– Naturally occurring heavy metal
– ‘As’ on the periodic table (atomic no.33)
– Tasteless and odourless
– Untraceable in human body
– Once the method of choice by poisoners
– Marsh Test for detecting arsenic published in 1836
– Famous victims include Napoleon Bonaparte, George III of England and Simon Bolivar
Arsenic is a heavy metal naturally found in the Earth’s crust. It’s a particularly nasty element, because at even very low doses it can poison and kill. Depending on the quantity consumed, death usually occurs within 24 hours to four days (an acute lethal dose is approximately 0.6mg/kg/day – a 23 year old male who ingested 8g of arsenic survived for eight days).
As it is found naturally, it’s a serious hazard (both for food and water). It can seep into groundwater which is particularly risky, particularly if people dig their own private wells/bores without testing the water. Rice products are known for being at risk (that’s why you should wash your rice before cooking). Long-term exposure can result in a variety of cancers amongst other problems.
These days our exposure is lessened as arsenic in common household goods (such as wallpapers, paints and even cosmetics) was phased out in the 1950s.
With a tasteless, odourless and (until the Marsh test) undetectable poison that mimicked the symptoms of a natural illness, it’s no surprise it made murder difficult to prove.
While arsenic is not commonly used in modern times to kill, one of NCIS’ most famous cold cases was murder by arsenic.
Navy Lieutenant Lee Hartley became mysteriously ill while deployed on the USS Forrestal in 1982. He was airlifted to a stateside naval base hospital but he eventually died – an autopsy revealed long term exposure to arsenic.
Investigators couldn’t determine where he was poisoned. He had symptoms and was ill at sea, but then he’d also improved initially in hospital but worsened when discharged.
At first investigators suspected a fellow sailor, as Lt Hartley had been threatened on the ship. “Lieutenant Hartley is a dead man” had been written on a wall of the ship, probably by a sailor Lt Hartley had disciplined.
Because Lt Hartley had been poisoned over a long period of time, this idea was dismissed as it needed to be someone who was close to him. Focus shifted to his roommate on the ship, as he also visited him in hospital and they were both vying for a major promotion.However his friend was eventually cleared as a suspect.
With no other suspects, investigators considered whether the very homesick Lieutenant was self-harming due to mental health issues. However, he was still getting ill when home, so again they had to dismiss this theory.
They next focussed on his wife, however after a lot of investigation and a polygraph which she passed. The case went cold.
In 1995 the case was re-opened. This time investigators realised the polygraph had been incorrectly interpreted, so from the start their investigation focussed on his second wife, Pamela.
This time they uncovered evidence of Pamela being unhappy in the marriage. But they struggled to understand how Lt Hartley fell ill while at sea. Until they discovered Pamela was sending him care packages with cookies.
Pamela Hartley was charged with first degree murder almost 14 years after her husband’s death. She was sentences to 40 years in prison (however, after 15 and a half years she was released).
A famous arsenic case dates back to 1858. The Bradford sweets poisoning contributed to the passing of the Pharmacy Act 1868 in the United Kingdom and other legislation to regulate the adulteration of food.
A sweets maker (peppermint humbugs) regularly substituted “daff” (powdered gypsum) for a portion of the sugar as it was cheaper. One day he sent a man to the druggist to purchase more daff, but the pharmacist was ill and, due to a mix-up, the assistant sold the man arsenic, not daff.
The sweets maker didn’t pick up on the mistake, although he did notice the sweets looked different (he was subsequently sick for days due to his contact with the arsenic). He sold 40lb / 18kg at a discount to a stallholder, who ate one and promptly fell ill, but still sold 5lb / 2.3kg of the sweets from his stall that night.
The Bradford sweets poisoning resulted in the poisoning of over 200 people, with 21 dying as a result.