A vote of the Italian Parliament at the end of December 2010 rejected the attempt to once again postpone Article 1 of Law 296 (paragraphs 1129 and 1130) of 27 December 2006 from coming into effect, which provided the Italy-wide ban of non biodegradable single-use plastic shopping bags (hereafter referred to as "plastic bags").
Therefore, from 1 January 2011, the marketing of plastic bags in Italy is strictly forbidden: in the coming days shops and supermarkets will only be able to provide customers with the plastic bags remaining in their stockrooms, giving them to customers free of charge; and only until 31 August 2011 in supermarkets and 31 December in smaller shops.
From the information I have gathered on the web, I have noticed that in the U.S.A. no state has passed laws as strict as this, although ordinances of the prohibition of, or of fiscal penalisation for, plastic bags have been enforced in some cities. The municipal government of San Francisco, in 2007, issued an ordinance ban of plastic bags in supermarkets and pharmacies with annual sales of over two million dollars, and similar decrees have been promulgated in Los Angeles County, Portland, Oakland, Malibu, San Jose, Manhattan Beach, and Brownsville, among other locations.
My question is: Is the ban on the use of plastic bags a "political placebo", to quote Hank Campbell, i.e. a useless law passed by politicians as a demagogic pretence, or is it a positive measure which will insome way reduce environmental and sea pollution?
Plastic waste has invaded oceans
I have read that many U.S. ecological associations (the Algalite Marine Research Foundation, the Californian Ocean Protection Council, the Sierra Club, and so on), state that 60% - 80% of sea pollution is produced by plastic materials, of which 90% is floating pollution; they affirm that the Pacific Trash Vortex, also known as the Great Pacific Garbage Patch, is especially composed of plastic, with at least 700,000 km², and possibly more than 10 million km², containing a total amount (taking into consideration only plastic) of many millions of tons of plastic waste.
In “Demystifying”, the NOAA denies the existence of a "plastic island” in the Pacific, and therefore denies the possibility of defining the exact extent of waste, but states that the ocean currents produce a large spiral in the Pacific that gathers enormous amounts of waste into the “North Pacific Sub Tropical Convergence Zone", mostly composed of plastic waste, which produces myriads of microplastic particles as part of their degradation.
The National Oceanic and Atmospheric Administration (NOAA) of the U.S. Department of Commerce, in its thematic website on marine debris, has published a section entitled “De-mystifying the Great Pacific Garbage Patch",devoted to toning down excessive or indefinite news about this case.
Even the United Nations Environmental Programme (UNEP), in their article Action Urged to Avoid Deep Trouble in the Deep Seas of June 2006, states that “in the Central Pacific there are up to 6 pounds of marine litter to every pound of plankton”, and, referring to the surface ofthe sea, that "over 46,000 pieces of plastic litter are floating on every square mile of ocean today"
From the summary on page 49 about the types of waste collected between 2001 and 2006 on the coasts of the USA, I calculated that in a total of 238,103 items - between 70% and 80% - were plastic.
The main source of plastic waste in the sea is land activities
However the fact that plastic bags are one of the leading solid materials polluting the seas does not seem to have been proven, and I have not found any studies that indicate exact percentages of the amount that the various types of waste contribute to pollution.
Nevertheless, I think - at least among the solid floating waste that is gathering in the oceans - that those generated in land activities are more numerous than those produced by marine activities (fishing, goods and passenger transport, military navigation and yachting).
I have confirmation of this from the report "Marine Litter: A Global Challenge" of April 2009, from UNEP. On page 196, in the final review of data on debris collected in the period from 1989 to 2007 by the annual campaign to clean coasts worldwide, called the International Coastal Cleanup (ICC), where it is declared "the dominant sources of debris emanating from land-based sources and activities, globally."
Volunteers collecting waste on the beach
By the examination of the types of waste land-based sources, I am convinced that waste from plastic packaging is the most important component, due to both their number and their shorter lifecycle.
