What is Arsenic pollution?

I assume you are talking about higher than normal amounts of arsenic in air/water/etc. Arsenic need not be in the metal form (elemental form) to be toxic. Most, if not all, compounds of arsenic are toxic at some level. As2O3 and As2O5, for example, are two arsenic compounds previously used for many years as pesticides and fungicides.

pork?

I'm sorry, but I'm not sure what you mean by "pork." Could you please clarify your question?