US EPA & NIH advise AVOIDING Amdro (HYDRAMETHYLNON) contact with:
water, fish, children/humans, fruit trees, nuts.
Although it takes a fairly large amount of Amdro to be lethal;
studies in cattle & dogs raised some concerns over:
blood-chemistry, cancer, liver-function, immune-system function, ...
Best to keep Amdro away from your children, water, fish, dog, cattle, fruit-trees & nuts.