ASTM International

Standard Test Method for Determining Aerobic Biodegradation of Plastics Buried in Sandy Marine Sediment under Controlled Laboratory Conditions
 N D7991

Annotation

This test method determines the biodegradation level of plastic materials exposed to laboratory conditions that simulate the environment found in the sandy tidal zone.

The tidal zone, that is, the part of the coast affected by the tides and movement of the waves, is the borderline between sea and land, frequently a sandy area that is kept constantly damp by the lapping of the waves. Stony and rocky shorelines also exist.

Plastic marine debris is frequently washed up in this habitat where it must be removed in order to restore the original landscape.

It is of interest to know the biodegradation behavior of plastics when exposed to conditions simulating this habitat, because this information can help in predicting the time needed for the biodegradation of the litter.

Biodegradation is determined by measuring the CO2 evolved by the plastic material when exposed to a sediment kept wet with salt-water in a reactor, to simulate the tidal zone.

Marine fresh-water habitats (for example, those found in brackish waters and estuaries) are not considered by this standard.

Reports shall clearly state the percentage of net CO2 generation for both the test and reference samples at the completion of the test. Furthermore, in the laboratory reports, the results shall not be extrapolated beyond the actual duration of the test.

NOTE 1—There is no known ISO equivalent to this standard.

Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.