Why do herbicides affect animals?

Maanantai 17.10.2022 klo 16.50 - Mikko Nikinmaa

The development of herbicides has long concentrated on finding molecules that affect biochemical pathways not present in animals. As a consequence, it has been considered that they do not cause harm to insects and vertebrates. Studies on animal cells have usually confirmed this supposition: since the biochemical pathway is not present, the compound is not toxic to animals.

Because of this, the increasing number of findings suggesting that herbicides have toxic effects on animal populations have largely been labelled as trash. This conclusion does not, however, take into account that the animal body has more microbes than body’s own cells. The animal’s microbiome, as it is called, influences nutrition, humoral and immune functions, metabolism and even neural behaviour. Many microbes in our body have the biochemical pathways targeted by the herbicide molecules. Consequently, herbicides affect the species distribution of microbiome, whereby the functions affected by the microbiome can also be influenced in animal body, and the herbicide be toxic to animal.

In recent review by Ruuskanen et al. in Trends in Ecology and Evolution (doi.org/10.1016/j.tree.2022.09.009) give a detailed description of the role of microbiomes in shaping the responses of non-target organisms to herbicides. An important point to note is that the sensitivities of organisms that are susceptible vary markedly. Also, the speed by which resistance is developed is highly variable. Further, the fact that different conclusions are reached if animal cells or whole animals are used in the studies casts significant doubt on the animal protection thesis that instead of intact animals, cell cultures should be used in toxicological studies.

Intensive agriculture is a crisis to nature

Keskiviikko 4.5.2022 klo 17.18 - Mikko Nikinmaa

For a long time intensive agriculture was considered to be just a blessing to the humankind. The farm yields increased everywhere in the world thanks to the use of pesticides and artificial fertilizers. The fear-mongering about population bomb seemed completely unfounded. Intensive agriculture could easily feed ten billion people.

This rosy dream was true as long as there were refuges for pollinating insects in areas not treated by pesticides, as long as the agricultural land remained uneroded and as long as new agricultural land had the same quality as the earlier soils. Unfortunately, none of these premises hold true any more. A recent report in Nature (Outwhaite et al.  https://www.nature.com/articles/s41586-022-04644-x) shows how climate change and intensive agriculture reduce insect populations throughout the world. It is actually quite natural that the heavy use of insecticides causes insect populations to be reduced markedly, since the poisons cannot differentiate between beneficial and harmful insects. Now that there are not enough refuges, where the beneficial insects could breed to restore the populations in agricultural areas, they are decreasing quite rapidly.

Up to three quarters of plant material we eat needs insect pollination. Because of this, it is very funny that especially agriculture lobby groups have been strongly against banning of some insecticides. The short-term gains markedly outweigh the yield losses which will happen in longer term. I bet that the agricultural sector which has been against banning insecticides then screams for subsidies as pollination fails.

Another problem in addition to pollination problems is that the methods used in agriculture slowly decrease the fertility of the soil. To avoid fertility losses the fields should always be plant-covered. It would also make the fields carbon dioxide sinks throughout the year. Now they are probable carbon dioxide sources.

All in all, human race is using an increasing percentage of land area, and a large part is used for habitation and roads. This use is the worst possible for sustainability and therefore should serve as a strong reason to have population control as an important component of climate actions.

Why we need to change from intensive to environmentally friendly sgriculture

Torstai 12.11.2020 klo 19.23 - Mikko Nikinmaa

Intensive agriculture has relied heavily on ploughing and harrowing, fertilization and the use of pesticides. As a result, it has been possible to increase yields so much that whereas in 1960’s one was considering 5 billion humans to be maximum for feeding, there are now about 7.8 billion of us. Further, the absolute number of starving people has decreased, as the world population has increased beyond 5 billion. A success story? I am afraid not, only a temporary solution, which is currently being reversed: all the aspects of intensive agriculture are beginning to show their downsides. All of them indicate that intensive agriculture as carried out today is not sustainable.

First, soil fertility throughout the world is decreasing. The decrease happens fastest in tropical soils, but also the temperate, long-cultivated soils have recently started to show signs of becoming exhausted. The major reason for the loss of fertility is the fact that present agricultural practises are based on having fields without plant cover for a long period of time. Land without plant cover loses the most fertile topsoil as a result of leaching: if the land were covered with plants, much less soil would be lost when it rains or winds blow. Also, native land is a carbon dioxide sink, but ploughing and harrowing makes it a carbon dioxide source. It would certainly be possible to change agricultural practises to plant-cover requiring ones. To stop the decrease of soil fertility, that should be done. It should also be done, as the soil lost from fields ends up in rivers, lakes and the sea, causing their eutrophication.

