We tested different application methods of activated carbon for sediment remediation

This blog post is based on our recently accepted publication in Water Research (Vol. 114, p. 104-112; http://dx.doi.org/10.1016/j.watres.2017.02.025). It is available free of charge until 15. April 2017 under this link.

Activated carbon is a sorbent with the capability of strongly binding pretty much any organic substance to its surface (a process called adsorption). Since a large share of pollution in aquatic ecosystems concerns such organic substances (for example PCB’s), it would hence be a suitable sorbent to remediate them. Once a pollutant is adsorbed to the activated carbon, it is bound so strong that it is no longer available to organisms. This includes even the case where they eat the activated carbon particles “coated” with the pollutant. The organisms would just pass it through their digestive system, pooping it out unaltered. So, long story short, the idea is to render pollutants harmless to the environment, rather than having to remove them (which additionally leaves the question where to put the removed pollutant).

Unfortunately it has been shown that activated carbon itself can actually be quite harmful to certain animals. Therefore, it is necessary to not focus solely on developing these novel remediation methods to be as effective as possible, but to ensure that they are also safe to apply in the environment. After all, what does it help us if we treat the pollution in a place, but at the same time wreck its ecosystem?

In the paper this post is based on, we mainly examined several different methods of applying activated carbon to polluted sediments (which is where the major share of pollutants in aquatic ecosystems are). You basically have two general options: the more laborious one of mixing the sorbent into the sediment actively, or the more “crude” way of thin layer capping. In the latter method you just cover the polluted sediment with the activated carbon (see picture 1). In the field that would mean all you need to do is to take a shovel and spread the carbon. So, while we did know that thin layer capping would be the easier method to execute, what we aimed to find out in our tests was how it compares in matters of effectiveness and safety.

Picture 1: The setup of our test vessels (only thin layer cap tests shown). The activated carbon is applied as a thin layer on top of PCB polluted sediment. Underneath, the burrows of the test organism (Lumbriculus variegatus – a worm living in the sediment) are visible.

We simulated the two application methods in the laboratory in test vessels containing sediment from a PCB-polluted site (Lake Kernaalanjärvi, southern Finland). As a test organism we used Lumbriculus variegatus, small worms that burrow through the sediment. The amount of PCB’s that the worms take up from the test sediments told us how well the different treatments work for remediation, while their biological responses (things like their change in body mass) were used as parameters to measure the adverse effects of the sorbent material itself.

Picture 2: A quick graphical overview on the results of our results: Adverse effects can be comparably high, but remediation efficiency (meaning the reduction of the uptake of a pollutant (here: PCB) is best when activated carbon is mixed into the sediment.

The major results published in this paper were both promising and worrying at the same time (picture 2). We found out that both methods are effective in general. Worms living in sediment under a thin layer cap took up ~50% less PCB’s from the sediment than from the untreated, “raw” sediment. When the activated carbon was mixed into the sediment, the uptake of PCB’s was prevented almost completely. So, while thin layer capping is a method that is a lot easier to use (and hence cheaper), it is not quite as effective as mixing the sorbent into the sediment. Nevertheless, one has to also keep in mind, that animals dwelling in the sediment (and the thin layer cap) can mix the activated carbon with the underlying sediment. This process is called bioturbation and it was actually even visible in our laboratory test vessels (picture 1). It’s just a lot slower than mixing sediment and sorbent right away upon application. In addition, mixing via bioturbation of course requires animals to stay on the treated site and not to flee the site in panic when the activated carbon is applied.

And that’s exactly where our more worrying results come in: the adverse effects of the sorbent itself. With both application methods it became quite apparent that the worms did not really like our miniature-scale remediation works. They lost their appetite almost completely, stopped feeding and hence lost a lot of weight. While that may sound like a desirable achievement to some humans, for our worms that could be a serious issue.

A possible explanation for this sudden loss in appetite was found on electron microscope images that we took (picture 3). It looked like the activated carbon had quite some detrimental effect to the worms’ gut walls. Their microvilli, which are responsible for nutrient absorption from the gut content, were damaged severely in most worms exposed to sediment treated with the sorbent – no matter with what application method. The exact mechanism on how activated carbon causes this kind of damage remain obscure; one suggestion for example is mechanical abrasion (the carbon particles are quite sharp), but also the strong sorption capacity of the material might be involved.

Picture 3: Activated carbon can damage the gut walls (specifically the microvilli) of Lumbriculus variegatus. Image as seen through an electron microscope at a 6000x magnification.

