Window Cleaners Effects on Euglena
Algae
John Wearden
Grade 9
Central Catholic High School
Window Cleaners
Include any chemical used as a cleaning product intended
for use on a surface
May include chemicals that are potentially toxic
May runoff and harm organisms
Long term effects, unclear
Eutrophication
Caused by an overabundance of nutrients in an ecosystem
No limiting factor on algae populations
Uncontrollable growth takes up resources for other
organisms-oxygen
Limits biodiversity
Can occur naturally
Windex
Active Ingredients
2-Hexoxethanol Chemical Formula C8H18O2, coalescing agent, can cause
depression and kidney failure, severe irritant
Ammonium Hydroxide Chemical Formula NH4OH Can cause breathing
complications if inhaled
Giant Eagle Window Cleaner
Active Ingredients
Ammonia NH3, if inhaled can lead to lung damage and death
Glycol Ether Can cause severe liver and kidney damage, as well as fatigue,
lethargy, and anorexia with chronic exposure.
Green Shield
Active Ingredients
Acetic Acid - CH3COOH, mild irritant
Algae
Large diverse group of simple, and usually autotrophic organisms
Basis of the aquatic food chain
Used as as a bio-indicator for aquatic environments
Euglena gracilis
Algal - like protist
Survives in both fresh and salt water
Performs photosynthesis and endocytosis
Becomes dormant in negative conditions
No cell wall
Common experimental model
Chlamydomonas reinhardtii
Flagellated, unicellular green algae
Commonly found in fresh water
Generally light sensitive
Common experimental model
No cell wall
Purpose
To determine the effects various window cleaners have on algae
To examine the effects of window cleaners on algal population density
Hypothesis
Null Hypothesis: The window cleaners will not significantly affect algal or
survivorship
Alternative Hypothesis: The window cleaners will significantly affect algal
survivorship
Materials
micro pipette (1000µL)
tips for micro pipette
30 test tubes (borosilicate 13x100mm)
4 tube racks
45 mL euglena gracilis
45 mL chlamydomonas reinhardtii
84 mL spring water
90 mL of soil water
7 mL Windex window cleaner
7 mL Giant Eagle window cleaner
7 mL Green Shield window cleaner
Carolina spectrophotometer
wax paper
large window
Procedure
1.
2.
Created a stock solution of 10% and 1% for each window cleaner.
Window cleaners, algae, spring water, and soil water were used to create the following solutions.
1% .1% .01% .001% and 0%.
Solution Table
0
.001
.01
.1
1
Algae
1
1
1
1
1
Variable
0
.05
.5
.05
.5
Spring
Water
3
2.95
2.5
2.95
2.5
Soil Water
1
1
1
1
1
Procedure (continued)
3. Tubes were placed in racks recieving equal sunlight from the same window.
4. Every other day absorbance reading were taken using a spectrophotometer set at 430nm.
Statistical Analysis
ANOVA
Compares variation within groups to variation between groups.
If a p-value is less than the alpha .05 it suggests that the null
hypothesis can be rejected.
Dunnett’s Test
Compares each experimental group to the control group
individually
Each experimental group is then compared to t-crit value of 3.5
Day 6: P-value .002
Day 14: P-value .003
above alpha .05
Day 6: P-value .0001
Day 14: P-value .018
above alpha .05
Day 6: P-value .006
Day 14: P-value .173
above alpha .05
Day 6: P-value .568
Day 14: P-value .003
above alpha .05
Day 6: P-value: .004
Day 14: P-value: .006
above alpha .05
Day 6: P-value .544
Day 14: P-value .868
Dunnett’s Test
Euglena
Windex
Euglena
Giant Eagle
Euglena
Green
Shield
Chlamydom
onas
Windex
Chlamydom
onas
Giant Eagle
Chlamydom
onas
GreenShiel
d
Day 6
4.37285 sig
3.49276 sig
2.60912
(did not
have an
alpha of .05)
3.38217 sig
(did not
have an
alpha of .05)
Day 14
5.67261 sig
3.28561 sig
(did not
have an
alpha of .05)
4.30152 sig
3.26012 sig
(did not
have an
alpha of .05)
Alpha: 3.05
Conclusion
Accept the alternative hypothesis for the Windex cleaner and Giant Eagle cleaner.
All were determined as having significant long term effects.
Reject the alternative hypothesis for the Green Shield cleaner
None were determined to have significant long term effects
Limitations and Extensions
Limitations
The growing period occurred during the middle of December, different
effects may rise with more sunlight
Extensions
Further chemicals can be isolated to determine which causes the effect
or which combination causes the effect.
More diverse species could have been used to better model an
ecosystem
More replicates could be used to nullify any outliers
References
http://www.epa.gov/
http://www.windex.com/
http://www.gianteagle.com/
http://www.ewg.org/
http://www.britannica.com/
http://www.nlm.nih.gov/