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New species of dumbo octopus identified using minimally invasive techniques

BMC (BIOMED CENTRAL)

Research News

 

A new species of deep-sea dwelling dumbo octopus called Grimpoteuthis imperator sp. nov. has been described using a combination of MRI, micro-CT and minimally invasive gene analysis rather than traditional dissection methods. The findings are presented in the open access journal BMC Biology.

The single specimen, which was identified as a mature male, was named G. imperator because it was discovered in the northern part of the Emperor Seamounts, an undersea mountain ridge in the Northwest Pacific Ocean. In addition to the scientific name in Latin, the authors suggest possible common names for this new species such as Emperor dumbo, Dumbo impérial (French), and Kaiserdumbo (German).

Finned or dumbo octopods, although considered rare organisms, form a significant part of the megafauna in deep-sea habitats down to at least 7,000 m depth. Current methods used to describe new cephalopod species often require dissection to examine internal organs, which involves damage to or even partial destruction of a specimen and may thus preclude analysis of singular, endangered, rare, or otherwise valuable organisms.

Alexander Ziegler and Christina Sagorny at Rheinische Friedrich-Wilhelms-Universität Bonn, Germany combined non-invasive methods including digital photography, standardized measurements, high-field magnetic resonance imaging (MRI), and micro-computed tomography (micro-CT), with minimally-invasive tissue sampling for DNA analysis to gather morphological as well as molecular information on the specimen collected during R/V SONNE's scientific cruise SO-249 BERING. Using this novel combination of non-invasive and minimally invasive techniques allowed the authors to describe a large zoological specimen for the first time without damaging it.

The authors were able to identify details including shell and gill shape, digestive tract morphology, as well as more minute structures such as the nervous system and sensory organs, but also morphological characters so far not used in the description of octopus species, such as the shape of the systemic heart. By using micro-CT, which is more suitable than MRI for visualization of chitinous tissues, the authors were also able to build the first interactive 3D model of a cephalopod beak.

Characteristics including shell form, fin position, and arm length identified the specimen as belonging to the genus Grimpoteuthis. However, the number of suckers, half-orange-shaped gills, and details of the shell differentiate it from all previously described Grimpoteuthis species.

Alexander Ziegler said: "The MRI and micro-CT datasets we have obtained here and which are publicly available from the repository MorphoBank could be used for further analyses that would not have been possible to this extent using conventional, invasive techniques. This may allow other researchers to draw conclusions about the life style and behaviour of hard-to-observe deep sea organisms."

Notes to editor:

1. Research article:

Holistic description of new deep sea megafauna (Cephalopoda: Cirrata) using a minimally invasive approach

Ziegler and Sagorny. BMC Biology 2021

DOI: 10.1186/s12915-021-01000-9

For an embargoed copy of the research article please contact Anne Korn at BMC or visit the Springer Nature press site.

After the embargo lifts, the article will be available here:

https://bmcbiol.biomedcentral.com/articles/10.1186/s12915-021-01000-9

Please name the journal in any story you write. If you are writing for the web, please link to the article. All articles are available free of charge, according to BMC's open access policy.

2. BMC Biology is an open access journal publishing outstanding research in all areas of biology, with a publication policy that combines selection for broad interest and importance with a commitment to serving authors well.

3. A pioneer of open access publishing, BMC has an evolving portfolio of high quality peer-reviewed journals including broad interest titles such as BMC Biology and BMC Medicine, specialist journals such as Malaria Journal and Microbiome, and the BMC series. At BMC, research is always in progress. We are committed to continual innovation to better support the needs of our communities, ensuring the integrity of the research we publish, and championing the benefits of open research. BMC is part of Springer Nature, giving us greater opportunities to help authors connect and advance discoveries across the world.

First description of a new octopus species without using a scalpel

Biologists at the University of Bonn use state-of-the-art non-destructive methods to study an octopus from the deep sea

UNIVERSITY OF BONN

Research News

 

IMAGE: EXTENDS JUST OVER HALFWAY DOWN THE ARMS. THIS SUGGESTS A HABITAT CLOSE TO THE SEAFLOOR. view more 

CREDIT: © ALEXANDER ZIEGLER

An evolutionary biologist from the University of Bonn brought a new octopus species to light from depths of more than 4,000 meters in the North Pacific Ocean. The sensational discovery made waves in the media a few years ago. Researchers in Bonn have now published the species description and named the animal "Emperor dumbo" (Grimpoteuthis imperator). Just as unusual as the organism is the researchers' approach: in order to describe the new species, they did not dissect the rare creature, but instead used non-destructive imaging techniques. The results have now been published in the prestigious journal BMC Biology.

In the summer of 2016, Dr. Alexander Ziegler from the Institute of Evolutionary Biology and Ecology at the University of Bonn spent several months in the North Pacific aboard the research vessel SONNE. The crew lowered the steel basket to the seabed around 150 times in order to retrieve rocks, sediments, and living creatures. One organism in particular caused a media stir: a dumbo octopus. The animal, about 30 centimeters in size, was found in waters more than 4,000 meters deep. However, the octopus could not be recovered alive: "The deep-sea organism is not adapted to the environmental conditions of the ocean surface," Ziegler explains.

Dumbo octopuses are a group of deep-sea-dwelling octopuses that includes 45 species. The name is based on the flying elephant from the Walt Disney movie of the same name, who is made fun of because of his unusually large ears - the fins of the dumbo octopuses, which are on the sides of the head resemble these elephant ears. However, the dumbo on the research vessel SONNE differed significantly from the known octopus species. "It was clear to me straight away that we had caught something very special," the biologist reports. So Ziegler immediately photographed the unusual animal, took a small tissue sample for DNA analysis, and then preserved the octopus in formalin.

Together with his former master's student Christina Sagorny, Ziegler has now published a description of the previously unknown species. Just as unusual as the octopus was the methodology used. The animals are usually dissected by zoologists, as the internal organs are also important for the description of a new species. "However, as this octopus is very valuable, we were looking for a non-destructive method," explains the researcher.

High-field MRI instead of scalpel

The eight-armed cephalopod therefore did not end up under the scalpel, but in the high-field magnetic resonance imaging system of the German Center for Neurodegenerative Diseases (DZNE) in Bonn. This device is routinely used to image test persons' brains. Thankfully, Dr. Eberhard D. Pracht from the DZNE agreed to conduct a high-resolution scan of the dumbo octopus in 3D. As part of her master's thesis, Christina Sagorny then investigated whether high-field MRI can be used to study internal organs and other soft tissues just as well as through conventional dissection. "The quality is actually even better," Ziegler says.

One of the few exceptions: the beak and rasping tongue (radula) of the cephalopod are made of hard chitin that does not image well using MRI. The biologists therefore also consulted the micro-computed tomography system of the paleontologists at the University of Bonn. This technique showed the beak and radula razor-sharp and in 3D. "These hard part structures are an integral part of the species description of octopuses," Ziegler explains. The researchers also decoded the animal's genetic material to reconstruct the family relationships. Ziegler: "The DNA showed beyond a doubt that we were looking at a species of the genus Grimpoteuthis."

Examination of the reproductive organs revealed the dumbo octopus to be an adult male. Compared to other species of this genus, it displays several special characteristics. For example, an average of 71 suckers were detected on each arm, which the animal needs to catch prey and which reflect body size. The length of the cirri, which are small appendages on the arms that the deep-sea animals presumably use to sense their prey, also differs from species already known.

The web that stretches between the arms, with which the dumbo slowly floats down in the water column, catching worms and crustaceans as if in a bell, also only reaches just over halfway from the mouth down the arms. "The web is much longer in dumbo octopus species that mainly float freely in the water column," Ziegler says. This would indicate that the new species lives close to the seafloor, because otherwise the web would be a hindrance to movements on the bottom.

As the species-describing researchers, Sagorny and Ziegler had the privilege of naming the new species: they decided on Grimpoteuthis imperator - in English "Emperor dumbo". Background: the animal was discovered not far from Japan in an underwater mountain range whose peaks are named after Japanese emperors.

