1. Exam IV Exam IV will be offered on Wed. Dec. 5 in class
It will also be offered during the regularly scheduled time
Thursday, December 13th
Study Guide will be posted this afternoon

2. A toxic neighbor 90-acre site
contaminated with a mix of wood-treating chemicals
90-acre site
Gainesville Sun – November, 30th
Tests show arsenic and dioxins in the soil at levels exceeding state cleanup standards.
Dioxin ½ life in soils: 10 – 30 years

3. Organic Chemicals

4. Dioxin PCB DDT Principally carbon, hydrogen 0.2 µg/L 10-31 µg/L
(50% Cl)
DDT
insoluble
.2 ug/L = .5g in an olympic sized swimming pool (2,500,000 L)
Principally carbon, hydrogen

5. Improving Solubility Organic Solvents Soap/detergents
Hexane
Structural similarity between
the chemical and the solvent.

6. Lipids and Solubility Structural similarity between
the chemical and the solvent.

7. Solubility A chemical’s solubility in lipids or organic solvents
is inversely proportional to its solubility in water.
(Carbon/hydrogen)
Carbon/hydrogen
water

8. Consequences
Concentration of a chemical up the food chain.

9. Bio-Accumulation Overall: 120,000 times original concentration
Water and phytoplankton to zooplankton: 800 x
Zooplankton to fish: 31 x
Fish to eagle: 4.8x
water to zooplankton: 800x  zooplankton  to fish #1: 31x  fish #1  to fish #2: 1.7x  fish #2 to  gull: 4.8x  overall:  202,368x
Overall: 120,000 times original concentration

10. PCBs
Spokane
River
Nov. 2002
lake trout contained PCBs above the 2000 ng/g level. In fact, 56% of lake trout samples exceeded this tolerance level
Carp
72.8
3400-
7300
8/17/00 9-BST Bluestone
River at Rt.
643 Falls
Mills
White
Sucker
43.8
468-
1034
Rock
Bass
Redbreas
t Sunfish
18.1
8/17/00 9-BST Bluestone
460
Bluefield
Stone
Roller
17.5
33.9
238-
304
Smallmouth bass ppb    Round gobies ppb    Zebra mussels ppb

11. Toxaphene Biomagnification
Seawater
ppb
Arctic cod muscle
ppb
Toxaphene is a manufactured insecticide that contains over 670 Chemicals (ATSDR, 2001).Toxaphene, one of the heaviest used insecticides in the U.S., has been used to control insect pests on crops and livestock and to kill unwanted fish in lakes (ATSDR, 2001). Cumulative world use from 1946 to 1974 was more than 409,000 metric tons (O'Shea, 1999). The United States ceased using toxaphene in 1982, but it is still used in many other countries (O'Shea, 1999). For example, the Virgin Islands and Puerto Rico use it in banana and pineapple cultivation (Burland).Once Toxaphene is added to the environment by human action, it can then enter the air, water and soil. It can enter the air by evaporation, the water through runoff, and the soil by sticking to soil particles (ATSDR, 2001). The most likely route of entry for toxaphene into the environment is evaporation from soils (GPA). Although toxaphene can be in water, it does not dissolve well so it is more likely to be found in air, soil, or sediments underwater (ATSDR, 2001). Once the toxaphene is introduced into the environment it remains there for a long time due to its very slow break down time (ATSDR, 2001). Toxaphene has a half-life as long as twelve years once in the soil (GPA).Toxaphene can be spread through the environment by atmospheric transport and is found in low concentrations in tissues of marine mammals in remote areas were it has never been used, such as the artic (O'Shea, 1999).
Narwhal
blubber
ppb

12. Non-point source Biomagnified Other Hydrocarbons Chlordane Mirex DDT
1983
1972
Chlordane
Mirex
DDT
Dieldrin
Chlordane
DDT
Urban Runoff Pet wastes, yard debris, paints, vehicle emissions, used or unwanted motor vehicle fluids, car-washing residues, oil and grease from driveways, litter, fertilizers, pesticides and household hazardous chemicals are some urban pollutants that can be carried by water running over land and paved surfaces. This water can flow into storm drains and reach local waterbodies, without being treated in any way.
Onsite Sewage Systems Onsite sewage systems which are not properly maintained can cause drainfields to become plugged and cause partially treated wastewater to surface on your lawn and/or flow to nearby waterbodies. Wastewater from improperly constructed or located sewage systems can also pollute ground water.
Agriculture Fertilizers, herbicides, pesticides, along with parasites and bacteria from livestock waste, can run off farmland and pollute surface water or seep into the ground and pollute ground water. Livestock movement near and in streams can erode stream banks and destroy fish habitat.
Boating Sewage, garbage, dishwater, cleaning and refinishing products and fuel leaks from boats can all damage water quality.
Non-point source
Biomagnified

