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
Global threat to primates concerns us all
19.01.2017 | Deutsches Primatenzentrum GmbH - Leibniz-Institut für Primatenforschung
Reducing household waste with less energy
18.01.2017 | FIZ Karlsruhe – Leibniz-Institut für Informationsinfrastruktur GmbH
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences