Toxicity of Nanoparticles - Hype or Reality

Sunnuntai 8.4.2018 klo 12.27 - Mikko Nikinmaa

During the recent past, the toxicity of nanoparticles (i.e. particles with at least one dimension less than 100 nm) has become a very fashionable field of toxicological studies. There is now ample evidence that the particles can be toxic, if their concentration is high enough. And that is the major problem of most nanotoxicological studies: the nanoparticle levels are often thousands of times higher than what can be expected to occur in the environment. Since one has now clearly shown that nanomaterial can be toxic, it would be high time to study the possible environmental relevance of the toxicity. If there is none, then the studies showing toxicity are irrelevant. This is because one can find toxic amount of any substance. For example, one can demonstrate a lethal dose for water. As Paracelsus said already in 16th century: All substances can be poisonous, the dose makes the difference between remedy and poison.

A significant problem with nanomaterial studies is that the methodology used is suitable especially for dissolved substances in aquatic media, but is not necessarily suitable for the new material. Hitherto, methods, which would be specific and good for nanomaterial research have not been developed. A significant property of nanomaterials is their tendency to aggregate, and the influence of this on the toxic properties is poorly described - it makes definitely a big difference if aggregation occurs before the contact with organisms or only after cellular uptake. One toxic effect of nanomaterials, which is independent of their metal components, is that they cause oxidative stress (and inflammation). This property may get worse with aggregation - we do not know. As the worst possible scenery one can think that nanomaterials cause similar problems in airways as asbestos: this may be fearmongering, but until environmentally relevant nanotoxicology studies are available, the possibility cannot be discounted.

Shrinking Ozone Hole - we can remedy environmental problems if we try

Maanantai 6.11.2017 klo 16.04 - Mikko Nikinmaa

An intergovernmental climate meeting just started in Bonn with the main message beforehand delivered: we are not doing enough! The pessimists have got further wind in their sails all through the year from Trump administration saying that they are withdrawing the USA from the Paris agreement.

In view of this, it is important to give hope.And the hope comes from the recent news that the Ozone layer is strongest since 1988. This measured fact shows that if we are united globally, the environmental problems can be solved. Further, the new solutions generate new outcomes.

This positive news creates hope for climate remedy. We can go forward from coal- and oil-dependent world. The new solutions are already present, and generate new paths to those who dare to look forward. Unfortunately, at the moment too many leaders and people of different nations want the past back. However, that is not possible, we must go forward, either by doing what needs to be done or enduring a catastrophe, the outcome of which no-one knows. Which alternative would you choose?

Plastics removal by micro-organisms

Sunnuntai 24.9.2017 klo 17.50 - Mikko Nikinma

Plastic garbage is a huge problem everywhere in the world. The most visible collections of mainly plastic trash are the Pacific Garbage Gyre and similar smaller ones in the Atlantic and Indian Oceans, but all the aquatic environments have plastic waste and non-visible microplastics. Plastic trash is a highly visible problem also in terrestrial environments.

In the light of the huge plastic pollution problem, two major solutions to alleviate it have been envisioned. The first involves diminishing the use of plastics markedly, collecting plastic trash for reuse, and if the material cannot be reused, burning it. Burning plastic is virtually the same as burning oil, since currently virtually all plastics are made of oil. Thus, burning the plastic trash diminishes the need for oil and thus diminishes its consumption. This way of addressing the plastics problem is tedious, demands a lot of work and time, and requires a change in our daily behaviour. 

The other solution is much simpler. Let's just find a micro-organism, which uses the plastics as an energy source. The evolution of micro-organisms is rapid as a result of their short generation interval. There are both some bacteria which use oil as food and some fungi which decompose plastics. An example of the latter has recently been described in the journal Environmental Pollution (Khan et al. 2017 Environmental Pollution 225, 469-480). Notably, oil-eating bacteria have successfully been used to clean up oil-contaminated soil, so what is simply needed is to have plastic-eating micro-organism placed within plastic trash, and the microbe does the rest. Simple and effective, right?

However, the solution is not so clearcut beneficial. Our world today uses plastics in virtually everything. Already in the beginning of 1972 a book with the name Mutant 59: The Plastic Eaters was written by Kit Pedler and Gerry Davis. In the book, a mutant bacterium was generated (to remove plastic contamination), but it got loose and started eating up, e.g., the plastic covers of electrical wires with the consequence that electrical appliances short-circuited, planes crashed etc. No one can guarantee that the plastic eating micro-organism cannot spread outside of where it is wanted, unless the evolution of organism is directed so that it cannot live anywhere but its wanted target. For example, one could generate the plastic-eating micro-organism so that it is strictly anaerobic, whereby it would die immediately upon contact with air.

However, for developing the plastic-eating anaerobic organism time is needed. Thus, we must primarily use the tedious first alternative.

Recycle

Maanantai 21.8.2017 klo 14.00 - Mikko Nikinmaa

When I was a child all the cloth, paper and glass were recycled. From then on one changed from reuse culture to culture wasting materials. As a result, we are using in half a year what the earth can tolerate for one year. Environmentally thinking, our wasteful ways should be over.