Digital copy of the organism

The combination of non-destructive methods produced a crisp digital copy of the animal. Anybody interested can download it from the online database "MorphoBank" for further research and learning purposes. The preserved octopus itself is kept in the archives of the Museum für Naturkunde in Berlin, Germany. "There, it can then still be analyzed 100 years from now, for example when more modern investigation methods or new questions arise," Ziegler explains. "Our non-destructive approach could set a precedent, especially for rare and valuable animals," said the Bonn-based evolutionary biologist.

###

Funding:

No third-party funds were used to conduct the study.

Publication: Alexander Ziegler, Christina Sagorny: Holistic description of new deep sea megafauna (Cephalopoda: Cirrata) using a minimally invasive approach, BMC Biology, DOI: https://doi.org/10.1186/s12915-021-01000-9

Video of the recovery of the emperor dumbo: https://bmcbiol.biomedcentral.com/articles/10.1186/s12915-021-01000-9

CAPTION

the Emperor dumbo (Grimpoteuthis imperator). The description of the new species also includes the internal organs, which are shown here in color in the form of an interactive 3D model.

CREDIT

© Alexander Ziegler

Quantifying the level of pollution in marinas

UNIVERSITY OF SEVILLE

Research News

IMAGE: ALEJANDRO FERNÁNDEZ-ROMERO, ONE OF THE AUTHORS OF THE STUDY view more 

CREDIT: UNIVERSIDAD DE SEVILLA

An interdisciplinary group of Spanish scientists, bringing together biologists and chemists from the Universities of Seville, Huelva, the Autonomous University of Madrid and the Institute of Marine Sciences of Andalusia of the CSIC in Cadiz, have just published the results of their pioneering research studying the management of marinas. The group of scientists, led by the US professor José Manuel Guerra García, studied in detail the sediments in Andalusia's marinas and has proposed a new index, the MEPI (Marinas Environmental Pollution Index) to quantify the level of contamination in these ports.

There has been a proliferation of marinas in recent years, in Spain, other Mediterranean countries and in the rest of the world. Marinas are highly modified ecosystems that have a great impact on marine biota. On the one hand, they alter the area's hydrodynamism, damming ecosystem in and tending to concentrate pollutants (heavy metals, hydrocarbons, etc.). In addition, recreational boats can be responsible for transporting invasive species from one area to another, attached to the boats' hulls.

"It is essential to regulate these marinas. To this end, authorities need scientists to provide tools to manage these ecosystems in the best possible way. Ideally, we should try to build more environmentally sustainable ports and aim to establish minimum ecological quality levels enabling us to identify marinas that make efforts to control environmental conditions and make their waters and sediments higher quality than elsewhere", explains Professor Guerra.

Specifically, the MEPI index is based on parameters such as hydrocarbons, heavy metals, faecal coliforms, nitrogen, phosphorus, sulphur and biocides such as Irgarol, which are used as a base in the manufacture of the antifouling paints applied to prevent organisms from adhering to recreational boats. The MEPI index was developed using national and international sediment quality recommendations and reference values and ranges proposed by legislation in different countries around the world. Together with the new index, the authors have applied a simple and complete ecological analysis method to determine a port's quality in a holistic and integrated way, taking into account both chemical and biological parameters. For this purpose their models used not only the MEPI, but also values relating to the diversity of organisms living in the sediments, biotic indices measuring the quality of the seabed based on these organisms, and biotic pollution indices based on the number and abundance of invasive species. Thus, communities of organisms living on the bottom of the ports were studied, including both macrofauna (those larger than 0.5 mm such crustaceans, molluscs, annelid worms and echinoderms mainly), and meiofauna (smaller than 0.5 mm, mainly copepods and nematodes).

"These small animals that live in ports are the best 'whistleblowers' of port quality, making the role of biologists crucial in understanding how these ecosystems function. Depending on the species we find, we can tell how polluted a port has become," adds the researcher.

The study's innovative approach enabled the integration of both environmental parameters, where the role of chemists was key, and biological parameters as part of a holistic model. Based on all the indicators used, the researchers have proposed a total scoring system (the sum of each parameter's partial score) that allows the ecological quality status of a port to be established using a scale that is easy for authorities to interpret and in line with the European water quality directives. On this basis, colour-coded quality levels can then be established for each marina, ranging from red (very poor quality) to blue (excellent quality).