To maintain soil fertility, artificial fertilizers have increasingly been used. Mineral phosphate deposits are overused, and much of the fertilization ends up in the aquatic environment contributing to eutrophication of water. To decrease flow of fertilizers into rivers and lakes, protective zones with plant cover are required. However, a much better alternative would be agriculture, which does not involve ploughing and harrowing.

Finally, the use of pesticides, especially insecticides, in copious amounts has been the landmark of intensive agriculture. Unfortunately, pests have begun to tolerate pesticides better and better, which results in increasing pesticide need to maintain efficacy. And this is not all; three quarters of all food crops require insect pollination, and it has clearly been shown that insect populations throughout the world are decreasing. Although definitive cause-and-effect relationships between insecticide use and decreasing population sizes have not yet been obtained, it is quite reasonable to suppose that it is the case. Instead of increasing use of chemical insecticides and other pesticides, biological control of pests has been advocated for the past fifty years. However, even though it would be much more environmentally friendly than the present chemical-dependent pest control, biological pest control has not become the most important way for controlling pests.

Thus, the very points that have been the cornerstones of increasing yields in intensive agriculture are now causing all sorts of problems ultimately leading reduced yields. There are alternatives to the present-day practises, but they require a complete change of cultivation methodology.

Increased temperature is associated with reduced efficiency of insecticides

Sunnuntai 8.3.2020 klo 14.05 - Mikko Nikinmaa

 

When discussing Climate Change, it is often said by people in northern latitudes that an increase in temperature is only beneficial, as plant growth will increase, whereby agricultural production will increase. Even if the temperature increase will cause some parts of the world to become completely unsuitable for agricultural production, the people, who say the above, do not care, as they maintain that it doesn’t matter what happens to the rest of the world, if the situation in their neighbourhood gets better. There are, however, two reasons why a temperature increase may not increase plant production without a marked increase in the use of insecticides. Since their use already affects, in addition to harmful insects, necessary pollinators, the use of insecticides should be decreased instead of being increased. Besides, the agricultural products from northern latitudes are always marketed as containing little pesticides and other exogenous substances. If temperature increases, this is not true any more.

There are two major reasons for the need of more insecticides. First, and this is virtually always mentioned, when the upsides and downsides of temperature increase to agricultural production in northern latitudes are discussed, the number of pest species increases and their populations become stronger. To be able to kill the harmful insects, more spraying of poisons is needed. In fact, one can think of severe winters as effective insecticides, they limit the growth of most pests. Second, and this is seldom considered, the insecticide concentration needed to kill the animal usually increases with increasing temperature. There are a couple of possible reasons for these. The most likely one is that the insecticide is detoxified more rapidly at high than at low temperature: the activity of all the detoxification enzymes increases with temperature. Also the excretion of insecticides is speeded up.  It appears that the neurobiological toxic actions are affected less than detoxification and excretion, because it is probable that also the toxic effects will be increased wit temperature. However, if the toxic action is increased less than detoxification and excretion, the overall effect is that more insecticide is needed for the same effect.

Notably, although the available results suggest that the insecticide concentration needed for a given toxic effect increases with temperature, interactions between abiotic environmental changes like Climate Change and environmental pollutants have been inadequately studied. For this reason our understanding of what causes the reduced effect of insecticides at higher temperature is deficient.

Cotton - always in the middle of social and environmental problems: could it be replaced for the benefit of mankind

Keskiviikko 10.7.2019 klo 12.17 - Mikko Nikinmaa

Cotton clothes, all of us wear them.  However, do we realize all the social and environmental problems associated and the fact that we could presently achieve a cotton-free society which would be a contribution towards combatting climate change, social inequality and environmental destruction?

Initially, the cotton production was a strong component for American slavery. Cotton fields in southern USA needed workers, and they were brought in as slaves from Africa. Although also other forms of cultivation such as growing of tobacco and sugar cane needed workers, cotton cultivation was the most important one, generating rich plantation owners and poor slaves, and later the racial problems in America, which are still a big problem.

