Publication date: November 22, 2000
Toxic intensities and risk for 246 Toxic Release Inventory (TRI) chemicals. Similar to the IPPS data, these intensities can be used to estimate toxic chemical load given employment, value of output, or value added.
The ToxInt database has been produced by the World Bank's Economics of Industrial Pollution research team, in collaboration with the Center for Economic Studies of the U.S. Census Bureau. The dataset provides pollution intensities and the corresponding toxic risks for 246 chemicals in the U.S. EPA’s Toxic Release Inventory (TRI).
The following variables are provided:
- the chemical name,
- a standardized chemical identifier called the Chemical Abstract Service (CAS) number (denoted in the tables as NCAS),
- 4-digit ISIC codes,
- pollution intensities for air, land and water by employment (E), value of output (T) and value added (V), and
- Threshold Limit Values (TLV’s).
The units of measurement for employees are kilograms per 1,000 employees, and for value of output and value added, the units are kilograms per 1987 $US million.
The database used to determine pollution intensities is the same database used from the TRI to generate the Industrial Pollution Projection System (IPPS). All the pollution intensities represented are lower-bound. To learn how lower-bound pollution intensities were calculated, please refer to Section 3.2.4, "Alternative Estimates of Sectoral Pollution Intensity" of the The industrial pollution projection system. (Please also note, Section 4, Construction of a Toxic Risk Pollution Intensity Index of this paper represents an unrelated risk weighting methodology.)
TLV’s are measures of safe toxic exposure levels, as determined by the American Conference of Governmental Industrial Hygienists (ACGIH). They are time-weighted average concentrations in air that cannot be exceeded without adverse effects for workers in a normal 8-hour work day and a 40-hour work week. TLV’s are updated annually by the ACGIH. This data uses 1996 values.
All TLV’s units are in milligrams per cubic meter. In cases where no TLV measurement is provided for a chemical, it is because no guideline had been provided by the ACGIH. Also please note that not all toxics are released by plants in all sectors, so that for a particular toxic, the omission of a sector row implies zero output of the toxic from that sector.
On a Practical Note
The IPPS project has aimed to establish initial benchmarks of pollution intensity and toxic risk in manufacturing sectors in the developing world. We have always assumed that further and more detailed analysis would refine, and in some cases alter, these first-order attempts to understand magnitudes of environmental degredation and health risk. Some colleagues in academia have expressed concern about the IPPS's reliance on acute toxicity measures to the exclusion of chronic toxicity measures, and its use of mass-only measures to identify environmental risk by chemical. For our part, we believe that IPPS should be viewed as a useful tool, rather than a final answer, for those involved in international risk assessment work.
The U.S. EPA has also been seeking to incorporate chemical risk assessment into its project work. The EPA maintains an Integrated Risk Information System (IRIS) database on human health effects that may result from exposure to various chemicals in the environment. IRIS was initially developed for EPA staff, in response to a growing demand for consistent information on chemical substances for use in risk assessments, decision-making and regulatory activities. The information in IRIS is intended for those without extensive training in toxicology, but with some knowledge of health sciences.
EPA's Sector Facility Indexing Project (SFIP) provides another approach to risk assessment. The SFIP couples emissions data from the Toxics Release Inventory (TRI) with toxicity weighting factors. The result is an index which accounts for both emissions volume and risk in assessing toxic pollution. On April 29, 1997, a Subcommittee of the EPA's Science Advisory Board's Environmental Engineering Committee met to review the technical aspects of the SFIP. To learn more about this and other aspects of the EPA's current work on chemical risk, please visit them at http://www.epa.gov/science1/pifs.htm.