Alternative Risk Assessment Methodology

Project background

A variety of state and federal agencies monitor for a wide range of contaminants in Minnesota waters, including chemicals from pharmaceuticals, personal care products, and household products. Many of these chemicals are categorized as contaminants of emerging concern (CEC). When a contaminant is found in water it raises the question of whether the level found poses a potential health risk. The Minnesota Department of Health (MDH) is tasked with determining human health-based guidelines for drinking water. Traditional methods for developing these guidelines require toxicity information specific to each contaminant. Unfortunately, this information is available for only a fraction of the contaminants used in industrial and commercial applications in the United States. Currently there is no standard method for evaluating the potential health risks for contaminants that do not have toxicity information. The goal of this project is to discover methods that can create health recommendations for contaminants with little or no toxicity information.

Project details

There are two phases to this project; the first phase has been completed and the second phase is on-going. The focus of phase one was to identify alternative risk assessment methods that would work for contaminants with little or no toxicity information and conduct basic testing on these methods. A scientist was hired as a contractor to conduct this work. Ten possible methods were identified. After basic testing, five of the ten methods were selected as methods that might be useful in creating health risk recommendations. Based on these results, MDH scientists created a draft decision framework that is based on a combination of available toxicity information and predictions of health effects for a contaminant. An Executive Summary (210 KB/17 pages) of the 2012 final draft report for phase one is available for download. The full final draft report (2,565KB/251 pages) is also available upon request by emailing
The second, on-going phase of this project involves conducting expanded testing of the methods selected in phase one, both as individual methods and as a group of methods that work together. The contractor for phase two also identified and tested additional analytical methods developed since the completion of phase one. The draft decision framework is undergoing revision and testing for how well it performed in providing health risk context for a variety of contaminants and a variety of health effects.

Project applications

With this project MDH will:

  • Discover methods that could create health recommendations in a rapid and reliable manner for CECs that have little or no toxicity information.
  • Advance scientific and policy discussions regarding alternative risk assessment methods for contaminants with limited toxicity information.
  • Expand the number of methods that can be used to assess CECs.
  • Create a pool of staff that have the knowledge to select the appropriate method to assess a certain CEC.


Updated Wednesday, December 31, 2014 at 11:19AM