Thanks to this excellent work, in which the researcher Alejandro Fernández-Romero also participated, and based on the study of the marinas along the Andalusian coast, simple and integrated environmental quality assessment tools are now available for application in any marina anywhere in the world. The information provided can be key, for example, to awarding distinctions, such as the blue flag, to marinas that meet environmental quality requirements. Similarly, Dr. Guerra carried out several studies during his doctoral thesis which demonstrated that the creation of tunnels or hydrodynamic channels in ports, or ports designed with double entrances, such as the port of Ceuta, allow greater water renewal, increase oxygen levels and favour higher levels of biological diversity.

"We must try to move towards 'eco-sustainable' designs that minimise the negative impact of creating or remodelling a port. In this sense, both biologists and chemists can contribute invaluable input for engineers, ensuring they opt for coastal infrastructure designs that are more ecological and less harmful to marine flora and fauna", concludes José Manuel Guerra.

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Climate change impacts conservation sites across the Americas

DURHAM UNIVERSITY

Research News

 

IMAGE: AN INCA JAY AT OTUN QUIMBAYA, COLOMBIA view more 

CREDIT: PROFESSOR STEPHEN WILLIS

A continental-scale network of conservation sites is likely to remain effective under future climate change scenarios, despite a predicted shift in key species distributions.

New research, led by Durham University and published in the journal Frontiers in Ecology and Evolution, investigates the impacts of potential climate change scenarios on the network of Important Bird and Biodiversity Areas (IBAs) across the Caribbean, and Central and South America.

The research was carried out in collaboration with Senckenberg Biodiversity and Climate Research Centre, BirdLife International and the National Audubon Society.

IBAs are sites identified as being internationally important for the conservation of bird populations, with over 13,000 sites identified across 200 countries in the last 40 years. Many are covered by formal protected areas, while others are conserved by community-managed reserves or indigenous lands.

Two of the principal responses of species to recent climate change events are changes in range and abundance, leading to a global reshuffling of populations.

Range changes may cause species to disappear from areas they occupy, whilst providing them with opportunities to colonise new sites.

This redistribution could affect the ability of international site networks (including protected areas) to conserve species. Therefore, identifying which sites will continue to provide suitable conditions and which are likely to become unsuitable is important for effective conservation planning as our planet continues to warm.

Estimating the impact of climate change on species' distributions, and the consequences for networks of sites identified to conserve them, can help to inform conservation strategies to ensure that these networks remain effective.

The research modelled the effects of different scenarios of climate change on the wider network.

It determined that, for 73 percent of the 939 species of conservation concern for which IBAs have been identified, more than half of the IBAs in which they currently occur were projected to remain climatically suitable and, for 90 per cent of species, at least a quarter of sites remain suitable.

These results suggest that the network will remain robust under climate change. What is concerning however, is that seven percent of the species of conservation concern are projected to have no suitable climate in the IBAs currently identified for them."

Professor Stephen Willis, Director of Research in the Durham University Department of Biosciences said "The Caribbean and Central and South American region supports about 40% of all the bird species of the world, so this network is vital for a large proportion of the world's birds.

To develop realistic predictions of future changes, we not only considered where suitable climate will occur for species in future but also the likelihood of species dispersing to newly suitable sites.

This information is helping to identify potential management strategies across the IBA network."

Stuart Butchart, Chief Scientist at BirdLife International and a co-author on the study, said: "These results highlight how critical it is to effectively conserve the network of Important Bird and Biodiversity Areas across the Americas in order to help safeguard birds in the region under climate change.

"Despite projections of significant shifts in the distributions of individual species, the network as a whole will continue to play a key role in future conservation efforts."

Aurelio Ramos, Senior VP, Audubon International Alliances Program said "Applying this science to secure and strengthen IBAs in the Americas is essential to support the future of birds and people. Audubon, BirdLife International, American Bird Conservancy and REDLAC have partnered in the Americas on a project to strengthen protection of Climate secure IBAs identified in the research called Conserva Aves"

Alke Voskamp of the Senckenberg Biodiversity and Climate Research Centre added "The results of this study highlight the importance of a network-wide perspective when making conservation management decisions for individual sites when planning for climate change."

