Question

Which of the following pesticides is banned these days?
A. Aldrin
B. Endrin
C. DDT
D. Toxaphene

Answer 1

Pesticides are substances that are meant to control pests. Pests include various insects, microbes and other organisms. This pesticide was first synthesized by Othmar Zeidler in 1874.

Complete answer:
In general, a pesticide is a chemical or biological agent that deters, incapacitates, kills, or otherwise discourages pests. Target pests can include insects, weed, nematodes, plant pathogens, molluscs, microbes, etc. DDT is also known as Dichlorodiphenyltrichloroethane. It is a colourless, tasteless and almost odourless crystalline chemical compound. It was initially developed as an insecticide. DDT was first synthesized by the Austrian chemist Othmar Zeidler in 1874. It is extremely effective in killing unwanted insects. It is a stable molecule that can be manufactured by simple and cheap processes. It lasts for a long time in the environment. Some of the disadvantages of DDT are as follows:
1. When DDT gets into our bodies, it is stored primarily in organs like the adrenals (denoting a pair of ductless glands situated above the kidneys), testes and thyroid glands.
2. DDT is also stored in smaller concentrations in the liver and kidneys. At concentration above 236 mg, DDT per kg of body weight, you'll die. The concentration of 6-10 mg/kg leads to such symptoms as headache, nausea, vomiting, confusion and tremors.
3. DDT affects the nervous system by interfering with normal nerve impulses. Therefore, DDT is banned these days.
Hence, the correct answer is option C.

Note: DDT is similar in structure to the insecticide methoxychlor and the acaricide dicofol.
It is highly hydrophobic and nearly insoluble in water but has good solubility in most organic solvents, fats and oils. DDT does not occur naturally and is synthesised by consecutive Friedel–Crafts reactions between chloral and two equivalents of chlorobenzene in the presence of an acidic catalyst.