Yes, just like human beings, plants can also get copper poisoning.
I continue to use Daconil for early/late blight and anthracnose every 7 days and have never looked back. Ortho and other brands use the same the active ingredient (chlorothalonil which is a chloronitrile fungicide, no copper) which binds up fungal proteins and stops spore germination so the fungi doesn't spread. I spray every 7 days. It is low toxicity and the label says you can spray up to the day of harvest, but my last spray is about a week before harvest. Daconil works well for me - particularly for anthracnose which is a big problem here in SE Michigan. I'm sure the other brands that use chlorothalonil work just as well.
And if you have horrific fungal problems, you can add a copper spray to Daconil (and I'm sure the other brands).
Good luck!
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