The researchers note that designating protected areas to safeguard biodiversity is a cornerstone of species conservation and the importance of considering local environmental management decisions and their impacts on wider, global conservation networks has never been more relevant.

CAPTION

Itai National Park, Brazil

CREDIT

Professor Stephen Wil

CAPTION

Plovercrest Hummingbird

CREDIT

Professor Stephen Willis

USAGE RESTRICTIONS

Source information

Site-Based Conservation of Terrestrial Bird Species in the Caribbean and Central and South America Under Climate Change: http://journal.frontiersin.org/article/10.3389/fevo.2021.625432/full?&utm_source=Email_to_authors_&utm_medium=Email&utm_content=T1_11.5e1_author&utm_campaign=Email_publication&field=&journalName=Frontiers_in_Ecology_and_Evolution&id=625432

PHOTOS

Available through this Dropbox link: https://www.dropbox.com/sh/kg46ynagz2cmzxw/AAD4MWlDBA_tT3UZ97dBWVRSa?dl=0

Credit - Professor Stephen Willis

Useful web links

Professor Stephen Willis' profile: https://www.dur.ac.uk/research/directory/staff/?id=1048

Dr. Stuart Butchart's profile: https://www.zoo.cam.ac.uk/directory/stuart-butchart

Alke Voskamp's profile: https://www.linkedin.com/in/alkevoskamp?originalSubdomain=de

About Durham University

Durham University is a globally outstanding centre of teaching and research based in historic Durham City in the UK.

We are a collegiate university committed to inspiring our people to do outstanding things at Durham and in the world.

We conduct boundary-breaking research that improves lives globally and we are ranked as a world top 100 university with an international reputation in research and education (QS World University Rankings 2021).

We are a member of the Russell Group of leading research-intensive UK universities and we are consistently ranked as a top 10 university in national league tables (Times and Sunday Times Good University Guide, Guardian University Guide and The Complete University Guide).

For more information about Durham University visit: http://www.durham.ac.uk/about/

END OF MEDIA RELEASE: Issued by Durham University Marketing and Communications Office - http://www.durham.ac.uk/news

Red Sea is no longer a baby ocean

Hidden structures reveal 13 million years of seafloor spreading

HELMHOLTZ CENTRE FOR OCEAN RESEARCH KIEL (GEOMAR)

Research News

 

IMAGE: BATHYMETRIC CHART OF A PART OF THE RED SEA. view more 

CREDIT: GEOMAR

It is 2,250 kilometers long, but only 355 kilometers wide at its widest point - on a world map, the Red Sea hardly resembles an ocean. But this is deceptive. A new, albeit still narrow, ocean basin is actually forming between Africa and the Arabian Peninsula. Exactly how young it is and whether it can really be compared with other young oceans in Earth's history has been a matter of dispute in the geosciences for decades. The problem is that the newly formed oceanic crust along the narrow, north-south aligned rift is widely buried under a thick blanket of salt and sediments. This complicates direct investigations.

In the international journal Nature Communications, scientists from GEOMAR Helmholtz Centre for Ocean Research Kiel, King Abdullah University for Science and Technology in Thuwal (Saudi Arabia) and the University of Iceland have now published a study that makes a good case for the Red Sea being quite mature and having an almost classical oceanic evolution. "Using a combination of different methods, we can show for the first time that the structures in the Red Sea are typical for a young but already fully developed ocean basin." says Dr. Nico Augustin from GEOMAR, lead author of the study.

In addition to information from high-resolution seafloor maps and chemical investigations of rock samples, the team primarily used gravity and earthquake data to develop a new tectonic model of the Red Sea basin. Gravity anomalies have already helped to detect hidden seafloor structures such as rift axes, transform faults and deep-sea mountains in other regions, for example in the Gulf of Mexico, the Labrador Sea or the Andaman Sea.

