Issues in Global Health: An Investigation of Respiratory Health Effects of Air Pollution in Durban, South Africa

1
Issues in Global Health An Investigation of
Respiratory Health Effects of Air Pollution in
Durban, South Africa

• Thomas Robins, MD, MPH

2
Issues in Global Health An Investigation of
Respiratory Health Effects of Air Pollution in
Durban, South Africa

• Some themes to keep in mind during the
  presentation
• Why are health issues in the developing world
  important to study?
• When and how can effective studies be carried out
  in challenging situations with limited resources?
• How can studies of respiratory morbidity
  associations with environmental pollution be
  designed to give valid useful results?

3
Overview of Presentation

• Who was involved in the study and how was it
  funded?
• What was the purpose of the study?
• How was the study carried out?
• What did we learn about
• Pollutant sources and levels?
• Current health of the participants?
• Health effects of air pollution?
• What conclusions did we reach?
• What recommendations do we have?

4
Team Of Investigators
University of Natal Faculty of Medicine Barry
Kistnasamy, MBChB, Dean Rajen Naidoo, MBChB,
Head, Occupational Health Unit Umesh Lalloo,
MBChB, Head, Department of Medicine Elvis Irusen,
MBChB, Department of Medicine (now at University
of Stellenbosch) Caron Jack, Department of
Medicine Prem Ramlutchman, Department of
Medicine Natasha Maistry, Office of the Dean
5
Team Of Investigators
Durban Institute of Technology Joy Kistnasamy,
Lecturer, Environmental Health Nitasha Baijnath,
Environmental Health University of Michigan,
USA Thomas G. Robins, MD, MPH, Professor,
Environmental Health Sciences Stuart Batterman,
PhD, Professor and Associate Chair, Environmental
Health Sciences Graciela Mentz, PhD, Department
of Statistics Heinrich Amsterdam (visiting from
Pentech)
6
Collaborators
Settlers Primary Environment Committee South
Durban Community Environmental Alliance
ECOSERV Ethekwini Municipality Health
Department Ethekwini Municipality Water
Department Dr. Barry Seetharam Prof. Prakash
Jeena
7
Funding Sources
groundWork Ethekwini Municipality Health
Department University of Natal Durban Institute
of Technology Fogarty International Center,
USA University of Michigan, USA Medical Research
Council Engen SAPREF
8
Background

• A legacy of Apartheid era policies lack of
  zoning of industrial development
• South Durban has two large international
  refineries, a paper mill, an international
  airport, a chemical tank farm, a number of
  landfill sites and various mills, processing and
  manufacturing industries
• All in close proximity to residential and
  recreational areas

9
Background

• Long history of community groups raising
  concerns South Durban Community Environmental
  Alliance (SDCEA) at the school, Settlers Primary
  Environmental Committee (SPEC)
• Specific responses of governmental agencies
  industries

10
Background (Cont.)

• SO2 Committee (tripartite)
• continuous monitoring of SO2 at the school since
  June 2000
• continuous monitoring of oxides of nitrogen,
  carbon monoxide, total reduced sulfurs, and PM10
  since October 2000
• No previous studies of exposure-health outcome
  associations
• Current government request for tenders for larger
  study ZAR 6 million

11
What Was The Main Purpose Of The Study?

• To look at whether air pollution is causing
  breathing problems amongst students and teachers
  at the School

12
Settlers Primary School
13
Settlers Primary School (Cont)
14
Research Questions

• How many learners and teachers at the Settlers
  School have chronic respiratory symptoms and
  conditions, including asthma?
• Do air pollutants measured at the Settlers School
  affect respiratory symptoms and breathing
  function among students and teachers?
• Do those with asthma or other respiratory
  diseases suffer more from air pollution?

15
Research Questions (continued)

• Which pollutants cause these health problems?
• What are the sources of these pollutants?
• What steps should be taken to improve the health
  of students teachers? Of the larger community?

16
How Was The Study Carried Out?

• Exposure assessment
• Levels in the air of several pollutants were
  measured on the school grounds during an 18-day
  period, 19 April 6 May, 2001.

17
Durban Metro Area, SO2 Monitoring Sites
18
Air Quality Monitoring at School
19
Inside Monitoring Van
20
Monitored Air Pollutants
21
How was the study carried out?

• Recruitment of Participants. All teachers, all
  students in grades 3 and 6, and some students in
  grades 5 and 7, were invited to participate in
  the study.
• More than 90 of those invited did participate
  the participants included 248 students and 25
  teachers.
• The baseline health of the participants was
  looked at by using
• parent and child interviews
• breathing function tests including a special test
  called methacholine challenge to look for
  asthma

22
How was the study carried out?

• Also, participants were asked to complete
• each evening at home a daily diary of symptoms
• every two hours while at school
• a symptom log
• blow into a handheld monitor which measures
  breathing function

23
Bi-Hourly Symptom Activity Log
24
AirWatch? Lung Function Monitoring Device

25
How was the study carried out?

• The relationships between exposure to air
  pollutants such as sulphur dioxide (SO2),
  particles (PM10), and nitrogen dioxide (NO2) and
  symptoms and breathing function while at school
  were looked at.

26
Monthly Trends of Sulfur Dioxide at the Settlers
School
What did we learn? Exposure Assessment
27
Long term Pollutant Trends Sulfur Dioxide
28
Daily Trends of SO2 During Study Period
29
Diurnal Trends of SO2 During Study Period
30
Comparison of Measured Pollutants to Standards
Guidelines
31
Summary of Pollutant Measurements

• We focused on monitoring at the Settlers School
  for the study period in April May, 2001.
• Pollutant levels vary by season, time-of-day,
  location and pollutant. Monitoring at the
  school provides only an approximate indication of
  pollutant exposure.
• At the Settlers School during the study period,
  pollutant levels were below guideline levels
• Historically, pollutants have exceeded guideline
  levels
• Looking at the long term trends, levels appear to
  be decreasing for one pollutant, sulfur dioxide.
• Long term data on other pollutants is not
  available.

32
Figure 19. Distribution of asthma severity from
parent baseline interview among students in
grades 3 and 6.(n147 students)
What did we learn? Health Status of Participants
 

•  
•  

 
33
Figure 20. Student asthma severity from the
baseline parent interview by various demographic
variables among students in grades 3 and 6. (Part
I) (average n143 students)
34
Figure 21. Student asthma severity from the
baseline parent interview by various demographic
variables among students in grades 3 and 6.
(Part II) (average n162 students)
35
Figure 23. Distribution of methacholine
challenge test results among students in grades 3
and 6.(n204 students).