Clingfilm/ Saranwrap, foodwrap and poisons

by Posted in 1.2 Plastic The Product Tagged , , 4 Comments

Not being much of a Suzy Home maker I have hardly ever in my life bought cling film. Rather glad now I’ve found out that PVC is added to most food wrap film  to make it more clingy. Though there are some films that do not contain it such as LDPE cling film.

PVC clingfilm contains Phthalates. These are added to make the plastic stretchy.

They have also been linked to possible birth defects and asthma and other nasty things.

And it gets better. PVC is known as the “poison plastic”. Toxic chemicals are used in its creation. One of those is vinyl chloride monomer (VCM). VCM is a gas and a known carcinogen causing cancerous tumors in the brain, lungs, liver and various tissues in humans.

Polyvinyl chloride (PVC) is  a chlorinated plastic 2011-22.7 changmai 2 (49)

Dioxins are unintentionally, but unavoidably produced during the manufacture of materials containing chlorine, this includes halogenated plastics, i.e made from chlorine or fluorine.

Burning these plastics can release dioxins.

Dioxin is a known human carcinogen and the most potent synthetic carcinogen ever tested in laboratory animals.

This means that that clingfilm is hard to recycle as it gives off nasty and dangerous fumes.

PVC cling film is not at the moment recycled – not that it cant be but that it is not as easy to recycle as LDPE clingfilm (film with out PVC)

According to some it is almost impossible to tell PVC clingfilm and polythene cling film apart.

PVC cling film is often used in the food industry.

China produces large amounts of PVC clingfilm.

Foodplast -( they make food wrap) – say sure leaching happens but the levels are completely safe.

How to cut the cling film

Am I teaching my granmother to suck eggs?

  • Keep it in a bowl with a plate on top.
  • Use a re-usable container with sealable lid.
  • Kilner jars (glass) are good and come in all sizes.
  • Get a sandwich box.
  • Don’t ever believe that wrapping your legs in plastic will burn any more calories than the energy it takes to wrap your legs in plastic.

fused plastic shopping tote

by Posted in 1.51 Reusing & Recycling Plastic Tagged , 7 Comments
Originally uploaded by eclipse_etc
 

 

plastic bags fused together using the heat of your iron can be used to make all kinds of new and exciting things.

For a great wriiten tutorial go here

http://etsylabs.blogspot.com/2007/05/long-overdue-fusing-plastic-bag.html

To see how to fuse and then make up a messanger bag, on you tube, go here

http://www.youtube.com/watch?v=sB1mE8e35UY

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Melt & Press Recycled Plastic

by Posted in 1.51 Reusing & Recycling Plastic Tagged , 4 Comments

One of the most innovative plastic recycling companies I have come across is the Wales based Smileplastics. They make the most wonderful plastic sheeting out of old wellies, C.D.ds, banknotes and everything else.

Here’s how

“The material we buy often looks like multi-coloured cornflakes which we lay out by hand in our moulds and then press in our hydraulic presses. Through heat and thousands of tons, the material fuses and takes the shape of the mould before we cool it and take out a solid sheet of recycled plastic – our product.

Most of our sheets are made from 100% waste plastic – we don’t add any binding agents or resins, so it is simply the combination of heat and pressure that transforms the individual chunks or flakes into a complete board.”

These are not just recycled plastics but works of art with the main ingredient determining how the end product looks. The children’s rubber welly sheet is large blobs of colour and rubbery. The banknote features shredded banknote in clear plastic for the rolling in millions feel

The plastic sheets can be used for anything from furniture to work surfaces.

More on recycling here

Other ways to recycle and reuse plastic trash here

Recycling and  waste plastic – a discussion

 

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plastic recycling process

by Posted in 1.51 Reusing & Recycling Plastic Tagged 3 Comments

Some years ago I went to visit a plastic recycling plant near my home. Since then there have been many innovations  but this is how your basic mechanical ( as oppose to chemical) plastic recycling plant works.

Those of you who read my blog  may think I am anti plastic recycling – not at all. Infact only the other day I was down at the plastic recycling plant, Home of Lynwood Plastics, in Halifax for a visit.

Here they recycle plastic into amongst other things
buckets
paint trays
grasscrete (mesh to grow reinforced grass in)
plastic lumber (plastic planks that can be used in place of wood)

The plastic for recycling is mixed according to type. The number found on some plastic products indicates what kind of plastic it is.

Up to 5% of the mix can be unknown plastic

The plastic for recycling goes into a big grinding machine where it is broken down into plastic grains.

