By Tobias Carroll Can one have a timely warning about something that endures for centuries? The increasing levels of concern over forever chemicals polluting different food supplies — including fish in Lake Superior — are one more effect of pollution to be concerned about. The chemicals, known as PFASs, earned their nickname because, by and large, they don’t break down in natural environments. There are some sources of pollution that can be managed or minimized when placed in the right environment. These? Not so much. And they have a tendency to get into the food we eat. A new report at The Gu…