Passage 11: Note Making and Summarizing | Class 11 English Grammar PDF Download

Read the following passage carefully:

1. The recently concluded Kyoto Conference on the production of gases with a greenhouse effect on the environment has again brought into focus the issue involving the chlorofluorocarbons (CFCs).
2. These are widely used for their cooling and propelling actions in equipment such as air- conditioners, fire extinguishers and refrigerators. Most of the CFCs are non-toxic, inert and non-inflammable, therefore, ideal for both domestic and commercial use. In medicine, their use is widespread for general purposes listed above. More specifically, they are used as propellants for inhalational drugs commonly used by patients with asthma and other lung diseases. Millions of patients using metered dose inhalers (MDI) are thus dependent on CFCs—until CFC-free inhalers become available.
3. The inhalational therapy, which almost revolutionised the management of asthma, is apparently in danger. It was in the 1970s when the scientists first discovered that the CFCs were dangerous for the environment. CFCs released in the environment are broken down by the sunlight to release chlorine atoms. It is the chlorine atom which destroys the ozone layer present about 40 km above the earth.
4. The effect is so potent that one atom of chlorine can destroy up to 100000 molecules of ozone.
5. The normally present ozone layer prevents the entry of the extra terrestrial rays on the earth. A hole created in this protective umbrella allows the harmful ultraviolet and other rays to pass unfiltered. This phenomenon is commonly referred to as the greenhouse effect resulting in global warming. The size of the hole which was supposedly of a football ground until a few years ago, has grown to that of Antarctica. That in itself speaks of the enormity of the problem.
6. The contribution of CFC propellants used in medicine to the greenhouse effect is negligible. CFCs used in inhalers are less than 0.5 per cent of its total worldwide use. In fact, propulsion of a single satellite in space releases more chlorine than that by the worldwide use of MDIs for a whole year. Even the Montreal Protocol which introduced total ban on CFCs had spared the essential uses such as that for MDIs.
7. But a ban on CFCs for most of their uses is bound to affect their inhalational therapy. Production of CFCs is likely to stop in the near future. Moreover, a relative scarcity of CFCs is likely to greatly increase the costs of inhalers. Alternative approaches, therefore, are immediately required.
8. Inhalational therapy is now established as an important method of administration of drugs. It is certainly the mainstay for treatment of asthma. But several other drugs, including antibiotics are administered in inhaled forms. CFCs are required only when a drug is available in a premixed form in a canister for direct inhalation. But drugs, other than those for asthma are not available as ready-made inhalers. Most of those drugs, including many used for asthma as well, are given by nebulization which involves the use of compressed air (or oxygen) to change the liquid solution into a vapour-form. But nebulization does not solve the problem as it cannot replace the inhalers.
9. Alternative propellant gases using fluorocarbons without a chlorine atom, are being developed. Fluorine released by these propellants is considered to be safe for the ozone layer. But inhalers employing such gases are yet not available.
10. Another novel technique is to substitute the liquid inhalational drug with a powdered form. Several kinds of dry-powder inhalers are already available in the market. The methodology is easy and simple for the patient but for the problem of dosage. Per dose the amount of drug which can be inhaled in a powder form is generally less than that from an MDI. We have différé .t rotahalers and rotacaps available in India. Elsewhere, in the world, there are disc-halers where a single disc contains multiple (six to eight) blisters of the drug, or a turbohaler where 100 to 200 dosages are made available in a single unit. It is only a question of time when these forms shall be marketed in this country as well. Those are bound to be costlier to absorb the expenses of research, development and marketing.
11. Undoubtedly, better alternatives will be developed in future. Until then, one hopes that the benefits of inhalational therapy with or without the use of CFCs are not denied to the patients.

Q.1. On the basis of your reading of the above passage make notes using appropriate symbols and abbreviations in any one of the accepted formats. Also supply an appropriate title.

Title: Inhalers and Environment
Notes:

1. CFCs & Envt
   (a) dangerous for envt.
   (b) releases Cl – dest. Og
   (c) green-house effect—global warm’g
2. Use of CFCs
   (a) Domestic & commercial
   (i) AC, fridge.
   (ii) fire extg.
   (b) Medicine
   (i) propellants for inhal. drugs
   (ii) MDI for asthma.
3. Inhaler Therapy
   (a) CFC inhal’s – neg. gr’n house eff.
   (b) Trtmt. of asthma.
   (c) Admn. antibiotic in inhaled forms.
4. Alternative Approach
   (a) neb’n
   (b) FCS w’out Cl
   (c) dry powder inhs.—prob. of dosages
   (i) rotahalers & rota caps.
   (ii) disc halers – 6 to 8 dos.
   (iii) turbohalers – 100 to 200 dos.

Q.2. Make a summary of the passage.

Summary:
CFCs is dangerous for environment as it releases chlorine atoms which destroy the ozone layer, causes greenhouse effect and global warming. It is widely used in domestic and commercial purposes. CFC inhalers contribute negligible greenhouse effect. It is not only treatment of Asthma but also administrates antibiotic in inhaled forms. As alternate approaches FCs without chlorine atom are being developed. Another novel technique is to substitute the liquid inhalational drug with a powdered form. Different rotahalers and rotacaps are available in India.