One interesting thing we saw was that thin layer capping with activated carbon can have quite a devastating effect on Lumbriculus variegatus. This is not too surprising, since the organisms are exposed to a high dose of pure activated carbon at the sediment-water interface. However, when we mixed the activated carbon with clay before applying (thus creating a thin layer cap that resembles natural sediment that is enriched with the sorbent), the adverse effects were a lot less severe.  This doesn’t mean there were no more adverse effects, but rather that they were at a comparable level to our other tested application method of mixing the activated carbon into the sediment.

Picture 4: The transmission electron microscopy images (which you saw above) in the making. Photo: Inna Nybom.

From the results seen in this study we were able to draw some conclusions and implications for future field applications. To sum up, both methods are effective. What the thin layer capping method lacks in immediate effectiveness, it makes up for with its easier application and lower costs. When it comes to the adverse effects, we showed that neither one of the methods has a significant advantage over the other – if certain precautions, like avoiding to apply pure activated carbon, are made. So when deciding on a method, the important factors are mostly the available budget and equipment. Thin layer capping is a better option for sediment remediation in cases where special equipment required for other methods cannot be brought in easily (remote areas) or simply in cases where funds are limited. However, before deciding whether or not to utilize activated carbon in general (and big scale), we will have to make sure that its own adverse effects to the environment are not worse than the pollution effects!

Lastly – if you check our blog post on the first field trial of activated carbon based sediment remediation in Finland, you will probably spot some of these implications already “in action”!

Text: Sebastian Abel

Pictures: Sebastian Abel, Inna Nybom

Riding the emotional rollercoaster of publishing scientific articles

Publishing scientific articles is an important part of researcher’s life. The process is full of ups and downs, especially for a young researcher. Planning and writing the manuscript is another story, but there is lot to expect after you think you have finished your manuscript.

The emotional rollecoaster of publishing scientific articles.
Polishing

The final polishing takes a surprisingly long time. Is everything according to the journal’s requirements? Fonts, figures, colors, spacing? Do you need separate files for everything or do you build a single file including figures? What kind of reference formatting is required? For me, this is the happy phase. I feel that my hard work pays off and I am actually finishing a part of my work. I can’t wait to get that manuscript for the reviewers!

Submitting the manuscript

With my first manuscript, this was the phase where I started to have doubts. You need a cover letter for the editor. What on earth am I supposed to write in there? And how do I find the most suitable referees? So many forms to fill and the figures do not show as I planned. Can I be sure that everything is ready to be submitted? Did I make all the last corrections to the text after the proofreading? Since I am not a native English speaker, there is a bit more stress in that part.

Review process

Relieved to get the manuscript out of your hand. Expectations are high and the process seems to take way too much time. Unless you get a quick response from editor saying that your manuscript doesn’t fit to the scope of the journal, or that they have recently published a similar paper. Then it’s just waiting. When I finally get the response, my feelings go up and down. Well, of course, if it’s not a blunt rejection. Major of minor changes – Yay, there is light at the end of this tunnel! On the other hand, the comments from the reviewers prove that there is still a lot of work to be done before the article is published.

Finishing line

In the end, you will have the paper in your hand, with your name on it and everything. Should I send it to my family to read (didn’t, I guess they wouldn’t appreciate it that much). Maybe I could bring some sparkling wine or a cake to colleagues? Part of my PhD thesis is now completed and it’s time to move on to the next part!

Celebrate the good work you have done!

 

Text by Kristiina Väänänen, photo by Kaisa Figueiredo

Microplastics and ecotoxicology

Science is partly about trends and what is currently in fashion. Don’t get me wrong, this does not mean that the hot topics are somehow unnecessary to study. It is just something for which you find funding at certain time. As an example from the field of ecotoxicology nanoparticles are a perfect example. If you went to international ecotoxicology congress ten years ago there was hardly any presentations about nanomaterials. The evolution was pretty quick and soon one could catch several sessions on nanoecotoxicology in those same congresses. Nowadays it is blended in, which means that nanoparticle presentations are part of “normal” sessions.

Studies about the microplastics in the environment are currently going through the same progress. The hype has not peaked yet, but getting there. And no doubt plastics are a huge problem in the environment. While ecologists seem to take main responsible about bigger plastic litter the smaller pieces called microplastics draws the attention of us ecotoxicologists. This is probably because we have learned to study the fate and effects of tiny particles (=nanoparticles) during the past decade. The differences is that in the case of nanomaterials we have done something that can be called predictive ecotoxicology i.e. for the most parts we have been trying to figure out the potential effects of nanomaterials if or when they reach the environment. There are still many open questions connected to this. For example the fundamental question if the tools and dose metrics developed for chemicals are doing the job in the case of nanomaterials. They are particles by the definition and they don’t behave like chemicals.

