PPM –

PPB –

PPT –

Parts per million (1 in per 1,000,000 , 10-6 )

Parts per billion (1 part in 1,000,000,000 , 10-9 )

Parts per trillion (1 in 1,000,000,000,000 , 10-12 )

1m

1m

1m

1 cube would be

considered 1 PPM

1 inch in 16 miles 1 minute in two years 1 cent in $10,000 1 ounce of salt in 31 tons of potato

chips 1 bad apple in 2,000 barrels of apples

1 inch in 16,000 miles 1 second in 32 years 1 cent in $10,000,000 1 pinch of salt in 10 tons of potato

chips 1 lob in 1,200,000 tennis matches 1 bad apple in 2,000,000 barrels of

apples

1 postage stamp in the area of the city of Dallas

1 inch in 16 million miles (more than 600 times around the earth)

1 second in 320 centuries 1 flea on 360 million elephants 1 grain of sugar in an Olympic sized pool 1 bad apple in 2 billion barrels

Pollution refers to the occurrence of unwanted change in the environment introduction of harmful or toxic materials into the

surroundings Contamination

similar to that of pollution implies making something unfit for a particular

use through the introduction of toxic materials

Physical hazards = occur naturally in our environment Earthquakes, volcanoes, fires,

floods, droughts We can’t prevent them, but

we can prepare for them We increase our vulnerability

by deforesting slopes (landslides), channelizing rivers (flooding), etc.

We can reduce risk by better environmental choices

Chemical = synthetic chemicals such as pesticides, disinfectants, pharmaceuticals Harmful natural chemicals

also exist

Biological = result from ecological interactions Viruses, bacteria, and other

pathogens Infectious (communicable,

or transmissible) disease = other species parasitize humans, fulfilling their ecological roles

We can’t avoid risk, but we can reduce the likelihood of infection

Cultural = result from the place we live, our socioeconomic status, our occupation, our behavioral choices Smoking, drug use, diet and

nutrition, crime, mode of transportation

Environmental health = assesses environmental factors that influence human health and quality of life (Natural and human-caused )

Despite our technology, disease kills most of us

Disease has a genetic and environmental basis Cancer, heart

disease, respiratory disorders

Poverty and poor hygiene can foster illnesses

Tuberculosis, acquired immunodeficiency syndrome (AIDS), and the West Nile virus

Our mobility spreads diseases

Diseases are evolving resistance to antibiotics

Climate change will expand the range of diseases

To predict and prevent diseases, experts deal with complicated interrelationships

Infectious disease Spread by interactions between

individuals and through food, water, air or soil.

Can travel globally via airplanes New diseases emerging and

previous ones reemerging Some infectious diseases can be

controlled by manipulating the environment

If you really knew me…