What are the approximate Endothall half-lives in water and soil?

• A. Water 5-10 days; soil 7-21 days.
• B. Water 1-2 days; soil 1 week.
• C. Water 30 days; soil 60 days.
• D. Water 100 days; soil 200 days.

Answer: (A)

Endothall’s fate in the environment shows it degrades at a moderate pace, with concentrations dropping by about half over several days in water and over a week or two in soil. In water, hydrolysis, photolysis, and microbes reduce the compound fairly quickly, so a half-life of a few days is typical. In soil, adsorption to organic matter and microbial breakdown still occur, but the process is a bit slower, leading to a span of about one to a few weeks. The choice that aligns with these typical ranges is water about 5–10 days and soil about 7–21 days. Options suggesting much shorter (hours) or much longer (months to years) persistence don’t match how endothall behaves under common conditions.