Question

A threshold value is the dose (or concentration) below which:

A. all effects are lethal. B. no effects can be detected. C. 50% of the exposed population will die. D. 35% of the exposed population will die. 5 points

Answer 1

The threshold value of dose is the dose at which toxic effects are first encountered.

So in the question it is asked it is the value below which:-

So by definition a) option is clearly excluded

for option c ) when 50% population will die it said as LD 50 i.e lethal dose 50 not threshold so it is also excluded.

d) similarly d is LD 30 where 30 % of exposed population will die so it is also out of consideration

Now coming to b) it would be right choice because below threshold value the bodies ability to detoxify is present and not exceeded hence it can detoxify on its own so no effects can be detected.

Answer would be b) part

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