I think the worst thing is that if any of the lubrication leaked into the tank...that would be majorly bad! Although to be honest, Im not sure if lube is used at all in some of these new heads, but I have heard of things like this happening in the past.
I probably haven't helped much...lol...but see if there is any kind of "oil slick" looking fluid anywhere. Other than that, I'm not sure if there are any other toxic parts that could pollute the water.
Either way, ya got a bump here...