An introduction to the effects of pollution on human health

1. Mike Slater

2. Content
Sources of pollution
How pollutants can affect humans
Examples of common pollutants and their effects

3. http://www.slideshare.net/mikeslater
michael.slater@manchester.ac.uk
http://diamondenv.wordpress.com
Twitter @diamondenv

8. Source: http://www.who.int/quantifying_ehimpacts/global/envrf2004/en/index.html

9. Source: http://www.who.int/quantifying_ehimpacts/global/envrf2004/en/index.html

10. The effects of pollution on
human health can be
Direct
Indirect

11. The effects of pollution on
human health can be
Immediate
Delayed

12. Paracelsus (1493-1541)
"All substances are
poisons ; there is none
which is not a poison.
The right dose
differentiates a poison
from a remedy"

13. Risk is the likelihood that harm
will occur in practice
RISK = Hazard x Exposure

14. Exposure to Pollutants
Air pollution
Settlement
Direct inhalation
Rain
animals
Food
Ground pollution
drinking water
& fish
Water pollution
Plants

15. Routes of Entry

16. Routes of Entry
Inhalation

17. Routes of Entry
Inhalation
Ingestion

18. Routes of Entry
Inhalation
Ingestion
Skin contact

19. Distribution
and storage
Absorption Elimination
Biotransfromation

20. Distribution
and storage
Absorption Elimination
Biotransfromation

21. Inhalation
Gases
Aerosols

22. Head Airways Region

23. Tracheo-bronchial Region

24. Gas Exchange Region

25. 100
Total
Deposition Fraction relative
to ambient aerosol (DF, %)
80 Extrathoracic
Tracheobronchiolar
60
Alveolar
40
20
0
0.001 0.01 0.1 1 10 100
Particle Diameter (Dp, micrometer)

26. ISO Criteria for Dust
120
Inhalable
100
Thoracic
80 Respirable
% retained
60
40
20
0
1 10 100
Aerodynamic diameter (um)

27. EN 12341:1998
PM10 - A target specification for sampling thoracic particles
120
100
80
cummulative %
60
40
20
0
0 2 4 6 8 10 12 14 16
Aerodynamic diameter (microns)

28. PM2.5
“mass per cubic metre of particles passing
through the inlet of a size selective sampler
with a transmission efficiency of 50% at
an aerodynamic diameter of 2.5
micrometres”

29. Contribution to primary PM2.5 emissions
in the EU-15, year 2020
http://dataservice.eea.europa.eu/atlas/viewdata/viewpub.asp?id=1838 accessed 17/11/09

30. The
Skin
bfcfranco's @flickr

32. Many organic compounds are
readily absorbed through the skin
solvents
pesticides
organo-metal
compounds

33. Ingestion can occur due to:
 Foodstuff
contamination
 Drinking water
contamination

34. Distribution
and storage
Absorption Elimination
Biotransfromation

35. Distribution
Transport by
blood
Substances
released from
storage

36. Storage
 Fat
 Bones
 Blood
 Liver and kidney
 Other organs / tissues

37. Dioxin and PCP trends in mothers milk monitored in Sweden
http://dataservice.eea.europa.eu/atlas/viewdata/viewpub.asp?id=1843

39. Distribution
and storage
Absorption Elimination
Biotransfromation

40. Biotransformation
 Occurs mainly in
the liver
 Also in lungs,
kidney & intestine

41. Biotransformation
Phase I reactions
• Oxidation
• Reduction
• hydrolysis
Phase II reactions
• Conjugation
• Synthesis
Metabolites Elimination

42. Biotransformation
Sometimes biotransformation
increases toxicity

43. Distribution
and storage
Absorption Elimination
Biotransfromation

44. Excretion
Kidney
 urine
 water soluble
compounds

45. Excretion
Lungs
 volatile
compounds
 gaseous
metabolites

46. Excretion
Liver
 bile
 fat soluble
compounds

47. Excretion
Other routes
 Hair
 Nails
 Skin
 Sweat
 Milk

48. Biological Half Life - time taken for half the
amount of the substance absorbed to be excreted
150
100
Body burden
50
0
0 20 40 60 80 100 120
time

49. Some Half Lives
Toluene ~ 10 hours
Selenium ~ 10 days
Mercury ~ 6 weeks
Lead ~ 10 years or more

51. Site of Effect
Local At site of contact
Systemic Following distribution

52. Types of Effect
chronic
sub-chronic
timescale
sub-acute
acute

53. The effect experienced depends on
the dose
Blood Alcohol Conc. Effect
g/100ml
0.01 - 0.05 Subclinical
0.032 - 0.12 Euphoria
0.09 - 0.25 Excitement
0.18 - 0.30 Confusion
0.25 - 0.40 Stupor
0.35 - 0.50 Coma
0.45 + Death

54. Dose - Effect

55. Susceptibility
 Variation in susceptibility
between individuals

56. Susceptibility
 Different doses required
to produce same effect

57. Susceptibility
 The most susceptible
groups include
 Elderly,
 Children,
 People with pre-existing
disease

58. Susceptibility
 Inter-species variation

59. Dose - Response

60. Dose - Response
Threshold Dose

61. LD50 – Median Lethal Dose

62. Some LD50s
mg/kg body weight
 ETHYL ALCOHOL 7060
 SODIUM CHLORIDE 3000
 NAPHTHALENE 1760
 FERROUS SULFATE 1500
 ASPIRIN 1000
 FORMALDEHYDE 800
 AMMONIA 350
 CAFFEINE 192
 PHENOBARBITAL 150
 CHLORPHENIRAMINE MALEATE 118
 DDT 100
 STRYCHNINE SULFATE 2
 NICOTINE 1
 DIOXIN 0.0001
 BOTULINUS TOXIN 0.00001

63. Pollution
Effects on Human Health
Direct effects
Indirect effects

64. Source: http://www.who.int/globalchange/environment/en/index.html

65. Without effective responses,
climate change will compromise:
Water quality and quantity
Food security
Control of infectious disease
Protection from disasters

66. Chemicals in the Environment
Chemical reactions
Photochemical reactions
Biological transformation
Bioaccumulation

67. Exposure to Pollutants
Mixed
Concentration Accumulation
exposures

68. Evidence for Effects of Pollution
Animal experiments
Human volunteer studies
Epidemiological evidence

69. Irritation
Billablubb@Flickr

70. Irritation
Megyarsh@Flickr

71. Irritation
Jess and Colin@Flickr

72. Corrosive
Destroys tissue
Leo Reynolds@Flickr

73. Chronic obstructive pulmonary
disease (COPD)
 Chronic bronchitis
 Emphysema

74. Emphysema

75. Asthma

76. Sensitisers
Cause allergic
reaction in
susceptible
individuals

77. Sensitisers
Cannot identify
susceptible
individuals!

78. Sensitisers
Develops
gradually

79. Sensitisers
Not always easy
to identify
causative agent

80. Cancer
Unregulated
growth and
proliferation of
cells

81. Carcinogens
Long latency
period

82. Latency Periods
Site Agent Average Range
(years) (years)
Skin Arsenic 25 4-46
Coal tar and pitch 20 1-50
Solar radiation 25 15-40
Lung Asbestos 18 15-48
Blood Benzene 3-19
Bladder Aromatic amines 15 2-40

83. Mutagens
Teratogens
Systemic effects

84. Toxicological Interactions
Independent
Additive
Synergistic
Potentiation
Antagonism

85. London 1952

87. “Higher levels of
PM(10) and NO(2),
which are typically
markers of traffic
related pollution,
seem to be associated
with transiently
increased risk of
myocardial infarction
1-6 hours after
exposure,..”
BMJ. 2011 Sep 20;343:d5531.
Bhaskaran et al

88. “.. air pollution may
be associated with
bringing events
forward in time
("short-term
displacement") rather
than increasing overall
risk. ”
BMJ. 2011 Sep 20;343:d5531.
Bhaskaran et al

90. There are two main sources of
evidence for the effects of
pollutants

91. There are two main sources of
evidence for the effects of
pollutants
Animal
experiments

92. There are two main sources of
evidence for the effects of
pollutants
Epidemiology

93. Problems with animal
experiments

94. Problems with animal
experiments
Inter-species
variation

95. Problems with animal
experiments
They evaluate:
acute effects from
high doses of
single substances
over a short period

96. Problems with animal
experiments
Ethics

97. Problems with epidemiological
studies

98. Problems with epidemiological
studies
Simultaneous
exposure to many
environmental
pollutants

99. Problems with epidemiological
studies
Other exposures to
chemicals

100. Problems with epidemiological
studies
Other confounders
such as
• temperature,
• smoking

101. Problems with epidemiological
studies
Low level effects
are difficult to
quantify

104. Air pollution is estimated to cause
1,152,000 deaths per year worldwide
Source: World Health Organisation (2006) Preventing disease
through healthy environments: Towards an estimate of the
environmental burden of disease

109. http://www.defra.gov.uk/environment/statistics/globatmos/gagccukem.htm

110. Source: http://www.who.int/globalchange/environment/en/index.html

111. Carbon Monoxide
Chemical asphyxiant

112. Sulphur dioxide
Sulphur dioxide

113. Sulphur dioxide
http://www.defra.gov.uk/environment/statistics/airqual/kf/aqkf20.htm

114. Sulphur Dioxide - Effects
Soluble acid gas
Upper respiratory tract
irritation

115. Sulphur Dioxide - Effects
Increased effect on people
with pre-existing
respiratory disease

116. Indirect effect from
sulphur dioxide :
“acid rain”

117. http://www.defra.gov.uk/environment/statistics/airqual/aqemnox.htm

118. Nitrogen Dioxide
Deep lung irritant
Less evidence for
effect on pre-existing
conditions

119. Nitrogen oxides, as acidic
Gases can also contribute
To “acid rain”

120. VOCs
http://www.defra.gov.uk/environment/statistics/airqual/kf/aqkf23.htm

121. VOCs - Direct effects
Depends on
compound

122. VOCs - Indirect effects
Photochemical ozone
formation
Ozone depletion
Climate change

123. Ozone Depletion
Reduced stratospheric ozone
CFCs
Chlorohydrocarbons
Immune
system Skin
cancer Cataracts
supression

124. Ozone
Produced by
photochemical reactions
Deep lung irritant

125. Ozone - Acute effects
Reduced lung function
Aggravates asthma
Damages lining of respiratory
passages

126. Ozone - Chronic effects
Permanent reduction in
lung function?

127. Fig 2
Estimated number of acute adverse health effects
avoided by meeting the 1997 US EPA Ozone Ambient Air
Quality standard
Source: Journal of Allergy and Clinical Immunology 2005; 115:689-699 (DOI:10.1016/j.jaci.2005.01.056 )

