Team:TU Delft-Leiden/Human Practices/stakeholders

Discussions with stakeholders

Visit to BioDetection Systems (BDS)

To learn more about the commercial development and application of biosensors, we visited Amsterdam-based biosensor company BioDetection Systems (BDS). Here we met with the Chief Scientific Officer, Mr. Van Der Burg. With him, we discussed the activities of BDS, our project Electrace and the biosensor industry.

The main focus of BDS is their sensing system CALUX. A range of CALUX systems exist, which all work according to a mechanism in which the compound to be detected binds to an intracellular receptor. This complex subsequently binds to a promoter in front of a luciferase gene. The luciferase which is then formed emits light and is in that way used to measure the compound of interest. Compounds which can be detected with CALUX include dioxins and several hormones.

The CALUX system is mainly applied to detect environmental and food contaminations which might be harmful for humans. “We aim to stay close to the physiology of our subject, so in this case this means that we have to use eukaryotic cells, in our case rat cells,” Van Der Burg tells. The use of eukaryotic cells however presents some problems. “For multicellular eukaryotes, there is a big step between contact with the contamination and uptake by a cell, which we have to model and simulate in our experiments. In bacteria you don’t have this problem. Next to that, eukaryotes are less robust and more complex than bacterial cells.” Upon asking why they did not work with bacteria, Van Der Burg tells us: “We are developing a bacterial version of CALUX, but only for usage in areas where bacterial physiology is important, such as soil contamination or antibiotic detection.”

The activities of BDS mainly consist of measuring samples sent by other organizations whit their CALUX system and selling licenses and training to use the system. Their customers include pharmaceutical companies, food companies and (governmental) organizations involved in environmental issues. “We have customers from all over the world. We are currently working on a project in Vietnam to detect dioxins. The concentration of these compounds in Vietnam is far above the health limits as a result of spraying with dioxin-contaminated defoliants.”

Upon being asked about innovations in BDS, Van Der Burg tells us: “We are currently mainly focused on optimizing our CALUX system. We simplify and automate the process of doing assays using our CALUX cells. Although we do not really focus on the detection of novel compounds with new pathways, we are currently trying developing a dioxin sensor for our project in Vietnam. We do this by searching for dioxin receptors which might have arisen in species living in contaminated areas.” However, this is not their usual approach in developing new sensor systems, which consist of extensive literature study and making use of toxicological research.

When we came to discussing Electrace, Van Der Burg reacted very enthusiastic. “Alternative read-outs are very interesting. For light and fluorescence assays you need lots of equipment and devious procedures. For us, this is not really a problem since we do our measurements in the lab, but for a device like yours, which is to be applied in the field, is a really ‘nice trick’.” Also, our plan to create single-use, disposable paper microfluidics strips fascinated him: “That is very interesting; a disposable device is really the thing you need. What would make it even better is if you don’t have to cultivate your bacteria anymore. These costs a lot of time, and maybe even more important, a lot of money.” We further discussed possible (commercial) application of our Electrace system. “Even when a handheld device shows to be unfeasible, there is a lot of potential for you to develop your project in a kit-like setting. This is much easier to sell than a license!”

We told Van Der Burg that we had some concerns about the speed of our system. He told us not to worry about that too much: “Our systems have a response time between 4 and 24 hours. If you really want a fast reaction you should use the translocation of tagged proteins, but this is at the expense of your accuracy.” Furthermore, he gave us some valuable advice: “The specialty of BDS is the measurement of complex mixtures, which is really important for real world applications. If your reporter responds to TNT in a distilled water solution, that is nice, but you should try if it is also possible to sense it in the kind of sample that you will use. In your case this will mean adding TNT to ground water and test it.”

Visit to the Kampfmittelräumdienst Rheinland-Pfalz

We visited the KampfmittelräumdienstRheinland-Pfalz (Bomb disposal team Rhineland-Palatinate) in Koblenz in Germany. Their work consists of the defusal and disposal of unexploded ordnance found in the German Bundesland Rheinland-Pfalz. We met with the head of the organization, Mr. Horst Lenz, with whom we discussed the search and disposal of unexploded ordnance and the possible role the TNT-sensing module of Electrace could play in that.

In Germany, still a lot of unexploded ordnance, mostly remnants from the second world war, is found. When a area of land is developed into a construction site, contractors have the possibility to screen the area for the possible presence of explosives. This screening was formerly done by the Kampfmittelräumdienst, but as of July 1st 2014, this part of their activities has been cut, a fact Mr. Lenz did not seem too sad about. Not very surprising, since this screening mostly consist of the tediously painstaking study of old photos taken by military planes. Nowadays, this screening is done by the private companies. “It is big business.” Mr. Lenz mentioned. “Private companies will ask between €2.500,- and €10.000,- for the screening of a single construction site, which comprises just doing historical review and taking a look on air photographs.”

