Here’s a question I’ve been asked several times, and I haven’t had a good answer until Now. Former Orvis Product Developer Tim Daughton explains the variables involved:
“This is a difficult question to answer, as there are so many variables aside from time to consider—UV exposure, temperature, humidity, chemicals (DEET, sunscreen), etc. The one factor that many people fail to consider is heat, especially the kind that is generated in a car trunk or on the deck of a boat in midsummer. These extreme temperatures can, over time, break down the material quickly, even though it is not exposed to UV.
You should store excess leaders and tippet in the house—not your vest—preferably in a cool place; some people even keep them in the freezer. Your vest/pack is actually the worst place to store leader and tippet. Take what you need to fish that day or on that trip, and leave everything else at home.
In general, fluorocarbon is going to last longer than nylon, because fluorocarbon is impervious to UV; it can, however, get milky with prolonged exposure, which makes it more visible to the fish. As a rule of thumb, I would replace material every two years unless it shows signs of degradation—then I would chuck it immediately.”
So now you know. . .and you have a good response ready when your significant other asks why your fishing gear is stored next to the tater tots.