Air

Air

Smog

  • Smog = (smoke + fog) = ground-level ozone
  • Human exposure increased an average of 0.9 %
  • Fine particles causes lung damage
  • Tiny airborne debris from burning fossil fuels, found wherever there are cars, boilers, power plants and fires
  • Particulate matter ≤10 microns (about 0.0004 inch) called PM 10 increases heart and lung disease
  • Smallest particles ≤ 2.5 microns (about 0.0001 inch) known as PM 2.5 found in haze and smoke, make its way deep into the lungs and bloodstream

Causes

  • Air pollution is caused by any particulate matter, chemical, or biological agent that changes the natural characteristics of the atmosphere
  • Toxic compounds in the air can accumulate on hard surfaces and can build up until rain washes it into sewers and creeks
  • Particulate matters are emitted by gasoline-burning motor vehicles and some industries.

 

Effects on Health

  • Exposure to particulate matter has been linked to increased risk of heart problems
  • Breathing in diesel exhaust fumes at levels typically found in large cities disrupts important blood vessel functions, new research has shown, suggesting a potential mechanism linking increased heart attack rates during periods of high air pollution
  • In mice it has been shown that exposure to particulate matter led to accelerated blood clotting, thrombosis, decreased bleeding times, and accelerated blood clotting
  • Nitrogen oxide, fine particles and ground-level ozone are estimated to shorten average life expectancy in Western and Central European countries by almost a year
  • For each decrease of 1 microgram of soot per cubic meter of air, death rates from cardiovascular disease, respiratory illness and lung cancer decrease by 3 percent, thus extending the lives of 75,000 people a year in the United States
  • Particulate matter can evade the body’s defenses, thicken the blood, and is also associated with acute bronchitis in children

 

Effects on Foetus

  • Mothers who had a higher exposure to air pollution had fetuses that were, on average, smaller in terms of abdominal circumference, head circumference and femur length
  • A negative relationship between amount of pollutants, a measure of the distance from source of pollution, and ultrasound measurements of the foetuses, was found and as such lower birth weight is indicative of poorer health later on
  • Babies born to women exposed to high ozone levels during pregnancy are at heightened risk for being significantly underweight
  • Research found that each increase of 12 parts per billion (ppb) of average daily ozone levels over a mother's entire pregnancy was associated with a drop of 47.2 grams (g)-about a tenth of a pound-in a baby's birth weight, also for each 17 ppb increase in average daily ozone levels during a mother's third trimester of pregnancy, the risk of intra uterine growth retardation increased by 20%
  • Each increase of 1.4 parts per million of carbon monoxide concentration during the first trimester was associated with 21.7 g (about .05 pound) decrease in birth weight and a 20 percent increase in risk of intra uterine growth retardation

 

Australia

  • In 2005 the epidemic of chest-pain cases in Sydney, Australia, increased from 5.7/day from 4/day was attributed to high solar radiance and ozone levels where high temperatures increased the risk by 27%, high radiation levels increased the risk by 44% and high ozone levels increased the risk by 13%

 

North America

  • Asthma, the most common chronic disease of childhood in North America, is a chronic inflammatory disorder of the airways that causes wheezing and difficulty breathing
  • 2.5 million people in Canada are affected by asthma, where 12% of children and 8% of adults are affected
  • Asthma in Canadian children has jumped fourfold over the past 20 years
  • Partially because of air pollution 1 in 5 boys and 1 in 6 girls develop asthma in Canada
  • In 2005 the Ontario environment ministry cited Sarnia as having the highest levels of ozone and fine particular matter in Ontario, where the largest number of days in which the concentrations exceeded 30mg/m3 were recorded.