A group of students from the University of Reykjavik have created a shampoo made from cow urine.
The six scientists said they drew from an Icelandic tradition of women pouring the waste product into water to wash their hair.
Co-creator Anton Reynir Hafdisarson said: "Despite the critics, some people will think it exciting and want to give it a try. Icelandic history tells us that girls used to mix urine into their washing water to clean and beautify their hair."
Anton Reynir Hafdisarson brewing up a batch
"We hope there will be more fans than there are people who simply think the idea is disgusting," he added.
Cow urine contains ammonia, which is an active ingredient in many modern shampoos. The "Q Shampoo" also contains sunflower and coconut oils to mask the smell.
"Some people think there is a slight whiff of urine in the soap," Hafdisarson added. "But that might just be because they know what's in the product. We think it is not noticeable."
The scientist claims to wash his hair with the product every day and hopes to sell it on the international market.
"The product is 100 per cent organic with no artificial ingredients or harmful by-products," he says.