Hong Kong is a beautiful city Sunday 1 August 2004 Photo: Edward Stokes; Hong Kong Conservation Photography Foundation However, sometimes less so… Tuesday

Hong Kong is a beautiful city

Sunday 1 August 2004Photo: Edward Stokes; Hong Kong Conservation Photography Foundation

However, sometimes less so…

Tuesday 4 January 2005Photo: 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

Department of Community Medicine, School of Public Health, University of Hong Kong


BAD AIR, BAD PRESS


(microgram per cubic meter)

Pollution (RSP)

0

20

40

60

80

100

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


02

04

06

08

01

00

Jan01 Jan02 Jan03 Jan04 Jan05

Monthly concentration of PM10 in year 2001-05

Time

Co

nce

ntr

atio

n (g

/m3 )

RoadsideGeneral

Source: Environmental Protection Department/ Department of Community Medicine HKU

Proposed WHO PM10 (annual) = 20

Hong Kong PM10 AQO (annual) = 55


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


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

1988 1989 1990 1991 1992 1993 1994 1995

020

4060

80

NO2

SO2

O3

PM10

Mic

rogr

am

s pe

r cu

bic

met

re

Year

Fuel restriction on sulphur

50% reduction in SO2 after the intervention

No change in other pollutants


Effect of conversion to low sulfur fuel (0.5%) on transition metals

Time

Conc

entra

tion

05

1015

2025

30

III 85 III 87 III 89 III 91 III 93 III 95

Industrial areasResidential areas

Nickel (Ni)

Time

Conc

entra

tion

020

4060

III 85 III 87 III 89 III 91 III 93 III 95

Industrial areasResidential areas

Vanadium (V)

before=9.48;after =2.87;p =0.000

before=24.73;after =3.95;p =0.000


Reductions in cardiopulmonary deathsafter sulfur restriction 1990

All causes Cardiovascular Respiratory

% R

edu

ctio

n i

n a

nn

ual

tre

nd

-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%


Monthly Trends of SO2, Ni, V in Year 2001-040

10

20

30

40

Jan01 Jun01 Jan02 Jun02 Jan03 Jun03 Jan04 Jun04

Con

cent

ratio

n (S

O2:

mg/

m3 ;

V/N

i: ng

/m3 )

MonthData source: HKEPD; Plotting: Chau/Hedley 2006

p=0.001

p=0.129

p=0.048

SO2

NiV


1970 1975 1980 1985 1990 1995 2000 2005

0

10

20

30

40

50

Hazy daysNumber per year

Year

Source: Hong Kong Observatory

Hong Kong: Annual decline in visibility


An analysis directed to GovernmentLegislators, media and public

Understanding the connection between visibility, air pollution and health costs

in pursuit of accountability, environmental justice and health protection


Visibility and pollutants in Hong Kong

Tsim Sha Tsui to Victoria Harbour Average pollutant levels across Hong Kong

Sunday 1 August 2004

Tuesday 4 Jan 2005

MIC

RO

GR

AM

PE

R C

UB

IC M

ET

ER

Source of data: Environmental Protection Department


Hourly visibility on the days the photographs were taken

Source of data: Hong Kong Observatory

12.8


Four levels of air quality: General and roadside

* Based on general monitoring stations except the background monitoring station at Tap Mun Chau

Level Definition* RSP NO2 SO2

1Poor

The mean of the concentrations on Poor visibility days

129 107 64

145 163 66

2Better

The mean of the concentrations on Better visibility days

25 35 22

45 60 23

3Good

The mean of the minimum concentrations on Better visibility days

16 20 8

23 36 9

4Average

The annual Average of all actual daily concentrations in 2004

61 62 25

80 101 23


Potential improvements in air quality in Hong Kong

0

20

40

60

80

100

(microgram per cubic meter)

Pollution

Hong Kong2004 (62)

Good

Better

Average

average to better

average to good

Poor

% of days at these levels in Hong Kong

2%

8%

44%

43%

2%


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

• 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


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


SO2

NO2RSP

(84%)

(41%)

Correlation between pollutants

Correlation between NO2 and RSP

Partial correlation between NO2 and SO2 adjusted by RSP

Partial correlation between RSP and SO2 adjusted by NO2

(1-[0.768]2) = 0.41 NO2

(1-[0.067]2 – [0.39]2) = 0.84 SO2


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)


Poor

Avoidable events: Deaths

0

20

40

60

80

100

(microgram per cubic meter)Pollution

Hong Kong2004

Good

Better

Average

1,300


Poor

0

20

40

60

80

100


Hong Kong2004

Good

Better

Average

60,000

Avoidable events: Hospital bed days


Poor

0

20

40

60

80

100


Hong Kong2004

Good

Better

Average

6,700,000

Avoidable events: Doctor visits


57

189

0

50

100

150

200

Direct costsProductivity losses

Annual $ Value of air quality improvement

US$ M Total: US$2250MTotal: US$246M

Direct health costs & productivity loss avoided

Intangible costs for pain & suffering

+527

1716

0

500

1000

1500

2000

Deaths

WTP for avoidance of seriouschronic & less serious illness

US$ M


Results of sensitivity analysis on annual avoidable mortality and costs if pollution levels reduce from Average to Good levels

Sensitivity analysisNo. of

avoidable deaths

Direct cost

US$ M

Productivity loss

US$ M

Intangible cost

US$ M

General stations 1,335 189 57 2,250

Single pollutant with the largest effect* for each outcome

860 103 35 1442

RSP + O3 348 136 23 926

SO2 only 600 - - -

Roadside pollutant levels 1,505 198 63 2,435

* Mortality NO2; Admissions NO2; Family doctor visits RSP


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”



02

04

06

08

01

00

1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 2022 2024 2026 2028 2030

Year

mic

rog

ram

s p

er

cub

ic m

ete

r

Non-roadside

Roadside

Reduce 10% in slope

Reduce 20% in slope

Canada guideline (24hr) = 25

NZ guideline (annual) = 20

Non-roadsideReach HK AQO = Year 1996Reach Canada guideline = Year 2026Reach NZ guideline = After year 2031

RoadsideReach HK AQO = Year 2008Reach Canadian guideline = Year 2015Reach NZ guideline = Year 2016

RSP: Projected trends in Hong Kong


THE NEED for EFFECTIVE MULTI-SECTORAL STRATEGIES

• Local and regional sources• Near term technical solutions

Mid term technical prioritiesLong term structural solutions

* Cleaner fuels * Urban design* Euro IV & V * Manufacturing* Flue gas sulpurization * Power sector* Rail rather than roads * Transport


Documents

Hong Kong is a beautiful city Sunday 1 August 2004 Photo: Edward Stokes; Hong Kong Conservation Photography Foundation However, sometimes less so… Tuesday