In the case of microplastics the things are maybe even trickier. In most cases we don’t know what to test. Primary microplastics are in micro-sized already in the applications they are used (e.g. cosmetics) whereas secondary microplastics are formed in breakdown of bigger plastic litter due to various environmental processes. Currently we don’t know the ultimate fate or the degradation rates of different plastic types in variable environments. But we do know that at least at certain sites the average particle size is shrinking. This means that we don’t necessarily add more plastic to these systems but the plastic that is already there is breaking down into smaller particles.

So, we don’t yet know what we have there and which kind of problem they are. This applies especially to freshwater environments. At the moment we are mostly testing different types of commercial round shaped particles of certain precise size. Looking at environmental samples the reality is different. We have a mixture of odd shaped particles and different types of fibers. This already suggests that banning the use of microbeads does not necessarily do the trick, although all reductions of plastic input into the environments is good. The previous is underlined with the fact that there are indications that in fish for example we do not find beads but for example fibers, whereas in the surrounding environment we have the beads. Plus we have the emerging secondary microplastics with various types and shapes. To overcome this shortage we need to develop sampling and analytical methods and do more research overall. After that we know which particles/plastic types we should be worried about.

microfiberPotential sources for microfibers (left) and polyester fibers found in water fleas after laboratory exposure (right). Photos by Dr. Napaporn Leadprathom.

Also, I don’t think that the degradation processes stop at micro it continues to nano. Then the properties, environmental fate and effects of plastics may change as we know from the nanomaterials research. We should look into that as well starting with development of methodology for sampling and analyses.

P.S. During this increasing interest in microplastics it is sad to see news like below:

http://www.sciencemag.org/news/2016/12/misconduct-allegations-fly-spat-over-paper-microplastics-and-fish-larvae

I don’t see a good result for this. Either the authors heavily violated the good scientific conduct or they have been falsely accused. In both cases it is bad news. Anyway, I hope that the truth finds its way.

Akvaattisen ekotoksikologian käytännön töitä laboranttiharjoittelijan silmin

Kun aloitin harjoittelun, oli käynnissä matokoe. Kokeessa tutkittiin, miten erilaiset pohjasedimenttien fullereenipitoisuudet vaikuttavat harvasukasmatoihin. Kokeeseen liittyi työtehtävinä mm. veden pH-mittausta ja happipitoisuuden mittausta. Myös näytteiden pohjasedimentin pH:ta mitattiin. Jos veden pH oli matopurkeissa liian alhainen, niiden vesi piti vaihtaa.

Harvasukasmatokoe eri fullereenipitoisuuksilla.
Harvasukasmatokoe eri fullereenipitoisuuksilla.

Ennen kuin aloitettiin uusi matokoe, leikattiin harvasukasmatoja kahtia. Hännät säästettiin seuraavaan kokeeseen. Ennen kuin fullereenisuspensio oli lisätty pohjasedimenttiin, suspension pitoisuus oli tarkistettu UV/Vis-spektrometrilla. Matokokeeseen tehtiin myös keinotekoista makeaa vettä. Siihen tarvittiin magnesiumsulfaatti-, kalsiumkloridi-, kaliumkloridi-ja natriumkarbonaattiliuoksia sekä milliQ –vettä. Näitä kaikkia lisättiin suureen pulloon ja sekoitetaan magneettisekoittajalla. Liuoksen pH mitattiin ja säädettiin.

Matokokeessa madot laitettiin purkkeihin, jossa on pohjalla sedimenttiä ja kvartsihiekkaa ja niiden yläpuolella keinotekoista makeaa vettä. Purkkien sedimentteihin on lisätty kolmea eri fullereenipitoisuutta. Sedimentti oli otettu järven pohjalta. Purkkeja oli hapetettu yön yli. Kaikkiin purkkeihin lisättiin 10 matoa. Madot saivat olla purkeissa kaksi viikkoa, eikä niitä hapetettu. Matopurkkien pH-arvoja ja happipitoisuuksia mitattiin kokeen aikana. Näytepurkeista kerättiin myös pellettiä useaan kertaan. Pelletit suodatettiin ja niiden paino mitattiin. Kun kaksi viikkoa oli kulunut, seuloimme matopurkkien madot. Mittasimme iltapäivällä kaikkien matopurkkien matojen painon ja laitoimme ne koeputkiin suolaliuokseen. Koeputket laitettiin pakastimeen.

Pellettien suodattaminen.
Pellettien suodattaminen.

Ekotoksikologian kasvatushuoneessa kasvatetaan kirppuja, harvasukasmatoja ja surviaissääskiä. Niitä ruokitaan kolmesti viikossa. Kirppualtaiden vedet vaihdetaan kerran viikossa. Myös muiden eläinten altaiden vedet vaihdetaan kerran viikossa.

