Adaptation Measures: Beach Cleans

Hello all!

As mentioned, I will speak briefly about beach cleans this week. I recall myself going to mass beach cleaning activities in secondary school, having been instructed to pick up beach litter like bottles, plastic bags, food wrappers and drink cans before they were swept into the sea. However, it has struck me that large single-use garbage bags were used to store the beach litter as seen in Figure 14. 

Figure 14. Doing my part for the environment when I was 14 by cleaning up the shorelines of Singapore. Source: Author.

It personally brings to mind whether we will ever be able to completely eradicate plastic bag use, after developing such a form of dependence on it. I am personally still not able to avoid the use of single-use plastic bags for waste disposal at home, as they remain the cleanest and most efficient way to collect food waste and cooked liquids. How do we reuse and recycle these garbage bags? How do we make sure our mode of disposal ensures that they do not end up in water bodies?

In my next post after Christmas, I would conclude this blog. Have a great Christmas (and happy birthday to myself!)

Adaptation Measures: Legal Frameworks

Hello all!

In this post, I would be talking about how we may reduce negative externalities from plastic bags. Although there have been many abovementioned suggested measures, some technological measures have been well-discussed by a colleague (eg. Seabins, The Ocean Cleanup), and I would therefore choose to focus on the common measures - legal frameworks and beach cleanups.

Legal Frameworks

One agreement that has been particularly relevant for the control of plastic pollution is the London Convention 1972, later ratified as the London Protocol 1996. The former Convention aimed to control marine pollution by establishing a black-grey list approach to wastes, where items on the black list were prohibited from dumping and items on the grey list required a special permit before dumping could be carried out. The Protocol tightened the prevention of pollution even further by adopting a "reverse list", implying that all dumping is prohibited except otherwise indicated on the reverse list with a special permit. Incineration and export of waste products at sea were also disallowed. Both these frameworks indicate the prevention of dumping of plastics, and the ratification of the Protocol among states represent their move towards environmental consciousness. Extracted examples of these lists are seen in Table 4.

Table 4: Black-grey list of London Convention 1972, and reverse list of London Protocol 1996.

Legal Frameworks	Item lists
London Convention 1972	Black list - Organohalogen compounds - Mercury and mercury compunds - Cadmium and cadmium compounds - Persistent plastics and other persistent synthetic materials* - Crude oil Grey list - Wastes containing matter such as arsenic, chromium, copper, lead (more in Annex II). - Containers, scrap metal and bulky wastes
London Protocol 1996	Reverse list - Sewage sludge - Fish waste, or material from fish processing operations - Vessels and platforms or other man-made structures at sea - Dredged material - Organic matter of natural origin - Inert, inorganic geological material - Carbon dioxide from capture processes for sequestration

There is great difficulty in obtaining dumping permits - (a) waste management audit to minimise the amount of waste to be dumped, (b) review all other modes of disposal including reuse and recycle before disposal, and (c) to consider for disposal on land before sea disposal, and these mean that sea dumping would be minimised. To ensure that parties comply with the protocol, it is essential for all parties to submit regular reports on dumping activities; unfortunately, the overwhelming efforts required mean that countries often opt out in favour of their continued convenience. Enforcement is also tough as curbing illegal dumping remains a challenge from the vast expanse of the unmonitored ocean waters.

On the bright side, I read a related article on a suggested local action plan for Singapore (where I come from) to reduce its marine trash and remedy its ugly shorelines following these global frameworks, arguably a nationalistic measure which may be more useful to encourage compliance within a country's own territorial waters.

In my next post, I will then talk briefly about beach cleanups. See you!

Mitigation Measures: Alternative Materials?

Hello all!

Two posts ago, I mentioned that a particular case study brought up "encouraging alternative bags" as a solution to forge greater environmental identity. In this post, I will discuss the problems of using alternative packaging materials based on research by the UK Environment Agency, which arguably displays an objectivity to adopt the best approach for the environment. Due to differing standards on the reference of LDPE and HDPE bags with the UNEP classifications, I will drop the abbreviations to avoid confusion and discuss them in terms of thickness, comparing between disposable thin bags and reusable thick bags.

