If the Copyright Office has no confirmation that a composer or song-writer is still living and it has been 75 years since the first copyright protection order was granted, or 100 years since the recognized creation date of the piece, it becomes public domain.
Exposure to blue-green algae can cause rashes, skin and eye irritation, allergic reactions, gastrointestinal upset, and other effects. At high levels, exposure can result in serious illness or death.
Some blue-green algae produce toxins or poisons. In their toxic form, blue-green algae can cause illness in humans, pets, waterfowl, and other animals that come in contact with the algae. Toxic blooms can kill livestock and pets that drink the water.