Some time back there was an EBay auction for a Polaris display model with a difference. The missile itself seemed normal enough, but the warhead was distinctly unusual. It was a plexiglas cone filled with small metal spheres:
Assuming that this model is truly official (it seems to be, but who knows), then it would appear that Lockheed gave some thought to a Polaris armed with biological or chemical warheads. I would speculate that this probably isn’t a biological weapon… biowar agents are usually fairly slow and you generally want to distribute them quietly, while a SLBM is terribly fast and not at all sneaky. My guess is that the metal spheres are the M139 bomblets, designed to carry 590 grams of Sarin nerve gas. The M139 was loaded on the Honest John and Pershing missiles in the 1960’s. The preceding design was the M134 bomblet, some 334 of which could be carried by an Honest John, as shown in the display piece below:
I have doubts that the Navy would load Sarin or bioweapons on board a submarine… seems to be just asking for trouble. Perhaps this was for a land-transportable missile, carried on a trailer behind a truck. Lockheed tried to sell just such a thing a few times with no success.