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COMMON TOXIC POLLUTANTS

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Title: COMMON TOXIC POLLUTANTS


1
COMMON TOXICPOLLUTANTS
2
I. BIOCIDES
  • SOURCES
  • Pesticides
  • Insecticides
  • Herbicides
  • EFFECTS
  • Carcinogenic meaning??
  • Nerve damage
  • Liver damage

3
I. BIOCIDES
  • EXAMPLES
  • Dioxins ingredient in insecticides
  • Used by paper mills in bleaching process
  • Used in PVC plastics
  • An ingredient in agent orange
  • Agent Orange herbicide
  • Widely used in Vietnam as a defoliant
  • Caused cancer, birth defects, sterility

4
I. BIOCIDES
  • EXAMPLES
  • 24D common herbicide
  • Causes lymphoma (cancer) in dogs
  • DDT insecticide
  • Caused egg shell thinning
  • Blamed for the near extinction of eagles, falcons
    and pelicans

5
DDT (dichlorodiphenyltrichlorethane)
  • Insecticide used very effectively against
    mosquitoes, which cause malaria
  • Builds up in plants and fatty tissue in fish,
    birds and other animals
  • Banned in the US in 1972
  • Still used in other countries

6
BIOMAGNIFICATION
  • A chemical becomes concentrated as it passes
    through a food chain

7
DDT
  • The concentration effect occurs because DDT is
    metabolized and excreted much more slowly than
    the nutrients that are passed from one trophic
    level to the next. So DDT accumulates in the body
    (especially in fat).

8
DDT
  • This is why the hazard of DDT to nontarget
    animals is particularly acute for those species
    living at the top of food chains.

9
DDT A Threat to Americas Bald Eagles
10
II. FOSSIL FUELS (coal, oil gas)
  • SOURCES
  • NO2 H2O ? HNO3
  • (process occurs when burning gas)
  • SO2 H2O ? H2SO4
  • (process occurs when burning coal)

11
II. FOSSIL FUELS (coal, oil gas)
  • EFFECTS
  • Respiratory problems
  • Sterile lakes
  • Kills forests
  • Damage to monuments, cars, buildings
  • Global warming
  • Acid rain

12
II. FOSSIL FUELS (coal, oil gas)
  • SOLUTIONS
  • Burn higher grade fuels
  • Scrubbers
  • Others??

13
III. Hg (mercury)
  • SOURCES
  • Paper mills to treat logs
  • Agriculture to treat seeds
  • Occurs naturally in mines
  • Acid rain releases it naturally from sedimentary
    rock
  • Latex paint

14
III. Hg (mercury)
  • EFFECTS
  • Mercury exposure at high levels can harm the
    brain, heart, kidneys, lungs, and immune system
    of people of all ages.
  • high levels of mercury in the bloodstream of
    unborn babies and young children may harm the
    developing nervous system, making the child less
    able to think and learn

15
III. Hg (mercury)
  • Our inland fish are unsafe to eat due to high
    levels of Hg
  • Hg cannot be eliminated from the body in any way
  • Found in muscle tissue

16
IV. Pb (lead)
  • SOURCES
  • Water pipes
  • Gasoline
  • Paints
  • Batteries
  • Ceramic pottery
  • Soldering

17
IV. Pb (lead)
  • EFFECTS
  • Hyperactivity
  • Paralysis
  • Brain damage
  • Birth defects
  • High BP

18
IV. Pb (lead)
  • 4 of preschool children have below normal IQ
  • 20 of Americans drink too much H2O containing Pb
  • 2 million waterfowl each year die of lead
    poisoning

19
V. PCB (Polychlorinated Biphenyls)
  • SOURCES
  • Insulators for electrical transformers
  • Sealants for wood and cement
  • Hydraulic fluids
  • Paper mills for carbon paper
  • pigments, dyes
  • as plasticizers in paints, plastics and rubber
    products

20
V. PCB (Polychlorinated Biphenyls)
  • EFFECTS
  • Carcinogen
  • including effects on the immune system,
    reproductive system, endocrine system and nervous
    system

21
V. PCBContaminating the Hudson River
22
V. PCB (Polychlorinated Biphenyls)
  • Polychlorinated biphenyls (PCBs) are a family of
    209 chemical compounds for which there are no
    known natural sources.
  • Even though PCBs are no longer commercially
    produced in the United States, high levels of the
    chemicals remain in various parts of the country,
    in poultry, and in fish.

23
V. PCB (Polychlorinated Biphenyls)
  • The very characteristic of the PCBs that made
    them wonderful for use in manufacturing makes
    them problematic in the environment. PCBs are
    very persistent they are generally unalterable
    by microorganisms or by chemical reaction, so
    they do not readily degrade.
  • The stable nature of PCBs also lends to
    accumulation in the fatty tissues of animals once
    the PCBs are released into the environment. These
    accumulations increase as the tissue from
    contaminated animals moves through the food web.
    Because of _________, the concentration of PCBs
    found in fish tissues is expected to be
    considerably higher that the average
    concentration of PCBs in the water from which the
    fish were taken.

24
VI. CFC (chlorofluorocarbon)
  • SOURCES
  • aerosol-spray propellants
  • refrigerants
  • Solvents
  • Styrofoam (pre, CFC-free styrofoam)
  • foam-blowing agents
  • They are well-suited for these applications
    because they are nontoxic and nonflammable and
    can be readily converted from a liquid to a gas
    and vice versa.

25
VI. CFC (chlorofluorocarbon)
  • EFFECTS
  • Destruction of the ozone layer which protects us
    from ???
  • UV rays from the sun
  • How does this happen?

26
VI. CFC (chlorofluorocarbon)
27
VII. PBB (Polybrominated Biphenyls)
  • SOURCES
  • PBBs are manufactured chemicals
  • They are added to the plastics used to make
    products like computer monitors, televisions,
    textiles, plastic foams, etc. to make them
    difficult to burn. PBBs can leave these plastics
    and find their way into the environment.
  • EFFECTS
  • Carcinogen
  • More will be observed in the movie
  • Bitter Harvest

28
VII. PBB (Polybrominated Biphenyls)
  • Exposure to PBBs is most likely to occur by
    ingesting contaminated foods and drinks.
  • People living in the lower peninsula of Michigan,
    where animal feed was accidentally contaminated
    with PBBs in 1973, may still be exposed by eating
    contaminated fish, dairy products, and meat.
  • If you don't live in Michigan, exposure to PBBs
    is likely to be very low.
  • You can be exposed to PBBs in the air if you live
    near a waste site that contains PBBs.

29
  • The movie Bitter Harvest
  • PBB contamination resulted in the most
    devastating disaster in agricultural history
  • In 1973 in St. Louis, MI
  • The government did not eliminate PBB from the
    food chain until 1977
  • Farmers sold cows to an area baby food company
  • Firemaster (flamestar) vs. Nutrimaster (MgO)
  • All livestock had to be killed
  • 30,000 cattle 1,470 sheep
  • 5,900 pigs 1.5 million chickens

30
VIII. NO3 and PO4 (nitrates
phosphates)
  • SOURCES
  • Soil background concentrations
  • Fertilizers agricultural residential
  • Sewage wastewater treatment plants
  • remove 90-95 of P N in
  • solids, and the sludge is then
  • land applied as fertilizer

31
VIII. NO3 and PO4 (nitrates
phosphates)
  • EFFECTS
  • Eutrophication
  • Algae blooms
  • Decreasing light and O2 levels
  • Currently in the news
  • Allegan, Ottawa, and Muskegon Counties all have
    baned the use of fertilizers containing phosphorus
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