13. Mirex highest levels ever recorded in a living organism.
The influence of pollutants such as PCBs, DDT, mirex, and toxaphene is assessed in a population of 500 beluga whales residing in the St. Lawrence River system. This population suffered a dramatic decrease in numbers at the turn of the century, and population numbers continue to slowly decrease. Reasons for this continual decline including biomagnification factors and bioaccummulation are considered. Because they occupy a high level on the food chain, beluga whales accumulate larger quantities of pollutants. Due to the transferance of pollutants through lactation, calves, younger females, and males have higher concentrations than older females. Some of the effects of the pollution are compromised immune systems, reproductive problems, and increased death rates. Pollution is so concentrated in some beluga whale carcasses that they are treated as hazardous waste.
Even though belugas have been protected from hunting since the 1970s, their numbers have failed to rebound. Chemical analyses of their blubber have detected PCBs, DDT, chlordane and toxaphene - at some of the highest levels ever recorded in a living organism.
highest levels ever recorded in a living organism.

14. Quantification
How can soils help?

15. An Important Organic Solvent: Octanol
C8H18O

16. The Octanol-Water Partitioning coefficient
C8H18O
Octanol and water are immiscible
Density: g/cm3
octanol
C8H18O
water

17. Partitioning
Carbon/hydrogen
Octanol (Carbon/Hydrogen)
water
C10H20

18. Add 10 mg chemical
1 L Octanol
1L Water
separate
chemical
Analyze the water phase for the chemical.
Difference between initial amount and amount in water = amount in octanol
The ratio between the two yields the Kow

19. Kow = Add 10 mg chemical 1 L Octanol 1L Waterl separate chemical
= 999
0.01 mg L
Water phase
octanol phase

20. Kow of some Organochlorine Compounds
Dioxin 6,000,000
PCBs 2,000,000
DDT ,000,000
Dieldrin ,000
Toxaphene 316,000

21. What does this have to do with soils?

22. Organic Matter Carbon Hydrogen Oxygen
Coiled and convoluted chains of carbon, hydrogen, and oxygen

23. Organic Matter
COOH OH
carboxylic
enolic C H C
Carbon
Hydrogen
Oxygen

24. Partitioning/Distribution
Organic matter
Soil Solution
Absorption

25. Turn 4 pages

26. Quantifying Partitioning and Absorption in Soils

27. Quantifying Absorption
1 g Soil added
(10% O.M.)
75 mg/L
Equilibrium
1 Liter
100 mg/L
25 mg/g
Pesticide
solution

28. Distribution Coefficient
(mg/g soil)
(mg/L solution)
Pesticide on soil
Pesticide in solution
Kd =
75 mg/L
Equilibrium
25 mg/g
Kd =
25 mg/g
75 mg/L
= 0.3 L/g
= 300 mL/g
Index for a given soil

29. Two Soils Same Pesticide 75 mg/L 40 mg/L 25 mg/g 60 mg/g
Kd (2) = 60 mg/g
40 mg/L
Kd (1) = 25 mg/g
75 mg/L
Kd (2) = 1.5 L/g
Kd (1) = 0.3 L/g
= 1500 mL/g
= 300 mL/g

30. Organic Matter and Organic Carbon
Retention of organic chemicals is strongly correlated with O.C. content
Organic matter = % carbon
approximately
50% organic carbon

31. Organic Carbon Distribution CoefficientKd
Koc=
Fraction o.c.
75 mg/L
25 mg/g
Kd (1) = 3 L/g
10% o.c.
Koc (1) = 0.3 = 3 L/g
0.1
40 mg/L
60 mg/g
Kd (2) = 1.5 L/g
50% o.c.
Koc (2) = 1.5 = 3 L/g
0.5
= 3000 mL/g
= 3000 mL/g

32. Koc of some Organochlorine Compounds
PCBs 2,000,000
DDT ,000,000
Dieldrin ,000
Toxaphene 316,000

33. Modern Pesticides Atrazine Solubility = 30 mg/L Carbaryl
napthalene
Solubility = 32 mg/L C C C C

34. Koc = 2 – 6000 mL/g Dicamba = 2 Malathion = 1800 Chlorpyrophos = 6070
Practical Range for Some Modern Pesticides
Koc = 2 – 6000 mL/g
Dicamba = 2
Malathion = 1800
Chlorpyrophos = 6070

36. Summary Many organic compound are non-polar
Non-polar compounds are weakly soluble in water
Non-polar compounds are soluble in organic solvents.
Organic matter can behave like an organic solvent
Kow describes the distribution of a chemical between
the organic solvent, octanol, and the soil solution.
Koc describes the distribution of a chemical between
soil organic carbon and the soil solution.
Koc will impact the movement and distribution of
organic chemicals in soils.
Organic chemicals degrade. The ½ life is an indicator of
the chemicals relative persistence.