The grains are melted and the resulting black plastic goo is poured into moulds or formed into products.

The goo smells quite plasticky but not unduly so. The machine is closed but not sealed – you can open the door and look at the goo glooping into the mould.

They can pretty much recycle any kind of plastic – from wrappers to traffic cones – as long as they know what kind of plastic it is.

The plastic needs to be fairly clean but not completely so – they can recycle empty paint cans with dried paint inside or plant pots with dust in.

They get their plastic for recycling from businesses. It is not domestic waste.

However they could recycle food wrappers and yogurt pots if they were cleaned before hand. They don’t want festering food waste on the premises for obvious reasons.

Plastic can be recycled pretty much indefinitely.

Polystyrene can be compressed and recycled

It takes a lot of plastic wrappers to make one plank.

Black plastic products with a kind of marbled finish are recycled.

You can find out more about plastic recycling here.

 

 

Nylon

by Posted in 1.3 Plastic Types - Fact Sheets Tagged

Nylon is often associated with the fabric of the same name but can be used to make all manner of things from fibre to  moulded objects.

Different nylon types are known by their numbers e.g. Nylon 6,6; Nylon 6,12; Nylon 4,6; Nylon 6; Nylon 12 etc

It is a polyamide plastic typified by amide groups (CONH)

Wallace Carothers at the Dupont Chemical company  discovered polyamides in 1931. On the 28th October 1938 commercial production of nylon 6,6 began.

Interestingly it was  first used to make the bristles on Dr West’s Miracle Tuft toothbrush.

But nylon is really synonymous with stockings.

On October 27, 1938, Charles Stine, vice president of Du Pont,announced that nylon had been invented. Unveiling the world’s first synthetic fiber not to a room full of corporates or scientists but to the three thousand strong women’s club members who were gathered at the site of the New York World’s Fair for the New York. He exclaimed ” nylon can be fashioned into filaments as strong as steel, as fine as a spider’s web, yet more elastic than any of the common natural fibers.” Thinking that “strong as steel” meant indestructible stockings, the women at the forum burst into applause.

Commercial production of nylon stockings began in 1939, and by the end of 1940 over 64 million pairs had been sold.

But the outbreak of World War 2 meant nylon had to be used for other more military things.

“The strength of nylon comes from amide groups in its molecular chain, which bond together very well. It also has a very regular shape, which makes it well suited to creating fabrics designed to stand up to intense forces.”  This made it ideal for the parachutes and ropes needed in war times. It is still  used now  for bulletproof vests and other hard-wearing items.

In 1941, nylon moulding powders began commercial production but nylon mouldings were not widely used until the 1950’s.

Today nylon fibres are used in textiles, fishing line and carpets. It is the second most used fiber in the United States.

Nylon films are used for food packaging. Because it can resist intense heat it is ideal for  boil-in-the-bag meals. Ugh!

Moulding and extrusion compounds find many applications as replacements for metal parts, for instance in car engine components. Intake manifolds in nylon are tough, corrosion resistant, lighter and cheaper than aluminium (once tooling costs are covered) and offer better air flow due to a smooth internal bore instead of a rough cast one. Its self-lubricating properties make it useful for gears and bearings.Electrical insulation, corrosion resistance and toughness make nylon a good choice for high load parts in electrical applications as insulators, switch housings and the ubiquitous cable ties. Another major application is for power tool housings.

Biodegradability

On the whole nylon, like most petroleum products, is not considered to be  biodegradable which means the accumulation of  an awful lot of trash.

For example an estimated £100 million worth (based on 2015 prices) or around 350,000 tonnes of used clothing goes to landfill in the UK every year . At least 60% f that will be synthetic fibres.

Degrading

But it seems ( according to Wikkipedia),  that Nylon 4 or polybutyrolactam can be degraded by the (ND-10 and ND-11) strands of Pseudomonas sp. found in sludge. This produces γ-aminobutyric acid (GABA) as a byproduct.[1]Nylon 4 is thermally unstable.[2]

Studies

The nylon4 portion in the blend films composed of nylon4 and nylon6 was degraded and completely disappeared within 4 months in two kinds of composted soils gathered from different university farms as well as pure nylon4 film reported previously, while the nylon6 portion remained even after the burial test for 15 months. Nylon4 powder was also degraded to carbon dioxide in the degradation test in an activated sludge obtained from a sewage disposal institution in Kogakuin University. Three species of microoganisms (i.e., ascomytous fungi) were isolated through the inoculation from the nylon4 film partially degraded in the soil on a medium containing nylon4 powder as a carbon source. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2307–2311, 2002

