Meet EVAThe Pollution Preventers have learned that it is an increasing challenge to sample water for contaminants at an inexpensive cost. Water quality sampling is typically done through grab sampling at single or multiple points in the water. However, the problem with these approaches is that they provide a snapshot of water quality is space and time- therefore the measurements are subject to variability which could impact the concentration of the contaminant at the time of sampling.
Recent technologies have been introduced that proved a way to measure pollutant levels over a longer time frame and average the concentration of pollutant over the period the sampler is deployed. These are called passive samplers. Passive samplers work by providing a substrate that has been infused with reference compounds that correspond to pollutants that are targeted for measurements. When passive samplers are deployed, they equilibrate the pollutants in the environment with the receiving marker over a period of time to provide and averaged concentration of the pollutant. One of the compounds used as a passive sampler is Ethylene Vinyl Acetate (EVA). Ethylene Vinyl Acetate has been identified by Dr. Penny Vlahos at the University of Connecticut. EVA is the compound that the Pollution Preventers are using to identify contaminants in Lake St. Clair as well as Lake Erie. |