Monday, March 16, 2009

Oil spills - Double threat to fish

When we talk about oil spills we usually think of marine oil spills where oil is released into the ocean or coastal waters. Oil spills take months, sometimes even years to clean up, and have extremely negative environmental impact to different marine ecosystems. Oil spills are usually cleaned by detergents, and while this indeed may really be the best way to treat oil spills in the long term it is still environmentally unacceptable because it increases its toxicity to fish, making it even more harmful.

These were the results of the latest study carried out by a new Queen's University where biology professor Peter Hodson and his associates found out that though detergents are best way to treat oil spills in the long term because the dispersed oil is diluted and degraded it is completely different in the short term where detergents increase the bio-availability and toxicity of the fuel to rainbow trout by 100-fold.

Basically detergents decrease the surface tension between oil and water, allowing floating oil to mix with water as tiny droplets. This dispersion reduces the potential impacts of oil on surface-dwelling animals, and also creates a larger reservoir of oil in the water column. So what this has to do with fish population? Fish population problem in this case is called hydrocarbons. Use of detergents increases the transfer of hydrocarbons from oil to water enabling hydrocarbons to pass easily from water into tissues and these hydrocarbons are deadly to fish in the early stages of life. If oil spills become more frequent this could have serious negative impact on health of fish populations.

What this study really showed is how deadly dispersed oil actually is to fish population, and that cleaning oil spills is in fact double blow to fish population. Of course once oil spill happens it has to be treated but unfortunately cleaning process also has additional negative impact on fish population. The best thing would of course be to prevent oil spills from happening but this is sadly only possible in theory.

No comments:

Post a Comment