The authors of the current study compared gravity patterns of the Red Sea axis with comparable mid-ocean ridges and found more similarities than differences. For example, they identified positive gravity anomalies running perpendicular to the rift axis, which are caused by variations in crustal thickness running along the axis. "These so-called 'off-axis segmentation trails' are very typical features of oceanic crust originating from magmatically more active, thicker and thus, heavier areas along the axis. However, this observation is new for the Red Sea," says Dr. Nico Augustin.

Bathymetric maps as well as earthquake data also support the idea of an almost continuous rift valley throughout the Red Sea basin. This is also confirmed by geochemical analyses of rock samples from the few areas that are not overlain by salt masses. "All the samples we have from the Red Sea rift have geochemical fingerprints of normal oceanic crust," says Dr. Froukje van der Zwan, co-author of the study.

With this new analysis of gravity and earthquake data, the team constrains the onset of ocean expansion in the Red Sea to about 13 million years ago. "That's more than twice the generally accepted age," Dr. Augustin says. That means the Red Sea is no longer a baby ocean, but a young adult with a structure similar to the young southern Atlantic some 120 million years ago.

The model now presented is, of course, still being debated in the scientific community, says the lead author, "but it is the most straightforward interpretation of what we observe in the Red Sea. Many details in salt- and sediment-covered areas that were previously difficult to explain suddenly make sense with our model." While it has thus been able to answer some questions about the Red Sea, the model also raises many new ones that inspire further research in the Red Sea from a whole new scientific perspective.

HERBALISM

Inhibitory effect of strawberry geranium on inflammatory response in skin keratinocytes

SHINSHU UNIVERSITY

Research News

 

IMAGE: STRAWBERRY GERANIUM (SAXIFRAGA STOLONIFERA), CALLED YUKINOSHITA IN JAPANESE. view more 

CREDIT: MARUZEN PHARMACEUTICAL CO., LTD

Strawberry geranium (Saxifraga stolonifera) has been used in Japan as a herbal medicine to treat wounds and swelling, and continues to be an ingredient in food and cosmetics. Pharmacological studies have shown that extracts of strawberry geranium have antioxidant and antitumor activities. However, the anti-inflammatory effect of strawberry geranium on the skin had not been well characterized.

This study, first-authored by associate professor Takeshi Kawahara of the Institute of Agriculture, Shinshu University for a joint research project with Maruzen Pharmaceutical Co., Ltd. succeeded in obtaining results which showed that the suppression of excessive immune response mediated by Toll-like receptor 2 (TLR2) to infectious microorganisms of skin keratinocytes which indicates strawberry geranium, called yukinoshita in Japanese can be a means of resolving routine infectious dermatitis.

Antibiotics against microorganisms and steroid-like components that suppress inflammation are generally used to control dermatitis, but the emergence of resistant bacteria and side effects due to chronic use are making them less desirable. Strawberry geranium provides a means to locally control inflammation on the body by provoking a limited immune response.

Yukinoshita, which means below the snow in Japanese, is a highly safe plant substance with a proven track record that has been used for centuries as foods and in cosmetics. Saxifraga stolonifera is also known as a crude drug and though its anti-inflammatory effect has been known, the detailed mechanism of action had not been elucidated. It is expected to be applied as an anti-inflammatory material based on the expression-suppressing effect of the TLR2 molecule clarified by this study.

Based on the results of this research, the research group is planning to conduct an efficacy test for people with mild acne. This approach has a different mechanism of action from conventional anti-inflammatory agents, but if useful results are obtained, it is expected that strawberry geranium can be widely used as an anti-inflammatory substance.

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For more information on the study, please read: Inhibitory effect of strawberry geranium (Saxifraga stolonifera) on Toll-like receptor 2-mediated inflammatory response in human skin keratinocytes

CAPTION

Strawberry geranium (Saxifraga stolonifera), called yukinoshita in Japanese.

CREDIT

Maruzen Pharmaceutical Co., Ltd

CAPTION

Strawberry geranium (Saxifraga stolonifera), called yukinoshita in Japanese.

