I recently built a HERMS coil out of 50' of 3/8ths copper tubing. In an effort to clean and sanitize the coil, I ran a loop of Starsan through it overnight. In the morning I took a look and the Starsan solution was green/blue in color. Some google searching seems to indicate that this is/was Verdegris, which from my searches is something that is toxic.
What is the correct procedure I should follow to ensure that my HERMS coil is safe for brewing? I don't want to be mashing my grain with toxins