128. Particulate Matter

130. PM2.5
Approximates the
respirable fraction

131. PM2.5
“mass per cubic metre of particles passing
through the inlet of a size selective sampler
with a transmission efficiency of 50% at an
aerodynamic diameter of 2.5 micrometres”

132. Contribution to primary PM2.5 emissions
in the EU-15, year 2020
http://dataservice.eea.europa.eu/atlas/viewdata/viewpub.asp?id=1838 accessed 17/11/09

133. Premature deaths attributed to PM2.5, 2005
(attributable annual mortality per 10 000 people)
Source: WHO (2010)
Health and Environment in
Europe: Progress Assessment

134. Particulate Matter
Acute Effects Chronic Effects
Lung inflammatory reactions Increase in lower respiratory
symptoms
Respiratory symptoms Reduction in lung function in
children
Adverse effects on the Increase in chronic obstructive
cardiovascular system pulmonary disease
Increase in medication usage Reduction in lung function in
adults
Increase in hospital admissions Reduction in life expectancy
Increase in mortality
Source: Health aspects of air pollution: Results from the WHO project "Systematic review of health
aspects of air pollution in Europe" (WHO, 2004)

135. ISSN 1047-3289 J. Air & Waste Manage. Assoc. 56:709–742

139. Lead concentrations in childrens blood, and
lead in petrol (tonne) sold in Sweden 1976-2003.
Lead (Pb) in blood in children, 3-12 years of age, in relation to Pb in petrol, tons
per year
1800 70
1600
60
1400
Pb in petrol, ton
Pb in blood, µg/l
50
1200
1000 40
800 30
600
20
400
10
200
0 0
1976 1980 1984 1988 1992 1996 2000 2004
Year
Pb in petrol sold in Sweden Pb in blood, children 3-12 years of age
http://dataservice.eea.europa.eu/atlas/viewdata/viewpub.asp?id=1845

140. Change in mercury concentration in human
and animal hair from Greenland
http://dataservice.eea.europa.eu/atlas/viewdata/viewpub.asp?id=1842

141. Water and
Land Pollution

145. Mercury - The Minamata Incident
Minamata
Bay, Japan,
1950s
Chisso
Corporation

146. Mercury - The Minamata Incident
Inorganic mercury discharged
Biotransformed to
methylmercury
Bioaccumulation in fish
Ingestion by humans

148. Initial Symptoms
Peripheral sensory loss
Delirium
Disturbed speech, vision
and hearing
Disturbed gait

149. Severe Cases
General paralysis,
involuntary movements
Convulsions
Death

150. Camelford Incident
 1988, Camelford, Cornwall
 Aluminium sulphate contamination of
water supply

151. Short term effects
Nausea
Vomiting
Mouth ulcers
Skin rashes

152. Longer term effects
Memory loss?
Effects on cerebal function?

153. Source: Arsenic in groundwater: testing pollution mechanisms for sedimentary aquifers in Bangladesh.
J.M. McArthur, P. Ravenscroft, S. Safiullah and M.F. Thirlwall. Water Resources Research

154. Effects of Arsenic Pollution
Skin
 keratonosis
 Melanosis

155. Effects of Arsenic Pollution
Gastrointestinal disturbances
Cancer

156. http://www.slideshare.net/mikeslater
michael.slater@manchester.ac.uk
http://diamondenv.wordpress.com
Twitter @diamondenv

157. Websites
 US National Library of Medicine Toxicology Tutor
 http://sis.nlm.nih.gov/enviro/toxtutor.html
 UK DEFRA air quality statistics
 http://www.defra.gov.uk/environment/statistics/airqual/aqemissions.htm
 European Environmental Agency report – “Europe's environment: the
third assessment - Chapter 12 - Environment and human health”
 http://reports.eea.europa.eu/environmental_assessment_report_2003_10/Chapter12
 European Environmental Agency report “Environment and Health”
 http://reports.eea.europa.eu/eea_report_2005_10/en
 WHO Systematic review of health aspects of air pollution in Europe
 http://www.euro.who.int/eprise/main/WHO/Progs/AIQ/activities/20030528_3
 Committee on the Medical Effects of Air Pollutants (COMEAP)
 http://www.dh.gov.uk/ab/comeap/index.htm
 Video on Minamata incident
 http://science.education.nih.gov/supplements/nih2/chemicals/activities/lesson5.htm