Last week Duluth Parents for Healthy Playgrounds presented the results of a test conducted by St. Paul-based Legend Technical Services on a sample of rubber mulch from the playground at Lester Park Elementary School. The test found 12 chemicals listed by the Minnesota Department of Health as “chemicals of high concern,” but the chemicals were at levels not considered hazardous.

From the report’s executive summary:

Our test does not account for possible interactions or “synergistic” effects of the 12 “chemicals of high concern,” nor for carbon nanotubes. Given the variety of chemicals different tire manufacturers use, and the variability of the tire brands in Rubberific mulch, the eight grams from Lester Park Elementary that were tested may account for only a few of the estimated 12,000 tires in the whole playground.

Link to the full report: Scrap Tire Mulch on Duluth Public Schools’ Playgrounds (PDF)