Monday, March 3, 2008
Cigarette Smoking and Depletion of Vitamin C. (UV Spectroscopic Study.)
It is being pointed out that acetonitrile as one of the constituents of cigarette smoke and as a pollutant in the environment from many industries destroys one of the most important anti-oxidant (Vitamin C) of human system. The deficiency of Vitamin C has been related with many diseases. We have pointed out that the destruction of Vitamin C in the Human Respiratory tract by acetonitrile may aggravate coughing and secreting large amount of mucins which may further result in the deficiency of other very important anti-oxidants e.g., Vitamin E, present in epithelial lining fluid.
Key Words
UV spectroscopy, Smoking, Acetonitrile, Vitamin C, Respiratory tract, Human health
Introduction
“Smoking is injurious to health” in spite of this warning, the mankinds love for cigarette smoking has hardly diminished. Ayaori etal. [1]have listed lots of diseases with cigarette smoking and the efforts to educate public about its various harmful effects continue. While studying the anti-oxidant role of Vitamin C we have come across some very useful piece of observation which we feel may add to the pool of existing awareness. According to Erickson Cigarettes smoke is known to contain about 4700 chemical compounds, some of them are oxidants even highly carcinogenic [2]. We wish to point out about a particular chemical; acetonitrile, which has been identified as a part of cigarette smoke and one of the environment’s pollutant. Becker & Lowenheim etal. have reported that combustion of straw, wood and other vegetable produces acetonitrile and it is one of the byproduct of commercial synthesis of acrylonitrile .This means all acrylonitrile based paints consists acetonitrile as one of the major impurity and persons involved in painting may be seriously exposed to the inhalation of acetonitrile. It is reported by Dalhamn that 74% of inhaled acetonitrile is absorbed when smoke is held in the mouth for 2s (and not inhaled) whereas 91% is absorbed when the smoke is inhaled. The presence of acetonitrile in the body fluids of smokers have been identified while in the body of the non-smokers it is essentially absent [ AL Gross]. The quantity of acetonitrile in the urine have been suggested to be a better indicator of exposure of cigarette smoking rather than the number of cigarettes smoked. Baud etal have concludede that the presence of acetonitrile in the blood is a better marker than other tests. These observations clearly suggest that cigarette smoking injects acetonitrile in the human body. Cigarette smoke enters in the human body through respiratory tract. The major components of respiratory tract are epithelial cells, Respiratory tract lining fluids (RTLFs) etc. RTLFs are a heterogeneous group of substances covering epithelial cells from nasal mucosa to alveoli. Carroll and Cross identified that antioxidants and some other components of the system contained in RTLFs are expected to provide an initial defence against inhaled environmental toxins. One of the major antioxidant in RTLFs is Vitamin C. Several observations support an antioxidant role for ascorbic acid in RTLFs. Frei etal have found that the decreased systemic ascorbic acid levels and its increased turnover seen in cigarette smokers appear to be mainly caused by increased RTLF Vitamin C utilization subsequent to its oxidation by oxidants contained in the gas phase of cigarette smoke.
It is known that Vitamin C decomposes reversibly from ascorbic acid → ascorbate anion → dehydroascorbic acid in the body. All the constituents of this equilibrium play their defined role so long their level of concentration as defined by the equilibrium constant, is maintained. If the concentration level of dehydroascorbic acid increases to a very high level, it decomposes reversibly to oxalic acid and 2, 3 diketogulonic acid and thus the body is deprived of ascorbate anion and ascorbic acid. The high level of presence of oxalic acid chelates with calcium ions present in the body to form calcium oxalate (called stone).
Materials and methods. All the solvents used were either spectrograde quality or purified extensively before use. Vit.C purchased from E. Merck was recrystallised before use. UV spectra were recorded on Cary 100 UV-VIS spectrophotometer in closed 10 mm path length cells. Spectra with different batches were identical.
Results and Discussion
We have studied the decomposition of Vitamin C in acetonitrile through UV spectroscopy. The solution of Vit.C ( ~ 1.6 x 10-4 M ) in acetonitrile was allowed to decompose in the cavity of the spectrophotometer and gradual fall in the intensity was monitored over a period of time. Comparable amount of Vitamin C was allowed to decompose in acetonitrile and water. The decomposition was monitored by measuring absorbencies. It was observed that about 90% of Vitamin C decomposed in 1 hour in acetonitrile while in water even after 6 hours 20-25% of Vitamin C was still there.
