SPECTROSCOPIC TECHNIQUE IN ANALYTICAL CHEMISTRY
KIM 3401
GROUP MEMBERS;NAME UK NUMBER
SIM FONG CHIT UK 24791
NURUL SYAZDIANA BINTI MOHD ZUKI
UK 26258
NORSHARINA BINTI MOHD PESOL UK 25643
(Flow Injection Hydride Generation Atomic Absorption Spectrometry)
What is ARSENIC?
Found naturally in rocks and soil, water, air, and in plants and
animals.
Has no taste or smell
Arsenic 33rd element in Periodic Table. Highest priority contaminant. Refer:
http://www.atsdr.cdc.gov/SPL/index.html Known as poison and human carcinogen. Long-term exposure:
change the way cells communicatedevelopment of diabetesCancerlung disease
Arsenic
Inorganic form found in industry, and in arsenic-contaminated water. It tends to be more toxic and has been linked to
cancer.
Organic form are much less toxic than the inorganic arsenic compounds and are not thought to be linked to cancer. found in some foods, such as fish and shellfish.
How are people exposed to Arsenic?
At workIn the community
In drinking water
In food
CASE STUDY
CHRONOLOGY of Arsenic Pollution in West Bengal, India
Arsenic natural geological is present in local bedrock. Using of pesticides, fertilizers in agrochemical field.The Arsenic from pesticides and fertilizers percolated
into the ground.Using of deep tube wells for water supply and power
pump.The deeper the level of groundwater, the higher the
concentration of Arsenic.
CHRONOLOGY cont..The deep tube wells continue pulling up the deep
Arsenic, therefore the situation became worst.People used the water from the tube well,
unknowingly they were transferring the Arsenic to their body.
Epidemiological study was carried out. Water samples were obtained from the tube wells.
0.84 million people exposed to Arsenic, 0.14 million people suffering arsenical skin lesion.
Effect of Arsenic in humanCancer in the skin, lungs, bladder and kidneySkin changes such as thickening and pigmentationBlackfoot disease
How to prevent?
• Diet• Change the way to cook the rice• Vary with other grains
INSTRUMENTATION
Flow InjectionHydride Generation
Atomic Absorption Spectrometry(FI-HG-AAS)
FLOW IN JECTION
AAS
HG-AAS
http://www.shsu.edu/~chm_tgc/sounds/sound.html
Advances of InstrumentFlow injection• consists of two peristaltic pumps
1. for pumping the carrier and reducing agents 2. for pumping the sample solution.
• A certain volume of the sample injected into the flow of carrier liquid
Hydride Generation• the volatile sample is stripped from the analyte solution and
carried out by a gas into the atomizer.
• This strip is followed by chemically converting the analyte to hydride vapor form.
Flow Injection Hydride Generation Atomic Absorption
Spectrometry
Inductively-Coupled Plasma Mass Spectrometry
Detection limit 0.02µg/L 0.2 µg/L
Nebulizer Nebulizer is not required Nebulizer is required
Precision 0.1-1% 1-3%
Dissolved solids maximum concentration
0.5-3 0.1-0.4
Chlorine interference Less More (1µg/L for each 100mg/L)
Linear dynamic range 103 105
Sample throughput 15seconds/elements 2-6minutes all elements
Operation cost Low High
Advantages of FI-HG-AAS
• low detection limits• quite fast measurement• most of interferences disappear when the analyte is
transferred to a gaseous state
Disadvantages of FI-HG-AAS
• the specific chemical form of the analyte is required• high concentrations of Cu, Ni, platinum group metals and other
transition metals cause serious interferences• a large excess of the hydride-forming element makes
determination of traces of the other one impossible
CONCLUSION