 

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Plastic eating microbes

by Posted in 2.1 reports, stats and studies Tagged 1 Comment

Is this a good idea?- much as I hate bad plastic I am rather attached to the computer and Dyson. Will they disappear before my very eyes. Here are some reports on plastic degrading microbes

Daniel Burd, a student at Waterloo Collegiate Institute, recently demonstrated that certain types of bacteria can break down plastic. During his scientific research, Daniel discovered that some types of bacteria in the soil can effectively degrade polyethylene plastic. He eventually isolated two microbial strains belonging to the genus Sphingomonas and Pseudomonas . Here’s a link to his research paper.

You can isolate your own plastic degrading microbes here http://www.instructables.com/id/How-to-isolate-plastic-degrading-bacteria-from-soi/?ALLSTEPS

According to Wikkipedia Nylon 4 or polybutyrolactam can be degraded by the (ND-10 and ND-11) strands of Pseudomonas sp. found in sludge. This produces γ-aminobutyric acid (GABA) as a byproduct.[1]Nylon 4 is thermally unstable.[2]

Studies

The nylon4 portion in the blend films composed of nylon4 and nylon6 was degraded and completely disappeared within 4 months in two kinds of composted soils gathered from different university farms as well as pure nylon4 film reported previously, while the nylon6 portion remained even after the burial test for 15 months. Nylon4 powder was also degraded to carbon dioxide in the degradation test in an activated sludge obtained from a sewage disposal institution in Kogakuin University. Three species of microoganisms (i.e., ascomytous fungi) were isolated through the inoculation from the nylon4 film partially degraded in the soil on a medium containing nylon4 powder as a carbon source. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2307–2311, 2002

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Dioxins

by Posted in 1.4 Additives Fact Sheets, More Information Tagged 1 Comment

The chemical name for dioxin is: 2,3,7,8- tetrachlorodibenzo para dioxin (TCDD).

The name “dioxins” is often used for the family of structurally and chemically related polychlorinated dibenzo para dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs).

Certain dioxin-like polychlorinated biphenyls (PCBs) with similar toxic properties are also included under the term “dioxins”.

Some 419 types of dioxin-related compounds have been identified but only about 30 of these are considered to have significant toxicity, with TCDD being the most toxic.

Dioxins are classed as a persistant organic pollutants, (POPs), also known as PBTs (Persistent, Bioaccumulative and Toxic) or TOMPs (Toxic Organic Micro Pollutants.)

POPs are a small set of toxic chemicals that remain intact in the environment for long periods and accumulate in the fatty tissues of animals. You can find out more about POPS here

burning plastic & cow

Dioxins occur as by-products in  the incineration of chlorine-containing substances such as PVC (polyvinyl chloride), in the chlorine bleaching of paper, and from natural sources such as volcanoes and forest fires, waste incineration, and backyard trash burning, and herbicide manufacturing. More on burning plastic here

The most toxic chemical in the class is 2,3,7,8-tetrachlorodibenzo-para-dioxin (TCDD). The highest environmental concentrations of dioxin are usually found in soil and sediment, with much lower levels found in air and water.

The word “dioxins” may also refer to other similarly acting chlorinated compounds (see Dioxins and dioxin-like compounds).

Dioxins are of concern because of their highly toxic potential. Experiments have shown they affect a number of organs and systems. Once dioxins have entered the body, they endure a long time because of their chemical stability and their ability to be absorbed by fat tissue, where they are then stored in the body. Their half-life in the body is estimated to be seven to eleven years.

In the environment, dioxins tend to accumulate in the food chain. The higher in the animal food chain one goes, the higher the concentration of dioxins.

“Humans are primarily exposed to dioxins by eating food contaminated by these chemicals. Dioxin accumulates in the fatty tissues, where they may persist for months or years. People who have been exposed to high levels of dioxin have developed chloracne, a skin disease marked by severe acne-like pimples. Studies have also shown that chemical workers who are exposed to high levels of dioxins have an increased risk of cancer. Other studies of highly exposed populations show that dioxins can cause reproductive and developmental problems, and an increased risk of heart disease and diabetes. More research is needed to determine the long-term effects of low-level dioxin exposures on cancer risk, immune function, and reproduction and development.”