Harvasukasmatojen kasvatusallas.
Harvasukasmatojen kasvatusallas.

Vesikirpuilla tehtiin toksisuuskokeita. Ensin tehtiin akuutteja toksisuuskokeita. Fullereenisuspensio suodatettiin ja sen pitoisuus mitattiin UV/Vis-spektrometrilla. Sitten tehtiin akuutti toksisuuskoe, jossa käytettiin toisena altistavana aineena fullereenia. Sitten aloitettiin kemikaalien yhteisvaikutuksia tutkiva pitkäaikainen toksisuuskoe vesikirpuilla. Kyseessä on lisääntymiskoe. Kokeessa voidaan tutkia useita vesikirppusukupolvia ja niiden jälkeläistuotantoa, sukupuolijakaumaa ja emokirppujen kokoa. Vesikirppujen sukupuolta tutkitaan mikroskoopilla. Pitkäaikainen toksisuuskoe on vielä kesken. Vesikirppujen toksisuuskokeet liittyvät erään opiskelijan pro gradu -tutkimukseen.

Vesikirppuja käytetään kemikaalien toksisuuden arvioinnissa, tässä tutkitaan vaikutuksia lisääntymiseen.
Vesikirppuja kemikaalien toksisuuden arvioinnissa.

Tein harjoittelun lopuksi kaksi näyttöä:

  1. Fullereenisuspension pitoisuusmääritys UV-Vis-spektrometrillä
  2. Vesikirppujen sukupuolijakauman ja emojen pituuden määritys kemikaalien yhteisvaikutuksia tutkivassa pitkäaikaiskokeessa

Teksti ja kuvat Päivi Hämäläinen

Onnittelut myös Päiville hyvin suoritetuista tutkinnonosista!

Ällömadot ja ihanat kirput – laboranttiharjoittelijan kokemuksia

Yksi vakiotehtäviä harjoittelun aikana oli vesikirppujen huoltaminen. Kirppuja pidetään yllä odottamassa mm. kemikaalien myrkyllisyyden kokeita. Kirpuille annetaan ruoaksi levää, jota myös kasvatetaan samassa kasvatushuoneessa, kasvatushuoneesta löytyy myös ällömatoja (harvasukamatoja) ja chironomus sääskiä.

Harjoittelun mukavimpiin kuuluva asia on ollu kirppujen huolto, ja tykästyin niihin jo alkuvaiheessa. Monet sanovat etteivät ne näytä erityisen mukavilta otuksilta, mutta livenä niiden katselu on todella rauhoittavaa, ja niistä löytyy paljon mielenkiintoista mikroskoopin alla, tai paljain silmin katsellessa.

risto1

Näissä kuvissa näkyy vesikirpun poikasten kasvaminen, koko tämä tapahtuma on vain muutaman päivän sisällä, ja poikaset saattavat hyvissä tapauksissa tehdä oman poikueensa jo noin viikon ikäisinä. Emot kasvattavat munat selässään, ja poikaset kuoriutuvat emon kuoren sisässä. Kun poikaset ovat valmiita, emo avaa kuortaan ja ne syntyvät aikuisen vesikirpun näköisinä, ja kasvavat nopeasti syntymänsä jälkeen.

risto2

Viimeisessä kuvista poikaset ovat jo valmiita syntymään, ja edellisessäkin poikanen on jo melkein aikuisen muotoinen. Näissä molemmissa kuvissa poikaset ovat alle vuorokauden sisällä valmiita syntymään.

risto3

Vesikirput lisääntyvät normaaleissa olosuhteissa suvuttomasti, naaras tuottaa jälkeläisiä ilman koiraiden asiaan puuttumista. Näkyvänä erona koirailla on suussaan pidempi tuntoelin ”sikari”. Tässä kuvassa erottuu naaraan lyhyempi suukappale.

Toinen ympyröity osa on kirpun sydän, joka mielenkiintoisesti sijaitsee niskassa, muutenkin vesikirppujen elinten ja osien sijainnit poikkeavat hyvin paljon ihmisille totutusta, suoli on osin päässä yms.

risto4

Pintamikroskoopin alla kirput erottuvat aivan eri tavalla. Näistä erottuu paremmin muodon pyöreys, mutta mikroskoopin alla katsoessa on silti vaikea nähdä, miten kuori on muodostunut, kuori on kaksiosainen, ja kokonaisuudessaan kirppu muistuttaa lähinnä simpukkaan pukeutunutta merihevosta. Sisäosat ovat suurelta osin erilliset kuoreen nähden, ja kirput kasvaessaan vaihtavat kuorta.

