Poison Darts and World War II

Back in 1941, England looked into dropping poison darts from planes on German troops. This was when Britain was facing a possible Nazi invasion after the fall of France. The National Archives made public formerly top secret documents. They show that plans called for packing more than 30,000 darts into a single cluster bomb that could saturate a zone where enemy forces were exposed. They had already tested the poisoned darts against sheep and goats at a biological weapons station in Canada. However, they were never used again humans for military purposes. Wouldn't that have been horrendous?