Doixin is a known human carcinogen and the most potent synthetic carcinogen ever tested in laboratory animals. A characterization by the National Institute of Standards and Technology of cancer causing potential evaluated dioxin as over 10,000 times more potent than the next highest chemical (diethanol amine), half a million times more than arsenic and a million or more times greater than all others.” From the World Health Organisation

“Dioxins, which are highly toxic even at low doses, are produced when plastics are manufactured and incinerated. While dioxin levels in the U.S. environment have been declining for the last 30 years, they break down so slowly that some of the dioxins from past releases will still be in the environment many years hence.

In its 2000 final draft reassessment of the health effects of dioxins, the EPA concluded that dioxins have the potential to produce an array of adverse health effects in humans. The agency’s report estimated that the average American’s risk of contracting cancer from dioxin exposure may be as high as one in 1,000–1,000 times higher than the government’s current “acceptable” standard of one in a million.

Dioxins are also endocrine disruptors, substances that can interfere with the body’s natural hormone signals. Dioxin exposure, moreover, can damage the immune system and may affect reproduction and childhood development.” The green guide

Dioxins are unintentionally, but unavoidably produced during the manufacture of plastics containing chlorine, including PVC and other chlorinated plastic feedstocks.

Halogenated plastics include:
Chlorine based plastics:
Chlorinated polyethylene (CPE)
Chlorinated polyvinyl chloride (CPVC)
Chlorosulfonated polyethylene (CSPE)
Polychloroprene (CR or chloroprene rubber, marketed under the brand name of Neoprene)
PVC
Fluorine based plastics:
Fluorinated ethylene propylene (FEP)

Burning these plastics can release dioxins. 

More on PVC here

More on burning plastic here

Other Sources

U.S. Department of Health and Human Services

Wikkipedia

Antimony in the bottle, in the contents

by Posted in 1 ABOUT PLASTIC Tagged

Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2011 Jan;28(1):115-26. doi: 10.1080/19440049.2010.530296

Migration of antimony from PET bottles into beverages: determination of the activation energy of diffusion and migration modelling compared with literature data.

It was concluded that antimony levels in beverages due to migration from PET bottles manufactured according to the state of the art can never reach or exceed the European-specific migration limit of 40 microg kg(-1). Maximum migration levels caused by room-temperature storage even after 3 years will never be essentially higher than 2.5 microg kg(-1) and in any case will be below the European limit of 5 microg kg(-1) for drinking water. The results of this study confirm that the exposure of the consumer by antimony migration from PET bottles into beverages and even into edible oils reaches approximately 1% of the current tolerable daily intake (TDI) established by World Health Organisation (WHO). Having substantiated such low antimony levels in PET-bottled beverages, the often addressed question on oestrogenic effects caused by antimony from PET bottles appears to be groundless.

Water Res. 2008 Feb;42(3):551-6. Epub 2007 Aug 6.

Antimony leaching from polyethylene terephthalate (PET) plastic used for bottled drinking water.

Westerhoff P, Prapaipong P, Shock E, Hillaireau A.

Antimony is a regulated contaminant that poses both acute and chronic health effects in drinking water. Previous reports suggest that polyethylene terephthalate (PET) plastics used for water bottles in Europe and Canada leach antimony, but no studies on bottled water in the United States have previously been conducted. Nine commercially available bottled waters in the southwestern US (Arizona) were purchased and tested for antimony concentrations as well as for potential antimony release by the plastics that compose the bottles. The southwestern US was chosen for the study because of its high consumption of bottled water and elevated temperatures, which could increase antimony leaching from PET plastics. Antimony concentrations in the bottled waters ranged from 0.095 to 0.521 ppb, well below the US Environmental Protection Agency (USEPA) maximum contaminant level (MCL) of 6 ppb. The average concentration was 0.195+/-0.116 ppb at the beginning of the study and 0.226+/-0.160 ppb 3 months later, with no statistical differences; samples were stored at 22 degrees C. However, storage at higher temperatures had a significant effect on the time-dependent release of antimony. The rate of antimony (Sb) release could be fit by a power function model (Sb(t)=Sb 0 x[Time, h]k; k=8.7 x 10(-6)x[Temperature ( degrees C)](2.55); Sb 0 is the initial antimony concentration). For exposure temperatures of 60, 65, 70, 75, 80, and 85 degrees C, the exposure durations necessary to exceed the 6 ppb MCL are 176, 38, 12, 4.7, 2.3, and 1.3 days, respectively. Summertime temperatures inside of cars, garages, and enclosed storage areas can exceed 65 degrees C in Arizona, and thus could promote antimony leaching from PET bottled waters. Microwave digestion revealed that the PET plastic used by one brand contained 213+/-35 mgSb/kg plastic; leaching of all the antimony from this plastic into 0.5L of water in a bottle could result in an antimony concentration of 376 ppb. Clearly, only a small fraction of the antimony in PET plastic bottles is released into the water. Still, the use of alternative types of plastics that do not leach antimony should be considered, especially for climates where exposure to extreme conditions can promote antimony release from PET plastics.

