October 4 is World Animal Day – a global event now in its 99th year that raises awareness of the health threats facing creatures around the globe. One of the biggest dangers comes from the “forever chemicals” known as PFAS, which threaten animals worldwide. Founded by Polish writer and publisher Heinrich Zimmermann, the event first took place in March 1925, and later switched to October 4 in 1929 to coincide with the feast of Francis of Assisi, the patron saint of animals.