Environmental health

Functions of forest

• Evapotranspiration
• Coniferous woods compared to broad leaf deciduous woods have shallower roots which leads to less ability to retain rain falls and land slides

Malaria from view point of environmental change

Africa	SE Asia
Anopheles gambiae complex Anopheles gambiae sensu stricto Anopheles arabiensis Anopheles funestus	Anopheles dirus complex Anopheles minimus complex Anopheles sundaicus complex
Human cases are aggregated in deforested and reclaimed areas uncontrolled land border crossings keep importing/exporting cases	Human cases are aggregated in natural forested areas especially around land border areas

species	distribution	biting preference	resting site	breeding site
Anopheles arabiensis	Africa	livestock	outside	small, open water body = more artificial/deforested/reclaimed area where also provides higher water temp.
Anopheles gambiae s.s.		human	inside house
Anopheles funestus				large vegetated water body = more natural area
Anopheles dirus complex	SE Asia			forested area
Anopheles minimus complex				hilly forested area
Anopheles sundaicus complex				coastal area

Factors affecting malaria endemicity

• Global warming
• Population (density) increase
• Importation of malaria beyond borders (esp. land borders)
• Plasmodium drug resistance
• Degradation of control system
• Land use change
• Intense rainfall by oceanic environmental changes

Air pollution

• Approx. 6 million deaths are attributable to air pollution in 2019

Classification of air pollutants

Primary	Secondary
Carbon compounds CO, CO2, CH4, VOCs Nitrogen compounds NO, N2O, NH3 Particulate matter PM2.5	(NO→) NO2, HNO3 (VOCs→) O3 (gaseous pollutants→) Sufate, nitrates, organic aerosols

Natural source	Anthropogenic source
Wind blown dust, desert dust Pollen, aero-allergens Smoke, fly ash, gases from forest fires Volcanic ash and gases	Industry Transportation system Consumer and commercial product Commercial and residential heating Agriculture, livestock

Temperature inversion

• Air pollutants rise up in higher atmospheric layer and cap/cover a land resulting in that relatively colder air is trapped underneath capping warmer air

Monitoring and sensing

• Ground-based monitoring
  • Real-time Air Quality Index Visual Map
• Remote sensing by satellites
• Personal monitoring by small sensor
• Atmospheric modeling

Health effects by particulate matter

Lung cancer Acute LRI Stroke Ischemic heart disease COPD

Allergic disease? Diabetes? Cognitive dysfunction? Low birth weight? Diarrhea?

How to assess exposures

• Direct
  • Personal monitoring
  • Biological marker measurement
• Indirect
  • Environmental monitoring
  • Mathematical model
  • Questionnaire
  • Diary

Population Attributable Fraction (PAF)

• The fraction of all cases of a particular disease or other adverse condition in a population that is attributable to a specific exposure

[math]\displaystyle{ PAF = \frac{E(RR-1)}{E(RR-1)+1} }[/math] where,

• [math]\displaystyle{ E }[/math] is proportion of exposed among population
• [math]\displaystyle{ RR }[/math] is relative risk of the exposure derived from air pollution mortality function