The problem with genetically modified organisms really boils down to cotton.  Out of the approximately 32 million hectares, where cotton is grown, approximately 25 million hectares is genetically modified (GM). Consequently, it is my bet that people against the use of GMOs (genetically modified organisms) daily wear clothing that has genetically modified cotton. GM cotton was marketed to farmers saying that the need for pesticides would be reduced. However, that has not turned out to be the case. While the insecticide use in USA and Australia has markedly decreased after the introduction of bt-cotton (a genetically modified plant, which produces its own toxin against several insect pests), the herbicide use has not decreased. In most other cotton-producing countries pesticide use has not decreased, partly because secondary harmful insects require heavy insecticide use to ensure high production. Further, it appears that the difference between pesticide use in large industrial cotton cultivation (decrease in insecticide use) and small cotton farmers (no change or increase in insecticide use) has increased.

 The heavy pesticide use in cotton production is an important component in causing the deaths of non-target organisms. Insecticides kill non-selectively all insects, be they beneficial or harmful. Research on waterways has indicated that agricultural pesticides kill aquatic invertebrates and fish. Often the insecticides are more toxic to aquatic creatures than to their target organisms. Further, it was recently estimated that close to 70 000 000 birds per year die directly because of pesticide use.

Although cotton cultivation does not require very much water (10000 l/kg cotton produced worldwide), the fact that it is grown in dry areas largely for export with the profits going not to local farmers but to big agricultural companies often from foreign countries means that the water use does not support the local people’s food production or water needs. Consequently, the poor people in the dry areas continue to suffer from food and water shortage in India and Africa. Partly the recent trend that food shortage is again in the increase in Eastern Africa could be alleviated by stopping cotton cultivation and using the water for cultivating edible crops.  This, as such, would decrease the number of refugees trying to come to the paradise in Europe.

Production of cotton clothing has also another social problem. In many countries producing cotton clothing cheaply, child labour is used. To best combat this, e.g. European collaboration would be helpful. As the final question one must ask if cotton is necessary as primary cloth material any more. Earlier it was, as all the other fibres that could be used for producing fabrics yielded much harder and therefore less comfortable cloth than cotton. However, recently the situation has changed, and currently wood fibres can yield as soft and comfortable cloth as cotton. Since the need for paper production has markedly decreased, wood could be used for cloth-making.

Replacing cotton with wood fibre would thus be a highly beneficial both socially and environmentally. First, the land and water used now for growing cotton for export with most profits not coming to local people could come completely to help the food and water needs of local communities. This would decrease the refugee pressure to North. Because the pesticide use would be reduced, all the negative issues associated with them would also be reduced. Growing trees for fibre production would not have a negative effect on carbon footprint globally, most likely the opposite, as the life length of clothing is longer than that of paper products. Thus, one would be combatting climate change, whereby the number of climate refugees in the future would decrease. Finally, as the right-wing populists always say that isolationist policies are needed for the success of “our” industry, producing cloth would be a significant new direction to pulp industry. All in all, replacing cotton could be a good example of how thinking globally has positive influence on social and environmental problems in the world.

From cotton to more eco-friendly clothing

Keskiviikko 3.10.2018 klo 20.10 - Mikko Nikinmaa

Cotton is undoubtedly the least sustainable agricultural product. Yet, cotton clothing is used by everyone. The dark sides of cotton cultivation are many. Cotton fields cover large areas of arid landscape and virtually all the water and land are used for producing cotton instead of food in countries, where people are starving. It would not really matter, if the income from cotton sales came to the starving people enabling them to buy food. Unfortunately, this is not the case: typically the income from producing cotton goes to foreign companies or to rich land-owners. Cotton cultivation can be considered to be a reason for the African immigrants trying to cross the Mediterranean Sea to come to rich Europe. Most cotton these days is from gene modified plants. And even people strongly resisting GMOs have GMO cotton clothing. Copious amounts of insecticides and other pesticides are used in cotton fields. Cotton cultivation with its high pesticide usage can be considered as being one reason in the possible decline of insect populations -there is yet no insecticide which would kill only the harmful ones but leave, e.g., the beneficial pollinators intact. In addition to insects, it has been supposed that the heavy insecticide use is the cause of death of millions of birs: birds eat insecticide-affected insects, and get enough poison to be affected, so that their likelihood of death directly because of poisoning or indirectly because of the insecticide-induced alterations in behaviour. There are also reports of much declining bird populations, and the insecticide use of cotton cultivation is a likely contributor to them.

So what kind of material should sustainably produced clothing be made of? After all, we need clothing. Artificial fibres are not an option, since they are normally oil-based, and can be said to contribute to the (micro)plastics problem. That leaves wood fibres. Earlier on their use has not been considered environmentally friendly, because of toxic chemicals, which were needed for making wood fibres suitable for cloth-making. However, the new methods for producing cloth using wood fibre does not require toxic chemicals, and the process can be considered almost fully closed, i.e. virtually no effluents are produced before the final product is in the hands of consumers. The first pilot factories producing cloth from wood with the new methodology are being taken to use. So, compared with cotton: agricultural land is returned to food production, no pesticides are used – thus, the eco-friendly solution, clothing from wood fibre. In the beginning the wood-cloth is probably more expensive than cotton, but regardless should be used by anybody preaching sustainable way of life.

