sugar 🙂

water. Although in the middle ages I guess the cholera would have finished you off before then. How about biological poisonings?

Many “radioactive” toxins are more toxic than radioactive. For metals, I’d say lead or mercury were your choices.

Iocane poison.

Tasteless, odourless and completely undetectable.

It’s the deadliest poison know to man. You can also develop an immunity to it by taking tiny amounts on a regular basis.

Ergot?

Traces back to the Egyptians, through to the middle ages and up to the 1930’s?

Can she play with the age of the planet?

Push it back 2 billion years or so, slightly increase the oxygen conc and make something like the Oklo uranium ore deposits fission reactor.

Start killing people with a host of “natural” stuff like Xenon135.

Ricin from castor beans.
Mushrooms.
Ear wax on a blade or pin for a lovely infection.

Heavy water? Not sure its a killer, i think its just an element used in nuclear devices.

What about a parasite that can be induced to enter the victim’s brain, and slowly munch away at it over the years?

Like a Daily Mail subscription?

gold dust

Ebola?

Or for a lethal STD caused by pierced condom?

*slow clap*

Or for a lethal STD caused by pierced condom?

syphilis

The tobacco barons have mastered slow acting poisons.

Guaranteed to kill you or ruin your physical wellbeing over many years.

Failing that, a boomslang snake could be used for delayed but deadly effects.

blader1611 – Member

Heavy water? Not sure its a killer, i think its just an element used in nuclear devices. Heavy water would kill you eventually, but you’d have to be drinking it by the pint – if you managed to deuterate 50% of your body’s water content that’s reckoned to be enough to see you off.

Bet it’s bin dun, though, as a plot device – seems tailor made for a SF short story and heavy water was pretty well known as a substance in the nuclear era (although not itself radioactive, just isotopic).

Asbestos, though doesn’t the effect come from dust?

Depends on the timeframe; it causes mesothelioma thirty years down the line…

what about carbon monoxide?
http://oem.bmj.com/content/59/10/708.full

or, something along the lines of DDT or tetraethyllead which fat accumulates, followed by a substance to cause slow weight loss. as the body metabolises fat the poison is released and metabolised

Arsenic, again: it was used to make a green dye. In a damp room mould would attack the paper, disposing of the As as a gas, AsH3 I think, somewhat similar to ammonia.

So have a room or house decorated in spring or early summer, because of the mould and damp of the previous winter, then the victim kicks the bucket in the new year.

Napoleon was exiled to St Helena where he lived in a damp house, this has been suggested as a cause of his death.

I half remember Antimony does something similar. And I think the dye was Paris Green.