1. The Affect Sulfates have on Daphnia

2. Purpose: Hypothesis:
To determine if sulfates in shampoo affect biological processes
As various concentrations of SLS increase, the effect it has on Daphnia will be observed

3. Daphnia Also known as the “water flea”
Have a life span average of 30 days
(1 month)
More active in sunlight
Are transparent

4. What They Eat Can eat a variety of things:
Yeast
Bacteria
Soy flour
Algae
Dissolved organic matter
Detritus
Over-feeding will pollute the water and kill Daphnia

5. Preparing the Tank
Beware of additional chemicals- they will kill off Daphnia culture
Use distilled water only, not tap
Make sure light is indirectly on tank
Daphnia live best in water with a temperature between ˚F
It is also best to use a Bio-Foam filter to keep the water circulating and full of oxygen

6. Daphnia Reproduction
Female Daphnia can produce eggs without mating –parthenogenesis
In each hatching, there are about 50 eggs
These eggs will be held in a
blood chamber for a few days
until it is time for them to hatch

7. Sodium Lauryl Sulfate Found in shampoos, shower gels,
mouth rinses, toothpaste, car and detergents
Type of surfactant-breaks
the surface tension of water (makes
the suds bubbles)
Most shampoos contain about 30% of SLS- a very high concentration

8. Effects of SLS
Associated with causing cataracts-in concentrated amounts
Can be drying and harsh for the hair
Causes eye irritation, allergic
reactions, and hair loss
High levels of skin penetration
occur at even low concentration

9. Procedures for Testing- Part 1
Divide Daphnia into Well cups
Add a different concentration
of SLS into each set of cups-start with
the most diluted.
We had a control group, as well as groups being tested with different SLS concentrations
Leave Daphnia in solution, monitor the time
As the time in solution comes to an end, place Daphnia under microscope

10. Procedures for Testing – Part 2
Place small, thin strands of cotton on top of Daphnia, to keep them from moving
Record number of heartbeats, how many times the Daphnia move, if it has eggs, and if its alive or dead
Place Daphnia back into tank
Repeat with different concentrations

11. Serial Dilution In the 1000mL volumetric flask, place 1 mL
of SLS and fill the rest with water
Take 1 mL of that solution and place in another volumetric flask, fill the rest with water. And repeat a second time
Place Daphnia in most diluted solution and gradully increase concentration

12. Materials We Used Algae Tank (16in by 10.5in by 8.5in) Daphnia
Sodium Lauryl Sulfate- 29% concentration
Well cups
A Bio-Foam filter
Cotton Balls
Volumetric Flasks
Digital Microscope
Plastic Spoons

13. Relating to Society
By testing different concentrations of SLS on Daphnia, we were able to conclude that small diluted amounts of SLS do not harm or cause complications in pregnancy.
However, it was noticed that the majority of the Daphnia in SLS solutions, did not contain eggs.

14. Technology
The technology needed to conduct this experiment has already been invented
Though higher resolution microscopes would have made it easier to count the heartbeats and study the bodily functions of the Daphnia

15. Data Table 1 Control Group Daphnia # of Heartbeats (per min)
# of Movements (per min)
Have Eggs?
Dead or Alive? 1 85 62
Yes
Alive 2
127
116 No 3
Dead 4 89 72 5 99 84
Average
100
83.5
40%
20%

16. Pie Charts for Control Group
Mortality
Eggs Present

17. Data Table 2 .00001% SLS- 3.5 hrs Daphnia # of Heartbeats (per min)
# of Movements (per min)
Have Eggs?
Dead or Alive? 1 96
117 No
Alive 2
122 27 3 93 66 4 76 69 5 89 82
Average
95.2
72.2 0%

18. Pie Charts for % SLS
Mortality
Eggs Present

19. Data Table 3 .0001% SLS- 24 hrs Daphnia # of Heartbeats (per min)
# of Movements (per min)
Have Eggs?
Dead or Alive? 1 No
Dead 2 3 4 5
Average 0%
100%

20. Pie Charts for .0001% SLS
Mortality
Eggs Present

21. Data Table 4 .01% SLS- 10 min Daphnia # of Heartbeats (per min)
# of Movements (per min)
Have Eggs?
Dead or Alive? 1 75
105
Yes
Alive 2 79 70 No 3
Dead 4 34 42 5
Average
62.7
72.3
20%
40%

22. Pie Charts for .01% SLS
Mortality
Eggs Present

23. Data Table 5 1% SLS- 15 min Daphnia # of Heartbeats (per min)
# of Movements (per min)
Have Eggs?
Dead or Alive? 1 No
Dead 2 89 60
Alive 3 72 77 4 5 67 70
Average 76 69 0%
60%

24. Pie Charts for 1% SLS
Mortality
Eggs Present

25. Affect of SLS concentrations on Daphnia
Number of Occurrences
Concentration of Solution (%)

26. Limitations
The microscope we used allowed us to see inside the Daphnia but it would have been better if it had a higher resolution
If repeating the project, we would clean the tank more often, to prevent the Daphnia from dying due to natural causes and toxic water

27. Sources (Part 1) www.antfire.com www.caudata.org/daphnia
health-information-centre.com/sodium-lauryl-sulfate.html

28. Sources (Part 2)