Pesticide use has increased dramatically worldwide due to the rise in the global population. More people means that more food is needed for survival, and pesticides are used to grow this food efficiently. Most significantly in tropical regions, pesticide use has also increased in order to supply a larger crop. Although it is disputed that pesticides are essential in modern agriculture, there is a growing concern about the possible environmental contamination of waterways. Within the last 25 years an intensive agricultural industry has developed in the northern region of a state in Brazil, which involves frequent pesticide use. A recent study has found that 68% of water surface samples and 97% of rainwater samples in southern regions of the state contained traces of the pesticide used in the northern region.
This study concluded that there were traces of pesticides present in waterways far from the application site. Drinking water is already scarce in some regions and this will reduce it even more. What will the effects of these pesticides be? One of the authors of this paper, Volker Laabs says “The measured river water concentrations of pesticides were substantially lower in our study area than in the Midwestern USA.” This could suggest that the application of pesticides may have an even greater effect in the USA. Do we know if our drinking water contains some traces of pesticides?
Significant amounts of suspended sediments were detected downstream of the main application sites, while very little were found farther upstream in several of the streams and rivers studied. The concentrations of pesticides detected in the studied streams were below the maximum contaminant levels of pesticides established for drinking water by the USEPA (2000). It was also noticed that there was a smaller number of pesticides found in river water than stream water, however this has been attributed to dilution effects. The team found that pesticides were detected in 97% of all collected rainwater samples, with up to 9 pesticides detected in 1 sample. Halfway through the study period the application (by plane) of a pesticide in cotton fields began, leading to the detection of this pesticide in rain samples almost immediately. The process of contamination of waterways doesn’t take time to occur, it is an immediate action-reaction process.
The results presented in this study suggest that the application of pesticides in the tropics has a great effect on nearby water sources. Noticeable concentrations of the applied pesticides had been detected in both rainwater and surface water samples of streams and rivers nearby. It is very important that we consider the use of chemical applications in agriculture, as it has been proven that it disturbs the aquatic ecosystems in the tropics. If pesticides have a proven role in the tropics, we have to wonder about their effects here in a more temperate climate. Hopefully our drinking water is actually safe to drink.
Amelung, W., Laabs, V., Pinto, A. &, da Silva, C. (2009). Pesticides in Surface Water, Sediment, and Rainfall of the Northeastern Pantanal Basin, Brazil. Journal of Environmental Quality. 31:1636-1648. Received 2009 October 10, from, http://jeq.scijournals.org/cgi/content/full/31/5/1636
Well put together, it felt like a real newspaper article. I like the use of numerical facts. But if we don't use pesticides to remove pests from our crops, then would making GMOs make a difference?
ReplyDeleteI really liked your opening paragraph and how you used stats to inform the reader of what is happening. This was very informative and very interesting.
ReplyDeleteI think this blog is well written and well organized. I liked how you summarized the primary article into a newspaper article. You had enough information to understand the study and not to technical. Great job.
ReplyDelete