Researchers at the University of Edinburgh, led by Professor Stephen Wallace, have developed a method to transform "fatbergs"—the massive sewer blockages caused by congealed fats, oils, and non-biodegradable waste—into valuable, pine-scented oils that could one day be used in perfumes, according to the New York Post.
Fatbergs are accumulations of fat, oil, wet wipes, and other waste that build up in sewage systems, causing major backups. "Fatbergs occur when people flush solid waste like wet wipes and condoms down the toilet, which then combine with grease and oils to create giant, foul-smelling blobs that can cause major backups," Vice News reported.
Traditionally, after being removed, fatbergs are sent to landfills for incineration, contributing to greenhouse gas emissions and groundwater contamination, as noted by Asianet Newsable. Disposal of fatbergs is costly; Thames Water spends over $22 million annually on clearing fatbergs.
Professor Wallace's approach involves collecting samples from a company that specializes in excavating fatbergs from sewers. He then processes them with specially modified bacteria that consume the fats and oils in sewage. "We have proven that disposal costs can not only be offset but turned into profit by creating a useful product," Wallace explained, as reported by BBC News.
The first step in the process is to sterilize the fatberg material using high-temperature steam in a boiler to destroy microbes. After sterilization, Wallace adds specially modified bacteria to the remaining fatberg. These bacteria have been altered with DNA from plants to produce a chemical with a pine resin smell, as detailed by Asianet Newsable.
As the bacteria consume the fatberg, they multiply and release fresh-smelling compounds, reducing odors from sewage systems while producing economically valuable products, helping to offset the cost of clearing the sewers.
Professor Wallace believes that this project has the "potential to be a transformative solution to the climate crisis and to creating a more sustainable future for future generations," according to Vice News. He envisions a future where engineered bacteria are introduced into sewage treatment plants to break down fatbergs and create "sweet-smelling chemicals."
The University of Edinburgh team's work is not yet commercially viable due to the small quantities of fragrance produced, the New York Post noted. "Don't expect to see 'eau de fatberg' at your local department store anytime soon," Wallace said. Nevertheless, his lab is working with UK partners to explore the commercial potential of their research.
There are still ethical concerns about releasing genetically engineered bacteria into the environment. Scientists and industrialists agree that without public trust, the engineering biology industry will struggle. To win public trust, advocates of engineering biology must be open and honest about the risks, according to BBC News.
In addition to the challenges of commercialization, the UK is at risk of losing its lead in engineering biology to countries like the US and Korea due to insufficient investment and follow-through. "Although the UK is leading in developing the technology, it now needs to take the next step: scaling up to production," Professor Wallace said.
Fatbergs have been a problem in urban sewer systems. The largest fatberg ever discovered, found in 2017, measured 820 feet long and weighed 286,000 pounds (130 tonnes), making it one of the largest on record, as reported by Komsomolskaya Pravda.
By turning waste into valuable resources, Professor Wallace's method offers a more sustainable alternative, reducing the environmental footprint of sewer systems. "We are turning waste into something valuable," he stated.
The article was written with the assistance of a news analysis system.