Dichlorodiphenyl Trichloro Ethane (DDT) is the first chlorinated organic insecticide for the discovery of its effectiveness as an insecticide Paul Muller was awarded Nobel Prize in Medicine and physiology in 1948. Which of the above statements are correct ? (a) DDT is effective against mosquitos that spread malaria. (b) DDT is effective against lice that carry typhus. (c) DDT has high toxicity towards fish. (d) DDT is not metabolised easily by animals.

DDT (Dichlorodiphenyl Trichloro Ethane) was indeed the first widely used synthetic chlorinated organic insecticide, and Paul Muller was awarded the Nobel Prize in 1948 for discovering its effectiveness against vector-borne diseases. (a) DDT was extremely effective in controlling mosquitoes, particularly Anopheles species, thereby playing a significant role in malaria eradication campaigns in the mid-20th century. This statement is correct. (b) DDT was also highly effective in controlling body lice, which are vectors for typhus, and was used extensively during and after World War II for this purpose. This statement is correct. (c) DDT is highly toxic to aquatic organisms, including fish, even at low concentrations. Its accumulation in aquatic ecosystems was a major environmental concern. This statement is correct. (d) DDT is a persistent organic pollutant (POP). It is highly resistant to degradation in the environment and is not easily metabolized by most animals. It bioaccumulates in fatty tissues and biomagnifies up the food chain, leading to long-term environmental and health impacts. This statement is correct.