Mr. Lenz showed us a large number of the photographs they have used for bomb screening purposes. The images were obtained from the British Air Force. Lenz: “After an air read, they flew over the area to take pictures and investigate if they had done there work right.” The images, which were of surprisingly high quality taking into account that they had been taken seventy years ago, showed parts of Germany just after being bombarded, displaying impact craters and destroyed buildings. In these pictures, one has to search for small dots indicating unexploded bombs. It is nearly impossible to deduce the presence or absence of bombs from these pictures with an acceptable degree of certainty. Lenz mentioned he felt “like a shaman hovering with his hands over the pictures to pick up signals” when he was searching for bombs on these pictures.

When it is suspected that a certain area contains bombs, the Kampfmittelräumdienst goes over there to thoroughly search the area for bombs with the use of a magnetometer. “Magnetometers sense changes in field lines of the earth’s magnetic field due to the metal in the bomb. A larger bomb has more influence on the magnetic field, but depth, position and shape also matter.” When a signal is picked up, the metal object has to be dug up. The signal often does not match with what is found: “Sometimes you expect a hand grenade, and you find a 250 pound bomb!” However most of the times a suspicious signal just comes from an iron bar or something like that.

Yet, the use of a magnetometer pose several difficulties. Altough, they can detect signals up to a depth of approximately 5 meters., much of the bombs lay at depths of around 10-15 meters and therefore cannot be found in this way. Lenz: “Although I’m not really convinced of the number, it is said that 30% of the bombs is missed by magnetometer searches.” “Current methods are not that satisfying that I can go to sleep well. Words like ‘maybe’ and ‘possibly’ are not in use by EOD specialists, because it is a matter of life and death.”

When a bomb is located, it has to be dug up. This is not without danger: “Some time ago, in our area of operation, more precisely in Ludwigshafen, a 500 pound bomb was hit with a drill, leading to the deflagration of the charge, which lifted the 80 t drilling device about 50 cm into the air. The machine operator was injured by glass shards. In Euskirchen (which is in Nordrhein-Westfalen, so another part of Germany and not in the area of operation), an excavator operator was killed by the deflagration of a 4000 pound bomb. In both cases, no employees of the Kmrd were involved.” When a bomb is excavated, in most cases the fuse is removed on site. Only in very special cases the bomb has to be detonated. The defused bombs are brought to a company where they are sawn open and where the explosive compounds are burned.<.p>

But why is bomb disposal necessary? “When bombs are in a forest or a field, they don’t pose a threat. But at a building site, in a city, they are a real danger when if they are hit.” Another danger is posed by spontaneously exploding bombs. “Under the influence of humidity and time, chemicals of the detonation mechanism can react with the metal of the bomb casing, which can cause spontaneous detonation.” A special type of bomb is particularly susceptible to spontaneous detonation. These are bombs designed to not explode on impact, but up to 144 hours afterwards. These were mostly used in WWII on industrial areas like the Ruhr Area. On impact, an ampoule filled with acetone is broken, which slowly degrades a piece of celluloid which holds a needle in place. This needle will hit the detonation mechanism when released, causing the explosion. However, this often has not worked as planned, and the bombs remain unexploded, with the risk of the needle coming off and causing detonating at a random moment.

Besides discussing the work of Mr. Lenz, we also discussed the TNT-sensing module of our project. Since land mines are not a real issue anymore in Europe (except from former Yugoslavia) and therefore not in the field of expertise of Mr. Lenz, we mostly discussed the detection of unexploded bombs. This kind of bombs is hermetically closed to keep water out, so Mr. Lenz was skeptical of the chances of TNT leaking out of the bombs, which is a necessity for our project. The types of bombs Mr. Lenz usually encounters have very thick metal casings (6 mm and thicker) and although they rust, it is very rare that corrosion forms spots where TNT can leak out. However, he mentioned that “a free lying bomb might emit some gaseous TNT, which can be detected, although it has very low concentration.” Another opportunity for TNT to leak out is through cracks in the bomb shell, which can arise when the bomb is dropped on a hard surface. Unfortunately for us, this is quite exceptional. Yet another way of the bomb emitting TNT is under stress our partial explosion, but this is very rare.

We can conclude from this that our TNT-sensing module will probably not be very suitable for the detection of unexploded ordnance. However, there are still possibilities for the detection of other kinds of explosives, which are not sealed that well.

Visit to the Explosieven opruimingsdienst

We visited the Explosieven Opruimingsdienst Defensie (EODD) in Soesterberg. The Explosieven Opruimingsdienst Defensie , which literally translates in Explosive cleanup service from the department of defense, is a branch of the Dutch military responsible for the disposal of explosives in the Netherlands and on military missions in foreign countries. We had a meeting with Luitenant Kolonel (Lieutenant-Colonel) Bergman, commanding officer centre of expertise EODD. We discussed the activities of the EODD, our landmine sensor and possible applications of the sensor in their operations.