Concentrated sulphuric acid was added to both the cells in the sample compartment to raise pH level to about 4.0. In the case of water a stable spectra due to ascorbic acid was restored immediately while in the case of acetonitrile no spectra either due to ascorbic acid or ascorbate was restored. The decomposition continued but with reduced rate. This indicates that decomposition of Vitamin C in acetonitrile is a function of the property of acetonitrile itself.
Conclusion
We conclude our observation that acetonitrile being a component of cigarette smoke and as pollutants in environment depletes the level of Vitamin C in RTLF. As a result of this deficiency the constituents of RTLF are not able to perform their role of anti-oxidant effectively e.g. May has pointed out that Vitamin C reduces a-tocopheroxyl radical to a-tocopherol (Vitamin E). Therefore the condition of people suffering from cough etc gets aggravated in the form of secretion of higher level of mucins which may result in the depletion of other anti-oxidant in RTLF and aggregation of inflammatory conditions of the respiratory tract.
Keynotes
The following point refers to the already known observations;
1. Acetonitrile is a constituent of cigarette smoke and environmental pollution.
2. Cigarette smoking is injurious to human health.
3. Vitamin C has been claimed to be one of the most important anti-oxidant of human system.
The following points add new observation;
1. Acetonitrile destroys Vitamin C irreversibly.
2. The deficiency of Vitamin C by acetonitrile in respiratory tract system may aggravates coughing.
3. Secretion of large amount of mucins during coughing may result in the deficiency of other anti-oxidant present in the respiratory epithelial lining fluid. This may create further complications in our respiratory tract system.
References
Ayaori M, Hisada T, Suzukawa M, Nishiwaki M. (2000) Plasma Levels and Redox Status of Ascorbic Acid and Levels of Lipid Peroxidation Products in Active and Passive Smokers. Environmental Health Perspectives; 108 (2), 105-108.
Becker K. H; Ionescu A. (1982) Acetonitrile in the lower troposphere, Geophysical Research Letters 9 (12), 1349-1351.
Carroll E, Cross A, Charles A, Louie S, Halliwell B. (1994) Supplements 102, Number S10 Environmental Health Perspectives .
Dalhamn T, Edfors M. L, Rylander R., (1968) Retention of cigarette smoke components in human lungs. Arch. Environ Health, 17, 746-748.
Erickson B., Anal. Chem. (2006) 3487.
Frei B, Forte T. M, Ames B. N, Cross C. E., (1993) Gas phase oxidants of cigarette smoke induce lipid peroxidation and changes in lipoprotein properties in human blood plasma: protective effects of ascorbic acid. Ann. NY Acad. Sci., 686, 72-90.
Gupta S, Kumar S, Chandra H., (2005) Study of Autoxidation of Ascorbic Acid in Acetonitrile by Electronic Absorption Spectra. J. App. Spect. 72(2), 291-293.
Lowenheim, F. A., and Moran, M. K. (1975) Faith, Keyes, and Clark's Industrial Chemicals. 4th ed. p. 496-501 New York: John Wiley & Sons.
May, J. M., (1999) The FASEB Journal 13, 995-1006.
HOW WELL YOU KNOW YOUR FRUITS & CHEMISTRY
(A)Strawberries (1/2 cup)
(B) Orange (1)
(C) Guava (1)
ANSWER:Oranges are a great source of Vitamin C! One orange actually has all the Vitamin C you need for the day! 1 medium size guava has 165 mg of Vitamin C - WOW!! You would only have to eat 1/3 of a guava to get all the Vitamin C you need for the entire day!! So let's move on...
QUESTION 2 How many servings of fruits & vegetables should we eat in a day?
a. Only one
b. Three
c. Five or more
ANSWER:For the best health, we should have5-9 servings of fruits and vegetableseach day. Be sure to eat a variety of colors to get a variety of nutrients!! You are doing great! Let's keep going...
QUESTION 3 Which of these fruits has the MOST fiber?
(A)Grapes (1 cup)
(B)Apple with Skin (1)
(C)Lettuce (1 cup)
ANSWER:1 medium apple has 3 grams of fiber...but you have to eat it with the skin on! That's where all the fiber is!Wondering how much fiber you need in a day? If you are younger than 18, just add 5 to your age and that is how many grams you need each day.For example: 10 years old + 5 = 15 grams of fiber each day Ready for the next question? Here it is...
QUESTION 4 Which of these vegetables is a good source of the antioxidant, beta carotene?
