Tag Archives: bacteria using PET as food source

PLASTIC and POLLUTION

25 Apr

News about pollution with plastic is everywhere. It has definitely hit public consciousness. Governments, businesses, and individuals are now conscious of the amount of unnecessary plastic waste thrown out daily and the damage this causes  (although I remain appalled at the number of plastic bottles that are still thrown from car windows onto my garden).

Plastic pollution means plastic products that are disposed of in a way that they cause damage to wildlife, wildlife habitat, or humans.

Plastics are categorized into micro-, meso-, or macro debris. Virtually everyone nowadays must be aware of macro debris; more than 8 million tons of plastics are dumped into the seas yearly resulting in animals being strangled by plastic loops, thousands of albatross chicks killed by the pieces of the plastic they mistake for food, the appalling aesthetics (and health hazards), of hitherto pristine beaches littered with plastic.

Microplastics are small plastic particles of less than 5 mm diameter. They are classified as primary; for example (from clothing and industry) and secondary, from the breakdown of larger macro plastic debris (for example debris at the bottom of the oceans). Microplastics are used, to a degree that I was unaware of, in the cosmetic industry: for example in exfoliates, soaps and other personal care products such as body scrubs and toothpaste. These plastics enter the sewage systems and, as they are too small to be completely retained by the preliminary treatment screens of wastewater plants, they leach into rivers and oceans. They do not degrade easily, persisting for years and so accumulating in the bodies and tissues of animals and plants and hence the food chain.

These microplastics are made of polyethylene, (a component of plastic), polypropylene, polyethylene terephthalate, or nylon.

Plastics seem to be ubiquitous; items of clothing can contain polyester, nylon and acrylic synthetic fibers that shed and persist in the environment. It is a said that a load of laundry can contain more than 1,900 fibers of microplastics, (with fleeces releasing the highest percentage of fibers).

Spillage, coming from packing materials during transport and from processing plants are two other important sources of pollution, sometimes in the form of macroplastics, otherwise as secondary microplastics resulting from long-term degradation. A Swedish investigation, using an 80 µm mesh in Swedish waters, showed that the typical microplastic concentrations of 150–2,400 microplastics per m .   increased to 102,000 per m. in a harbor adjacent to a plastic production facility. A Californian study found that after a storm, the transport of plastics increased from 10 to 60 microplastics per m.

Recreational and commercial fishingmarine vessels, and marine industries are all sources of plastic that can directly pollute the sea. I was surprised that fishing equipment, such as lines and netting (which drift to variable depths in oceans) are a particular hazard. That awful beach debris comes either from people who just dump their debris, or from beaching of materials carried by ocean currents.

This is an urgent geopolitical problem which slowly and none too soon, is being faced up to:

A fascinating development has been the discovery of species of bacteria that uses polyethylene terephthalate (PET), one of the most common forms of plastic, as a food source. This is a huge find: PET takes 450 years to completely degrade in the environment. These bacteria, it is said, can digest it in weeks. But on what scale and how will these bacteria be contained? Will birds eat the bacteria?

Other solutions under consideration are:

a) In the UK a ban has been launched on microbeads. Other countries are introducing this ban.

b) Plastic-Free Aisles in Supermarkets, an Amsterdam store has a plastic free aisle containing more than 700 items. This cannot come soon enough. The amount of plastic packaging, of fruit/veg for example, in my local supermarket is ridiculous and dirtying your hands by handling potatoes, vegetables etc.(as some people object to), can help to build up natural immunity.

c) Banning Cotton buds and Plastic Straws
It is planned that this should be done within a year

d) Plastic Bottles

Have been described as ‘almost a flagship for the wider issues of marine plastic pollution’. 7.5 billion of much larger number of bottles end up in landfill in the UK, others get into the sea. In Britain there has been a 10% rise in plastic pollution on the beaches in the past year. There is now a huge campaign to reduce/stop the production of plastic bottles. Reusable containers are becoming popular. A 25p charge on disposable coffee cups is under consideration — this would greatly reduce the 5 billion cups dumped every year. Also discounts are being offered to consumers who bring their own reusable cups, for example Pret A Manger gives this discount. Since a 5p plastic bag tax was first introduced in the UK in October 2015, there has been a 90% fall in bag use — with 9 billion fewer bags being used across the country, according to figures released last July Tesco took the ban one step further, banning the 5p single-use carrier bags completely, in favour of a 10p bag for life. In his November budget, U.K Chancellor Philip Hammond announced plans for a tax increase on disposable plastic items, including takeaway boxes. These plans are being consulted on.

e) Water fountains. I like this idea. It takes us back decades! The suggestion is that if fresh water is available to the public, we will buy less bottled water.  Greater access to water fountains across the UK is being investigated

f) Recycled Plastics.

Currently, firms in the UK pay one of the lowest contributions to recycling their waste in the whole of Europe — with taxpayers instead paying 90% of the recycling costs.

The government could introduce incentives for industries designing packaging that is easier to recycle, and raise charges on packaging that is difficult to recycle, making packaging producers more responsible for the type of products they are putting on the market.

g) School education, even a half hour presentation, fitted into the crowded school curriculum, would make an impression

A summary of the UK’s approach was given by the Environment Secretary 1)Cut the total amount of plastic in circulation. 2) Reduce the number of different plastics in use, because that will help recycling firms. 3) Improve the rate of recycling, which has been slipping recently. 4) Make it easier for individuals to know what goes into the recycling bin and what goes into general rubbish.

To this, information could be added as to how our general rubbish is distributed (i.e. the % that is exported (untreated), the % the goes into landfill the % that is burnt.

This is a serious geopolitical problem; if these approaches are adopted widely the situation could be contained and gradually reduced.

Advertisements