Systems and methods are provided for determining when the seal of a sealed container was broken. Such can include a sealed container with a seal that separates an interior of the container from the outside environment. An environmentally sensitive conductor of an electrical circuit is positioned within the interior of the sealed container. The conductor has an electrical property with a known initial value that changes in a predictable manner as a function of time and exposure to the outside environment. Accordingly, breaking the seal and exposing the conductor to the environment causes the electrical property of the conductor to change. When a present value of the electrical property is determined, it may be used in combination with the initial value and the expected change in the value over time in order to determine the time at which the seal was broken.