Developing analytical environmental forensic techniques to identify new persistent and bioaccumlative chemicals

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Over the last ten years, there has been a significant increase in the manufacture and use of man-made chemicals. One study has estimated that there are 4 000 new chemicals produced each day. Many of the chemicals produced by industry are used in commercial products that we use or encounter on a daily basis. For example, flame-retardants are added to foam materials used in couches, mattresses and chairs to mitigate the spread of fires. These chemicals are typically not bound to the end-product, and over time are released from the intended product. Research indicates that the subsequent release of these additive chemicals can result in direct human exposure. Furthermore, leaching of additives from end-products in land-fills can contaminate aquatic systems and organisms therein. Our understanding of the chemical environmental behavior of many chemicals used for commercial purposes is lacking primarily because new analytical methods to detect and identify these compounds are not available. In addition, the potential threat many of these chemicals pose to humans and wildlife is largely unknown. This proposed research will address some of the many data-gaps that currently exist. First, we will develop novel analytical techniques to identify chemicals in commercial use that to date have gone unreported. Our focus will be on those chemicals that are suspected to be a concern because they are persistent, toxic, and accumulative in higher organisms. We will employ a variety of separation and mass spectrometric detection techniques to isolate new and previously unreported chemicals and to identify their chemical structures. We strongly anticipate our research will lead to new chemical discoveries. We will also test the inherent toxicity on a judiciously selected sub-set of identified chemicals by using a fish bioassay that we are pioneering in our laboratory. Specifically, our toxicity studies will examine the impact exposure to these chemicals have on the production of sex hormones in fish. Our results will also contribute significantly to fundamental physical properties and toxicity reference databases employed by risk-assessors to model the behavior and toxicity of chemicals of emerging concern. Our expected results will provide the crucial scientific evidence required for national (Environment Canada) and international (Stockholm Convention) regulators to make sound regulatory decisions on the production and use of anthropogenic chemicals. Analytical advances made in our laboratory on the detection of new and previously unreported chemicals will benefit such agencies in aiding them to fulfill their mandates.