Packaging is the main source of plastic waste
It is a matter of huge numbers, and the percentage of plastic packaging that avoids collection and recycling systems is still high, which highlights the great contribution of these materials to global pollution: in Europe, 6,200,000 tons every year are neither recycled nor disposed of! Even in Italy, 850,000 tons each year are neither recycled nor disposed of!
The statistics published on the Plasticseurope website, the portal of the European association of plastics manufacturers of Brussels, Belgium, indicate a global consumption of plastic materials of 245 million tons in 2010 (including thermoplastics, polyurethanes, thermosettings, elastomers, adhesives, coatings, sealants and polypropylene fibres, PET polyethylene fibres, PA polyamides and polyacrylics), and specify that the highest percentage of these plastics is destined for packaging (37%), which would consequently reach a total annual consumption of more than 94,000,000 tons.
The above mentioned data seems compatible with the statistics processed by Eurostat, the European Environmental Agency, which calculates that for the 30 member countries of the European Community, 15,000,000 tons of plastic packing waste is produced for 502,737,000 inhabitants, and for Italy alone (in 2008), 2,200,000 tons was generated for 59,619,000 inhabitants.
It is sobering to see that in a continent which has a highly developed culture of environmental protection, more than 41% of plastic packaging waste is still dumped!
Plastic bags make up the largest amount of plastic waste
The U.S. International Trade Commission published its own investigation in May 2009 on imports of "Polyethylene Retail Carrier Bags" (hereafter referred to as "PRCBs"), which represents the most common typology of plastic bag; they certify that about 100 billion PRCBs are sold in the U.S. per year (102 billion in 2008).
In the category of plastic packaging waste, plastic bags are certainly an important component, if not in their weight, at least in their number.
Many Italian environmental associations (WWF, Legambiente, etc..) state on their websites that they estimate a national annual consumption of 20 - 25 billion plastic bags (called "shoppers" in Italy), against a total European figure of 100 billion, and a total world figure of between 500 and 1000 billion.
The figure of Italian consumption is consistent with the statements that I found from the Rubber and Plastics Federation, the association of Italian manufacturers, which indicate a production of about 260,000 tons of plastic bags in 2009, against 220,000 tons in 2006.
Dividing the volume of the total production in Italy by the unit weight of the bags, which, in most formats used, range from 8.5 grams to 15 grams, it obtained afigure of 17 - 30 billion units/year consumed in 2008, which is in line with the estimates above.
Plastic Bags are widely dispersed in the environment
It is easy to suppose that plastic bags are one of the main plastic packaging waste not recycled or disposed of, because:
- they are not industrial packing, which is managed through well-organised recycling systems;
- they are not bulky containers,in fact are very volatile, and are not easy to isolate;
- they are an individual tool, freely used and transported within the territory during daily mobility, leisure and holidays;
- they have avery low individual weight, and therefore a low caloric value and a low recovery value of raw material, and are therefore worth too little money to be of interest to companies that recycle plastic.
I have found confirmation of the low rate of the recycling of plastic bags in "Plastic waste in the environment - final report” by the General Environment Directorate of the European Commission of October 2010. On page 79 it publishes an estimate of the collection rates of the various types of plastic packaging, where you can see that the rate of collection of plastic bags is the lowest (5%), while industrial packaging reaches up to 100% of the collection of HDPE boxes, because "[...] They are mainly used in the industrial and commercial sectors, where the recoverypaths are better established."
“Plastic waste in the environment - Final Report” DG Environment - European Commission
I do not believe that 95% of all plastic bags are entirely dispersed in the environment, because many “not-collected” plastic bags are reused to pack up household waste, so they are disposed in the trash containers of municipal collection systems.
However, the Final Report of European Commission may reinforce the suspicion that many plastic bags are dispersed in the environment. These, thanks to their low weight and small size, are inevitably conveyed to the sea by rain, drains and rivers, and, having a very slow rate of degradation, are accumulating in increasing amounts.
