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Shades of L’Aquila: Italian Geochemists avoid Huge Miscarriage of Justice

Shades of L’Aquila: Italian Geochemists avoid Huge Miscarriage of Justice

On rare occasions I hear about a story that must be told. This story is one of those and I feel that it deserves attention from the broader geoscience community.

We have all heard of the L’Aquila verdict against the Italian seismologists concerning the devastating earthquake in 2009. If you haven’t, read these articles by Chris Rowan. At the time the guilty verdict was handed down the entire geoscience community felt stunned that such a thing could have happened. The prevailing attitude was that it should not be possible to accuse and convict scientists for practicing responsible science. However, the old adage goes: those who don’t learn from history are doomed to repeat it. This brings me to the topic of this post, which was a very near miss by the Italian justice system against four geochemists from the University of Siena.

I originally heard of the story at Goldschmidt 2013 in Florence during a presentation by Dr. Luigi Marini and I wrote a short note about it in my daily summary of the conference on this blog. After the conference I asked Dr. Marini for more information as I felt the details of this case needed to be heard. I recently heard back from Dr. Marini that the case has now been resolved in favour of the geochemists and I am now free to write about their story on this blog.

The story begins, in December 2002, with several geochemists from the University of Siena being asked by the Italian Ministry of Defense to perform a geochemical-environmental study in the Sardinian Poligono Interforze Salto di Quirra (PISQ), comprising the two firing ranges of Perdasdefogu and Capo San Lorenzo.

Numerous different military activities were carried out at the PISQ since July 1st, 1956, including: (i) launch of rockets (ii) release of bombs from airplanes and helicopters (iii) use of artillery, from land and ships (iv) tests of pressurized pipes.

According to media and some local associations, Depleted-Uranium (DU) ammunitions were used in the PISQ and caused the so-called “Quirra Syndrome”. The “Quirra Syndrome” refers to an apparently greater-than-normal incidence of illnesses in the local population and military personnel that served at the Quirra base. It occurs mainly as cancers and natal genetic malformations. However, the “Quirra Syndrome”  has not been confirmed by the Italian national health authority, the Istituto Superiore di Sanità (ISS).

So one of the goals of the Siena geochemists was to determine if DU had been used in tests.

quirra

Google screen capture of Sardinia. Quirra, which is the subject of the study, is the red pointed location.

On the face of it the task seems simple enough: analyze soil, plants and water for U and its isotopic ratio and other potential contaminants from the munitions range (of which are there many). However, the complicating factor in all of this is that fact that adjacent to the firing range is an abandoned mine site called Baccu Locci. The Baccu Locci mine contains significant quantities of arsenopyrite and galena, which are arsenic and lead bearing minerals. Both arsenic and lead are known to have detrimental effects on the environment and humans. So the real question then becomes which is it? Mine waste or DU or other military contaminants? Furthermore, historical records from PISQ say no DU was used in the region, however, lots of other munitions with their own suite of toxic components may have been. Therefore, isolating a single cause of the possible impacts on the environment and humans becomes very complex indeed.

Taking a quick step back let’s review some of the basic science in question here.

What is DU?

DU stands for depleted uranium and it was the central contaminant discussed in the case. Uranium comes in many isotopes but the two most common are 238U and 235U. Most uranium found in nature is ~99.2% 238U and ~0.7% 235U. However, most nuclear reactors use fuel that is enriched in the isotope 235U to around 20% as it is more easily fissionable than natural uranium. A by-product of the enrichment process is uranium that is missing its 235U and has a larger proportion of 238U than is normally found in nature. This uranium is said to be depleted as it has had the 235U removed. This DU can then be used for other applications outside of the nuclear industry as it has the rare property of being one of the most dense metals known. This property makes it used in a wide variety of industries but particularly in military applications as a tip for missiles, armour penetrating bullets and other types of scary munitions. DU munitions have been used in Desert Storm, Bosnia, Kosovo and recently in Iraq and Afghanistan and at numerous munitions test sites around the world.

