Mercury In Skin Supplies
BY: ABDIHAKIM ABDULLAHI
CHEM 4101
DECEMBER 9, 2011
Background
 Mercury in bleaching and cosmetic creams were introduced in
the early 1900 when it was discovered that Mercury was
extremely effective in lightening dark spots and stubborn
pigmentation but it also had a high remission rate.
 Nevertheless bleaching creams with high levels of Mercury was
aggressively marketed to black people. In 1976 Mercury was
banned in the EU when it was discovered that it had damaging
side effects. The US banned the use of Mercury in cosmetic
creams much later in 1990.
 Mercury was banned as it proved to be very toxic and could
absorb readily through the skin causing neurological effects.
Problem:
Recently more and more products such as Diana and Lemon
Herbal Whitening Cream have shown up in the markets,
through informal trade, with mercury levels well over the
permitted federal limits, of less then one parts per million, of
mercury. Some of these products have shown levels at 33,000
parts per million of mercury.
Hypothesis:
Mercury in said products cause a lot of health issues especially
pertaining to communities in which these products keep
showing up in.
Experiment Overview
 Separation: My analyte,
inorganic mercury, is in a
very complex matrix
(cosmetic cream) so the
first thing we have to do
is separate the mercury.
 Identify: Next we have to
identify the mercury,
then quantify it.
A bottle of mercuric chloride
which was classified as a
poison.6
Possible Detector techniques
Technique
Advantages
Disadvantages
UV-Vis Absorption
Simple design, quick
sample analyses and it is
nondestructive to sample.
Requires frequent
calibration, stray light can
alter results.
Atomic Absorption
Spectroscopy
Simultaneous analyses of
different elemental
species can be done. It
can be used for trace
analysis. Fast.
A large number of
interferences are possible,
such as the formation of
non-volatile compounds,
smoke formation which
will absorb light,
contamination etc.
Fluorescence
Highly sensitive and thus
can detect low quantities
of the compound in
question.
It requires expensive and
somewhat sophisticated
equipment.
Fluorescence Preferred Detection Method
Advantages of Fluorescence:
 Highly sensitive technique Up to 1,000 times more
sensitive than UV / visible spectroscopy. Therefore
often used in drug or drug metabolite determinations
by HPLC with fluorimetricdetector.
 Selective versatile technique Since excitation and
emission wavelengths are utilised, gives selectivity to
an assay compared to UV / visible spectroscopy.
Possible Separation Methods
Technique
Advantages
Disadvantages
HPLC
High
Performance
Liquid
Chromatography
GC
Gas
Chromatography
CZE
Capillary Zone
Chromatography
Speed (minutes), High
resolution, Sensitivity (ng
to fg), Reproducibility of
+/- 1%, Accuracy,
Automation
Cost, Complexity, Low
sensitivity for some
compounds, Irreversibly
adsorbed compounds not
detected, Co-elution
difficult to detect
Highly accurate and fast
Expensive and complex
instrument, easy to
overload phase, careful
attention required
rapid separation speeds,
high efficiency, very small
amount of sample is
required
Fairly new technique, still
developing
Separation Method of Choice
 Reverse phase HPLC
coupled to a Hg-specific
detector (fluorescence,
photometry or other
elemental detectors).
 Using an eluent of
methanol-10 mM sodium
acetate buffer (80:20, pH
6.2) containing 0.1 mM 2mercaptobenzothiazole
(MBT).
 C18 column, UV detection
at 285 nm.
 Detection limit for Hg is
0.5 ng
Gemini 5µm C18 110A HPLC
Mercury Cartridge 10 x 2.0
mm 10/Pk8
HPLC Schematic9
Conclusion
 By using analytical methods the mercury in these
creams can be quantified then we can find out how
toxic/dangerous these creams really are in hopes of
finding a correlation to certain health disorders in
communities in which these creams are sold.
 For my analyses HPLC coupled with a fluorescence
detector would yield the best separations due to its
high specificity, sensitivity, rapid sample analyses
and sufficient detection limit for this problem.
References
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Wells, A.F. (1984) Structural Inorganic Chemistry, Oxford: Clarendon Press. ISBN 0-19-855370-6.
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http://www.chemistry.adelaide.edu.au/external/soc-rel/content/hplc.htm
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