Environmental factors also affect a dog’s life expectancy. For one thing, indoor pets tend to live longer than outdoor pets. This is because living outside can expose the dog to extreme heat, frosts, and cold temperatures. They can also be exposed to other stresses, such as territorial stress. Stress can age a dog more quickly which can reduce his life expectancy.
Other environmental factors should also be considered, such as the dog’s exposure to toxins and chemicals. Dogs and other animals are much lower to the ground than we are, and they also spend a lot of their time sniffing the ground and air. This can mean that Fido is exposed to much more of the pollutants and residues than we are.
Dogs also lick themselves, which means that if there are any toxins or pollutants on his fur, he will ingest it. Ingesting these sorts of chemicals can cause illness, and can be fatal.