Taken from the thegreenguide click here to visit

#1 PETE plastic water bottles have been shown to leach antimony into water. A recent study conducted by University of Heidelberg researcher Bill Shotyk, and published in the January 2006 Journal of Environmental Monitoring, found antimony levels in PETE water bottles were higher than levels found where the water was sourced. According to Shotyk, consumers should not be concerned about drinking water bottled in PETE plastic, as the levels found in water are below safe drinking standards. Nonetheless, it’s important to remember that leaving water in any plastic bottle for a prolonged period of time allows for chemical leaching to occur.

 

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Microplastic in the sea. Studies.

by Posted in 2.1 reports, stats and studies Tagged , , 1 Comment

From the BBC News

Dr Richard Thompson at the University of Plymouth researches what happens when plastic breaks down (degrades) in seawater

They have identified plastic particles of around 20 microns – thinner than the diameter of a human hair.
In 2004 their study reported the incidence of the particles had been increasing over the years.

They have found plastic particles smaller than grains of sand.

They estimate there are 300,000 items of plastic per sq km of sea surface, and 100,000 per sq km of seabed.

Thompson and his team conducted experiments on three species of filter feeders and found that the barnacle, the lugworm and the common amphipod or sand-hopper all  readily ingested plastic as they fed along the seabed.

They wanted to  establish if chemicals can leach out of degraded plastic and if plastic absorbs other contaminants such as PCBs and other polymer additives.

“The plastics industry’s response is that much of the research is speculative at this stage, and that there is very little evidence that this transfer of chemicals is taking place in the wild.It says it is doing its bit by replacing toxic materials used as stabilisers and flame retardants with less harmful substances.
Whatever the findings eventually show, there is little that can be done now to deal with the vast quantities of plastic already in our oceans. It will be there for decades to come.”

You can read more about the problems of micro plastic pollution here.

More Science

And if you want more data on the problem here are just a few of the hundreds of studies being done. Thanks to Fabiano of www.globalgarbage.org for keeping us well informed.

Jan Zalasiewicz, Colin N. Waters, Juliana Ivar do Sul, Patricia L. Corcoran, Anthony D. Barnosky, Alejandro Cearreta, Matt Edgeworth, Agnieszka Gałuszka, Catherine Jeandel, Reinhold Leinfelder, J.R. McNeill, Will Steffen, Colin Summerhayes, Michael Wagreich, Mark Williams, Alexander P. Wolfe, Yasmin Yonan, The geological cycle of plastics and their use as a stratigraphic indicator of the Anthropocene, Anthropocene, Available online 18 January 2016, ISSN 2213-3054, http://dx.doi.org/10.1016/j.ancene.2016.01.002.
(http://www.sciencedirect.com/science/article/pii/S2213305416300029)
Abstract: The rise of plastics since the mid-20th century, both as a material element of modern life and as a growing environmental pollutant, has been widely described. Their distribution in both the terrestrial and marine realms suggests that they are a key geological indicator of the Anthropocene, as a distinctive stratal component. Most immediately evident in terrestrial deposits, they are clearly becoming widespread in marine sedimentary deposits in both shallow- and deep-water settings. They are abundant and widespread as macroscopic fragments and virtually ubiquitous as microplastic particles; these are dispersed by both physical and biological processes, not least via the food chain and the ‘faecal express’ route from surface to sea floor. Plastics are already widely dispersed in sedimentary deposits, and their amount seems likely to grow several-fold over the next few decades. They will continue to be input into the sedimentary cycle over coming millennia as temporary stores – landfill sites – are eroded. Plastics already enable fine time resolution within Anthropocene deposits via the development of their different types and via the artefacts (‘technofossils’) they are moulded into, and many of these may have long-term preservation potential when buried in strata.
Keywords: Anthropocene; Plastics; Stratigraphy

http://www.globalgarbage.org.br/mailinglist/S2213305416300029_In_Press_Accepted_Manuscript.pdf

