# Timothy Leighton

Timothy Grant Leighton (born 16 October 1963) is a British scientist. He is the Executive General Director and Inventor-in-Chief of Sloan Water Technology Ltd., (a company founded on his inventions). This followed a career in academia, in which he still holds positions. Magdalene College, Cambridge University, elected him to an Honorary Fellowship. University College London elected him to an Honorary Professorship. The University of Southampton elected him to be Emeritus Professor of Ultrasonics and Underwater Acoustics after 10 years at Cambridge University and over 30 years at Southampton University. Three national academies made him an Academician (Fellow of the Royal Society, Fellow of the Academy of Medical Sciences, Fellow of the Royal Academy of Engineering). Trained in physics and theoretical physics, he works across physical, medical, biological, social and ocean sciences, fluid dynamics and engineering. He completed the monograph The Acoustic Bubble in 1992 at the age of 28, and was awarded a personal chair at the age of 35. He has authored over 500 publications. The recipient of 8 international medals, he was awarded a doctorate in 1988, and a higher doctorate in 2019, from the University of Cambridge.

## Education

He was educated at Heversham Grammar School, Cumbria and Magdalene College, Cambridge where he took the Natural Sciences Tripos and was awarded a double first class Bachelor of Arts degree with honours in physics and theoretical Physics in 1985, obtaining a PhD in 1988 at the Cavendish Laboratory, University of Cambridge. Following his PhD, he was awarded senior and advanced research fellowships at Magdalene College, Cambridge funded by the Engineering and Physical Sciences Research Council (EPSRC).

## Early career

He joined the Institute of Sound and Vibration Research (ISVR) at the University of Southampton in 1992 as a lecturer in underwater acoustics, and completed the monograph The Acoustic Bubble in the same year. He was awarded a personal chair at the age of 35.

## Research

He founded and led two research organisations with international membership (Global-NAMRIP and HEFUA). He also founded and led the Ultrasonics and Underwater Acoustics Group at the University of Southampton. He is the Executive General Director and Inventor-in-Chief of Sloan Water Technology Ltd., and talks extensively to schoolchildren, the public, and on radio and video.
His research covers medical, humanitarian and environmental sciences, beginning with the fundamental mathematics and ending with engineering applications. His research interests cover acoustical oceanography, antimicrobial resistance, biomedical ultrasound, carbon capture and storage, climate change, decontamination, hospital acquired infections, infection prevention, wound healing, antimicrobial resistance, pandemic preparedness, marine zoology, fluid dynamics, cavitation, ultrasound and underwater acoustics. Working in such fields as cold water cleaning, sound in space, ultrasound in air, BiaPSS, TWIPR, and passive acoustic lithortripsy monitoring, he emphasized the need to push pioneering research into game-changing technology, as opposed to incremental research that is published but falls short of societal benefit:
   ...We need to work with rigour, imagination, and wonder, unconstrained by the artificial boundaries set in place by discipline names, or the history of projects in which we have previously worked, or the tendency of sponsors to believe they can pick winners, or above all by the belief that we must jump to solutions when we have not yet perceived the real problem. Then, when we eventually do find a solution, we must have the will to push it through all the way to help others, and not simply publish in the expectation that someone will finish the job for us.
He worked as part of the team investigating whether man-made sounds can adversely affect benthic species (marine life that inhabits the seabed). Such species have been overlooked in studies on how man-made sounds affect whales, dolphins and fish: benthic species find it far harder to relocate away from adverse sounds than do these other more mobile species. Furthermore, benthic species play a key role in the health of the marine sediment, turning it over and preventing it stagnating, and are key to the health of coastal marine environments.
With other teams he developed methods to assess which fish species are most at-risk from man-made noise in the oceans, and quantified such noise from shipping. Turning the problem on its head, he worked with other teams on how to use sound as 'underwater acoustic scarecrows' to guide fish away from regions of man-made danger. These might occurs, for example, where industry exacts cooling water from rivers used as migration paths of endangered species (the young of European eel are slim enough for the flow to pull them through grills placed over such extraction points). He developed the theory for predicting the barometric trauma experienced by fish when passing through hydroelectric facility>, a major cause of environmental and economic hardship. Fish that move between critical habitats fragmented by river infrastructure, injury and mortality is common among those that transit via hazardous routes, with one in five (22.3%) that pass through hydropower turbines killed.