Tein harjoittelun aikana myös oman kokeilun. ->toksisuuskokeissa käytetään myös harvasukamatoja, joiden kokeen onnistumisen takia täytyy aloittaa syömään sedimenttiä samoihin aikoihin. Se onnistuu leikkaamalla mato puoliksi pari viikkoa ennen kokeen aloittamista, jolloin madot kasvattavat uuden pään. Jakautuminen on harvasukamadoille luonnollinen tapa lisääntyä, ja leikkaaminen käynnistää tapahtuman samalla tavalla kuin luonnollinen katkeaminen. Joten, halusin tietää selviääkö mato jos sen leikkaa useampaan osaan, kokeissa on käytetty vain joko pää- tai häntäpuolta.

risto5

Leikkasin kymmenen matoa siis viiteen osaan. Madon palat elivät muutaman viikon samanlaisissa olosuhteissa kuin muutkin kasvatushuoneen madot. Lopulta kun laskin elävien matojen määrän, olin kieltämättä vähän yllättynyt. Vaikkeivat madot olleet lisääntyneet, niitä ei myöskään ollut kuollut. Kaikista purkeista oli kuollut vain kaksi matoa. Keskimmäisestä osasta kasvaneet olivat kaikkein terveimmän oloisia, ja hännänpään palat olivat vain juuri ja juuri kasvattaneet uuden pään.

Ällömadot on jänniä mut silti ällöjä. Mut kirput on jänniä ja hitsin ihanoita.

Teksti ja kuvat: Risto Pöhö

Good coffee makes a day! Which brands are our favourite?

In our laboratory and office we do high-quality environmental research, but nothing gets us awake to a new working day better than a good coffee! Fresh made coffee has become an important part of our daily routine and little by little we have created a semi-scientific approach to coffee brewing and tasting. We brew our coffee two to three times a day using a basic French press coffee maker and an electric water boiler and normal tap water, which originates from ground water in the Joensuu region, known for its good qualities and excellent purity. In our opinion, coffee has its optimal taste when enjoyed on a ceramic or clear glass coffee mug. Our favourite type of coffee is dark or medium dark roast, and we appreciate organic coffee and ecological and fair trade values, independent on the origin country. We also enjoy tasting new coffees and never stick to one particular brand or type for more than one package at a time. Together with the coffee we always use milk, preferably Arla´s Café-maito or any other whole milk available. Skimmed or semi-skimmed milk is a no-no with coffee. Our department has a shared coffee room where coffee is brewed constantly throughout the day, but we have decided to stick to our own routine and preferences when it comes to coffee and its additives. This has led to several curious co-workers passing by our office after having smelled a delicious scent of good coffee in the corridor outside of our office.

A couple of months ago we came up with an idea to taste new coffees that we had never tasted before. We sent email to some coffee roasters in Finland and asked them for advice for coffee selection. Two of them kindly offered us some of their coffees for tasting, and so we put up an official female scientist’s coffee tasting club at the office number 368. Our high-qualified test group will be introduced here: Krista Väänänen has always been a tea drinker, but after moving to our office and getting under the influence of other coffee drinkers, she has also started to appreciate good morning and after lunch coffee. Kukka Pakarinen, instead, is heavily addicted to coffee and cannot start her mornings without a strong coffee shot, otherwise she would get doctoral withdrawal symptoms. Kaisa Figueiredo, the 3rd member of our tasting team, has been married to a Brazilian for almost 10 years, and therefore good coffee comes for granted in her family.

The free samples that were kindly sent to our coffee tasting. Left: Kaisa with package from Paulig. Right: Kristiina with Kaffiino coffees.
The free samples that were kindly sent to our coffee tasting. Left: Kaisa with package from Paulig. Right: Kristiina with Kaffiino coffees.

Oy Gustav Paulig Ab kindly sent us two packages of their UTZ-certified coffees: Mundo (roasting level 3, on a scale 1 to 5) and Brazil dark roast (level 3½). Kaffiino roastery offered to us two different coffees from their quality selection: Guatemala Huehuetenango and Colombia Woman´s Coffee Project, both with roasting level 3. Additionally, we bought one package of Arvid Nordquist REKO, Meira’s Kulta Katriina dark roast premium, and Paulig´s new city coffees café New York and café Havana to complete our test procedure. As an extra bonus sample, we had Dunkin Donuts Pumpkin Spice flavored coffee brought directly from the United States of America, where one of our group members went on a conference trip in November. All of these sampled coffees were ground to suit a French press coffee maker and therefore fitted well for our needs.