I read that the Regional Director for the Southeast Pacific U.S. Environmental Protection Agency (EPA) has expressed his consent to the banning of plastic bags by the Governor of American Samoa, stating “[…] this action will decrease the amount of plastic waste in the territory and directly protect marine and birdlife in the Pacific.” And that this decision “[…] not only helps the local environment, it helps prevent plastic shopping bags from ending up in the Great Pacific Garbage Patch, an enormous area of floating plastic waste”.
Plastic Bags are very dangerous
1) they have a greater ability to suffocate sea creatures, which ingest them accidentally, especially larger fish and mammals, such as whales, that feed on plankton, as they "inhale" them with the water to filter plankton; and other fish and mammals such as turtles, which eat them mistaking them for jellyfish;
Moreover, compared to other plastic waste, plastic bags are more harmful to the marine environment because of two distinctive features:
2) as a result of their rapid rate of degradation into smaller and smaller pieces, they produce enormous amounts of micro particles, which are inevitably ingested by marine life on a massive scale, and may release toxic compounds that could enter the human foodchain.
In the Marine Pollution Bulletin n° 58 from 2009 (pages 1437 - 1446), I read the research conducted by Hideshige Takada of the Laboratory of Organic Geochemistry, Tokyo University of Agriculture&Technology, executed with patterned sampling of floating marine debris of polyethylene PE or polypropylene PP, collected from 14 places, from both beaches (near and far from built-up areas) and offshore, and analyses of these samples with a gas chromatograph.
The fragments and pellets of degraded PE and PP, during their extended period of floating on the sea, had absorbed polychlorinated biphenyls PCBs, Polycyclic aromatic hydrocarbons PAHs, Dichlorodiphenyldicholorethylene DDT, as well as Polybrominated diphenil ethersPBDEs, Octylphenol OP, Nonylphenol NP and Bisphenol BPA, in strengths from 1 nanogram per gram to 10 micrograms per gram, that were up to a million times higher compared to those taken from the sea.
Source: “Global distribution of organic micropollutants in marine plastics" by Hideshige Takada - Tokyo University
It is significant to note that PCBs, DDTs and PAHs are chemical compounds which are never used in the chemical industry as additives for polymers, therefore we have to consider they cannot come from the manufacturing process of the original materials of the fragments and the pellets of PE and PP; it is therefore inevitable to infer that those compounds were instead progressively absorbed by the fragments and the pellets of PE and PP during their long permanence in the sea.
The NOAA itself, on their website about marine debris mentioned above, affirms in their downloadable PDF document "garbage patch(es)" that "Debris found in these areas can easily be ingested by marine species, causing starvation and other impairments. Additionally, plastic debris act as “sponges,” absorbing organic contaminants such as PCBs (polychlorinated biphenyls). It is possible, though not proven, that plastics could also desorb these contaminants to marine life that ingest plastics."
It is true that the fragments and pellets of PE and PP analyzed by Takada’s team did not come from plastic bags, though it is also true that his research admits the possibility that even small fragments of plastic bags, mainly composed of the same PE material, are able to absorb large amounts of toxic compounds in the sea.
Embrittled plastic magnified by a microscope.
Plastic bags can be immediately replacedThere is another reason which has lead me to believe the ban of non-biodegradable plastic bags to be useful: despite the fact that they are not the only source of environmental and sea pollution, they are currently the only polluting plastic products which can be completely replaced with biodegradable materials, which are safe for the environment.
From a strictly technological point of view, the development of new natural polymers would today allow the replacement of synthetic polymers in many applications, as I also read in the paper "biopolymers in packaging", by Professor Francesco Pilati, of the University of Modena, Department of Materials and Environmental Engineering.
Biodegradable polymers are those polymers that undergo hydrolytic biodegradation catalyzed by bacteria - there are natural ones, such as polyhydroxyalkanoates PHAs, poly (lactic acid) PLA, cellulose, starch, etc., but there are also completely synthetic ones, such as polycaprolactone and some aliphatic polyesters.