“Our activities can be split in two equal parts,” Lt Col Bergman told us, “fifty percent national operations and fifty percent of what we call “out of area” operations. The national operations mostly consist of removing unexploded ordnance for World War II, but also the disposal of possible improvised explosive devices (IEDs) such as bags left at the airport with wires sticking out.” The discovery of unexploded ordnance still happens very often. In 2013, the EODD received 2300 notifications of such findings. “We have five teams on the road every day for the disposal of unexploded ordnance,” Lt Col Bergman mentioned. Those teams are available 24/7 to prevent the sometimes life-threatening situations that occur. Lt Col Bergman: “This work is not without danger. A colleague of mine lost a part of his arm when removing a bomb attached to a traffic enforcement camera.”

For the detection of unexploded ordnance in national operations, first a screening is done. This kind of area screening is mostly done in the preparation of large building projects. Such a procedure consist of the research of historic documentation and doing sample measurements with a metal detector. Bergman: “We increasingly also “walk in the area digitally”, making use of explosives detecting robots.”

For the out-of-area missions, people of the EODD are deployed in foreign countries (often war zones) to remove explosives hampering military operations or endangering civilians. “We have been active in recent conflicts such as the war in Iraq and the war in Afghanistan. Currently, people from the EODD assist special forces deployed in Mali, West-Africa. Also, the EODD is investigating the crash site of Malaysia Airlines Flight 17 [plane with about 200 Dutch citizens shot down above the East of Ukraine], trying to resolve how and by whom the plane was shot down.”

“In Afghanistan we encountered a lot of IEDs,” Lt Col Bergman continued. “At first they were made with a lot of metal, which we could easily detect with a metal detector, but then the Taliban started to make IEDs with less or even no metal at all. This rendered our metal detectors useless, so we used dogs to detect the IEDs. Dogs are very good at detecting explosives, but the problem is that they indicate the main charge, while you would like to find the trigger.”

We were wondering if the “traditional landmine” was still in use, since you hear mostly about IEDs in the news. Unfortunately, it is: “Landmines are used in every conflict. Besides that, it takes a couple of seconds to lay a landmine but it might take decades to remove it. There is still a lot of trouble with landmines laid during the conflict in the Balkans and the war between Egypt and Israel.” Besides landmines, also cluster bombs provide a large threat. Cluster bombs are large bombs with many small mines/bombs inside; these small bombs are spread around the site of impact. Bergman: “About 10% of the bombs do not explode. In the case of a cluster bomb with 200 bombs in it, this means that twenty new landmine-like bombs are laid upon impact. In Iraq, where cluster bombs were heavily used, we usually found them by asking kids. They exactly knew where the bombs were, since the bombs marked the boundary of their football field.”

When telling Lt Col Bergman about our landmine sensor, he tells us: “The development of new landmine detection methods is a real business opportunity. Currently, there is no method that can say with 100% certainty that an area does or does not contain landmines. Therefore, a lot of new detectors are developed. We have an intensive collaboration with TNO (Netherlands Organisation for Applied Scientific Research) to test them and buy only the best of the best.” We explained our project in more detail, especially how it is dependent on whether TNT leaks out of the bomb. After the meeting with Mr. Lenz from the Kampfmittelräumdienst, where he showed us how thick the shells of the bombs were they usually encountered (aircraft bombs), we had some doubt about the fact if TNT would leak out at all. Lt Col Bergman told us that for aircraft bombs, this is probably true, but that most other types of bombs have quite thin shells in which leaks occur easily. “IEDs are often made of jerry cans, which will always contain traces of explosive material inside and outside. Also landmines usually have very thin shells. These will have leaks, especially when they are in the ground for a while.” Lt Col Bergman showed us a truly enormous amount of different bombs to corroborate his statement (see photos).

From this, it seemed like the bombs that pose problems for our method, namely those with thick metal walls, are quite easy to find, and that the bombs which are more suited for our method (thin-walled bombs) usually have low metal content and are hard to find with current methods. Bergman confirms this: “The methods seem quite complementary.”

We asked Lt Col Bergman how important speed was for the detection of bombs, since promoter-based biosensors like ours are inherently slow. “When on out-of-area missions, we have to clear a route before a patrol drives there, so if the detection method is slow, we’re halting the whole convoy. However, if you can somehow spray your bacteria on the area the night before and this method would make the bombs clearly visible, it would be a great method.” Furthermore, Lt Col Bergman indicates that our method is well suited for screening of, for example, building sites.