health health: a state of complete physical, mental and social well-being, not merely the absence of...
Post on 22-Dec-2015
215 Views
Preview:
TRANSCRIPT
HealthHealth: a state of complete physical, mental and social well-being, not merely the absence of disease or infirmity.
•Therefore, we are all ill to some extent
•We can also all improve our health to live happier, longer , more productive lives
Disease
• Disease: a deleterious change in the body’s condition in response to an environmental factor
– Types• Nutritional• Chemical• Biological• Psychological
Infectious Organisms
• Pathogens, disease causing organisms– kill 18 million people/year worldwide
• Different kinds– Respiratory infections: Pneumonia and influenza– Perinatal conditions including surrounding birth take
2.4 million lives/year– 2 Billion cases of diarrhea/ year lead to 2 million
deaths– AIDS Virus
• 30 million now affected, 2.9 million die each year
Emergent Diseases and Environmental Change
• Emergent disease is one that one never knew of before or has been absent for at least 20 years. – Ex: Ebola fever; – Causes
Causes of Emergent Diseases
• Travelers bring new germs to a naïve population
• Human densities are very high
• Expanding populations push into remote areas
• We are changing our environment– Elimination of predators favors disease carrying
organisms such as mice, rats and mosquitoes.
Antibiotic and Pesticide Resistance
• Careless application by humans– Over use of insecticides
• Pathogens evolve rapidly – Lead to resistant pathogens
• Malaria was greatly reduced throughout the world, but now it’s back
Environmental Toxicology
• Environmental Toxicology– Deals with toxicants that come from or are
discharged into the environment– On they affect humans, other animals and the
ecosystem– Animals can be ‘canaries in a coal mine’
Toxic Chemicals
• Hazardous- dangerous– Includes flammables, explosives, irritants,
sensitizers, acids and caustics
• Toxicant- poison to human or wildlife– React with specific cellular components to
kill cells
• Allergens: substances that activate the immune system.
Carcinogens
• Carcinogens- substances that cause cancer, invasive out-of-control cell growth
– A.C.S. : ½ of males and 1/3 of females will have some form of cancer in their lifetime.
Fun at the Beach
Current State of Our Orcas
Highline Community College
Dead Orcas
State of Southern Resident Orcas
• Almost 20% orcas died between 1995 and 2000.
• Reproductive females have not produced young in ten years.
• Only four adult males in the entire community of 80 whales.
Killer Whales- Orcas
• Orcinus orca
• Largest member of the dolphin family, Delphinidae
• Identifying traits– Tall dorsal fin– Saddle patch behind dorsal fin– White patches on sides, belly and behind eyes
Orca Biology
• Average Birth Weight: 395 lbs
• Average Adult Weight: 2.6 – 9 tons– Males are larger than females
• Lifespan:– Males ~40 years– Females >60 years
• Sexually mature ~13 years
Orca Natural History
• Found in all the world’s oceans
• Travel in pods from 3 to >150 members
• Feed on fish, squid and marine mammals
Transient vs. Resident Orcas
Transients Residents
Habitat Offshore Nearshore
Food Marine Mammals
Fish
Pod Size 3-5 >20
Vocalization Quiet Very Vocal
Resident Orcas
• Resident orcas live in coastal areas feeding mostly on fish
• Live in extended familial units called pods– Pods are matriarchal
• Northeast Pacific resident orcas are found from Puget Sound to Alaska– Puget Sound orcas are Southern Resident
Orcas
Southern Resident Orcas
• Consists of three pods: J, K and L
• Summer in the area around the San Juan Islands feeding on salmon runs
• Winter on outer coast, but do not know where
Puget Sound Orcas and PCBs
• Highest levels of PCBs in blubber of any marine mammal in the world– Average almost 150 ppm– <10 ppm PCB is known to cause immune
problems in seals
• Dead female transient orca on Dungeness Spit in May 2002 – 1000 ppm PCB– 12ppm- EPA’s standard for marine sediments
Polychlorinated Biphenyls(PCBs)
Cl
Cl
Cl
Cl
PCBs
• Highly stable oily fluids and solids– Transformers, pesticides, etc
• Fat soluble – Reside in fatty tissue
• Block hormone activity– Destroy normal immune function– Cause liver cancer, pituitary tumors, leukemia, and
lymphoma
• Banned in U.S. since 1977
Ecosystem Review
• Ecosystem– Organisms interacting with environment
and each other through a food chain
• Food Chain – Biomass moves from one organism to
another as each eats a lower member and, in turn, is eaten by a higher member
Generalized Ecological Pyramid
2° Consumers3° Cons.
1000 g Biomass
100 g
10 g
1 g
Primary ProducersPrimary Consumers
Idealized Puget Sound Ecological Pyramid
1000 g
100 g
10 g
1 g
PhytoplanktonZooplanktonSalmon
Orcas
Pollutants
• Pollutant–Adversely affects the health, survival,
or activities of living organisms
–Persistent Organic Pollutant• POP• Stable, Long Lasting• Includes DDT and PCBs
Sources of Pollutants in the Environment
• Point Source–Specific location of concentrated
pollutants• Factory Waste, Sewage
• Nonpoint Source–Scattered or diffuse sources of
pollutants • Golf Courses, Agriculture
Factors Influencing Impact of Pollutants
• Solubility– Water soluble pollutants
• Move easily through environment
– Fat soluble pollutants• Need a carrier • Long-lasting in body’s fatty tissue
• Persistence– More stable– Longer to break down– More harm it can do
Pollutants in the Food Chain
• Bioaccumulation– Cells increase the concentrations of
molecules relative to the environment
• Biomagnification– Concentration of pollutants increases as
they move up the ecological pyramid– Only 10% of biomass, but most of the
pollutant is transferred
DDT in a Long Island Estuary(from Woodwell, Wurster and
Isaccson, 1967)
Trophic level Organism DDT in wet weight of whole organism
Primary Producer
Green Alga 0.08 ppm
Primary Consumer
Mud Snail 0.26 ppm
Secondary Consumer
Summer Flounder
1.28 ppm
Tertiary Consumer
Ring-billed Gull
75.5 ppm (1000x initial concentration)
Idealized Puget Sound Pyramid
With PCBs
1000 g
100 g
10 g
1g
PhytoplanktonZooplanktonSalmon
Orcas
1 g
Trophic Level %PCBPhytoplankton 0.1%Zooplankton 1%Salmon 10%Orcas 100%
The ‘Double Whammy’• In blubber, PCBs are not very harmful.
• Low salmon runs force orcas to metabolize more blubber to survive.
• The blubber releases PCBs into the blood, destroying the immune system.
• Therefore, starvation increases the lethality of the pollutant.
top related