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.
Green Algae. The most common algae associated with swimming pools is green algae. It is very opportunistic, meaning it will take advantage of any failure in the normal sanitizing program and quickly infest a pool. One will see green algae problems frequently appear overnight following heavy rainstorms.