Carme Alomar, Fernando Estarellas, Salud Deudero, Microplastics in the Mediterranean sea: Deposition in coastal shallow sediments, spatial variation and preferential grain size, Marine Environmental Research, Available online 18 January 2016, ISSN 0141-1136,http://dx.doi.org/10.1016/j.marenvres.2016.01.005.
(http://www.sciencedirect.com/science/article/pii/S0141113616300058)
Abstract: Marine litter loads in sea compartments are an emergent issue due to their ecological and biological consequences. This study addresses microplastic quantification and morphological description to test spatial differences along an anthropogenic gradient of coastal shallow sediments and further on to evaluate the preferential deposition of microplastics in a given sediment grain fraction. Sediments from Marine Protected Areas (MPAs) contained the highest concentrations of microplastics (MPs): up to 0.90±0.10 MPs/g suggesting the transfer of microplastics from source areas to endpoint areas. In addition, a high proportion of microplastic filaments were found close to populated areas whereas fragment type microplastics were more common in MPAs. There was no clear trend between sediment grain size and microplastic deposition in sediments, although microplastics were always present in two grain size fractions: 2mm>x>1mm and 1mm>x 0.5mm.
Keywords: Marine litter; MPAs; Anthropogenic gradient; Sieve fractions; Contamination; Balearic islands

http://www.globalgarbage.org.br/mailinglist/S0141113616300058_In_Press_Accepted_Manuscript.pdf

Teresa Rocha-Santos, Armando C. Duarte, A critical overview of the analytical approaches to the occurrence, the fate and the behavior of microplastics in the environment, TrAC Trends in Analytical Chemistry, Available online 11 December 2014, ISSN 0165-9936,http://dx.doi.org/10.1016/j.trac.2014.10.011.
(http://www.sciencedirect.com/science/article/pii/S0165993614002556)
Abstract: Plastics can be found in food packaging, shopping bags, and household items, such as toothbrushes and pens, and facial cleansers. Due to the high disposability and low recovery of discharged materials, plastics materials have become debris accumulating in the environment. Microplastics have a dimension <5 mm and possess physico-chemical properties (e.g., size, density, color and chemical composition) that are key contributors to their bioavailability to organisms. This review addresses the analytical approaches to characterization and quantification of microplastics in the environment and discusses recent studies on their occurrence, fate, and behavior. This critical overview includes a general assessment of sampling and sample handling, and compares methods for morphological and physical classification, and methodologies for chemical characterization and quantification of the microplastics. Finally, this review addresses the advantages and the disadvantages of these techniques, and comments on future applications and potential research interest within this field.
Keywords: Debris; Detection; Environment; Marine environment; Microplastic; Plastic; Sampling; Seawater; Sediment; Water

Note to users: Accepted manuscripts are Articles in Press that have been peer reviewed and accepted for publication by the Editorial Board of this publication. They have not yet been copy edited and/or formatted in the publication house style, and may not yet have the full ScienceDirect functionality, e.g., supplementary files may still need to be added, links to references may not resolve yet etc. The text could still change before final publication.

Although accepted manuscripts do not have all bibliographic details available yet, they can already be cited using the year of online publication and the DOI, as follows: author(s), article title, Publication (year), DOI. Please consult the journal’s reference style for the exact appearance of these elements, abbreviation of journal names and use of punctuation.

When the final article is assigned to an volumes/issues of the Publication, the Article in Press version will be removed and the final version will appear in the associated published volumes/issues of the Publication. The date the article was first made available online will be carried over.

http://www.frontiersin.org/Journal/10.3389/fmars.2014.00070/full

Reisser J, Proietti M, Shaw J and Pattiaratchi C (2014) Ingestion of plastics at sea: does debris size really matter? Front. Mar. Sci. 1:70. doi: 10.3389/fmars.2014.00070

Keywords: microplastics, marine debris, plastic ingestion, zooplankton grazing, copepods

http://journal.frontiersin.org/Journal/10.3389/fmars.2014.00070/pdf

http://www.biogeosciences-discuss.net/11/16207/2014/bgd-11-16207-2014.html

Reisser, J., Slat, B., Noble, K., du Plessis, K., Epp, M., Proietti, M., de Sonneville, J., Becker, T., and Pattiaratchi, C.: The vertical distribution of buoyant plastics at sea, Biogeosciences Discuss., 11, 16207-16226, doi:10.5194/bgd-11-16207-2014, 2014.