(A)Carrot (1 medium)
(B)Potato (1 medium)
(C)Green Bell Pepper(1/2 cup)
ANSWER:Can you believe it!?!? Scientists have found OVER 900 different chemicals in fruits & vegetables that may be able to prevent disease! And the list is growing! These chemicals are often called "phytochemicals" ('phyto' meaning plant). They work with the other nutrients and fiber in fruits and vegetables to prevent disease like heart disease and cancer. Some of these phytochemicals can also help your immune system fight sickness and keep your bones strong and not brittle. The list of benefits of phytochemicals is LONG...so eat a variety of fruits & vegetables to get all of the benefits.
ORGANIC MADE EASY
LEARN DISTINGUISH BETWEEN TWO COMPOUNDS
- IODOFORM TEST
- IDENTIFICATION OF DIFFERENT FUNTIONAL GROUP CONTAINING COMPOUNDS
PROPERTIES:
- FOR COMPARISON OF ANY PROPERTY
- CHECK TARGET BOND
- SEE SIMILAR & DIFFERENT GROUPS IN TWO COMPOUNDS
- INTERPRET THE PROPERTY
PREPARATION OF COMPOUNDS
USES OF TYPICAL COMPOUNDS
REFERANCES FOR CHEMISTRY
ABC CHEMISTRY
A TO Z CHEMISTRY
DINESH COMPREHENSIVE CHEMISTRY
PRADEEPS CHEMISTRY
ABSRACT OF CHEMISTRY BY R.V.VERMA
MONTHLY MAGAZINE EDUCATION PLUS
SAMPLE PAPERS:
TOGETHER WITH CHEMISTRY
STAY AHEAD IN CHEMISTRY
ENRICH YOUR CHEMISTRY
TATA MC GRAW
XAM IDEA
HOW TO STUDY CHEMISTRY CLASS XII
- TYPES OF SOLIDS
- TYPES OF UNIT CELL & DENSITY
- DEFECTS
SOLUTIONS(5MARKS)
- CONCENTRATION
- COLLIGATIVE PROPERTY-
- WITH NAME OF SOLUTE
- WITHOUT NAME OF SOLUTE
ELECTROCHEMISTRY(5MARKS)
- CONDUCTANCE & CONDUCTIVITY
- NERNST EQUATION
- ELECTROLYSIS
- CELLS
CHEMICAL KINECTICS(4MARKS)
- RATE EXPRESSION
- ORDER &MOLECULARITY
- INTEGRATED RATE EQAUTION & HALF LIFE FOR
- I ORDER
- O ORDER
SURFACE CHEMISTRY(4MARKS)
- ADSORPTION & ABSORPTION
- COLLOIDS & TYPES & PROPERTIES
- EMUSTIONS
GENERAL PRINCIPLES & PROCESSES OF ISOLATION OF ELEMENTS(3MARKS)
- FORMULA OF ORES
- BASIC PRINCIPLE OF PROCESS-CONCENTRATION & PURIFICATION
- TYPICAL -EXTRACTION OF GOLD ;DEPRESSANT IN FROTH FLOATION PROCESS
COORDINATION COMPOUNDS(3MARKS)
- IUPAC & ISOMERISMCLASSIFICATIO
- VBT & CFT
- USES
POLYMERS(3MARKS)
EXAMPLES
CLASSIFICATION
STRUCTURE OF MONOMERS & POLYMERS
BIOMOLECULES(4MARKS)
- CARBOHYDRATES
- LINKAGE IN DI SACCARIDES
- GLUCOSE STRUCTURE ELUCIDATION
- ANOMERS
- PROTEIN -AMINO ACIDS,PEPTIDE LINKAGE, STRUCTURE
- VITAMINS
CHEMISTRY IN EVERYDAY LIFE(3MARKS)
- EXAMPLES OF EACH CLASS OF MEDICINE
- NO STRUCTURE
- MEANING OF SPECTRUM
- DETERGENTS -DEFINITION &CLASSIFICATION
P-BLOCK(8MARKS)
- REFER FOR INORGANIC MADE EASY
D-BLOCK &F-BLOCK ELEMENTS(5MARKS)
- 16 PROPERTIES
- PREPARATION OF POTASSIUM PERMANGANATE & POTASSIUM DICHROMATE
- LANTHANOIDS CONTRACTION ,CAUSES & AFTER EFFECTS
- LANTHANOIDS & ACTINOIDS
ORGANIC CHEMISTRY
- NAME REACTION
- DISTINGUISH BETWEEN DIFFERENT COMPOUNDS
- MECHANISMS
- PREPARATION
- PROPERTIES-
- REFER TO ORGANIC MADE EASY
Wednesday, February 27, 2008
BEAUTY
ANYTHING THAT IS NATURAL AND INNOCENT BEAUTY LIES IN IT
BEAUTY LIES IN THE INNOCENT FACE OF WOMAN