Gunner's mates inspect linked belts of Mark 149 Mod 2 20mm ammunition before loading it into the magazine of a Mark 16 Phalanx close-in weapons system aboard the battleship USS MISSOURI

US Navy personnel inspect linked belts of DU tipped ammunition (Wikimedia Commons)

The problem is that when DU munitions are used the uranium is blown into millions of tiny particulates that can spread on the wind and introduce widespread contamination to the environment. DU contamination is a serious issue. The radiological risks of DU are low in comparison to many other radionuclides due the long half life of 238U and the low energy alpha particles that it emits although they cannot be ignored altogether if the concentration of DU is high. The far greater risk from DU, however, is the high toxicity of the uranium metal itself as it attacks the kidneys in people similar to metals such as lead and cadmium. DU exposure has been linked to cancer, birth defects and other diseases for people living in contaminated areas and diseases afflicting veterans of the Gulf War as it acts in concert with other contaminants from these former war zones.

Acid Mine Drainage

Acid mine drainage is a phenomenon that many geochemists work with every day. In brief it occurs when sulphide minerals like galena (PbS), pyrite (FeS2) or arsenopyrite (FeAsS) are left exposed to open atmosphere and precipitation. What happens is a chemical oxidation reaction in which the sulphide minerals such as galena (PbS), pyrite (FeS) or arsenopyrite (FeAsS) react with air and water to release sulphuric acid and free metal ions. In the case of galena you get lead or arsenic from arsenopyrite.

Rio_tinto_river_CarolStoker_NASA_Ames_Research_Center

An extreme example of acid mine drainage from a mine in Spain. (Wikimedia Commons)

Indeed, Frau et. al. (2009), found significant evidence of contamination from Baccu Locci Mine wastes in streams leading from the region, which is a tributary of the larger Quirra River that flows through the village into the Tyrrhenian Sea. The paper found elevated concentrations of lead, cadmium, zinc and arsenic near mine wastes, however, concentrations decreased downstream due to dilution and precipitation of insoluble lead-arsenic minerals. These heavy metals could have detrimental effect on the health of local residents.

OK, so back to the case.

The researchers from the University of Siena did what was asked of them and analyzed over 1500 samples for a variety of contaminants, including the 235U/238U ratio (on selected samples), totalling 25,000 results. Their findings were that there was no contamination from DU in the region and that the 235U/238U was on par with the natural 235U/238U ratio. However, they did find elevated levels of arsenic and lead around the former mine site and in catchments draining it.

Distribution map of uranium concentrations in top-soils of the two firing ranges of Perdasdefogu and Capo San Lorenzo and nearby areas (from the Siena University report, 2004).

Distribution map of uranium concentrations in top-soils of the two firing ranges of Perdasdefogu and Capo San Lorenzo and nearby areas (from the Siena University report, 2004).

Histogram (left) and statistical parameters of uranium concentrations in the top-soils of the two firing ranges of Perdasdefogu and Capo San Lorenzo and nearby areas (from the Siena University report, 2004).

Histogram (left) and statistical parameters of uranium concentrations in the top-soils of the two firing ranges of Perdasdefogu and Capo San Lorenzo and nearby areas (from the Siena University report, 2004).

Furthermore, one of the supporters of the Quirra syndrome conducted health related modelling using a code called HOTSPOT and found that in order to cause the anomalous number of cancers observed in Quirra between 80-140 tons of DU had to have been used, which is an absolutely huge amount (Zucchetti 2005).

These results met with extreme opposition from the local prosecutor who acted on the advice of a nuclear physicist from the University of Brescia who felt that geochemistry was not the proper way to investigate this problem and that the University of Siena scientists were hiding something. Indeed, the physicist felt that thorium was the true culprit and that geochemists were not qualified to analyze for radioactive contamination. (I obviously take great exception to this notion as a radioisotope geochemist and user of an accelerator mass spectrometer). Anyway, the geochemists were charged with two crimes in connection with their results:

  1. Not stating the danger of anomalous concentrations of thorium present at the firing ranges.
  2. Using knowledge the geochemists had gained from their previous work on DU in Kosovo to select methods that prevented them from detecting depleted uranium at PISQ.

In answer to the first charge the geochemists provided results of Th analyses for soils in the Quirra region. These show that there are no Th anomalies present in the soil. Therefore, the notion that Th is somehow the hidden, skulking culprit in all of this is simply not the case.

In answer to the second charge that the geochemists knowingly sampled in such a way as to conceal the detection of DU one simply has to look at the aims of the two investigations. In Kosovo the Siena scientists were sampling a small area with known DU contamination and a documented history of DU use. This makes it much simpler to find DU and sample for it. On the other hand, in Quirra, the use of DU has not been confirmed and the study area was far larger. This means that instead of a small scale, targeted sampling campaign the appropriate investigation tactic was a broad, large scale sampling effort that attempted to give an overview of contamination in the region. If DU was found a more detailed look could then be performed in that specific site. However, since no DU was found no more sampling was necessary.

