This is a strange term that I have heard the uninformed use (politicians, for example) about GM foods. However, on reading an article by the biologist Dr Mae-Wan Ho (certainly not an example of an uninformed commentator) it cropped up again. Admittedly, in the middle of phrases like 'Are we nearer to cloning human beings? and 'giant, faceless multinational corporations will control every aspect of [our] lives' it doesn't look out of place. What, though, does it mean?

Apart from the emotive images it evokes, consider what happens when a 'foreign' gene (say an antibiotic resistance gene) escapes from a crop plant. A bee takes up the pollen of the plant and the gene jumps into the bacteria in the bee gut. What then; the gut bacteria become resistant: the bee dies: multinational companies collapse?

It is definately true that we don't know what will happen, any more than we can predict the evolution of the bee. Chemical pollutants are usually only damaging because of the high concentrations, not because they are intrinsically dangerous. Genes are only dangerous if they make dangerous products (although unknown epigenetic effecs are possible) and even then, they have to be expressed. There are important dangers related to transgenics, such as accidentally producing diseases. Labelling these dangers 'pollution' is, however, deliberately co-opting language loaded with inappropriate meaning and symbolism.

The article I refer to is:
'The Unholy Alliance'
The Ecologist, Vol.27, No.4, July/August

Thankyou, amoebius, I appreciate considered argument (IE: informed, I am not elitist about Science, I hope). Perhaps it is no more than a linguistic quibble; it genuinely confuses me though, possibly because I cannot imagine adverse effects from spreading genes. This could well be due to a lack of imagination though! :-)

Chemical pollutants do affect the equilibrium (or rather the steady state) of a living system, just as O3 is necessary in the troposphere but deadly at ground level. Ozone 'fits' into the equilibrium system above the clouds, but doesn't fit into the life on the surface. The point I wanted to make with Oxygen was the world's first pollutant was not the spurious argument I have sometimes come across - that the world will somehow adapt to global pollution - but simply that you cannot attach 'good' or 'evil' labels to chemicals from experience. Ironically, of course, the anaerobes did survive and probably outweigh us (the deep hot biosphere).

Anyway, enough chronology. Linguistically, ther are two meanings of the word 'pollution'. One is the definition you give, the other is what you condemn Monsanto for. If I pollute your beer with vodka I am not poisoning you - but if I pollute your water supply with cyanide you will die. One is introducing something you don't want the other is deadly. Since you dislike 'foreign' genes, my spraying GFP vector all over you is the vodka/beer meaning. Injecting you with HIV virus is the drinking water/CN(I hope you aren't taking offence with these examples, but pollution is a serious issue). Viruses arent GM crops you say? Well, my point exactly - the only way a gene can spread and reproduce (the genetic equivalent of pollution) is by virus or other infectious agent.

Summarising, I am emotional about pollution, which is why I dislike the misuse of the word. Genetic pollution, if you must use the term, can only be virus spread. This is possible, especially with the prospect of biowarfare, but it's not the same as 'natural' cross pollination (what's unnatural cross pollination?:). A chemical pollutant is something that has a polluting concentration (20% ATM for O2 but microgram quantities for PCBs). A genetic pollutant also has a polluting concentration, but not in terms of copy number but promoter strength. Talk of 'overarching networks' is too vague - if something goes wrong in my body, you will not be affected (unless you eat me, as with BSE). If crop plants cross pollinate, the plant will either thrive or die. No 'life support system' s crash will result unless large numbers of plants die.