Green Products: Old Study Proves PLA Creates Methane in Landfills

Portland, OR -- (SBWIRE) -- 09/18/2012 -- The standard for determining anaerobic biodegradable plastic materials is the ASTM D5511-12 testing method. The Japanese BioPlastic council funded testing to see the total anaerobic(Landfill) biodegradation of PLA. What they found directly contradicts recent “peer-reviewed” studies funded by PLA manufacturers and testing facility OWS.

While PLA manufacturers have stated that at 35C very little methane had occurred, it directly contradicts Japanese studies at the same temperature, the esteemed Japanese BioPlastic Council funded testing that reported 2.9% methane gas production a week at 35C, while PLA manufacturers have stated that their test reports represent 100 years, it is obvious their “peer-reviewed” report is not truly peer-reviewed.

According to Crawford and Smith 1985; DOE 1995; EPA 1993, Landfills see temperatures between 77° F and 113° F, although temperatures up to 158° F have been noted. PLA manufacturers and ASTM D.20 have continued to reject these studies and have veered towards their own methods of testing biodegradation in landfill environments. Current legislation in the State of California have indicated a lack of knowledge or a constant battle of territory for PLA against Oxo-degradable additives and biodegradable plastic additives. While many studies and reports have been conducted on PLA in regards to which compost facilities will actually compost the material in various ranges of time from 3 weeks to 18 weeks, many compost facilities and the USDA have rejected PLA plastics in compost. US Compost Council has recently written a statement concerning the ASTM testing standard ASTM D6400-12 that the test does not represent real world environments and is only meant for laboratory environments.

During this time the majority of PLA does enter the landfill environment and will create methane gas, these tests have been funded by such esteemed organizations as the Japanese BioPlastic Council. Their test concluded that:

PLA showed a slight biodegradability under aquatic conditions at the mesophilic temperature. PLA was not degraded when using the ISO 14853 method. PLA was not degraded at all after 100 days using the ASTM D5210 method. In our experiment, the PLA degradation was slow at 35 °C. Biogas evolution from the PLA vessels at 35 °C were observed in 55 days and the biodegradation rate was 2.9%/week. The anaerobic fermentation tank operating at 35 °C is thought to be unsuitable for the PLA degradation. For the high-solid test at the thermophilic temperature, PLA was degraded to 60% after 40 days at 52 °C using the ASTM D5511 method . In our experiment, PLA degraded about 60% in 30 days, about 80% in 40 days, and about 90% in 60 days using the new evaluation system. PLA is thought to be degraded in the anaerobic fermentation tank at the thermophilic temperature under slurry conditions.

That is why BioSphere biodegradable plastic has designed their plastic additive which work for the manufacturer and consumer, easily understandable and without the confusion. Products using BioSphere biodegradable plastic additive get thrown into a landfill, biodegrade, create methane, methane is then captured by 594 landfills in the U.S.A. and powers homes and businesses across the country.

BioSphere plastic sells competing technology to PLA that is disposed into landfill environments.

The full report funded by the Japanese BioPlastic Council can be found at the US National Library of Medicine. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2769157/