Ultimately, the court appointed an independent expert to examine the results of the University of Siena geochemists in the light of these two charges before proceeding to trial. The expert found that the methods used by the University of Siena researchers were completely reasonable and that there was no evidence of a Th or DU anomaly. Thus on July 11, 2014 the case against the geochemists was dismissed and they were completely exonerated as the victims of unjustified persecution.

This entire episode was certainly very hard for the scientists from the University of Siena. In addition, it should also serve as a cautionary tale for the larger scientific community. This story can only breed hesitation and reticence on the part of scientists to participate in such efforts to help the public. Such aggression on the part of the local prosecutor is a warning to other scientists to stay away from the Quirra region and avoid the potential liability that comes with it. On a larger scale, this trial warns scientists outside of Italy that participating in issues involving human health, or ones that are emotionally charged, can be a bad thing. This lesson is not one that helps people. By telling scientists that if we don’t like your results we’ll attack you personally only turns us away and ultimately enhances ignorance and short sighted decision making. It will be a sad day indeed when I or others turn down a project because of the liability risk involved when we could actually be helping the public interest by practicing responsible science. I hope that this is not what Italy or other nations are coming to.

Thanks for reading! I would also like to acknowledge Dr. Luigi Marini for keeping me updated over the past several months as the trial progressed and his permission to blog about such an important issue.

References

Cristaldi M, Foschi C, Szpunar G, Brini C, Marinelli F, Triolo L. Toxic emissions from a military test site in the territory of Sardinia, Italy. Int J Environ Res Public Health. 2013;10(4):1631–46.

Frau F, Ardau C, Fanfani L. Environmental geochemistry and mineralogy of lead at the old mine area of Baccu Locci (south-east Sardinia, Italy). J Geochemical Explor. 2009;100(2-3):105–15.

Marini L. – Goldschmidt Abstracts 2013. Mineral Mag. 2013;77(5):1661–817. Available from: http://goldschmidt.info/2013/abstracts/finalPDFs/1685.pdf

Zucchetti M. Environmental Pollution and Health Effects in the Quirra Area, Sardinia Island (Italy) and the Depleted Uranium Case. J Environ Prot Ecol. 2006; 7(1): 82-92

 

 

I’m on TV!!

I’m on TV!!

About a year ago I was asked to appear as a guest on a kids television show about rocks and minerals called Finding Stuff Out. I was asked to come an talk about rocks, minerals, geology in general and how I got interested in geology. The show is for 8-10 year olds and it is truly fantastic! It has a really interesting format where kids actually ask questions and the host, Harrison, answers them with the help of experts (me), goes to places to find the answers or does experiments. In the end the show concludes with an answer to the question that started it all. In the case of my episode it was about diamonds.

I was fortunate enough to be involved in a significant amount of the show including the “gold” panning challenge and the final wrap up at the end of the show, which has a bit of a humorous slant to it!

This was my first experience filming anything let alone a full out TV show so I was not sure what to expect when I arrived at the studio in Montreal. The first thing I was given was a terrific lunch, so that was a nice way to start the afternoon off.

2013-10-07 14.58.58

Next I was shown to the set, which is incredible. See the pics below. It is truly amazing what the set designers and prop people can accomplish and I was pretty impressed. I was then given a script that had a few talking points. The actual dialog and what I say in the video is me speaking in my own words and basically making it up on the spot. This was pretty difficult so we would usually do a couple of takes as I polished my delivery a bit. All in all the 10 minutes of video that you see below took about 5-6 hours to shoot. The challenge section was by far the longest as we had to keep re-doing sections of the panning.

2013-10-07 18.13.31

There is also a lot of people watching as we would shoot each scene including sound people, script editors, prop people, cameramen…..and more. This was kind of a weird feeling since it felt like I was performing some sort of live show but I was supposed to be speaking directly to Harrison. I had to keep reminding myself not to worry about everyone else. Harrison, who looks younger than he actually is, was also fantastic. The guy is crazy talented and is a big part of making the show so interesting and popular. I had a great day shooting the episode and hopefully it won’t be my last experience with this sort of thing! Maybe I’ll do a video blog here or two when I finally finish my PhD!??

2013-10-07 18.11.46

I’ve edited the video above so it only includes parts of the show that I was in. There is lots more.

