This document presents a study that aims to determine whether the bacterial species Pseudomonas sp. or the fungal species Penicillium sp. is more effective at biodegrading soils polluted with mercury (hydrargyrum) and lead (plumbum). The study involves collecting polluted soil samples and incubating them with the different microorganisms. Periodic tests will analyze degradation levels using atomic absorption spectrophotometry. The species with the lowest remaining metal levels after incubation will be determined the most effective bioremediation agent. The results could help develop cost-effective bioremediation methods to clean heavy metal pollution from soils.

1. Cristina M. Rivera Quiles
RISE Program

2. Problem
 Which microbial species under study (Pseudomonas
sp. or Penicillium sp.) will present higher biodegrading
potential in soils polluted with plumbum and
hydrargyrum?

3. Hypothesis
 The bacterial species Pseudomonas sp. will present
higher biodegrading activity of hydrargyrum and
plumbum.

4. Background
 Hydrargyrum and plumbum are both highly toxic heavy metals.
 In the past plumbum was found in many places and up to today it can still be
found in bullets, batteries, building construction.
 Mercury was known to be a part of thermometers, float valves, fluorescent
lamps.
 Some of the effects of the presence of these heavy metals in soil are:
 Agriculturally inefficient soils
 Acquirement of lethal diseases by exposure to polluted enviroments.

5.  Bioremediation can be a cost-effective, high efficiency, and
eco-friendly way to remediate polluted soil.
 Biostiumlation and bioaugmentation are ways of
bioremediation.

6.  Pseudomonas are bacteria
known for their rapid growth,
high accessibility and degrading
potential.
 Penicillium is a species of fungi
which is also know for its rapid
growth, high accessibility, and it
has also been known to degrade
toxic substances.

7. Importance
 The pertinence of this project is to find a way to
help cleanup soils that is:
 Cost-effective
 Eco-friendly
 Highly efficient
 Finding a better way to clean up polluted soil and
be able to prevent consequences like:
 Hydrargaria
 Plumbism
 Loss of clean soils
 Death and decrease of plants and animals.

10. Materials
 Plumbum polluted soil
 Hydrargyrum polluted soil
 10 beakers
 Nutrient fertilizer
 Micropipettes
 Incubator
 Petri dishes
 Pseudomonas sp. stock (in nutrient agar)
 Penicillium sp. stock (in PDA)
 Pseudomonas sp. culture (in nutrient broth)
 Penicillium sp. culture (in potato detrox broth)
 Atomic absorption spectrophotometer

11. Methodology
 A source of soil polluted with Hydrargyrum and
another source of soil but polluted with plumbum, will
be located and samples of the soil collected.
 Each of the samples will be taken to the laboratory and
an atomic absorption spectroscopy (AAS) will be done.
 After that, five samples for each contaminant will be
created.

12. Soil polluted with hydrargyrum
polluted soil polluted soil
Polluted soil
(Control)
x2x2 x1
Pseudomonas sp.
Nutrient fertilizer
Penicillium sp.
Nutrient fertilizer

13. Soil polluted with plumbum
Pseudomonas sp.
polluted soil
Polluted soil
(Control)
x2 x2 x1
Nutrient fertilizer
polluted soil
Penicillium sp.
Nutrient fertilizer

14. Methodology
 The beakers will be incubated at 30°C.
 Weekly qualitative and quantitative reports will be
done and analyzed, including color change, gas
presence, pH levels and humidity.
 After a period of approximately 3 months (more or
less) the samples will be studied using the Atomic
absorption spectrophotometer.

15. Data Analysis
 The results of the AAS will be compared to those in the
beginning of the experiment, and to those in the
controls.
 The simulator with the lowest presence of metals in
each ecosystem will determine which microorganism
is best for the degradation of each pollutant.

16. Possible Setbacks
 Factors that affect the success and rate of microbial
degradation are:
 nutrient availability
 moisture content
 pH
 The quality of the sampling area.

17. Future Studies
 My projections are to develop a prototype of heavy
metal degrading microorganism culture as inoculums
into quadrants on a larger scale in order to obtain the
bioremediation.
 Also, design a cost effective and sustainable
biodegradation method to improve the environmental
quality of soils.
 And continue to work with other microorganisms and
try to increase their potential as an agent of
bioremediation.

18. Refrences
 Olmsted, D., & Pearson, C. (2013, June 18). Mercury and Autism: Together
Again (Pollution Study) - AGE OF AUTISM. Retrieved from
http://www.ageofautism.com/2013/06/mercury-and-autism-together-again-
pollution-study.html
 Winsor, Van Rossum, Lo, Khaira, Whiteside, Hancock, & Brinkman. (2011).
Pseudomonas Genome Database: Improved comparative analysis and
population genomics capability for Pseudomonas genomes. Retrieved June 18,
2015, from http://www.pseudomonas.com/
 Groundwater Forum. (n.d.). Groundwater. Retrieved from
http://www.euwfd.com/html/groundwater.html
 Lead Poisoning. (2015, June 11). Retrieved from
https://en.wikipedia.org/?title=Lead_poisoning
 Mercury Poisoning. (2015, June 18). Retrieved from
https://en.wikipedia.org/wiki/Mercury_poisoning
 Schroeder, L., Tempesta, E., & Andreacchi, S. (2013, March 14). Ritualistic use of
mercury remains a mystery-but health effects aren't. Retrieved from
http://newsarchive.medill.northwestern.edu/chicago/news-219201.html

19. References
 Gadd, G., & Griffiths, A. (1978). Microorganisms and heavy metal toxicity.
Retrieved from http://link.springer.com/article/10.1007/BF02013274
 Gadd, G., & Griffiths, A. (1978). Microorganisms and heavy metal toxicity.
Retrieved from http://link.springer.com/article/10.1007/BF02013274
 Rajendran, P., Muthkrishnan, J., & Gunasekaran, P. (2003, September 1).
Microbes in heavy metal remediation. Retrieved from
http://nopr.niscair.res.in/bitstream/123456789/17153/1/IJEB 41(9) 935-944.pdf
 Rashad, M. (2007, October 17). Bioremediation of heavy metals in soil. Retrieved
from
http://www.academia.edu/3424375/Bioremediation_of_heavy_metals_in_soil
 Leitão, A. (2009, April 9). Potential of Penicillium Species in the Bioremediation
Field. Retrieved from
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2681198/#b17-ijerph-06-01393
 Donlon, D., & Bauder, J. (n.d.). Bioremediation of Contaminated Soil. Retrieved
from http://waterquality.montana.edu/docs/methane/Donlan.shtml