BEAUTY LIES IN THE SMILE OF A CHILD
BEAUTY LIES IN ANYTHING THAT COMES FROM HEART
BEAUTY IS NOT ONLY PHYSICAL BEAUTY
THE PURITY OF SOUL IS BEAUTY
BEAUTY IS TO SEE , BEAUTY IS TO FEEL
BEAUTY IS NOT TO TOUCH
THAT IS WHAT BEAUTY IS ALL ABOUT
LIST OF CHEMISTRY PROJECTS FOR CLASS XII
QUALITATIVE ANALYSIS
- COCONUT WATER
- SOFT DRINKS
- HONEY
- ASH OF PLANTS
- BONE
- TOOTH PASTE
- DIWALI CRACKERS
- HOLI COLOURS
- SHAMPOO
- ALOE VERA
- MOUTH WASH
- FRUIT JUICES
- ALMOND
- PAPAYA
VOLUMETRIC ANALYSIS
- ALKALINE NATURE OF SOAP/DETERGENTS
- POLLUTANTS IN WATER SAMPLE
- GLUCOSE CONTENT IN BISCUIT
- ASPIRIN CONTENT IN MEDICINE
- AMOUNT OF ANTAACID IN TABLETS
- AMOUNT OF ASCORBIC ACID IN CITRUS FRUITS
CHROMATOGRAPHY
- CHALK CHROMATOGRAPHY
- PIGMENTS OF FLOWER
- COLOURED PENS
- JUICES OF FRUITS/VEGETABLES
ADSORPTION OF ACETIC ACID ON ACTIVATED CHARCOAL
AMOUNT OF KOH IN BANANA PEELS
SEPARATE CASEIN FROM MILK SAMPLES
SEPARATE CAFFEINE FROM TEA
FERMENTATION OF FRUIT JUICES/FLOUR
CONTENT OF PROTEIN IN VARIOUS PROTEIN SAMPLES
PREPARATION OF PAINTS AND PIGMENTS
PREPARATION OF COORDINATION COMPOUNDS
TIPS ON SUCCESSFUL CONVERSATION
- ADOPT A FACE TO FACE METHOD
- BE A GOOD LISTENER
- DO NOT INTERPRET
- BE RESPONSIVE
- MODULATE THE VOICE
- OMIT UNFAVOURABLE REFERENCES TO THE PAST
- GIVE ADVICE ONLY WHEN IT IS SOLICITED
- AVOID NEGATIVE COMPARISON
- APPLAUD WHAT YOU LIKE AND IGNORE WHAT YOU DO NOT
GUARD YOUR WORDS AND YOUR WORDS WILL GUARD YOU
INORGANIC MADE EASY
- Remember first and the last element of the group
- When first & any element of group is compared then exceptional properties are due to anamolous behaviour
- When last & any element of group is compared then exceptional properties are due to inert pair effect
- Any compound if fumes in air it is due to formation of HCl
- Any question related to angle of bond see the position of bonded electrons on the central atom and size of atom if all electrons-bonded & lone pairs are concentrated on atom & size is small so repulsions & angle increases if not angle is less
- Any compound has different bond length it is due to different types of bonds
- Any compound is passive towards a reagent only if it forms oxide layer
- If last element shows exceptioal properties it is due to presence of poor shielding orbitals
- A compound is more covalent if it has more oxidation state
- Proticity means number of OH bonds
- For predicting oxidant or reductant property of any elememt in compound check:
- group of element
- max. & min. oxidation state it can show
- what oxidation state it is showing in given compound & answer
- if max. it will be oxidant :if min. it will be reductant: if intermediate it will be both
ACTION
HALF-HEARTED ACTION IS INCOMPLETE WORK LEADING TO UNSATISFACTORY RESULT AND WASTAGE OF TIME.
IF YOU WOULD HAVE A THING WELL DONE DO IT YOURSELF
BRAVE ACTIONS NEVER WANT A TRUMPET
THE WORLD IS PURIFIED NOT BY ACTION, BUT NOBLENESS OF LIFE
THE ONLY MAN WHO NEVER MADE A MISTAKE WAS A MAN WHO NEVER DID ANYTHING