Hope you enjoy it!!

GeoPoll #3 – What got you interested in geology?

After a bit of an opinion hiatus I am back with the third geopoll. Every day I go to work at a university department filled with geologists. All of us are tackling different questions, but in the beginning we all started at the same place. Namely, not knowing anything about geoscience. In my conversations with colleagues over the years it appears that there is no single way to get into geology. We all entered the field from different avenues. For example, some people found it through a first year course, others, like me, started out as mineral and fossil collectors when they were kids or teenagers and still others only started in geology for graduate school and have a degree in chemistry or physics. Furthermore, geoscientists and professional geologists do not have a monopoly on enjoying and studying the Earth. In fact, geology is one of the few sciences that it is easy for anyone to practice at home and there are many amateur geologists out there that this poll also applies to as well. As I say, there is no single access point, but the passion unites us all. So, I have to ask: what got you interested in geology?

A gratuitous photo of the mineral Stibnite (SbS) from China. It is currently for sale here…if you happen to have a spare $23,500.

The serious side of this poll is perhaps it will hopefully inform how we can be better at geoscience outreach. If we have a better idea of how the current group of geologists got hooked perhaps we can target our outreach to a particular audience in the hopes of attracting a new generation of geoscientists. Or, as I suspect is the case, many people got hooked in university. Is this too late? Should we be trying to get geology courses into high school and elementary school curricula like chemistry and physics in order to get young people interested or at least educated about the earth? Perhaps us geoscience communicators need to work on attracting a younger audience?

Finally it is tough to think of good poll questions so if you have a good idea for a question(s) please post in the comments! As usual, click the view results button on the bottom of the poll to see how things are shaking out.

The Search for Ithaca

This post unifies two of my absolutely favourite topics: geology and classical Greek history. I have always had a soft spot for the classics. In fact, when I started my undergrad I was planning on doing a double major of geology and classics. I decided to focus on geology, but I have not lost my love of ancient civilizations particularly the ancient Greeks and Romans.

File:Head Odysseus MAR Sperlonga.jpg

Odysseus (Source: Wikipedia)

Most of us are familiar with the story of the Odyssey, but I’ll recap it here briefly. The Odyssey is the tale of Kind Odysseus’s journey back from Troy to his home island of Ithaca. Odysseus, despite being a pretty shrewd guy, angers the god Poseidon who condemns him to wander the ocean for decades before he can go home. During this time Odysseus experiences many wild adventures in is quest to return home to his wife, Penelope and his son, Telemachos. Eventually, Odysseus returns home, but just in time to prevent his kingdom falling into rival hands. It is a classic good guy triumphs over evil tale and one of the best classical poems ever written. Homer obviously took substantial creative licence in the poem, as was customary at the time, however many of the places he mentions are real, as are the people such as Agamemnon, Menelaus, Troy, Mycenae, Sparta, etc. However, there has always been a question…where is Ithaca?? Indeed, Ithaca was missing. The home of the principle character in the poem was nowhere to be found and this just doesn’t jive with the accurate nature of rest of the poem.

This is a question that had baffled classical scholars for decades. At first, many believed that Homer just made up Ithaca since at that time Troy was believed to be fictional as well. However, once Troy was discovered it no longer made sense to think that Ithaca was made up and therefore, it must be some place amongst the Greek islands.

The passage in the Odyssey that describes the location of Ithaca is as follows:

 εἴμ’ Ὀδυσεὺς Λαερτιάδης, ὃς πᾶσι δόλοισιν

ἀνθρώποισι μέλω, καί μευ κλέος οὐρανὸν ἵκει.

ναιετάω δ’ Ἰθάκην ἐυδείελον: ἐν δ’ ὄρος αὐτῇ

Νήριτον εἰνοσίφυλλον, ἀριπρεπές: ἀμφὶ δὲ νῆσοι

πολλαὶ ναιετάουσι μάλα σχεδὸν ἀλλήλῃσι,

Δουλίχιόν τε Σάμη τε καὶ ὑλήεσσα Ζάκυνθος.

αὐτὴ δὲ χθαμαλὴ πανυπερτάτη εἰν ἁλὶ κεῖται

πρὸς ζόφον, αἱ δέ τ’ ἄνευθε πρὸς ἠῶ τ’ ἠέλιόν τε,

 

I am Odysseus, Laertes’ son, world-famed

For stratagems: my name has reached the heavens.