What can we say about the coffees then? It was difficult to define if one coffee was better than another. Paulig’s Brazil dark roast is a very good coffee for basic everyday use, and we preferred that over Paulig’s Mundo. Although Mundo is organic and UTZ-certified, its flavour did not reach the qualities of the others. However, the city coffees New York and Havana were proven excellent coffees as well. The medium roasted New York has a well-balanced taste and it will be our future favourite to serve in parties and gatherings. Dunkin donuts gave a good boost for upcoming Christmas time, but after all was our least favourite of the selected coffees. Instead of filling the coffee maker with Pumpkin Spice flavoured coffee, we mixed one coffee scoop of that and five scoops of Kulta Katriina’s dark roasted coffee, and still felt the flavour very strongly in our coffee. The taste was rather sweet and artificial, and the coffee itself was a bit too light to our taste.

 Kukka with Kulta Katriina Premium dark and Dunkin Donuts Pumpkin spice coffee.
Kukka with Kulta Katriina Premium dark and Dunkin Donuts Pumpkin spice coffee.

Kaffiino offered us two special coffees, which we immediately felt that were “luxury” for us. Beautiful well-designed packages, delicious scent and a perfect grind for French coffee makers. Both coffees that we received from Kaffiino were very good, but of some reason did not convince us at a first taste. However, from the second taste onwards they tasted excellent, and the only bad thing about the coffees were that they did not last for the whole week. Going back to market selection after drinking these great coffees was a bit disappointing. By the way, did you know that in Kaffiino’s web shop you can buy a large selection of coffees from different origins, and even design your own label for the coffee package? What would be a better Christmas present than a good coffee with your personalized label?

Finns are the people with the highest consumption of coffee in the world, at 12 kilos per person per year and coffee in Finland has traditionally been roasted lightly, brewed with a filter coffee maker and enjoyed pure, or with sugar/milk. After all, when it comes to coffee preferences, it is always a matter of taste – some like it espresso-like dark and strong, while the others have it filtered and light, or anything in between. Others buy the cheapest supermarket coffees, while others pay attention on the roast, origin and ecological aspects. We have made our choice and we thank our sponsors Paulig and Kaffiino for offering us a tasting menu from their selections. The winner of the competition is Kaffiino’s gourmet coffee Guatemala Huehuetenango, which definitely was creamy and full-bodied as stated in its description.

Text by Kaisa Figueiredo, photos by Kristiina Väänänen

Schooling lab assistants – a new perspective to lab work

This fall we have two lab trainees, Risto and Päivi, working in our group. They are studying in North Karelia Adult Education Centre to become laboratory technicians. The education includes both lessons in the college and practical training in work places. Students have to pass altogether six working exams; in laboratory field this means exams in basic lab work, organic chemistry, analytical chemistry, and bioanalytics, and two optional exams among own interests and possibilities in workplace. Our lab offers training in basic lab work, analytical and environmental chemistry, and biotechnical applications as well.

During their training period, students are working as a part of our group doing everyday lab works learning new methods and deepen their occupational skills. On the other side, they bring new sights and ideas enriching the workplace. Another benefit is that supervising forces you to think your work thoroughly: how and why different stages in the work are done. It is observing your own manages by another’s eyes. In the best case, interaction with students produce new and practical methods. I hope that those moments are great for students, too.

Our old, rather shaky and bulky experiment system (left), and new, compact setup (right) developed by Risto.
Our old, rather shaky and bulky experiment system (left), and new, compact setup (right) developed by Risto.

An important goal for students is to pass work exams during the practical training. Thus, we need to plan “work-packages” for chosen exams. This is a bit difficult part, because many criteria set by the college must be fulfilled for each exam, and the work must be included in the everyday lab work at the same time. In the best situation in exam, students just do their daily work under appraisers’ observing, and then their performance is evaluated.

In the exam, there are three appraisers representing both college and workplace. They observe student’s work and ask questions, and finally have a meeting to decide the grade; exciting and interesting event overall.

We have already organized Risto’s exams. Everything went great! Let pictures tell more:

1) Artificial freshwater for Kristiina’s experiment is under preparing, 2) Risto was asked to calculate some concentrations, 3-4) Doing toxicity test is painstaking job, 5) Centrifuging and telling about the equipment, 6) Observations are booked through the exam day, 7) Going to the evaluation meeting, 8) Finally it’s over!
1) Artificial freshwater for Kristiina’s experiment is under preparing, 2) Risto was asked to calculate some concentrations, 3-4) Doing toxicity test is painstaking job, 5) Centrifuging and telling about the equipment, 6) Observations are booked through the exam day, 7) Going to the evaluation meeting, 8) Finally it’s over!

Congratulations for Risto for his great work!

