Lawn chemicals

We moved four dogs up here with us in summer. The youngest was a big golden, very nice, a gentleman, who felt like he had to guard our girls. A golden something, he was large, might have had some pit in him, but he was mostly something else, short-haired. Anyway he died of cancer, less than five months after moving here. Cancer. Some people say it could be lawn chemicals; others say, no, that was too little time for lawn chemicals to get inside him and do that much damage.

His head began swelling and when we took him to the vet, they identified it as cancer. We've all been somewhat mourning him since we had to take him in last month.

I vowed, when I left the area, that pesticides in particular would be the downfall of this area (actually we lived in southern Illinois and I had lived in Iowa as well), but I never really did my research. I know that they are putting Roundup on all the fields. I know that corn fields in general are soaking up more pesticide than any of us could imagine. What I don't know is if this could kill a dog, or a kid, or anyone who got too close to it. I can sense that there's plenty of it around. I can see lawyers circling to sue Roundup for the damages it's caused. What I don't know is whether this specific area has that specific problem, or if our dog, Ballou, could have been victim of it.

If not that, what could it be? I am just wondering.