Wasting materials has been the cheap alternative largely because the long-term damage to and costs incurred by the environment have not been part of any economic calculations. For example, the gross national product does not take into account, e.g., the water pollution caused by industrial production. For this reason, paper and pulp mill directors said in 1970s that: "One cannot build effective wastewater treatment plants, since our products will then become so expensive that they cannot be sold". If environmental damage had been part of economic calculations, that would not have been the case.

But from wasting to recycling. There are already examples, which show that recycling can function. In Finland we have returnable bottles and aluminum cans. As the result, at least 95 % of drinking bottles are returned. Glass bottles can then be washed and refilled. Aluminum cans are pressed, and new cans can be produced. Plastic bottles can also be washed and refilled. Most paper is reused. One is paying recycling fee when buying tyres - the old tyres are then used, e.g. on road surfaces.

For some reason the recycling of cloth has been all but forgotten. This is surprising, as the treatment of cloth so that fibres could be reused is not more expensive than making cloth from native cotton plants, and would be more environmentally friendly. It would just require a change of attitude. Also, reusing all the metals would markedly diminish the need for mining and associated activities. Again, it would not be more expensive, but would need new way of thinking.

All in all, in much of advocating recycling, we are not talking about things becoming more expensive, but about a change in attitude. Recycling needs to be done not because we are poor but because it helps to give our children a habitable planet.

Physiology - the centre of environmental research

Lauantai 6.5.2017 klo 15.43 - Mikko Nikinmaa

As I am again reading a grant application on conservation biology, I started thinking what is important when combining environmental changes and organisms. And the single factor is physiology (=function). This conclusion may be surprising, as physiology is virtually always at least in Finland considered to be a minor field of biology with little importance in environmental science. However, I hope that the points I make below will convince the reader about the truth of the conclusion.

First, without functions organisms would be just stones. They could  have exactly the same molecules, including the whole genome, but if they would not function (=be physiologically active), they would be just unliving material with interesting molecules.

Second, environmental changes will influence the ecosystem only if the function of some organism(s) in the ecosystem is affected. Thus, any ecological effects are only seen after  there must be physiological effects. It is possible that one does not see any change in, e.g., species abundances or composition, even if the environmental disturbance is affecting the physiology of organisms, provided that immigration/emigration balances the disturbance. Consequently, environmental changes can be observed first at the physiological level; physiological changes may cause measurable ecological effects.

Third, even if environmental changes affect the genetic makeup of organisms, the changes are only important, if the physiology of the organism is affected in such a way that the fitness of organism (taken as the number of sexually mature offspring produced) is influenced. Thus, also genetic effects of environmental changes are only seen, if changes in the physiology of organisms take place.

As a conclusion, physiology should be in the centre of biological environmental research. This has already been realized in some cases in USA: I recently participated in filling a position of conservation biology, where a physiologist was selected instead of other biologists. I hope that in this regard Finnish science would be among front runners in noting how environmental biology should develop.

Climate Bandits

Maanantai 3.4.2017 klo 13.18 - Mikko Nikinmaa

In these blogs I have earlier been critical of president Trump's actions. However, recent news indicate that he has a brother in Putin. Putin is also of the opinion that man is not responsible of climate change, and said that increased temperature is an opportunity, not a threat to the arctic environment.

It is a pity that the leaders of two major countries live so much in the past. Fifty years ago the situation was not as bad as now, but Putin and Trump cannot see to the future problems, they only see that doing things as in the past would be the way to go forward.

Ecotourism - can tourism ever be ecological?

Keskiviikko 18.1.2017 klo 12.30 - Mikko Nikinmaa

During recent years something under the name ecotourism has been the most rapidly increasing trend in tourism. The name has been used of all kinds of trips when the destination has been outside the normal tourist attractions and the object has been to visit some nature site. Thus, in many cases for example cruises to Greenland and Antarctica are advertised as ecotourism. In those instances it is easy to say that the travel is far from being ecological. In the easily disturbed Arctic and Antarctic ecosystems such cruises are already one of the biggest causes behind environmental contamination.

Similarly, safari tours to see the big game in South Africa are named ecotourism. While every effort can be made to diminish the disturbance caused to the animals, the mere approach is more or less the same as the reason for creating zoos. Actually, in my opinion the major difference is that when zoos were founded, a normal person could not travel to the places where the animals live in their natural environment, whereas with affordable air traffic it is possible today.

Ecotourism is defined as "responsible travel to natural areas that conserves the environment, sustains the well-being of the local people, and involves interpretation and education". There are two things that make ecotourism, in my opinion, impossible. The first is that the sites can be reached only by, e.g. air or boat transport (and local car transport) which generate fossil fuel pollution. The second is that if a nature site becomes popular, environment will be necessarily affected.

There are, however, a couple of very good things which result from nature tourism (note that I use this word pair instead of ecotourism). The incentive for governments to save the habitats with tourist interests increases. The local people can get the financial benefits from the tourists.

In any case we are not talking about ecotourism, because tourism cannot be ecological, but nature tourism, which can have beneficial effects in addition to the negative environmental effects that tourism necessarily causes.