Antiseptics and disinfectants either kill or prevent growth of micro-organism. Identify which of the following statements is not true?

(A) Disinfectants harm the living tissues.

(B) A 0.2% solution of phenol is an antiseptic while 1% solution acts as a disinfectant.

(C) Chlorine and Iodine are used as strong disinfectants.

(D) Dilute solution of boric acid and hydrogen peroxide are antiseptics

(E) Iodoform is also used as an antiseptic for wounds.

Choose the correct answer from the options given below:

(C) only

The correct answer is option 1. (C) only.

Let us now look at each of the given statements:

Statement (A): Disinfectants harm the living tissues.

This statement is true. Disinfectants are chemicals used to kill microorganisms on inanimate objects and surfaces. They are too harsh to be applied to living tissues because they can cause damage such as irritation, burns, or other harmful effects. For example, bleach and phenol at high concentrations are effective disinfectants but are harmful to human skin.

Conclusion: This statement is true because disinfectants are meant for non-living surfaces and are harmful to living tissues.

Statement (B): A 0.2% solution of phenol is an antiseptic while 1% solution acts as a disinfectant.

This statement is true. Phenol is used in different concentrations for different purposes:

At low concentrations (e.g., 0.2%), phenol is used as an antiseptic, which means it is safe for use on living tissues, such as skin, to prevent infections by killing or inhibiting the growth of microorganisms.

At higher concentrations (e.g., 1%), phenol is too harsh for use on living tissues and is instead used as a disinfectant to clean surfaces and inanimate objects by killing microorganisms.

Conclusion: This statement is true because the lower concentration of phenol is an antiseptic, and the higher concentration acts as a disinfectant.

Statement (C): Chlorine and Iodine are used as strong disinfectants.

This statement is not true. Chlorine is indeed a strong disinfectant. It is widely used to disinfect water (e.g., in swimming pools, drinking water) and surfaces by killing bacteria, viruses, and other pathogens. It is very effective and commonly used in public sanitation. While iodine can kill microorganisms, it is primarily used as an antiseptic, not a strong disinfectant. Iodine is commonly used in solutions like tincture of iodine for treating wounds and preventing infections. It is safe for use on living tissues, which means it’s classified as an antiseptic rather than a disinfectant.

Conclusion: This statement is not true because while chlorine is a strong disinfectant, iodine is primarily used as an antiseptic, not a strong disinfectant

Statement (D): Dilute solution of boric acid and hydrogen peroxide are antiseptics.

This statement is true. A dilute solution of boric acid is used as an antiseptic, especially in the treatment of minor cuts and eye infections. It has mild antibacterial and antifungal properties. At low concentrations (typically around 3%), hydrogen peroxide is used as an antiseptic for cleaning wounds and preventing infection. It works by releasing oxygen, which helps kill bacteria.

Conclusion: This statement is true because both boric acid and hydrogen peroxide in dilute forms are used as antiseptics.

Statement (E): Iodoform is also used as an antiseptic for wounds.

This statement is true. Iodoform (CHI₃) was historically used as an antiseptic in wound dressings due to its ability to kill bacteria and prevent infections. While it's not commonly used today due to the development of better antiseptics, it was indeed used in the past for this purpose. Therefore, iodoform was recognized as an antiseptic.

Conclusion: This statement is true because iodoform was historically used as an antiseptic, though it is less common today.

The statement that is not true is (C) only. Hence, the correct answer is option (1): (C) only.