Text and pictures by Kukka Pakarinen

Work outside the lab – field work in lakes

It was time for a field trip, once again. In my project, I have been sampling lake waters, sediments and benthic organisms for several times. I’ll go to the field either during late winter (April) or in autumn (October). Surprisingly enough, it is easier to work in winter, when you have a solid ground – meaning half a meter of ice. In winter, you just saw a hole and start working. It is much easier to get to the lake with a snowmobile than with a large boat trailer.

No rain, barely any wind... is this even possible? Perfect autumn weather in Lake Parkkimanjärvi.
No rain, barely any wind… is this even possible? Perfect autumn weather in Lake Parkkimanjärvi.

For a researcher working mostly in office or lab, it is always fun to go outside. In lab, it often takes months and months to get any results. In field, it’s easier to feel you have accomplished something. It is also a good reminder that our lab conditions are far away from ”real life” in nature. Each time in field, we face surprises: the weather is impossible, benthic organisms have disappeared, fisher’s nets are exactly in the planned sampling point or the equipment break in the middle of nothing. A perfect opportunity to develop your problem-solving skills!

The lakes are mostly located 200-300 km from our university, meaning that you have to prepare everything carefully. If you leave something behind, too bad! This time we got everything we needed. Our goal was to collect chironomids (larvae stage of a non-biting midge) from lake bottoms. We are happy to have a technician with creative mind: He has built us a pump to collect the bottom sediment.  The sediment is taken to a boat (120 l at the time) and sieved in buckets on board. This is repeated as long as we have enough chironomids – most often meaning 1200-1500 l of sediment going through our hands. The work is hard and muddy, the daylight hours are short.

Left: the little red one is our catch, right: Researchers are warm and happy with their seven layers of clothing.
Left: the little red one is our catch, right: Researchers are warm and happy with their seven layers of clothing.

Happily enough, the weather was great. No rain, no ice cover. In picture below, you see the nice surprise we had one autumn: We arrived to the lakes and they were frozen. It is not an easy task to break even a thin ice layer for several hundred meters.

Surprise, it is winter! Good luck with getting the boat to the lake.
Surprise, it is winter! Good luck with getting the boat to the lake.

First three lakes were rather easy. We had a larger boat and there were lots of chironomids to be collected. For the last two lakes, the situation was getting trickier: the lakes were small and shallow, so we needed to change to a smaller boat. Firstly, the roads to the lakes were almost non-existent. And secondly, it was almost impossible to get the boat to our final lake. Yup, the picture below is from a lake. We wore wading boots, because we sunk to our knees in the mud. And since the water was really low, we had to push the boat for more than hundred meters. It is also much more difficult to work in such a small boat.

Left side: hard work with shallow waters and muddy bottom, right side: a Finnish road and our equipment.
Left side: hard work with shallow waters and muddy bottom, right side: a Finnish road and our equipment.

Thank you Kari, Jenny and Nina for your hard work! Without you, I would still be standing next to our first lake, probably crying.

Text by Kristiina Väänänen, photos by Kristiina Väänänen, Jenny Makkonen and Jarkko Akkanen.

Mentoring – towards great success

Last spring, my labor union (LAL, the Finnish Union of Experts in Science) was looking for people to participate in their mentoring program. Since I am going to finish my PhD in the near future, this seemed like an opportunity I shouldn’t pass. I made the application, took the Skype interview and was finally selected. Yay! ( BTW, how weird it is to see yourself in a webcam, my hands were flying around constantly)

The next step was to find a suitable mentor and contact him/her. This was really challenging: what kind of mentor am I looking for? Suitable degree? Interesting experience? Career in academia, or maybe in private sector? Age? Working experience in years? Does the sex matter? Where do I find the perfect person?

I ended up with few good options, chose the one I thought would suit me best and send an email. Quite soon, I got a positive answer and we talked on the phone. Final solution, I have a mentor! My mentor, Anneli Tuomainen is working as Senior Advisor in business development and innovation environments in Kuopio Innovation. She has a combination of education in natural science (PhD, docent) and work experience in research institutes and companies (R&D&I).

We met few times to get to know each other before the official program kick-off. I was relieved: when it comes to expertise, she is hard as rock. Otherwise, she is really approachable and easy to talk to. I believe we are going to have many fruitful discussion during the upcoming year.

Meeting my mentor in the beautiful city of Kuopio.
Meeting my mentor in the beautiful city of Kuopio.

This week, we had the first meeting with all the participants in the program, approximately 16 actors with their mentors. We had many group discussions and we used a lot of time to clarify our goals and motivations. How would you describe work life using the pictures below? One person in our group had a great thought: There are two roads for you to choose from… but you may also end up in the middle of the field.

