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					        Metro Manila produces about 8,000 tons of solid waste each day and is expected to reach
13,300 tons in 2014 (Baroña, 2004). According to a discards survey conducted by the EcoWaste Coalition
and Greenpeace Southeast Asia in 2006, synthetic plastics comprise the 76% of the floating trash in
Manila Bay, out of which 51% are plastic bags, 19% are sachets and junk food wrappers, 5% are
styrofoams and 1% of hard plastics. The rest were rubber 10% and biodegradable discards 13%
(EcoWaste Coalition, 2008).

        “Cutting back on the excessive use of plastic carry bags will lessen the demand for expensive oil
as well as minimize the waste and pollution resulting from the production, consumption and disposal of
plastic bags,” said Gigie Cruz of the EcoWaste Coalition’s Task Force on Plastics, adding that “our
voracious consumption of plastic bags is increasing our dependence on imported oil and polluting the
environment.”

        The “plasticization” of our lifestyle, observed the EcoWaste Coalition, ties into the swelling
demand for oil as plastic bags and other plastic stuff are made of crude oil, natural gas or other
petrochemical byproducts. For plastic bags alone, it is estimated that some 430,000
gallons of oil are needed to produce 100 million pieces of these omnipresent consumer items on the
planet.

      Along with less visible but equally harmful pollutants, plastics have smothered the bay’s
mangrove, sea grass, and coral ecosystems, and as in other coastal areas where plastic trash
predominates, have led to the death of birds and marine animals via ingestion or entanglement. March9

        Information obtained from the Worldwatch Institute, an independent research organization,
indicates that plastic factories around the globe mass-produce 4-5 trillion bags yearly and that
consumers throw about 500 billion bags annually. Plastic bags can last for over 1,000 years.

         According to another study4 by the World Bank, a Filipino generates around 0.3 to 0.7 kilograms
of garbage daily depending on income levels. The National Capital Region produces the highest amount
of waste accounting to 23% of the country's production, that is a quarter of the country's generation
waste as a whole. Accordingly, a study on the waste generation rate (grams/person/ day) by the Japan
International Cooperation Agency (JICA) in 1998 estimated that the total waste generation in Metro
Manila has been estimated at 5,350 tons per day in 1997 and was projected to increase to 6,235 in
2005, approximately 2% increase per annum. However, a recent survey by the Metro Manila
Development Authority (MMDA) in December 2000 estimates that the generation rate in Metro Manila
has grown to 4.5% annually in the last four years. Metro Manila's solid waste is highly organic and
recyclable. Forty-nine percent of this is biodegradable and includes large amounts of kitchen waste and
to a lesser extent, garden waste. This high percentage of biodegradable waste indicates that it could be
used as compost. There is also a great potential for recycling, as 42% of the waste is made of recyclable
items such as paper, plastic and metal.
4 World Bank. The Philippines Environment Monitor 2001. (Pasig City: Philippines: World Bank,
December 2001).


Environmental Issues In The Philippines. www.asria.org [retrieved 2008, June 13]
EcoWaste Coalition. June 8, 2008.



FEMS Microbiol Rev, 1992 Dec, 9(2-4), 311 - 6
Microbial degradation of natural and of new synthetic polymers; Schink B et
al.; In landfills, deposited waste material is usually faced with strictly anoxic
conditions . This means that the design of new biodegradable polymers must
take into consideration that degradation should be possible especially in
the absence of molecular oxygen . Poly-beta-hydroxybutyrate is depolymerized
by the anaerobic fermenting bacterium Ilyobacter delafieldii through an
extracellular hydrolase. Monomers are degraded inside the cells through classical
beta-oxidation . Polyalkanoates containing odd-numbered or branched-chain acid
monomers should he degraded in an analogous manner; in most cases the final
mineralization of these residues requires special pathways . A comparison of the
chemistry of natural polymer biodegradation leads to the conclusion that
synthetic biodegradable polymers should be designed in the future to
contain linkages which can be cleaved by extracellular hydrolytic enzymes
. Recent findings on aerobic and anaerobic bacterial degradation of synthetic
polyethers suggest that natural evolution of new depolymerizing enzymes, perhaps
from existing hydrolases, could be possible in a reasonable amount of time,
provided that the monomers are likely energy sources for a broad variety of
microbe

				
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