For example, Professor Pilati states that polymers based on cornstarch or potato starch represent a family of biodegradable "biopolymers" derived from vegetable products that have mechanical and thermal properties which make them comparable with a wide range of traditional materials.
However, I think that the biopolymers currently in use still have a limited use, because the cost is still too high compared to synthetic polymers, at least for those applications where the incidence of the cost of the material is significant to the finished product: in a car, for example, a plastic dashboard is used in lower-cost models, and replacing it with a biopolymer would probably lead to a rise in the cost of the material, making the product un-saleable at current market prices.
Instead, for plastic bags, the polyethylene nowadays can be fully replaced by the new biodegradable biopolymers, because the unit price of single-use shopping bags is so low that even doubling it, to repay the higher cost of the production of biopolymers, the cost remains within an acceptable threshold for the market (in Italy the price has changed from EUR 0.04 - 0.06 for plastic bags to EUR 0.10 to 0.15 for bioplastic bags).
The alternative use of reusable fabric or synthetic fibre bags, which are not “throwaway”, is also available at a lower cost.
In corroboration of the effective possibility of a substitution, many brands of large retail trade in Europe have removed the availability of plastic bags a long time ago, replacing them with single-use shopping bags made with natural biodegradable polymers, which are used with full effect by millions of their customers
Plastic bags which are really biodegradable are certified
Hopefully the prohibition of non-biodegradable plastic bags should dictate the use of products made exclusively from natural polymers, with the exclusion of polymers also called "oxo degradable" or "UV degradable," which are synthetic polymers derived from fossil sources and made degradable with chemicals additives.
In fact, synthetic degradable polymers do not possess the European requirements of the technical standard EN13432, which, for biodegradability. means:
"The decomposition of organic chemicals by micro organisms with the presence of oxygen, in carbon dioxide, water and minerals of than any other element (mineralization) and new biomass or, in absence of oxygen, in carbon dioxide, methane, minerals and new biomass”.
Even in California have been issued two laws (AB 1972 and AB 2071) which forbid to label the plastics bags as "compostable" or "marine degradable" if they don’t respect the regulations ASTM D6400 (similar to EN 13432) and ASTM D7081.
As we have seen:
- plastic bags are the least-recycled plastic packaging waste (5% in Europe);
- every year about 500 billion plastic bags are produced worldwide;
- plastic bags are a waste which is highly dispersed in the environment;
- land activities are the main cause of sea pollution;
- plastic waste is the main component of waste floating in the sea (70 - 80%);
- plastic bags are dangerous, especially for marine life;
- particles derived from the decomposition of plastic waste can enter the food chain of living organisms;
- plastic waste fragments can absorb high concentrations of toxic substances in the sea;
- plastic bags are one of the most easily reproducible plastic materials today, by using biodegradable biopolymers;
- plastics bags have a low unit cost, so even great increases of the price of raw materials would cause a per capita expenditure of no higher than a few dollars per year.
So, as stated above, banning plastic bags is not the salvation of the environment, but can be a way to reduce the environmental impact of human activities.
Plastic wastes – Reduce, Reuse and Recycle of plastics are essential to make environment greener and safer:
1. Introduction – We find considerable growth in use of plastic everywhere due to various beneficial properties of plastics, such as:
(a) Extreme versatility and ability to be tailored to meet very specific technical needs.
(b) Lighter weight than competing materials, reducing fuel consumption during transportation.
(c) Extreme durability.
(d) Resistance to chemicals, water and impact.
(e) Better safety and hygiene properties for food packaging.
(f) Excellent thermal and electrical insulation properties.
(g) Relatively inexpensive to produce.
However, plastics waste creates lot of nuisances and degrade environment in a big way.