Hard work in the first group meeting.
Hard work in the first group meeting.

The day was long, but rewarding. Besides the actual program, it takes time to travel between Joensuu and Helsinki. Everything was organized extremely well. You could see the trainers were not doing this for the first time. The mentoring program is organized in co-operation between several unions.

Now I’ll continue figuring out my strengths, skills and weaknesses. Next meeting, we’ll give an elevator pitch. What a challenging, but important task!

Building a mind map of my skills.
Building a mind map of my skills.

Text and pictures by Kristiina Väänänen

Sediment field clean-up trial, Part 2: setting up and monitoring the actual field trial

In Part 1 of this Blog post we took a look at the on-site sediment remediation with activated carbon. Now we will gain a small insight to the first field trial of the method in Finland, which was started by our group in August 2015.

The test site lies in Lake Kernaalanjärvi, which was contaminated with PCBs between 1956 and 1984. There was a steady, unnoticed discharge of the chemicals from a paper mill upstream one of the lake’s feeding rivers (Tervajoki). Since no one noticed that leak for so long, quite an amount was released to the river and ended up in the lake eventually. The fact that this is still a problem nowadays, even though the leak was shut down over 30 years ago, gives you a hint on the persistency of PCBs in the environment.

Lake Kernaalanjärvi, the site of the field test in winter (Plot marked). The feeding Tervajoki River – the source of the pollutants (PCBs) in the lake – is nicely visible.
Lake Kernaalanjärvi, the site of the field test in winter (Plot marked). The feeding Tervajoki River – the source of the pollutants (PCBs) in the lake – is nicely visible.

Since the lab trials had not only shown the high efficiency of activated carbon, but also potential risks of the sorbent particles themselves, we applied it only to a small plot of 300 m2 within the lake. This way we don’t mess up a whole lake, if the side effects are bad, but we also don’t waste too much money, if the clean-up potential is not as good as seen in the lab. The plot lies in the south end of the lake – the most contaminated area. This is right where the contaminated feeding river enters into the lake (see satellite image). With it come the PCBs, usually attached to suspended particles that settle as sediment once the water flow speed gets low enough.

For the remediation works, we ordered about 1000 kg of pressed pellets consisting of activated carbon and clay (Sedimite™). The latter increases the density of the pellets, making them sink faster to the bottom of the lake. This fast-sinking property makes handling and applying the activated carbon really easy. You can basically just shovel them out of a boat onto the water surface and they sink straight down onto the sediment. With pure activated carbon – usually a powder – that would be unthinkable. In part 1 of this post you could see a picture of the mess we can easily create already in the lab when we handle activated carbon powder. Add a bit of wind or rain (which we rarely see in the lab) to that and you might not have the greatest work day of your life. Even if the powder finally reaches the water, most of it would just get suspended in the water column and settle after days at wherever the water flow brought it.

The boat is loaded with activated carbon pellets (Sedimite™) – we’re ready to get going!
The boat is loaded with activated carbon pellets (Sedimite™) – we’re ready to get going!

For the application of activated carbon we had to first of all change our “lab rat” attitude to field-trial-mode: In the lab, we usually work with precisely measured doses, carefully applied in controlled environments. In the field, we had to take more of a “rough estimate” approach. We started by measuring a 10 x 30 m field on the lake, marking it with buoys and ropes. For better orientation and to achieve a more even layer of activated carbon, we diverted the plot into 5 x 5 m intersections, which were handled one at a time. After we had applied (read: shoveled) all of the pellets onto the test site, we took some sediment core samples of the freshly covered site. Luckily we could see that the pellets had actually worked as intended and we achieved a quite good layer of activated carbon on top of the sediment.

Applying the pellets to the marked plot on an average Finnish summer day.
Applying the pellets to the marked plot on an average Finnish summer day.

Now – about one year later – we checked in to see how the field looks like. We took core samples on the same spots again and unsurprisingly, the field looks a lot different. Wind and waves have affected the plot heavily:  a lot the sorbent has been swept away. In addition, a thick layer of new sediment has covered what was left on site.

Sediment core samples showing the applied layer of activated carbon one day after the plot setup and 10 months later.
Sediment core samples showing the applied layer of activated carbon one day after the plot setup and 10 months later.

How this is affecting the remediation potential and the adverse effects of activated carbon, we plan to find out in the near future. We have scheduled a lot of monitoring works, such as surveys on the condition of the local sediment fauna and changes in the PCB uptake by the organisms living on our plot.

Important part of every exhausting field trip: Beer and Sauna.
Important part of every exhausting field trip: Beer and Sauna.

Text by Sebastian Abel, photos by Sebastian Abel and Jarkko Akkanen