INBDE (Integrated National Board Dental Examination) Practice Exam 2026 - Free Practice Questions and Study Guide

Mercury is a highly toxic element that can accumulate in the human body through ingestion or inhalation. The half-life of a substance refers to the time it takes for half of the initial amount of the substance to decay or leave the body. In the case of mercury, the half-life depends on the chemical form of the element and can vary from a few days to several months.

Option A, 70 days, and Option B, 65 days, both have longer half-lives than the correct answer, which means that it would take a longer time for half of the initial amount of mercury to leave the body. This is incorrect because although it is possible for some forms of mercury to have a longer half-life, inorganic mercury, which is the most common form found in the human body, has a shorter half-life.

Option D, 40 days, has a shorter half-life than the correct answer, which means that it would take a shorter time for half of the initial amount of mercury to leave the body. This is incorrect because while some forms of mercury may have a half-life of 40 days, it is not generally the case for inorganic mercury in the human body.

Therefore, the most accurate answer among the