Tag Archives: plastics

The Plastic in the Oceans

Marine debris on Hawaiian coast. Image from wikipedia

The steady build-up of garbage in the world’s oceans is a “tremendous challenge” and a growing threat to the planet’s marine ecosystems with the potential for “significant socio-economic consequences,” the United Nations Environment Programme (UNEP) heard today.  In the final day of the 16th Global Meeting of the Regional Seas Conventions and Action Plans, held in Athens, Greece, scientists, policymakers and delegates gathered amid growing global concern over the accumulation of plastic waste in oceans and seas – a problem that could pose an estimated $13 billion in damage to marine life and habitats, and which demands a comprehensive remedy.

Addressing the meeting, Jacqueline Alder, Coordinator of UNEP’s Freshwater and Marine Ecosystem Branch, applauded the creation of a “visioning roadmap” seeking to chart a way forward for oceans governance in the coming decade, particularly in the areas of extraction, governance, impacts of a changing climate, ocean acidification, and pollution.

The meeting generated broad agreement among experts and policymakers regarding the issue of microplastics – tiny pieces of plastic less than one millimetre in size – which, they said, deserved more attention in order to better grasp their physical and biological impact on the marine ecosystems they pollute.  In addition, they advised a three-tier approach tackling marine litter at the national, regional and municipal levels as municipalities tends to have responsibility for solid-waste management….

The five garbage patches, or gyres, that have amassed in the world’s oceans as plastic waste and other jettisoned materials are carried by the currents. The patches themselves now occupy a total of 15, 915, 933 square kilometres of ocean, threatening the marine environment and the plants and animals living within it.

UN meeting hears call for greater marine protections as plastic waste accrues in oceans, UN Press. Release, Oct. 1, 2014

Marine Pollution: the benefits of plastic in the sea

Beach at Msasani Bay,  Dar es Salaam, Tanzania. image from wikipedia

The malign effect of floating plastic debris on seabirds, turtles and other sea creatures is well known. But, as Dr Mincer and Dr Amaral-Zettler have discovered, plastic debris also provides a new habitat for organisms small enough to take advantage of it.  The two researchers collected pieces of plastic from various sites in the North Atlantic. They then examined each using DNA analysis, and also an electron microscope, to see what was living on it. Lots of things were. Altogether, they discovered about 50 species of single-celled plant, animal and bacterial life. Each bit of debris was, in effect, a tiny ecosystem.…Plastics are energy-rich substances, which is why many of them burn so readily. Any organism that could unlock and use that energy would do well….Less encouragingly, Dr Mincer and Dr Amaral-Zettler also found cholera-like bacteria in their tiny floating ecosystems. Both fish and seabirds act as vectors for cholera (the former bring it into human settlements when caught by fishermen, the latter when resting ashore or nesting), so anywhere that such creatures might pick up cholera bugs is something worth keeping an eye on.

The researchers paint an intriguing picture of the adaptability of nature, and provide another piece of the jigsaw that is the Anthropocene. Conservationists intent on preserving charismatic megafauna have reason to lament the spread of plastics through the ocean. But those interested in smaller critters have been given a whole, new sphere—the plastisphere—to study.

Marine ecology: Welcome to the plastisphere, Economist, July 20, 2013, at 7

Choking the Oceans

Massive amounts of phosphorus, a valuable fertilizer needed to feed a growing global population, are being lost to the oceans as result of inefficiencies in farming and a failure to recycle wastewater.. Phosphorus pollution, along with other uncontrolled discharges, such as nitrogen and sewage, are linked with a rise in algal blooms which in turn harm water quality, poison fish stocks and undermine coastal tourism.  In the United States alone, the costs are estimated to be running at over US$2 billion a year, indicating that globally and annually the damage may run into the tens of billion of dollars.

At the same time there is also growing concern over the impact of billions of pieces of plastic, both large and small, on the health of the global marine environment.  New research suggests that the plastic broken down in the oceans into small fragments —alongside pellets discharged by industry—may absorb a range of toxic chemicals linked to cancer and impacts the reproductive processes of humans and wildlife.

Experts say both phosphorus discharges and new concerns over plastics underline the need for better management of the world’s wastes and improved patterns of consumption and production.  The two issues are spotlighted as among key issues —deemed persistent, re-emerging or newly emerging— in the United Nations Environment Programme’s (UNEP) Year Book 2011 which is being presented today in advance of the annual gathering of the world’s environment ministers opening on 21 February.

The Year Book calls for a global phosphorus assessment to more precisely map phosphorus flows in the environment and predict levels of economically viable reserves. According to the Year Book, the global use of fertilizers that contain phosphorus, nitrogen and potassium increased by 600 per cent between 1950 and 2000. It adds that population growth in developing countries and increased levels of dairy and meat in the global diet are likely to increase fertilizer use further.

The UNEP Year Book 2011 is available at http://www.unep.org/yearbook/2011

Excerpt, Fertilizer and plastic pollution are main emerging issues in 2011 UNEP Year Book, UNEP Press Release, Feb. 17, 2011