Communicable diseases: larvicide for drinking water: practice question

A PSM question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

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PSM · Communicable diseases: larvicide for drinking water

Sample item

Which larvicide can be safely added to stored drinking-water containers to control Aedes breeding?

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

A. Temephos

Temephos, an organophosphate, is used at about 1 ppm in drinking-water containers because it is of low mammalian toxicity at this dose. Paris green is an arsenical and is not suitable for drinking water. Oils foul the water.

Option by option

  • A. Temephos (correct)

    Correct. Temephos is safe for potable water at the recommended dose.

  • B. Paris green

    Paris green contains arsenic and is unsuitable for drinking water.

  • C. Diesel oil

    Diesel oil would foul the water and make it undrinkable.

  • D. DDT

    DDT is an adulticide with persistent toxicity and is not used in drinking water.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

More PSM questions

Questions about this PSM question

What is the answer to this PSM question?

The best answer is A, Temephos. Temephos, an organophosphate, is used at about 1 ppm in drinking-water containers because it is of low mammalian toxicity at this dose.

Why is "Paris green" not the answer?

Paris green contains arsenic and is unsuitable for drinking water.

Why is "Diesel oil" not the answer?

Diesel oil would foul the water and make it undrinkable.

Why is "DDT" not the answer?

DDT is an adulticide with persistent toxicity and is not used in drinking water.

What concept does this question test?

It tests Communicable diseases: larvicide for drinking water in PSM. Paris green is an arsenical and is not suitable for drinking water. Oils foul the water.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Communicable diseases: larvicide for drinking water?

Practise biostatistics with small calculations until sensitivity, predictive values and risk measures are automatic. Then use the flashcards and the other PSM questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.