### NAMRIP and Global-NAMRIP

In 2015, Leighton founded the Global Network for AntiMicrobial Resistance and Infection Prevention (Global-NAMRIP),. He led it, substantially funding it from his inventions from 2019-2024. Upon his retirement in 2024, it closed. A key mission of Global-NAMRIP that he instituted was to organise dozens of conferences, all without ever charging delegates and attendees (and even funding travel for delegates from sub-Saharan Africa), in order to allow people who had not worked across disciplines before to meet up and grow new collaborations, stimulating new areas of research. Global-NAMRIP emphasized the need to collaborate with end-users to ensure the right problems were tackled, and addressed with solutions that the end-users could implement for patients and public health.

### Health Effects of Ultrasound in Air

In 2015, Leighton founded the research group Health Effects of Ultrasound in Air (HEFUA). His aim was to map the increasing use of ultrasound in public places, and to investigate whether or not this increase is having adverse effects on some humans (following an investigation which revealed that the use of ultrasound in public places is increasing, and that guidelines were inadequate prior to the 2016 report).
His 2016 report that first raised the issues was, in the first 2 years, downloaded over 20,000 times from the Royal Society website, leading to requests for a follow-up, a journal special issue, and numerous conference sessions worldwide as the importance of this topic was realised. Whilst high-powered airborne ultrasound in the lab could cause burning and possibly alterations in hearing acuity, the lower level airborne ultrasound found in public places could cause headaches, tinnitus, nausea, migraine, inability to concentrate or perform a task, distraction and annoyance. His logic-based argument that the lower frequency limit for ultrasound should be 17.8 kHz, as opposed to the traditional one of 20 kHz, rapidly became adopted by specialist scientists. Scientists, engineers and the public around the world are now logging the location and type of device that emits ultrasound. His research allowed schoolteachers to use his published techniques to identify how ultrasound in classrooms was preventing students from working. This was particularly problematic because teachers, janitorial staff, inspectors and some of the students in the class, were unaffected and could not hear the ultrasound that was so affecting a subset of the class. Leighton became an acknowledged world expert on such public exposures, and on the claims of 'sonic attacks' on US Embassy staff in Cuba and China. His expertise on the effect on humans of ultrasound in air provided the scientific basis that was cited by Giles Watling MP (Clacton, Conservative) in the Motion for leave to bring in a Bill (Standing Order No. 23) on "Anti-loitering Devices (Regulation)" (17 July 2018 Volume 645, 2.06 pm).
In 2018, Leighton published an editorial that identified flaws in the way the statistical analysis was conducted on those identified as victims of the claimed attacks, which set up the tests in such a way that even unexposed people would, for the most part, be identified as suffering adverse health effects from the exposure. In 2023, the US Office of the Director of National Intelligence (ODNI) agreed with this assessment, stating ‘that initial medical studies that led experts to believe that the AHIs [anomalous health incidents] “represented a novel medical syndrome or consistent pattern of injuries” suffered from “methodological limitations”’. Consequently, it reported that an inter-agency intelligence analysis from 7 agencies concluded that 5 considered it ‘very unlikely’ (one judging it ‘unlikely’, and one abstaining from an opinion) that a foreign adversary had deployed a weapon in the attacks.
He currently serves on the Scientific Expert Group of the International Commission on Non-Ionizing Radiation Protection (who in 2024 published a report he advocated for and co-authored) and the International Standards Organisation to support appropriate protections for people (particularly children) exposed to airborne ultrasound.

### Extraterrestrial acoustics

Since the mid-2000s, Leighton attempted to increase interest in using sound to explore other planets by predicting the soundscapes of other worlds and how these could best be exploited using acoustic devices, led to devices for planetaria to use when teaching about other worlds, and showed how careful calculation was needed to avoid mistakes when using acoustic sensors on other worlds. With Professor Petculescu of the University of Louisiana at Lafayette, Leighton co-hosted three special sessions and a journal special issue of the Acoustical Society of America on acoustics in extraterrestrial environments (in 2007, 2008, 2016 and 2023). Leighton was invited to the International Space Science Institute to support the Mars Perseverance and Ingenuity missions.

