I rode my horse on sprayed grass

I just found out that yesterday the grass at my barn was sprayed, and that we should stay off of it. Unfortunately, I rode earlier today on it for about a half hour. I did not let my horse eat any of the grass, however I am concerned because the chemicals were most likely touching his legs. After I found this out, I immediately rinsed off his legs and washed them with a conditioning shampoo, but I am just wondering if there is anything else I should have done to protect my horse, or if he will be fine. Thanks!

Id make a few quick phone calls to the local pesticide company that sprayed your grass about the contents of their pesticide and ask if your horse is at any risk. If they say yes or they dont know, call your vet and speak to them and they will advise you and if necessary check him over. otherwise keep a close eye on him for the next 7-10 days.