2. Pollution problems of plastics – Industrial practices in plastic manufacture can lead to polluting effluents and the use of toxic intermediates, the exposure to which can be hazardous. Better industrial practices have led to minimizing exposure of plant workers to harmful fumes.
There is growing concern about the excess use of plastics, particularly in packaging. This has been done, in part, to avoid the theft of small objects. The use of plastics can be reduced through a better choice of container sizes and through the distribution of liquid products in more concentrated form. A concern is the proper disposal of waste plastics. Litter results from careless disposal, and decomposition rates in landfills can be extremely long. Consumers should be persuaded or required to divert these for recycling or other environmentally acceptable procedures. Marine pollution arising from disposal of plastics from ships or flow from storm sewers must be avoided.
Recycling of plastics is desirable because it avoids their accumulation in landfills. While plastics constitute only about 8 percent by weight or 20 percent by volume of municipal solid waste, their low density and slowness to decompose makes them a visible pollutant of public concern. It is evident that the success of recycling is limited by the development of successful strategies for collection and separation. Recycling of scrap plastics by manufacturers has been highly successful and has proven economical, but recovering discarded plastics from consumers is more difficult.
3. Factors affecting recycling of plastics – Recycling and re-utilization of waste plastics have several advantages. Recycling and re-utilization of waste plastics lead to a reduction of the use of virgin materials and of the use of energy, thus also a reduction of carbon dioxide emissions. Economically, in some cases, plastics recycling may be profitable. However, a number of factors can complicate the practice of plastics recycling, such as the collection of the plastics waste, separation of different types of plastics, cleaning of the waste and possible pollution of the plastics. A further complicating factor is the low-value nature of most of the products that can be manufactured from recycled plastics. Reusing plastic is preferable to recycling as it uses less energy and fewer resources.
4. Advantages of reuse and recycle of plastics – It has been observed, to reduce bad effects of waste plastics, it is better to recycle andre-utilize waste plastics in environment-friendly manners. As per statistics, about 80% of post-consumer plastic waste is sent to landfill, 8% is incinerated and only 7% is recycled. In addition to reducing the amount of plastics waste requiring disposal, recycling and reuse of plastic can have several other advantages, such as:
(i) Conservation of non-renewable fossil fuels – Plastic production uses 8% of the world’s oil production, 4% as feedstock and 4% during manufacture.
(ii) Reduced consumption of energy.
(iii) Reduced amounts of solid waste going to landfill.
(iv) Reduced emissions of carbon-dioxide (CO2), nitrogen-oxides (NOx) and sulfur-dioxide (SO2).
5. Plastic bags and their nuisances– Plastic bags are popular with consumers and retailers as they are a functional, lightweight, strong, cheap, and hygienic way to transport food and other products. Most of these go to landfill and garbage heaps after they are used, and some are recycled. Once littered, plastic bags can find their way on to our streets, parks and into our waterways. Although plastic bags make up only a small percentage of all litter, the impact of these bags is nevertheless significant. Plastic bags create visual pollution problems and can have harmful effects on aquatic and terrestrial animals. Plastic bags are particularly noticeable components of the litter stream due to their size and can take a long time to fully break down. Many carrier bags end up as unsightly litter in trees, streets, parks and gardens which, besides being ugly, can kill birds, small mammals and other creatures. Bags that make it to the ocean may be eaten by sea turtles and marine mammals, who mistake them for jellyfish, with disastrous consequences. In developed countries billion bags are thrown away every year, most of which are used only once before disposal. The biggest problem with plastic bags is that they do not readily break down in the environment. It has been found that, the average plastic carrier bag is used for five minutes, but takes 500 years to decompose.
Plastic bags are made from ethylene, a gas that is produced as a by-product of oil, gas and coal production. Ethylene is made into polymers (chains of ethylene molecules) called polyethylene. This substance, also known as polyethylene or polythene, is made into pellets which are used by plastic manufacturers to produce a range of items, including plastic bags.