Environmental Impacts of Different Carrier Bags (Source: UK Environmental Agency)

The study documented the environmental impact across its production, use and disposal. The bags considered were: a) conventional thin plastic bags, b) thicker plastic "Bags For Life", c) paper bags, d) non-woven polypropylene bags and e) cotton bags. There were five assumptions put in place in this study to derive the specific figures seen in Table 3:

1. Volume and weight of carrier bags were averaged across UK supermarkets.

2. Energy consumption was estimated by grid electricity.

3. Production waste from (a), (b) and (d) were taken to be recycled, waste from (e) was taken to be landfilled.

4. Transport distances were determined by industry experts, and were summed for the transportation of raw materials and the delivery of the finished bag to the site of retail.

5. IPCC 2007 characterisation factors determined the carbon footprint of each bag through its life cycle - summing resource use, production, transportation and end-of-life processes. A more detailed impact assessment using the CML2 Baseline method was used to calculate nine specific categorical environmental impacts, such as acidification and eutrophication.

Table 3: Characteristics and environmental burdens of each carrier bag, summarised and rounded off to 1 decimal place (Source: UK Environmental Agency).

Type of bag	Mass per bag (g)	Items per bag	Energy consumed per 1k bags (kWh)	Waste generation per 1k bags (g)	Typical total transport scenarios to UK	Carbon footprint per bag (kg CO2 eq)	End-of-life processes possible
Thin plastic bags	8.1	5.9	6.2	418.4	Lorry: 600km Sea: 16000km Rail: 270km	1.6	- Landfill - Incinerate - Mechanical recycling
Thick plastic bags	34.9	8	6.4	171.2	Lorry: 700km Sea: 21000km Rail: 560km	6.9	- Landfill - Incinerate - Mechanical recycling
Paper bags	55.2	7.4	-	-	Lorry: 1200km	5.5	- Landfill - Incinerate - Mechanical recycling - Compost
Non-woven PP bags	115.8	7.3	-	5850	Lorry: 600km Sea: 15000km Rail: 280km	21.5	- Landfill - Incinerate - Mechanical recycling
Cotton Bags	183.1	10.6	11	1800	Lorry: 680km Sea: 15000km	271.5	- Landfill - Incinerate

As seen in Table 3, the thin plastic bags have shown to demonstrate the lowest carbon footprint and the lowest environmental impacts in 8 out of 9 categories not displayed here; cotton bags, on the other hand, showed shockingly large environmental burdens. In  the consideration of every step of this life cycle in the production of one bag, it creates a carbon footprint much greater than the other carrier bags: (a) Process of growing cotton requires large land areas, year-round irrigation, and application of fertilisers and pesticides for soil cultivation, leading to large abiotic resource depletion, (b) Transportation to cotton mills with other required raw materials drove vehicle pollution, as well as the final transportation to consumers, and (c) Conversion of cotton into cotton yarn consumes large amounts of energy and water.

Assuming that 40.3% of thin plastic bags were reused as bin liners (a figure averaged across all respondents), reusable thick plastic bags, paper bags, PP bags and cotton bags had to be reused 5, 4, 14 and 173 times respectively to bring their carbon footprints below that of thin plastic bags.  These figures unfortunately greatly challenge the flow of this blog thus far by showing that alternative packaging materials may help plastic pollution, but probably not the Earth overall - arguably, there may be issues more pressing than the current concerns about aquatic biodiversity, showing greater complexity of the issues around plastic pollution. It is obvious that bags intended to last longer should use a greater amount of resources and therefore in its production cause greater environmental impacts - however, is this (exceedingly large) amplification of environmental impact justifiable?

I hereby adopt the view that our actions should be in taken for the best interests of our Earth, rather than the sole issue of plastic pollution. My purpose is not to drive pessimism, neither is it to continue encouraging single-use thin plastic bags, but to highlight that the key to reducing the overall environmental impact from packaging is to reduce our uses of plastic bags, and to reuse them for secondary applications as much as possible. Reduce, reuse, recycle. In my next post, I will be talking about the other branch of legislations: adaptation measures when plastics have already found their way into the Earth system.

See you!