You can avoid some of the toxicity of DEET by applying it to clothing rather than skin, but I wonder what that will do to your nice lycra shorts and wicking jersery:
[QUOTE=SadieKate]Unfortunately, DEET is the best but it ain't pretty stuff. We stay away from it because it destroys the plastic on our flyfishing lines.

I was doing a web search to find the brand name of the Yank essential oil-based repellent which has tested most effective and came across a UK product called Shoo! I don't know how to insert links - the web address was www.shoo.org.