From 1952-1953, Sydney detectives investigated a staggering number of murder and attempted murder cases that were unrelated yet shared a common element: thallium poisoning.
从 1952 年到 1953 年，悉尼侦探调查了数量惊人的谋杀和谋杀未遂案件，这些案件互不相关，但却有一个共同的因素：铊中毒。
The secret to thallium toxicity lies in its structural similarity to potassium — an element that helps regulate the body's fluids, initiate muscle contraction and transmit nerve signals.
铊毒性的神秘在于其结构与钾相似——钾是一种有助于调节体液、引发肌肉收缩和传递神经信号的元素。
If even a small amount of thallium sneaks its way into the body — for example, through a tainted tea or a slice of cake — it easily supplants potassium, causing the body to slowly and painfully shut down.
哪怕是少量的铊潜入人体——例如通过一杯毒茶或一块蛋糕——都能轻易地取代钾，导致人体缓慢而痛苦地停止运转。
At the time, thallium's risks were well known, so how were the perpetrators able to get their hands on such a lethal element?
当时，铊的危害是众所周知的，那么犯罪分子是如何得到这种致命元素的呢？
And thallium isn't the only dangerous element on the periodic table.
铊并不是元素周期表上唯一的危险元素。
Within this tabular array loom several potential threats, each with their own unique method of imposing destruction.
Some elements, like thallium, are dangerous due to their toxicity.
Once they enter the body, they wreak havoc on the biological systems that keep us alive.
Lead, for example, switches places with the body's essential metals like calcium, in turn disrupting neuronal communication in the brain.
Traveling through the bloodstream, it also generates toxic levels of molecules known as reactive oxygen species, which over time can stress and kill cells.