Can we wear any clothes?

Sunnuntai 17.12.2017 klo 17.38

As the "most unneeded product of the year" the nature conservation magazine Finland's Nature chose fleece clothing, because washing them liberates microplastics in water. This got me thinking, which clothes we can wear, because environmental arguments for the discontinued use of virtually everything are strong. Below I go through them in detail:

1. Fleece clothing, but also virtually all other synthetic clothing should not be used, since they inevitably cause the release of microplastics in the environment.

2. Cotton clothing should not be used because of several reasons. It is very likely that the cotton from which the clothes are made is from genetically modified plants (GMO). The use of different pesticides in cotton fields is greater than anywhere else. As a result, the number of dead birds is great because they eat insecticide-affected insects, and the toxicant also affects them. In the semiarid areas, where cotton is produced, cotton production uses up water, which would be needed for food production and human consumption. Further, it is quite likely that the cotton clothing we wear has been produced using child labour, at least if we want to have cheap models.

3. Wool products should not be used, because wool clothing is produced by taking advantage of sheep. If one is protecting the rights of animals, that is not acceptable.

4. For the same reason as for banning wool products, everything containing leather or fur should not be used, because they can only be produced, if animal rights are not respected.

So what can we wear? Presently only linen clothing, but if it becomes popular, it is likely that many of the problems associated with cotton will also take place in linen production. Wood fibres could be a solution, but many hard-core environmentalists are also against the use of wood products. I suppose I shall start to look what the real environmentalists wear to see, if they follow their principles. - Or maybe we should walk around naked? It would also be difficult here in the north, when temperatures are close to or below freezing.

Poorly known addditives may be more harmful than glyphosate itself

Torstai 22.6.2017 klo 10.31 - Mikko Nikinmaa

With the discussion about the harmful effects of glyphosate on tends to forget that the additives in the different commercial formulations may be more harmful to non-target species than the main toxic ingredient. It is undoubtedly true that the persistence of glyphosate in soil in different climatic zones is poorly known, and because of the antibiotic properties of the compound, knowing this would be necessary to be able to estimate the effects of the toxin on the community functions of soil micro-organisms.

However, for animals the additives in the commercial formulations are the real problem. The additives are a commercial secrecy, but an example of their importance in mediating at least acute toxic effects in non-target animals comes from a recent study: pure glyphosate and one commercial formulation showed negligible toxic effects, whereas another formulation was acutely highly toxic. Since the additives are a secrecy, the properties of the compounds used cannot be studied, since the compounds in question are not known.

Two things should generally be noted about glyphosate and its formulations. First: because glyphosate is affecting pathways specific to autotrophic organisms, it has not been considered important that the effects of its commercial formulations are studied with non-target animals. And because the additives are a secrecy, even if the effects on non-target animals are studied, one does not know the toxic compound. Second: the chronic effects of the main toxic ingredient and additives have not been investigated at all on non-target animals. Because of this, there are wild, and completely unsubstantiated, rumours about the harmful effects caused.

Happy New Year?

Lauantai 31.12.2016 klo 11.31 - Mikko Nikinmaa

Hopefully the new year 2017 will bring forward good things for the environment. There are many possibilities - new approaches just require that we are not stuck in old ways of thinking.

I give just one example. Many people are concerned with gene modifications. Yet, the same people use cotton clothing; the likelihood that gene-modified cotton has been used for making cotton clothes is overwhelming. In addition, the use of pesticides in cotton cultivation is very high, meaning that the use of cotton clothing probably causes the deaths of millions of birds which eat contaminated insects. Further, cotton production uses both water and space, which would better be used for food production. So, all these things urge us to change from cotton use to something new...

We already have the possibility to change to the something new. It is possible to produce cotton-like threads from the long-fibred fir trees. Now that paper use is in decline and pulp industry is probably environmentally the most advanced, changing from paper as the major product to cloth would be both feasible and environmentally friendly.

Such change would be possible, but would require consumer pressure. If the consumers demand a change, that will happen (albeit slowly). We were able to stop acid rain in Europe, eeven though it required expenses. So why should we not change from cotton clothing to tree fibre-based clothing, as it is an environmental advance with little cost?