Human-kind’s continued experiments with chemicals have resulted in both prolonged life and hurried death, and while there are rumors of government experiments involving chemicals and reanimated dead, there is little or no proof that these have actually taken place.
If chemicals are ever proven to work in reanimating the dead, the resulting Zombies may be like that of the “Return of the Living Dead” series (reanimated by the chemical “2-4-5-Trioxin”). These Zombies vary greatly from film to film, but do share some things in common; they have the ability to move quickly, use tools, speak, survive damage inflicted on the body and the brain, and they all crave brains to take away the pain of being dead (see Zombease answer 4).
While a Chemical Zombie wont always infect you via biting or scratching, you can contract the affliction from ingesting and/or inhaling the chemical involved or a substantial amount of affected particulates. The blood, flesh, and even the ashes of a Chemical Zombie can remain active and infectious indefinitely, making the spread of the chemicasl and affliction highly likely in almost every situation.
If an individual does ingest or inhale contaminated particulates or the chemical causing the affliction itself, they will soon begin to suffer from chills, a hacking cough, tightness in their limbs, loss of respiration and heartbeat, rigor mortis, and finally total take-over by the chemical. Once the chemical has fully invaded the body and final death has set-in, most victims will lose their sense of humanity and begin seeking brains.
Great care should always be taken when dealing with the body or body-parts of a Chemical Zombie. They should be sealed in an airtight container that is clearly labeled with contents and active emergency contact information. The container should be stored in a lock-down facility located far from settlements, graveyards, and water sources, until a counter measure is found.