A local chemical plant produces pesticides that can cause sterility in small mammals such as otters  Soon after the plant began operating, the incidence of sterility among the otters that swim in a nearby river increased dramatically
Ttherefore, pesticides are definitely contaminating the river
A diet low in calcium can cause a drop in egg production in poultry. When chickens on a local farm were let out in the spring to forage for food, their egg production dropped noticeably. So the food found and eaten by the chickens is undeniably low in calcium.