### Marine mammal acoustics

Leighton's explanation of how humpback whales use sound when feeding in bubble nets is now a staple explanation on whale tour boats. He explained how dolphins can echolocate while producing bubble nets to hunt, a process that should blind their sonar.

## Inventions
### Medical and healthcare

Leighton invented systems for:
* detecting bone disease (including osteoporosis).
* monitoring the efficiency of kidney stone therapy (an invention that won the 2008 ‘Medical & Healthcare’ award from ‘The Engineer’ with key collaborator: Guy's and St Thomas' NHS Foundation Trust).
* solutions for needle-free injectors for migraine sufferers (over 1 million sold).
and assisted the Institute of Cancer Research with technology for tumour therapy monitoring (2010).
Two billion people have been scanned in the womb under the guidelines he helped co-author for the World Federation for Ultrasound in Medicine and Biology guidelines for foetal ultrasonic scanning.
He served on the Government of the United Kingdom's Working Group of the Advisory Committee on Dangerous Pathogens Transmissible Spongiform Encephalopathies Sub Group and advised the Health Protection Agency, the International Commission on Non-Ionizing Radiation Protection and the International Standards Organization (ISO) on the safety of ultrasound.
Other medical and healthcare inventions and breakthroughs are listed below under Sloan Water Technology Ltd., Global-NAMRIP and HEFUA.

### Humanitarian

Leighton invented:
* radar for the detection of buried explosives, hidden bugging devices, and for the location of buried catastrophe victims (in avalanches, mudslides, collapsed buildings etc.)
* the world's only sonar system capable of detecting objects in bubbly water (key, for example, to protecting services, cargo and aid shipping in conflict zones). - mine detection is often an ongoing problem long after conflict has reduced and civilians return to former conflict zones (key collaborator: Paul White)
* a number of systems for detecting objects buried in the seabed
and, in collaboration with the National Oceanography Centre, one sold by Kongsberg for archaeological and civil engineering purposes. Various collaborations are looking at ways of providing clean water from waste in Low- and Middle-Income Countries, including mentorships of young entrepreneurs in Africa.

### Environmental and Safety

Leighton:
* devised and conducted the experiment that revealed that the amount of carbon dioxide dissolving into the oceans was much greater than the values previously used in predicting climate change and ocean acidification;
* invented technology used by environmental agencies and oil and gas companies to monitor for undersea gas leaks from pipelines, and from methane seeps, by their acoustic emissions.
* devised the theory and methodology by which sonar could be used to monitor and quantify gas leaks from carbon capture and storage facilities in the seabed. This was later included as part of large-scale multinational trials on the North Sea seabed and elsewhere to assess leakage
* systems assess the amount of methane in the seabed. This is important to assess the potential for leaks from these reserves into the sea and (eventually) the atmosphere (in the seabed, there is probably more carbon trapped in methane than there is in all other forms of conventional fossil fuel, yet as a greenhouse gas methane is 20 times more potent per molecule than carbon dioxide, so assessing how much is in the seabed, and how much leaks into the atmosphere, is a key task).
* devised theory and methodology for measuring key parameters in the transfer of atmospheric gas between atmosphere and ocean, that was later included in large-scale multi-national trials This is important for climate change modelling, because over 1000 million tonnes of atmospheric carbon transfers each year between atmosphere and ocean.
* Inventions assist safety in the world's most powerful pulsed spallation neutron source ($1.3 billion) at the Oak Ridge National Laboratory in the United States.

### Sloan Water Technology Ltd.

In the late 1980s, Leighton discovered a new ultrasonic signal that he identified as due to surface waves on the walls of gas bubbles in liquids. Multidisciplinary research in the following 12 parallel streams of work turned this discovery into Sloan Water Technology Ltd. Because Leighton's research was fundamental, in addition to leading to Sloan Water Technology Ltd., he generated impact by following this fundamental work into other applications.