Abstract. Millimeter-sized plastics are numerically abundant and widespread across the world’s ocean surface. These buoyant macroscopic particles can be mixed within the upper water column due to turbulent transport. Models indicate that the largest decrease in their concentration occurs within the first few meters of water, where subsurface observations are very scarce. By using a new type of multi-level trawl at 12 sites within the North Atlantic accumulation zone, we measured concentrations and physical properties of plastics from the air–seawater interface to a depth of 5 m, at 0.5 m intervals. Our results show that plastic concentrations drop exponentially with water depth, but decay rates decrease with increasing Beaufort scale. Furthermore, smaller pieces presented lower rise velocities and were more susceptible to vertical transport. This resulted in higher depth decays of plastic mass concentration (mg m−3) than numerical concentration (pieces m−3). Further multi-level sampling of plastics will improve our ability to predict at-sea plastic load, size distribution, drifting pattern, and impact on marine species and habitats.

Review Status
This discussion paper is under review for the journal Biogeosciences (BG).

http://www.biogeosciences-discuss.net/11/16207/2014/bgd-11-16207-2014.pdf

 

 

 

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Degradation Initiators & Degradable Plastic

by Posted in 1.2 Plastic The Product Tagged , 16 Comments

Traditional plastics do not biodegrade. Of course plastic breaks, tears and cracks. It weathers and sunlight makes it brittle, It falls apart – it degrades – but only into smaller pieces of plastic. And that can take hundreds of years. See Why Plastic Doesn’t Rot.

Plastic litter is not surprisingly increasing exponentially with disastrous environmental consequences.

But suppose there was a way of making non-biodegradable plastic, biodegradable? The plastic industry argue that they can do just that by means of chemical adatives known as degradation initiators.

Types Of Degradable Plastics

The ISO (International Organization for Standardization) has defined six types of degradable plastics.

  • Degradable – breaks down in some way.
  • Photodegradable, broken down by light
  • Oxidatively degradable broken down by oxygen.
  • Hydrolytically degradable. Broken down by water
  • *Biodegradable – can be broken down by microbes to mass, water and co2 but with no indication of how long that might take. May also need chemical addatives to make this process possible.
  • *Compostable – degrade at a rate that’s similar to other types of compostable materials, and they result, again, in water, carbon dioxide, humus, and inorganic compounds. Compostable plastics biodegrade naturally.They do not need additonal addatives to break down the polymers as they made from natural materials that microorganisms recognise.

This is a confusing list because the last two (*) seem to refer to the natural process of biodegrading while the others refer to  plastic with added degradation initiators. It is important to note that there is a huge difference. Degradable does not mean biodegradable despite what the plastics industry tries to imply.

What Are Degradation Initiators

Degradation initiators are added to the plastic mix in amounts of up to 2% of the total composition. Very basically, these addatives break the long unnatural plastic polymers into shorter recognisable polymers that microbes can attack and digest – or biodegrade.

English: illustration of the Oxo-Bio-Degradati...

English: illustration of the Oxo-Bio-Degradation is, as the name describes, a two-step process whereby the conventional polyolefin plastic is first oxo-degraded to short-chain oxygenated molecules (typically 2-4 months exposed) and then biodegraded by the micro-organisms (Bacteria, Fungi, etc.). (Photo credit: Wikipedia)

The process happens as follows.

  • Microbes are attracted to the additive;
  • They “crack” the long polymer allowing acces to other microbes and water.
  • Eventually these will break down huge polymers into smaller and smaller bits.
  • These smaller bits are then vulnerableto other microbes.

More Research

That’s the theory and it sounds good BUT as Green Plastics point out

“you can add an additive to normal, petroleum-based plastic that will make it become brittle and crumble in sunlight: this is referred to as making “photodegradable” plastic. Other additives can be put into plastic that will make plastic break down by oxidation: this is referred to as making “oxo-degradable plastic.”

These methods will make the bulk of the plastic appear to disappear; however, the small pieces (or even find “sand”) that is produced by this effect is still small pieces of plastic.  Nothing has changed. Over a matter of years, it is possible for the pieces to become small enough to be assimilated by microorganisms, but there is still a lot of research that needs to be done to verify how long this might take.  In the mean time, they are just very small pieces of plastic.”

Or this by Eco Savvy

“The only difference between “oxo-biodegradable” plastic and petroleum based plastic is the presence of an oxo-formulated additive in concentrations of 1-3% (metal salts) within the petroleum based plastic.  This additive allows the petroleum based plastics to degrade in the presence of oxygen, light, heat and moisture.

