Environmental Engineering Reference
In-Depth Information
Figure 4.15
A comparison of fossil resources and carbon footprint of
conventional plastics with PLA and PHA.
Source: Reproduced with permission from Nova Institute GmbH, Huerth/
Germany (2012). Downloaded from
http://www.bio-based.eu/ecology/
However, the externalities associated with bio-based plastic production
(that includes intensive agriculture to produce the biomass) can exceed
those for conventional plastics. Pesticide/fertilizer pollution from
agriculture is already widespread and can affect human populations. For
instance, Hottle et al. (2013) report the acidification potential, ecotoxicity,
eutrophication, ozone depletion, and PM 2.5 particulates to be significantly
higher for PLA compared to conventional PE and PET. The overall potential
for human health impacts is also lower for PLA compared to PET (but still
higher than for PE or PP). Similar results have been reported for PHA.
With bio-derived polymers that are biodegradable (such as PHA and PLA),
an additional consideration is the potential negative impact these have on
material recycling.
