Seven is dangerous. FIL lost a co-worker and friend. He dusted his tomato plants with it, scans protective gear, went to work with some still on his hands and clothing. Worked in a steel mill, got all sweaty and passed out, heart failure. EMT's managed to revive him and transported but he coded again on the way in, DOA. Tox screen showed the cause, Seven. 
 
Because he went down in the mill this became a legal issue, depositions and all. The Dr. stated in his that he could have had the same result quicker and probably much less painful if he would have just shot himself in the head. 
 
Don't believe me read the warnings on Seven containers.
 
I have been involved with horse rescue for 30 years. I live close to the biggest horse slaughter auction in the US. Worms can cause colic but Seven is NOT!!! a dewormer. that lady needs to be reported to the humane officer like Yesterday! I've pulled horses from the slaughter pens that had such a parasite load that deworming took a Vet to tube worm them. I primarily work on the first part of rescue, working the auction, identifying the horses there and coordinating with people around the country to find someone who can help, then I quarantine, keeping the horses for only 30 days due to injuries (I do wound care) or if the people who baled them out do not have a facility where they can quarantine them themselves.