Canary in a coal mine?

Since our dog Charlie was diagnosed with cancer two months ago, we have spoken with many pet owners who have had similar experiences. Their dog or cat was doing just fine and then one day there was a lump, or bleeding from the mouth. Within a few days, weeks or months, their beloved pet was dead, often before reaching ten years of age. It seems that pets who live long healthy lives and then die of old age are the exception these days, but I can't remember this always being true.

All these tragic early deaths make me wonder what the cause might be. Have we poisoned our environment so terribly that it is killing our pets? I know that Charlie will eat anything that seems remotely edible, including grass, sticks and garbage, so is it possible that his eating habits have resulted in the osteosarcoma growing in his upper jaw? The half-dozen veterinarians we have consulted don't know why he has it, and they're frankly surprised to see a cancer that normally attacks appendages take hold where it has. He has been through two chemotherapy treatments now, but they don't seem to be helping. The tumor in his mouth cavity has been removed twice, but it keeps regrowing and is now the biggest it has been, about the size of my thumb.

Charlie had a clear chest x-ray yesterday, indicating that the cancer has not yet spread to his lungs. He is scheduled to have the tumor "debulked" again tomorrow, and he is scheduled for a third chemotherapy treatment next Thursday. We're hoping the treatments will prevent, or at least slow, the growth of the tumor and the spread of the cancer, but based on what we have seen so far, that doesn't seem likely.

If our pets, who live protected, supervised lives, are being poisoned by the environment, what does that say for wildlife? What chance does it have fending for itself? No wonder we're losing species to extinction at a record rate. What about humans? Will the diseases resulting from our poisonous environment eventually outpace developments in medical technology and reverse gains in life expectancy? If the early deaths of our pets are any indication, we would know that we are already in deep trouble. The canary is already dead.