## Awards and honours
### Medals

* the 2017 Clifford Paterson Lecture and Medal of the Royal Society (video of Lecture here)
* the 2014 Rayleigh Medal of the Institute of Acoustics
* the 2013 Helmholtz-Rayleigh Interdisciplinary Silver Medal of the Acoustical Society of America
* the 2009 R W B Stephens Medal of the Institute of Acoustics
* the 2006 Paterson Medal of the Institute of Physics
* the inaugural 2004 Early Career Medal and Award of the International Commission for Acoustics
* the 2002 Tyndall Medal of the Institute of Acoustics
* the 1994 A. B. Wood Medal of the Institute of Acoustics
The citation of the 2006 Paterson Medal of the Institute of Physics states that:
   Timothy Leighton's contribution is outstanding in both breadth and depth. He is an acknowledged world leader in four fields... He has delivered over 70 pioneering advances, from devices now used in hospitals to the world's first count of bubbles in the surf zone (crucial to our understanding of atmosphere-ocean gas flux, coastal erosion and the optimisation of military sonar). Behind these advances lies rigorous physics.

### Awards

* 2019 Doctor of Science, University of Cambridge
* 2018 Royal Society's Lord Leonard and Lady Estelle Wolfson Foundation Translation Award for the StarHealer
* the 2014 'Best new product of the year' award for StarStream
* the 2012 Institute of Chemical Engineering Award for Water Management and Supply
* the 2011 Royal Society Brian Mercer Award for Innovation
* the 2008 'Medical & Healthcare' award from 'The Engineer'
* the inaugural 2001 International Medwin Prize for Acoustical Oceanography from the Acoustical Society of America

### Fellowships

Leighton is an Academician of three National Academies. He was elected a Fellow of the Royal Society (FRS) in 2014. His nomination reads:
   Timothy Leighton is distinguished for his research on the acoustical physics of bubbles, especially their nonlinear behaviour; for his inventions and discoveries including bubble measurements in the surf zone, pipelines and methane seeps; for shock wave lithotripsy monitoring, disease detection in cancellous bone and needle free injection; for sonar systems that overcome bubble masking and numerous industrial applications. His seminal monograph The Acoustic Bubble has become the primary reference on bubble physical acoustics.
In 2018 he was elected to Fellowship of the Academy of Medical Sciences, the citation reading for 'harnessing the physical sciences for the benefit of patients' as:
   an outstanding academic inventor whose leadership in acoustical physics of bubbles has led to the development of new medical devices and procedures. His research has dominated the field of acoustic bubbles since the appearance of his monograph in 1994, ‘The Acoustic Bubble’, which was published at the age of 29. In this, he laid out the mathematical foundation upon which much of the recent cutting edge research on ultrasonic contrast agents, drug delivery, and focused ultrasound surgery has been based. He has exceptional ability to deliver engineering solutions to real world problems from conceptualisation to product development embracing an advanced practical knowledge of IP strategy.
Leighton was elected a Fellow of the Royal Academy of Engineering (FREng) in 2012 for his services to Engineering and society. He was elected a Fellow of the Institute of Physics (FInstP) in 2000, Fellowship of Institute of Acoustics in 1999, Fellowship of the Acoustical Society of America in 1998, and Fellowship of the Cambridge Philosophical Society in 1988. He is a Visiting Fellow of the Institute of Advanced Studies of Loughborough University.
In 2018 the International Institute of Acoustics and Vibration (IIAV), of which he had not been a member, undertook a change to its Bylaws, and vote of all IIAV members, to create new rank of Distinguished Fellow. It is the highest rank for individual IIAV members of this international body, and Professor Leighton was the recipient in its inaugural year.

## Outreach, TV and radio work

Leighton has developed and conducted multiply-award-winning outreach activities to the public, and to encourage of young men and women to engage, and possibly follow careers in, science and engineering, with school visits, science fairs, exhibits, games, and appearances on TV and radio. His public engagement work regarding his invention, “The most dangerous game in the world”, which he designed to communicate with the public on the issue of superbugs and how they can protect themselves and society, was mentioned by Steve Brine MP, the Under-Secretary of State for Health on 16 November 2017. The IMDb and "Who's Who" have collated entries for Professor Leighton. In his 2014 book 'Sonic Wonderland', the broadcaster Trevor Cox described Professor Leighton as 'a middle-aged Harry Potter'.

## Charity work

Leighton was a driving force in the foundation of Solent Concert orchestra and, barring a period of 6 months, has been Chairperson since its foundation. The orchestra performs 3 concerts per year, raising funds for numerous charities, tending to support smaller charities that do not benefit from national fundraising campaigns.