Oxo-biodegradable plastic is designed to degrade in the open environment and this short timeframe of biodegradation is not necessary. Furthermore, a high rate of conversion is not desirable because the conversion to greenhouse gases such as carbon dioxide contribute to the warming of the atmosphere, hole in the ozone layer and depletion of carbon available for the soil.”

The Right Place At The Right Time

The difficulty is of course ensuring that the plastic doesn’t start biodegrading in normal conditions so that the strength of the plastic product is not jeopodised. Biodegradation is designed to start in certain extreme conditions.

As 75% ofplastic ends up in landfill, most addatives are designed to work in landfill conditions.

While products may start to degrade outside of  the specified conditions but the process will take much longer.

The obvious flaw in this solution is the wrong product in the wrong place. For example plastic that has been manipulated to degrade quickly in a landfill conditions ending up as litter on the roadside where it will not degrade quickly.

Other Considerations

So, to become degradable, plastic has to be further chemically engineered. Obviously, this is by no means a natural process (as biodegrading is normally understood to be), rather it requires complex chemical eginerring.

The composition of these chemical addatives is secret and known only to the companies who produce them.

Biodegradable plastics are made using traditional (usually petrochemical based) plastics. They don’t always break down into harmless substances.

Confusing & Misleading Marketing

Because the initiators are bio-based this has led to the process being described as bio degradable. .

Which has led to confusion because now bio -degradable plastic could be a compostable plastic that biodegrades naturally OR plastic that has had a degradation initiator added to make it bio-degrade.

Compostable plastic is a plastic that can biodegrade with out chemical addatives within a certain amount of time.

The Guardian reported in October 2014 that

Last month, the FTC sent warning letters to 15 additional marketers, informing them that their claims “may be deceptive”. The FTC also requested “competent and reliable scientific evidence proving that their bags will biodegrade as advertised”. This time, the term of offense is “oxodegradable”, implying the bag will break down in time when exposed to oxygen.

And

“The plastic is not degrading, it’s fragmenting,” Greene said. Over time, as opposed to breaking down into less hazardous organic components, these plastic products break down into lots of small, equally toxic bits.

Why make plastics degradable?

Why go to the effort of making degradable plastic bags when we already have naturally compostable products such as paper bags and cornstarch bags. Why not use plastic for things we don’t want to rot away like drainpipes and use naturally biodegrading materials for disposable packaging?

Useful stuff to know

Degradable, biodegradable or compostable plastics – whats in a name
Why leaves rot and why most plastics don’t at Why Plastic Doesnt Rot

Degradable, biodegradable or compostable

So most plastics are made from oil and most plastics do not biodegrade. See how and why here… And yet you will find plastics described as degradable ...
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Compostable Plastics Index

Plastic was the name given to early synthetic products such as cellophane,  that were derived from cellulose. These plastics  were biodegradable. Then they learnt how to make ...
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Biodegrading and degradation – Plastic Lifespan,

So most plastics are made from oil and most plastics do not biodegrade. See how and why here... But what does that actually mean? Biodegrading Biodegradation ...
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Plastic eating microbes

Is this a good idea?- much as I hate bad plastic I am rather attached to the computer and Dyson. Will they disappear before my very eyes ...
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Degradation Initiators & Degradable Plastic

Traditional plastics do not biodegrade. Of course plastic breaks, tears and cracks. It weathers and sunlight makes it brittle, It falls apart – it degrades – but ...
Read More

Trash Vortex / 5 Gyres

by Posted in 2.1 reports, stats and studies Tagged , 2 Comments

Dotted around the world are  5 great trash vortexes. They are right out there in the middle of the sea and they are huge.  A “plastic soup” of waste floating in the Pacific Ocean is growing at an alarming rate and now covers an area twice the size of the continental United States, is how scientists have described one such.

This drifting “soup” stretches from about 500 nautical miles off the Californian coast, across the northern Pacific, past Hawaii and almost as far as Japan.

And it now appears that there are 4 more.

They are called trash Votrexes or the 5 gyres.

What happens is swirling currents collect up all the ocean debris and mix it into a big rubbish soup in the centre of the ocean. In the old days this rubbish was biodegradable so would rot.

Not any more.

These days its plastic which does not rot.

Result a vast expanse of debris – in effect the world’s largest rubbish dump – is held in place by swirling underwater currents.

Is how the Independant newspaper describes it.

Though Greenpeace have been worried for a while

Why are there no photos? Oysters garter has the best answer

Dont fancy reading? Watch one of these scary videos of what lurks beneath the waves

For educational dvds go to http://www.algalita.org/videos-research.html

other articles to read on the subject are Naked man in the tree