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Courtesy of the Oriental Institute of the University of Chicago

Their goddess Ishtar is linked to Venus, Aphrodite, Freya, and Kali, but more explicitly than her Indo-European counterparts, she is the goddess of both procreation and death. The ancient Babylonians are well known for their expertise in astronomy and mathematics, but I suggest that they understood a lot more about chemistry than is commonly recognized. My reasoning—specious, I admit—is that Ishtar had as her symbol an eight-pointed star. I believe that the Mesopotamians knew the atomic number of oxygen (though not the difference between s and p orbitals), and realized the importance of oxygen chemistry to the molecular origin of life and death. What they missed out on, and what the Teutonic nomads clearly understood, was the crucial role of transition metals. In the Norse pantheon, Freya had a twin, Frey, who was connected with the mineral wealth of the Earth. Indeed, the element vanadium reflects this, for it is named after the twins’ collective designation “Vanadis”.

I have long been fascinated by that moment in evolution when microbes learned to handle oxygen. Until then, their spread had been limited, for the oxygen they produced as a byproduct of their growth was toxic to themselves and others. Furthermore, they had to process polymers anaerobically, limiting the polymers’ usefulness for storing energy. And then a bright bacterium hit on the idea of fixing oxygen with iron- or copper-containing polymers. It was a pity that they didn’t have patents back then, for he or she, the ancestor of us all, would have been a very rich bug.

Our love–hate relationship with element number eight continues to this day. Oncologists have shown that the radicals it produces in the body are a major cause of cancer, and that the antioxidants in fruit and vegetables are essential to our health.

Transition metal–oxygen chemistry got me into trouble as a child. I was working away in the kitchen with potassium permanganate from my chemistry set and whatever I could find—hydrogen peroxide, I think—when my test tube started to froth over, spilling corrosive purple gunk over the work surface. I was still trying to clean up the mess when Mum came in. I narrowly escaped a thrashing, but my test tubes and I were banished to the cold and damp of the shed.

I had more fun with manganese later, when I began my career. I was trying to catalyze the oxidation of acrylic fibers, the first stage in making carbon fibers. Virtually any transition metal helped, but manganese gave the reaction such a kick that the fibers burst into flames. Other chemists I know have had similar problems with manganese and what it can do to synthetic fibers. I understand that a major detergent manufacturer recently had to withdraw a new product, launched at great expense, when it was discovered that a manganese-based additive caused garments of a certain hue to dissolve in the wash.

On the positive side, I wouldn’t be where I am today were it not for the influence that oxygen and those brightly colored salts from the middle of the periodic table can have on polymerizations. My current employers owe their existence to the chance discovery, in the 1950s, of an adhesive that wouldn’t set up if there was oxygen about, and which would only set up in the presence of iron and copper in the lower oxidation states. Not much of an adhesive, you might think, but if you paint it onto a bolt, then screw the bolt into a nut, eliminating air, the stuff cures rapidly, securing the assembly. Much of modern engineering depends on this unheralded piece of serendipity, which made Loctite a great deal of money.

To return to Ishtar: I think we chemists should make her our goddess of oxidation, for without it, life forms would be much simpler and the termination of complex ones less common. She needs a new symbol, though—one that reflects her role as an Earth mother, the twin circles of Life and Death, and the diradical nature of the oxygen molecule.

David Birkett is a senior scientist in the Irish chemical industry.