Focus Question:  What are the sources of pollution in the ocean?

Readings: Ch. 18, pgs.505-523,  (Ch. 18, pgs.  437-452).

This is a text version of the notes presented in class

Feel free to email the instructor (knamjesn@kent.edu) with any
comments about the format and ease of use of these online notes.

I. What is Pollution?
Substances that cause damage by interfering with an organism's physical or biochemical processes
Natural pollutants:
- example: volcanic eruptions (e.g., sulphuric acid)

"Anthropogenic" pollutants:
- introduced by human activity
- example: synthetic organic chemicals (e.g., pesticides)
 

2. Types of Marine Pollution
- Oil*
- Synthetic Organic Chemicals*
- Heavy Metals*
- Solid Waste
- Sewage
- Fertilizer
  

3. Sources and Characterization of Marine Pollution
Quantity:
 Amount of a particular pollutant present
Toxicity:
 Amount of a pollutant required to cause damage
Persistence:
 Length of time a pollutant lasts in an environment
Graphic: Garrison, Fig. 18.2, pg. 507 (Fig. 18.1, pg 439).

4. The Fate of Pollutants
Solubility = the ability of a substance to be dissolved
Common types             Characteristics               Example
  of solubility
water soluble        dissolves easily in water         liquid sewage effluent

fat soluble            binds with fat, accumulates      DDT, PCBs, some
                                   in fatty tissues                   heavy metals

insoluble                     doesn't dissolve                     oil, plastic  

The fate of a pollutant depends on its solubility

5. Sources of Oil Pollution
90% of oil enters the ocean via human activities
Graphic: Garrison, Table 18.1, pg. 508 (Fig. 18.2, pg 439).

6. Types of Oil Spills
Crude oil spills:
- large volume
- most common type of spill
- crude does not dissolve easily
Refined oil spills:
- smaller volume
- less common
- more disruptive for longer
   periods of time
- a growing concern, as more
   refined oil is transported by sea

7. What Happens to Spilled Oil?
Natural Processes:
 Evaporation
 Bacterial degradation
 Formation of tar balls,
  which sink
Cleanup Efforts:
 Recovery
 Burning
 Dispersal
Graphic: Garrison, Fig. 18.5, pg. 510, (Fig. 18.6, pg 442).

8. Consequences of Oil  Spills
Ecological impact depends on:
- Location of spill
- Distance to shore
- Water temperature
- Currents, weather
- Composition of affected marine communities
- Amount and type of oil

9. Synthetic Organic Chemicals
Sources:
- pesticides (e.g., DDT)
- flame retardants
- industrial solvents
- cleaning fluids
- coolants (e.g., PCBs)
Toxicity:
- Ingestion of small amounts can cause illness or death
- Specific warnings for children and women of childbearing age
- Immunosuppressants
 

10. Biological Amplification
Levels of synthetic organic chemicals in seawater are usually low
Effects can be amplified through the food chain as toxins accumulate in higher amounts in larger organisms
Graphic: Garrison, Fig. 18.8, pg. 512, (Fig. 18.9, pg 445).

Rachel Carson, oceanographer and author of famous book Silent Spring, documented this in the 1960’s with the example of  bioamplification of DDT, single handedly brought about major legislation that led ultimately to the Clean Water and Clean Air Acts, and the banning of insecticide DDT in the U.S.  DDT is still used in many countries throughout the world..

11. Heavy Metals - Too Much of a Good Thing
Low concentrations:
   Many heavy metals are essential nutrients
Example: iron needed for producing red blood cells
Higher concentrations:
   Can cause neurological damage, birth defects and death
Example: mercury poisoning
Graphic:  Large marlin on the swim step of a charter vessel.  R.Gaffney, photographer, courtesy of NOAA.

12. Heavy Metals
Some noxious heavy metals:
- Lead
- Mercury
- Copper
- Tributyl tin
Sources:
- Coal combustion
- Electric utilities
- Steel and iron manufacturing
- Fuel oils
- Fuel additives
- Incineration of urban refuse
- Wastewater

13. Cleaning Up Heavy Metals
Example:
   Heavy metal concentrations in tissues of marine organisms drops due to changes in wastewater treatment
Graphic:  Copper in the tissues of clams in San Francisco Bay are lower following changes in wastewater
  treatment.

14. Raw Sewage
Human and animal waste can and does enter rivers and groundwater, and discharges to the ocean through estuaries.
1. Outdated and leaking septic tanks
2. farm waste run-off
3. In some countries, poor or no waste treatment facilities-waste goes directly into harbors, estuaries
4. outcome of this-deadly diseases, such as cholera outbreaks occur

15. Fertilizer run-off-a Thanksgiving Dinner every day for algae

Lawn and farm fertilizers contain nitrates and phosphates, 2 important nutrients for plants, including algae.
 Marine algae (phytoplankton especially) take up these nutrients, and large algal blooms occur.
 In harbors and estuaries, algal scums occur, blocking light to lower water depths,
Causing an oxygen shortage at depth as decaying algae is oxidized in the water
 In the open ocean, large algal blooms affect the food chain
 Lethal or debilitating diseases can be triggered, as with Red Tide Illness from Dinoflagellate algae.  In large populations, these algae produce lethal or debilitating poisons that are taken up and concentrated in shellfish by their filterfeeding activity.  These in turn are consumed by humans, with devastating effects.

16.  Solid Waste
 Plastics, metals, general trash is often dumped at sea, with terrible consequences for organisms living in the ocean.  These objects do not dissolve, and breakdown so slowly (over centuries) that they become permanent parts of the ocean floor landscape.
Plastics-a growing problem-small plastic parts choke animals, 6-pack plastic rings trap and eventually choke animals,
Metal objects rust and break down, often releasing heavy metals into the water column (car batteries, hot water heaters, metal scrap).

17.  Coasts are very likely places for pollution to occur, and yet they are also very sensitive ecosystems.  This combination makes pollution impacts more severe. With increasing population pressure along coasts, better ideas to improve conditions and better ways of implementing those ideas are necessary.

Next lecture:  Estuaries and Coastal Marine Communities
Focus Question:  Why are estuaries so productive? 

Readings: Ch. 12, pgs 336-339 and Ch. 16, pgs. 447-455, (Ch. 12, pgs 295-297 and Ch. 16, pgs. 390-402).