Moving towards safer alternatives
SUBSPORT - SUBSTITUTION SUPPORT PORTAL > Substitution Tools > Pollution Prevention Options Analysis System (P2OASys)

Pollution Prevention Options Analysis System (P2OASys)

» Back to List

1. Elaborated by

Toxic Use Reduction Institute of Massachusetts (TURI)

2. Description

P2OASys was designed by the Toxic Use Reduction Institute of Massachusetts (TURI) to provide companies with a framework for complete and systematic evaluation of potential hazards of processes and products in use and of alternatives.

The tool can be used in two different ways:

  1. To systematically examine the potential environmental and worker impacts of toxic use reduction (TUR) options in a comprehensive manner, examining the total impacts of process changes, rather than simply those of chemical changes; and
  2. To compare TUR options with the company’s current process based on quantitative and qualitative factors.

P2OASys can be used to analyze technological processes, individual chemicals or chemical mixtures. It arrays data on a range of hazards, including acute and chronic human health effects, environmental concerns, physical and chemical hazards such as flammability and reactivity. Exposure potential is estimated as low, medium or high. The process or chemical under evaluation receives a score for each type of hazard that indicates very low to very high risk.

P2OASys uses the “max-min” principle, meaning that the highest value within any hazard category dominates that category of analysis (e.g. chronic toxicity, acute toxicity, etc.).

Users must begin by filling in the data for the technology in use in a spreadsheet. Users must also input a certainty factor between 0 and 100 that indicates the user’s level of trust in the provided values. If the technology in use is a mixture of substances, information for each component must be added. P2OASys converts data for each hazard category into a numeric scale (0 to 10) with the lowest score representing a lower hazard and the highest score representing a higher hazard.

Users must fill in similar sheets for each alternative that they want to compare with the technology in use. The Comparative Scores Worksheet collects all of the Scores and Certainties from the different technology alternative worksheets. Afterwards, the Hazards worksheet collects the Scores and Certainties from all of the categories of the current and alternative technologies and allows the user to compare them against each other.

Hazard categories evaluated by P2OASys include:

  • acute and chronic human effects
  • physical and chemical hazards
  • atmospheric hazards (ozone layer depletion, greenhouse effect)
  • aquatic toxicity
  • waste generation
  • energy/resource use
  • product hazard
  • exposure potential

This method includes a database with over 2000 hazardous properties for 778 substances. The main source of information is the National Library of Medicine’s ToxNet. Users must also put in certain specific indicators for the process as noise generation, psychosocial hazards and energy/water use.

Values cannot be added up to get a final result due to the use of different kinds of data (quantitative, semi-empirical and qualitative) from multiple sources. The final interpretation of comparison is left to the user.

3. Reliability

This is a very reliable method due to the variety of indicators it examines and the use of solid sources of information as the National Library of Medicine’s ToxNet database.

4. Applicability

It can be used to compare products, processes and technologies. It takes in account other environmental and health hazard and risks, not only chemical. Most suitable for companies with professional expertise.

5. User friendliness

This tool is not easy to use. It requires expertise and dedication to obtain all the information about the different indicators.

6. Limitations

Access to the required information is difficult. There is not one single database or source providing the necessary data. Not suitable for SME and consumers.

7. Availability

P2OASys is available as a downloadable spreadsheet at the TURI website. There is also an online interactive format that requires payment.

8. Links

Go to: P2OASys at

» Back to List

Restricted and priority substances database» link
Case story database » link

External substitution websites and databases
Logo Grontmij Logo Istas Logo Chemsec Logo Kooperationsstelle Hamburg