CREDIT

US asbestos sites made risky by some remediation strategies

STANFORD UNIVERSITY

Research News

 

The Environmental Protection Agency (EPA) largely remedies Superfund sites containing asbestos by capping them with soil to lock the buried toxin in place. But new research suggests that this may actually increase the likelihood of human exposure to the cancer-causing mineral.

"People have this idea that asbestos is all covered up and taken care of," said Jane Willenbring, who is an associate professor of geological sciences at Stanford University's School of Earth, Energy & Environmental Sciences (Stanford Earth). "But this is still a lingering legacy pollutant and might be dribbling out pollution, little by little."

Willenbring has published several studies about asbestos behavior and, most recently, turned her attention to the lack of information about how asbestos may move through the soils where it is stored. Through lab experiments with asbestos fibers, which were detailed in a paper published Jan. 27 in the Journal of Hazardous Materials Letters, she and colleagues determined that the soil's organic material actually enables the asbestos to move through the ground and potentially into nearby water supplies.

They found that dissolved organic matter changes the electric charge on asbestos particles and makes them less sticky, thereby enabling them to move faster through soil. The work disproves the prevailing theory that asbestos fibers cannot easily move through soil - an assumption that has been made in part because of the mineral's hair-like shape.

"It's surprising that even though these little fibers are so long, because their shortest diameter is small enough, they can wind their way through these soil pores," said Willenbring, who is senior author on the study.

Inhalation of asbestos increases the risk of developing lung disease and lung cancer, and exposure could occur through irrigation, taking showers, using humidifiers or other unfiltered sources that disperse water into the air.

A legacy pollutant

Asbestos is a naturally occurring mineral that mainly forms in the subsurface, at the boundary of Earth's oceanic and continental crusts. For much of the 20th century, it was revered as a miracle building material for its high heat capacity and insulation properties, and mining and production boomed worldwide. Following widespread evidence of its link to cancer, including a rare and aggressive form called mesothelioma, production of asbestos in the U.S. declined dramatically starting in the 1970s.

In addition to thinking that the shape of the fibers would inhibit transport, the scientific community has been influenced by a 1977 EPA report that minimized the threat of asbestos moving through soil. Since then, new findings about the role of colloids - microscopic particles that remain dispersed within solutions rather than settling to the bottom - have led researchers to challenge the assumption that asbestos stays fixed in soil.

"Now we can show that exactly the thing that they do, which is add manure or other organic sludge to the asbestos piles that creates the production of dissolved organic matter, is exactly what causes the liberation of asbestos," Willenbring said. "It's actually facilitating the transport of asbestos fibers."

In some ways, the team's breakthrough about asbestos is not surprising because it aligns so closely with recent findings about the transport of colloids in soil, Willenbring said. But she was stunned by the scale of the problem: Millions of people in the U.S. are living near thousands of sites contaminated with asbestos.

At least 16 Superfund sites contain asbestos and areas where the mineral naturally occurs can also pose a risk.

Improving remediation

As part of the lab experiments, Willenbring and her team sampled soil from the BoRit Superfund Site in Ambler, Pennsylvania before it was capped in 2008. The waste dump is located next to a reservoir, as well as a stream that feeds water to the city of Philadelphia.

However, there is a silver lining to the team's discovery.

"Not all types of dissolved organic matter have the same effect on asbestos mobility," said lead study author Sanjay Mohanty, an assistant professor at UCLA's Civil and Environmental Engineering who collaborated with Willenbring on the experiments. "Thus, by identifying the types that have the worst effect, the remediation design could exclude those organic amendments."

As part of the remediation strategy, some sites include vegetation planted on top of the soil to prevent erosion. Willenbring's ongoing research involves figuring out how fungal-vegetation associations may be able to extract iron and make the asbestos fibers less toxic to people.

"It's not just inflammation in the lungs that's a problem - there's a process by which iron contained in the asbestos fiber is actually responsible for causing DNA damage, which can lead to cancer or mesothelioma," Willenbring said.

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The study was co-authored by a researcher from Midwestern University.

The research was supported by the University of Pennsylvania's SRP Center Grant (P42 ES027320), "Asbestos fate, exposure, remediation, and adverse health effects" from the National Institute of Environmental Health Sciences (NIEHS).