Washing our hands with soap and water is something we do every day. We are well aware of miniscule organisms that can cause massive infection if left unchecked, but it hasn't always been so.
Up to the 19th century, doctors and surgeons did not see the relevance of cleaning their hands, tools or clothes.
They would use the same blades from patient to patient without cleaning them, and wear the same coat day in and day out.
They took pride in the surgical stink of their coats and saw the stains of past surgeries as evidence of experience and knowledge. Pus was thought to be a sign of healing, and doctors believed infections were caused by miasma or bad air.
British surgeon Joseph Lister challenged these thoughts. He was concerned about the high rates of infection and death post-surgery and sought to reduce the risk to patients facing the surgeon's knife. His work would revolutionise the field.
He was inspired by the microbiology work of Louis Pasteur. In 1865 Pasteur published a paper stating that food spoiled because of the presence of micro-organisms, and proposed three ways to remove these microscopic threats through heat (now known as pasteurisation), filtration and chemical exposure. Lister could not use filtration on his patients and his experiments with heat were unsuccessful, so he looked to chemical alternatives.
Lister considered the use of carbolic acid, found in coal tar, after learning that the substance was spread on fields that had been irrigated with sewage waste. It removed the smell so appeared to have a beneficial aspect, and did not cause illness to the livestock on the fields. He believed, therefore, it would not cause harm to humans.
Lister began using carbolic acid while working at the Glasgow Royal Infirmary and noticed a drastic reduction in the rate of infection and death in his patients. He instructed his staff to routinely wash their hands with a 5 per cent carbolic acid solution before and after surgery, and to apply the solution to their surgical equipment, wound sites and any dressings that were used. Assistants were even sprayed with it before entering the operating theatre.
He published his results in 1867 but they were not immediately accepted. Some surgeons used the incorrect concentration of carbolic acid in their solutions and reported no change in infection rates, skin irritation in their patients or even carbolic poisoning.
Many had a difficult time understanding germ theory, but attitudes changed as germs were further investigated and understanding grew. The medical field realised it was best to prevent infection from entering the surgical site, and aseptic surgery became the norm with carbolic acid the first widely used antiseptic.
Carbolic acid, also known as phenol, became a wonder chemical that battled invisible enemies and began being incorporated in many aspects of daily life, including personal products. Carbolic soap was a popular medicinal soap that claimed to kill germs, prevent infection, clean wounds and cure skin irritations. It was also put in many 19th century toothpastes and powders, claiming to kill germs, prevent tooth decay and sweeten the breath with the sweet-tarry smell of carbolic acid.
• Sandi Black is the archivist at Whanganui Regional Museum.