Bright Ithaca is my home: it has a mountain,

Leaf-quivering Neriton, far visible.

Around are many islands, close to each other,

Doulichion and Same and wooded Zacynthos.

Ithaca itself lies low, furthest to sea

Towards dusk; the rest, apart, face dawn and sun.

 

So there you have it in beautiful Homeric Greek. The location of Ithaca…it is the westernmost of the Greek islands, which today is Cephalonia, formerly known as Sake, and not Ithaca. As for the current Greek island called Ithaca it in no way meets the description of Homer’s Ithaca and therefore it cannot be the same island, unless Homer was trying to play a massive joke on us all or did not understand basic geography, neither of which is very likely. So where did ancient Ithaca go?

Over the past few years a new theory has emerged to answer this question. In short the idea is that the thin isthmus of land between Paliki and the rest of Cephalonia was at one point underwater separating the two places and resulting in two islands. Indeed, there is classical text to back up such and idea. Strabo, the renowned ancient geographer wrote “where the island is narrowest it forms an isthmus so low-lying that it is often submerged from sea to sea.” If we trust Strabo, this means that during classical times there were actually two islands that are now one. Perhaps, westernmost Paliki was Ithaca during Homer’s time and the current island called Ithaca was another island was Doulichion. However, how can we prove that this idea is more than just an interesting theory?

Elevation map of Cephalonia. The white test is the current names and the yellow text is the name in Homer’s time. (Source: Odysseus Unbound)

Well, to answer this question we must turn to geology…we had to get there sometime.

The geological investigation of Stabo’s channel, now known as the Thinia valley, is being carried out by John Underhill, a professor of seismic and sequence stratigraphy in the University of Edinburgh department of geosciences. The geological evidence that Strabo’s channel existed is outlined in a paper by Dr. Underhill published in Nature Geoscience and is freely available online. However, I’ll give a brief outline of the evidence here.

In order to prove that Paliki was once an island the geology must show that the Thinia valley was once under water. However, the problem is that the elevation of the Thinia valley is 180m above sea level…and sea level certainly has not changed 180m is only 3000 years!!! However, there are other geologic features that can account for some of the uplift. The Eastern side of the Thinia valley is divided by a large thrust fault known as the Aenos Thrust, which is an extremely active fault to this day. Indeed, the last major earthquake on Cephalonia was a 7.2 magnitude in August 1953. The seismicity is generated by the collision of the Eurasian plate with the African plate. However, the earthquakes, while they cause substantial uplift did not occur often enough or have enough displacement to result in over 180m of uplift since the time of Homer. Therefore, another mechanism is needed to fill in the valley and raise it to 180m. Mapping of the island and the valley revealed a possible solution to this problem. The mapping revealed the occurrence of several large landslides and rockfalls in the valley. In fact, large blocks from the valley walls are easily observable within the valley. These massive landslides and rockfalls were caused by the earthquakes and storms and a lot of material fell from the steep valley walls into the valley.

A resitivity survey of the Thinia valley. The blue is Cretaceous bedrock, red is water, and the green and yellow are unconsolidated sediments. (Source: Odysseus Unbound)

 To further prove the existence of Strabo’s channel, however, direct evidence of marine sediments must be observed underneath all of the landslide fill. In order to do this Underhill’s team drilled numerous boreholes around the valley and found many places where there was indeed marine sediment. In addition to drilling they also conducted geophysical surveys in order to map the subsurface geology of the valley in greater detail, which would allow them to map the channel and prove that it actually separated Paliki from the rest of Cephalonia. The geophysical techniques allowed them to determine the amount of fill in the valley from landslides, the depth to bedrock and the bedrock contours. Further surveys also revealed that there were drainage features in the sediment of the embayments on either side of the valley which shows that water flowed into the sea through the valley. Combining the boreholes, and the geophysical mapping all of the evidence points to the fact that Strabo’s channel did exist 2000-3000 years ago and that since that time uplift from earthquakes, landslides and rockfalls has filled in the channel and joined Paliki (Ithaca) to the rest of the Cephalonia concealing Ithaca from us!!!

Thanks for reading and please feel free to post any questions or comments!

References:

Odysseus Unbound: http://www.odysseus-unbound.org/

Underhill, J. (2009). Relocating Odysseus’ homeland Nature Geoscience, 2 (7), 455-458 DOI: 10.1038/ngeo562

Note: This is a repost from my pre-EGU blog location with minor updates. It was originally posted in June 2012.

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