Degradation
The chemical, physical and/or biological process which leads to disintegration of the plastic.

Degradable Plastic
A plastic designed to undergo a significant change in its chemical structure under pecific environmental conditions resulting in a loss of some properties that may vary as measured by standard test methods appropriate to the plastic and the application in a period of time that determines ts classification.

Toxicity
The effects of industrial and agricultural chemical on the environment is a concern by the scientific community and the general public.  Immediate and long-term effects on the biomass of the soil, ground water, and on the up-take of elements into the plant mass must be checked...The first stage of degradation shows film being reduced into a fine powder, which is totally inert and physiologically harmless to man, animals and to plant life.  As the break-down continues, which is irreversable, the molecular long-chain structure of the polymeric material shortens.  The molecular weight reduces continually until the polymer is returned to simple compounds such as water and carbon dioxide.

Toxic substances are not produced in this process...Biodegrading activity is summed up as follows:

• •  photo oxidation
• •  thermo oxidation
• •  hydrolysis
• •  microbiological attack
• •  humus-like mass incorporated into the soil

WRP's prodegradant additives causes surface erosion of the polymer.  This produces activated oxygen which is reabsorbed into the polymer, thus accelerating the oxidation process.  Certain microorganism feed on the break-down products of the oxidizing polymer.  The dead and living microorganism and the polymeric substrate develop into a humus-like mass, which is ultimately incorporated into the soil.