In the current issue of the journal Environmental Science & Technology, they reveal that introduction of the compound tributyltin (TBT) as a biocide in boat paint in the 1960s resulted in a dramatic and sudden loss of aquatic vegetation from most of the 50 or so Norfolk Broads lakes.
At the time, scientists pointed the finger at contamination from sewage works and fertiliser run-off from farmland, despite suggestions from the local community that the burgeoning leisure boating industry might be to blame.
Though the use of TBT was banned in freshwater systems in the UK in 1987, the researchers say 40 years on from TBT’s introduction the fragile ecosystem remains shattered despite expensive attempts to restore it.
Dr Carl Sayer, of the UCL Environmental Change Research Centre, who co-led the study, says: “For too long TBT has been neglected as a driver of environmental destruction in freshwater wetlands and even though it is no longer in use in UK inland waterways, TBT contamination and its negative effects are still being reported all over the world.
“Real concerns have been raised about TBT derived from industrial and ship breaking activities in several major river systems including the Ganges, Brahmaputra and Yangtze – all of which are connected to shallow lakes. In the case of the Yangtze, the linked shallow lakes are some of the largest in the world and, like the Broads, have experienced problems with plant loss on a large scale.”
TBT was originally designed for use on the hulls of large ocean-going ships to reduce the build-up of barnacles. Since the 1970s it has been linked to a host of negative effects in the marine environment including mutations in shellfish. An aggressive marketing programme in the 1960s saw its use fashionably worldwide on much smaller craft both in the oceans and within inland waterways.
“TBT is extremely toxic and highly persistent in the environment, earning it the controversial title as the most toxic substance ever introduced deliberately by man into the aquatic environment,” explains Dr Sayer.
“In freshwaters, once TBT is released from an antifouling coating it is rapidly absorbed by bacteria and algae, and eventually works its way up the food chain. Within a short period of time after the paint’s introduction to the Broads, it knocked out many of the small invertebrates which are a part of the life support system for water plants – turning the waters of the Broads green with algae.”
To investigate levels of TBT in the Broads the researchers took sediment cores from two lakes, one close to the centre of the boating industry and the other half a kilometre away. Results show an abrupt decline in plant and invertebrate populations at the precise time that a strong TBT signature was detected.
“The irony of the tale is that the paint was designed to stop barnacles attaching to boats – which you don’t get in freshwater. By simply lifting boats out of the water once a year and using a bit of elbow grease, one of Britain’s areas of outstanding natural beauty might still be intact rather than on the long road to recovery.”
The study was funded by English Nature, the Broads Authority, the Department of Environment, Food and Rural Affairs (DEFRA), and the Natural Environment Research Council (NERC).
Judith Moore | alfa
Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide
Malaysia's unique freshwater mussels in danger
27.09.2016 | The University of Nottingham Malaysia Campus
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences