I like the unintentional new chlorinated colour, as it reminds me of both artifice (Shamrock Shakes, anyone?) and nature (the humble pistachio).
Tim Walker's dreamscape fashion photography also often reminds me of pistachio, as in these images:
But back to Lochte's hair and the Olympic water, which was not as murky as this Walker image, despite concerns about the diving pool:
Did a breakfast of champions cause Ryan Lochte's change of hair color?
Nah--Ryan just ate green eggs and swam.