (SO2: mg/m3; V/Ni: ng/m3) Month Data source: HKEPD; Plotting: Chau/Hedley 2006 p=0.001 p=0.129 p=0.048 SO2 Ni V

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Hazy days Number per year Year Source: Hong Kong Observatory Hong Kong: Annual decline in visibility

An analysis directed to GovernmentLegislators, media and public: 

An analysis directed to Government Legislators, media and public Understanding the connection between visibility, air pollution and health costs in pursuit of accountability, environmental justice and health protection

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Visibility and pollutants in Hong Kong MICROGRAM PER CUBIC METER Source of data: Environmental Protection Department

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Hourly visibility on the days the photographs were taken Source of data: Hong Kong Observatory

Four levels of air quality: General and roadside: 

Four levels of air quality: General and roadside * Based on general monitoring stations except the background monitoring station at Tap Mun Chau

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Potential improvements in air quality in Hong Kong 0 20 40 60 80 100 (microgram per cubic meter) Pollution Hong Kong 2004 (62) Good Better Average average to better average to good Poor % of days at these levels in Hong Kong 2% 8% 44% 43% 2%

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Doctor visits, hospital admissions and deaths: Excess risks and avoidable events From time series, excess risks of: * family doctor visits * hospital admissions for cardiopulmonary disease * all causes mortality For each pollutant (P) we estimated the impact (I), as avoidable events for each health outcome, from air quality improvement as NI *ERP *LP = IP Avoidable events and IP * CI = Avoidable costs

UNIT COSTS IN ESTIMATION OF AVOIDABLE COSTS: 

UNIT COSTS IN ESTIMATION OF AVOIDABLE COSTS From gazetted public sector and surveys costs of: * in-patient and ambulatory care * travel costs * productivity loss From surveys, willingness-to-pay to avoid: * symptoms (cough) day * hospital admission * death

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Estimation of health impact and costs: Single or multiple pollutants? In Shanghai, Wuhan and Hong Kong the largest mortality excess risks are for NO2 and SO2, robust in 2-pollutant models The Hong Kong sulfur restriction led to reduction in mortality of 1% per 10µg/m3 SO2 in the absence of change in RSP, NO2 and O3 In Hong Kong the largest effect on hospital admissions for cardiopulmonary disease is associated with NO2; in London with RSP

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Correlation between pollutants Partial correlation between NO2 and SO2 adjusted by RSP (1-[0.768]2) = 0.41 NO2 (1-[0.067]2 – [0.39]2) = 0.84 SO2

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Estimating the total contribution of pollutants to the burden of health effects and costs Main estimate: T = RSP + 0.41 NO2 + 0.84 SO2 + O3 Sensitivity analysis: “At least impact”-highest single pollutant effect for each outcome RSP + O3 (WHO 2003) SO2 intervention effect (mortality)

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Poor Avoidable events: Deaths 0 20 40 60 80 100 (microgram per cubic meter) Pollution Hong Kong 2004 Good Better Average 1,300

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Poor 0 20 40 60 80 100 (microgram per cubic meter) Pollution Hong Kong 2004 Good Better Average 60,000 Avoidable events: Hospital bed days

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Poor 0 20 40 60 80 100 (microgram per cubic meter) Pollution Hong Kong 2004 Good Better Average 6,700,000 Avoidable events: Doctor visits

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Annual $ Value of air quality improvement US$ M Total: US$2250M Total: US$246M Direct health costs & productivity loss avoided Intangible costs for pain & suffering + US$ M

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Results of sensitivity analysis on annual avoidable mortality and costs if pollution levels reduce from Average to Good levels * Mortality NO2; Admissions NO2; Family doctor visits RSP

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THE HKSAR GOVERNMENT RESPONSE “The costs are indirect” “Other cities have worse levels of pollution” “More evidence is needed on health effects” People need to understand that “clearer skies may cost consumers more”

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Canada guideline (24hr) = 25 NZ guideline (annual) = 20 Non-roadside Reach HK AQO = Year 1996 Reach Canada guideline = Year 2026 Reach NZ guideline = After year 2031 Roadside Reach HK AQO = Year 2008 Reach Canadian guideline = Year 2015 Reach NZ guideline = Year 2016 RSP: Projected trends in Hong Kong

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THE NEED for EFFECTIVE MULTI-SECTORAL STRATEGIES Local and regional sources Near term technical solutions Mid term technical priorities Long term structural solutions * Cleaner fuels * Urban design * Euro IV & V * Manufacturing * Flue gas sulpurization * Power sector * Rail rather than roads * Transport

Hong Kong: 1987 Air Quality Objectives: 

Hong Kong: 1987 Air Quality Objectives 0 20 40 60 80 100 Hong Kong AQO 1987 WHO AQG 2006 PM2.5 PM10 /SO2 NO2 Hong Kong (2004) Average Pollutant Levels RSP/NO2 (General) RSP (Roadside) NO2 (Roadside) 150 10 SO2 NO2 PM10 HK WHO

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Reduction in Bronchial Hyper-Reactivity

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Non-roadside Reach Euro guideline = Year 2017 HK Air Quality Objective (annual) = 80 Euro guideline = 40 Roadside Reach HK AQO = Year 2010 Reach Euro guideline = After year 2030 Nitrogen Dioxide

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Visibility and pollutants in Hong Kong MICROGRAM PER CUBIC METER Source of data: Environmental Protection Department