Plastics can be broadly split into two groups, those that consist of long strands (thermo softening) and those that also contain short cross-links (thermosetting). Thermo softening plastic will deform when heated and can be remolded into new shapes. Thermosetting plastics are much stronger, but once they have been formed into a shape, they will hold that shape indefinitely, and if heated they will merely burn.
Recycle and reuse of plastic bags can mitigate environmental problems.
6. Issues relating to plastics – There are about 50 different groups of plastics, with hundreds of different varieties. All types of plastic are recyclable. To make sorting and thus recycling easier, the American Society of Plastics Industry developed a standard marking code to help consumers identify and sort the main types of plastic. Before recycling, plastics are sorted according to their resin identification code.The type of plastics (as per the resin identification code) and their most common uses are given below:
a. Plastic process scrap recycling – Currently most plastic recycling in of the developed countries are of ‘process scrap’ from industry, i.e. polymers left over from the production of plastics. This is relatively simple and economical to recycle, as there is a regular and reliable source and the material is relatively uncontaminated. This is usually described as reprocessing rather than recycling.
b. Post-use plastic recycling – Post-use plastic can be described as plastic material arising from products that have undergone a first full service life prior to being recovered. Households are the biggest source of plastic waste, but recycling household plastics presents a number of challenges. One of these relates to collection.
c. Mechanical recycling – Mechanical recycling of plastics refers to processes which involve the melting, shredding or granulation of waste plastics. Plastics must be sorted prior to mechanical recycling. Mostly, sorting is done manually. Recently, technology is being introduced to sort plastics automatically, using various techniques such as X-ray fluorescence, infrared and near infrared spectroscopy, electrostatics and flotation. Following sorting, the plastic is either melted down directly and molded into a new shape, or melted down after being shredded into flakes and than processed into granules called re-granulate.
d. Chemical or feedstock recycling – Feedstock recycling describes a range of plastic recovery techniques to make plastics, which break down polymers into their constituent monomers, which in turn can be used again in refineries, or petrochemical and chemical production. A range of feedstock recycling technologies is currently being explored. These include: (i) Pyrolysis, (ii) Hydrogenation, (iii) Gasification and (iv) Thermal cracking.
Feedstock recycling has a greater flexibility over composition and is more tolerant to impurities than mechanical recycling, although it is capital intensive and requires very large quantities of used plastic for reprocessing to be economically viable.
7. Strategies for reduction of Environmental Impact of Plastics –
(a) Reduce the use– Source reduction Retailers and consumers can select products that use little or no packaging. Select packaging materials that are recycled into new packaging – such as glass and paper. If people refuse plastic as a packaging material, the industry will decrease production for that purpose, and the associated problems such as energy use, pollution, and adverse health effects will diminish.
(b) Reuse containers– Since refillable plastic containers can be reused for many times, container reuse can lead to a substantial reduction in the demand for disposable plastic and reduced use of materials and energy, with the consequent reduced environmental impacts. Container designers will take into account the fate of the container beyond the point of sale and consider the service the container provides.
(c) Require producers to take back resins – Get plastic manufacturers directly involved with plastic disposal and closing the material loop, which can stimulate them to consider the product’s life cycle from cradle to grave. Make reprocessing easier by limiting the number of container types and shapes, using only one type of resin in each container, making collapsible containers, eliminating pigments, using water-dispersible adhesives for labels, and phasing out associated metals such as aluminum seals. Container and resin makers can help develop the reprocessing infrastructure by taking back plastic from consumers.
(d) Legislatively require recycled content – Requiring that all containers be composed of a percentage of post-consumer material reduces the amount of virgin material consumed.
(e) Standardize labeling and inform the public – Standardized labels for “recycled,” “recyclable,” and “made of plastic type X” must be developed for easy identification.
8. Conclusion – Lots of innovations in recycling of waste plastics have been introduced in many countries. We have to see, we should not pollute environment while going for recycling and use of recycled products.