Have you ever spent the day walking through the woods, paused to take in the natural sights, smells and sounds of a babbling brook or flowing waterfall and thought….“I wonder how many pesticides are in that water?”
I recently experienced this when I escaped from the stress and chaos of real life to spend a day hiking through the woods. I mapped out my route, packed plenty of snacks and water, and tossed my camera (i.e. my iPhone which has a camera) into my backpack, and I was off. I wasn’t far into my hike before I heard the familiar rush of moving water. Excited at the thought of finding a natural stream or brook, I rushed toward the noise until I reached the edge of a bank that overlooked a flowing river. As I took in the breath-taking scenery, I found myself lost in thoughts like “I wonder how polluted this water is?” or “I bet there are pesticides in this water. Is it safe to drink?”
Pesticides – in both organic and synthetic forms – have been used for decades, primarily to protect our crops from harmful pests and diseases. One of the early compounds developed was dichloro-diphenyl-trichloroethane, more commonly known as DDT. This chemical quickly became popular for use because of its success in protecting crops and livestock against a range of diseases, including malaria and typhus. DDT is one of many chemicals that have been used as herbicides, pesticides and insecticides over the past several decades, in an attempt to preserve some of our food resources.
In the 1970s, pesticides were monitored for potential health effects to humans and animals. Their widespread use created the potential for contamination from spills, leaks, improper disposal, and rain runoff; however, the belief was that soil would act as a filter and prevent pesticides from reaching aquifers and groundwater sources. Instead of acting as a barrier and blocking contaminants, we now know that soil absorbs contaminants and leaches them into the surrounding water sources.
In 1991, Congress formed the National Water Quality Assessment (NAWQA) to monitor what we do and how our activities impact (or could impact) our water quality. The group has since started gathering data to monitor the nation’s water quality, as well as resources to protect and improve our precious resources. Data collected by this group has allowed them to build occurrence and toxicity maps to assess potential risk in various geographic regions. In order to properly monitor and document this health risk, water samples must be properly collected and the chemicals must be carefully extracted, separated, identified and quantified. Interested in learning more about this quantification process? Here are some relevant app notes to provide guidance and detail.