Ambergris: perfume from whale poo
Since King Charles I was crowned in 1626, the coronation of British monarchs has involved being anointed with a holy oil or ‘chrism’ made mainly from olive oil perfumed with flowery scents such as rose, jasmine and orange blossom. Traditionally, that oil also contained substances such as musk from deer and civets, plus ambergris from sperm whales. But in line with modern concerns about animal cruelty, the oil used to anoint Charles III at his coronation this month is free of animal products, meaning the new recipe doesn’t contain ambergris.
What’s ambergris?
It’s a waxy substance that forms in the digestive system of sperm whales. Each piece of ambergris has a unique odour that depends on its age and composition.
Its colour ranges from black or brown when new, to white over time. A piece can have a golden hue – like amber – or a grey tint, hence the name ‘ambergris’.
Why is it valuable?
It’s a rare commodity and only appears in about 1 per cent of individuals. In the 20th century, the sperm whale became an endangered species partly due to hunting for products such as ambergris.
Although it is considered an aphrodisiac in some cultures, ambergris is primarily used as a fixative to make fragrances last longer. And while the natural product is more reliable, it’s been largely replaced by synthetic alternatives.
Is ambergris related to amber?
No, but in both cases the core compound is a type of alcohol called a terpene. The two substances are made via different processes: whereas amber is fossilised tree resin, ambergris is probably produced by gut bacteria whose metabolic reactions convert the common molecule squalene into ambrein (the central component of ambergris), which precipitates inside the whale colon as a dense mass called a coprolith (hard faecal matter).
Ambergris’ chemical composition determines its complex odour. Ambrein is an odourless compound that – upon exposure to air, seawater and sunlight – breaks down into two potentially smelly molecules, ambroxide (synthetic brand name Ambroxan) and ambrinol. Steroids, dihydro-ionone and gamma-coronal (aptly named for a coronation!) add musky, flowery and woody notes.
How is ambergris formed?
Nobody knows for sure what triggers its formation. Squid are a major part of a sperm whale’s diet, so one popular hypothesis is that ambergris accumulates in layers around squid beaks to prevent mouth parts from irritating a whale’s gut.
But like the belief that pearls start as sand grains (they often form after injury), that may be a myth. Many whale species prey on squid yet don’t make ambergris.
Where is it found?
Traditionally, it was harvested. During the Antarctic whaling season of 1953, a massive boulder of ambergris weighing 420kg (a possible record-holder) was extracted from the large intestine of a 15m-long male.
Ambergris appears on beaches around the world, but it’s unclear exactly how it ends-up there! And while the substance is sometimes described as ‘whale vomit’, there’s scant evidence that it’s actually ejected from the body – from either end. Many scientists believe ambergris is released after a whale dies and decomposes, with radiocarbon dating showing that some samples were floating around in the ocean for over a thousand years before the flotsam was washed-up on shores.
Can ambergris preserve organisms? Unlike solid amber, which can protect an arthropod’s delicate appendages, ambergris only preserves hard structures: the oldestknown deposits from 1.75 million years ago contain mineralised squid beaks. As a fatty, insoluble substance, ambergris prevents genetic material from disintegrating and resists rough marine conditions.
Which whales produce ambergris? Tests have only detected DNA from the sperm whale, but dwarf and pygmy sperm whales might make ambergris, too.
For hundreds of years, humans have exploited whales for ambergris. Exploiting DNA in ambergris will now provide insights into the ecology and evolution, microbes and metabolism of whales.