NowComment
2-Pane Combined
Comments:
Full Summaries Sorted

Ocean Pollution

1 additions to document , most recent almost 2 years ago

When Why
Nov-02-18 Different perspective

Better Research About Sea Turtles Can Help Gauge Ocean Plastic Pollution

October 1st, 2018 by

50 years of plastic waste has brought the world’s oceans to a tipping point in which, by 2050, there will be more plastic in the oceans than there are fish (by weight). Sea turtles are a specific point of concern about ocean plastics, as the intestinal tracts of these large marine animals get blocked when they mistake soft plastics for jellyfish. Headlines about sea turtle deaths on the world’s beaches and community reactions seem to come at us daily. Because of their propensity to ingest debris, sea turtles can be bioindicators of the global marine debris problem, helping us to understand the extent of the plastic problem in our world’s oceans. However, recent research suggests that more can be done to grasp the effects of plastics and other refuse on sea turtles.

sea turtles

Scientists and the public in general are troubled about the increase in ocean trash and the effects of plastics on marine life. Ingestion of marine debris is an increasingly significant problem for marine wildlife and is known to affect more than 170 marine species worldwide. Many marine creatures can’t distinguish common plastic items from food, so they starve because they can’t digest the plastic that fills their stomachs.

Scientific literature about sea turtles tends to correlate their overall health and longevity to the stability and sustainability of the marine environment. Jennifer Lynch of the National Institute of Standards and Technology (NIST) recently published a paper titled, “Quantities of Marine Debris Ingested by Sea Turtles: Global Meta-Analysis Highlights Need for Standardized Data Reporting Methods and Reveals Relative Risk.” In it, she argues that research on turtles over the last 50 years has often only focused on the presence or absence of debris while neglecting to note the amount of garbage found in each turtle gut. Lynch concludes from her own research that trash in turtles should really be handled no differently than any other kind of toxicological issue.

sea turtles

The Various Effects of Plastics on Sea Turtles

Toxicologists often paraphrase Paracelsus, a Renaissance physician who emphasized the value of observation in combination with received wisdom, by saying “the dose makes the poison.”

When doctors determine the risks of environmental toxins on a patient, they base their conclusions on the amount of the substance in question and the patient’s attributes such as weight, age, and size. Lynch explains that, while some people have difficulty imagining plastic as a toxic substance, for turtles, plastic very well could be poisonous to marine life.

“But right now, we don’t know the thresholds,” she said in an article for Science Daily. “We don’t know at what point plastic causes physiological, anatomical, or toxicological impacts on these creatures.”

But the problem may be easier to measure than other exposure issues, provided that the right data is gathered in future studies. Turtles could eventually provide important clues to where garbage is worst. Her research provides some suggestions for improving the science of turtle research.

The NIST researcher says that future sea turtle studies should include all of the following and identify:

  • whether or not toxins were discovered in a sea turtle’s gut
  • how much trash was discovered in the turtles’ digestive systems
  • physiological details like whether the animal was a small hatchling or a large adult
  • the turtle species, as different kinds of sea turtles travel in different parts of the oceans

CleanTechnica Exclusive with Dr. Jennifer Lynch

I contacted Dr. Jennifer Lynch after the recent publication of her research in Environmental Science and Technology. I was curious about the need for the public to understand the toxicology inherent in plastic pollution — how plastic is derived from chemicals that are now playing a large role in the functions of our ocean ecosystems.

Here are her replies.

“Does the public need to know about toxicology of plastic pollution?” Yes, I think it’s important for people that use and discard materials to be aware of what chemicals those materials are composed of, what they break down into, and what impacts the chemicals may have. Our daily lives are incredibly connected with plastics; it’s a material that saves lives (medical advances), helps move people and goods from one place to another (vehicle parts and packaging), makes life more convenient and easy (single-use items), among many other functions. Unfortunately, too much enters our oceans as intentional or accidental litter, and then it has the potential to negatively impact marine habitats and wildlife.

Back to the topic of toxicology, that’s not the focus of my review article. Toxicology is the study of chemical effects on organisms, and I am a Marine Environmental Toxicologist, so I could spend all day talking about this topic. However, my paper was about how much plastic sea turtles were ingesting. The impacts of that ingestion include possible toxicity of chemicals, but more importantly, they also include anatomical physical impacts, like plication, perforation, or obstruction of the gut. These are impacts that we understand better than the toxicity at this point.”

Dr. Lynch sent along a paper she published earlier that discussed toxicology specifically, “Persistent Organic Pollutants in Fat of Three Species of Pacific Pelagic Longline Caught Sea Turtles: Accumulation in Relation to Ingested Plastic Marine Debris.” That paper looked at persistent organic pollutants (POPs), which are human-made chemicals that are extremely persistent, globally transported by atmospheric and oceanic currents, and toxic. The data in that study suggest that sea turtles in the pelagic Pacific are accumulating POPs most likely from their natural prey, not from ingested plastics. The paper concluded with the admonition that these pelagic turtles had a high frequency of debris ingestion, which should highlight a greater concern of the wider problem of plastic pollution in the ocean. In other words, the prey that sea turtles eat contain POPs.

sea turtles

How Should We Rethink Previous Research about Sea Turtles?

Turtles live long lives and inhabit different regions of the globe. Different species feed at different depths of the water, too. Past scientific investigations have also determined that half of all the sea turtles living today have likely ingested plastic debris. Several turtle species are listed as endangered.

Lynch contends that monitoring debris in sea turtles via targeted geographic regions:

“has been disproportionate in the past, with too small a focus placed on the wrong areas. A lot of the focus has been on the Mediterranean, but I found that the turtles in the Central and Northwest Pacific and Southwest Atlantic have a much higher rate of ingestion of plastic. This unfortunately makes many of these past turtle studies worthless to those wanting to know where ocean debris is occurring in large amounts and what species are the most in need of conservation. It can be frustrating.”

Specifically, she suggests that grams of trash per kilogram of turtle (g/kg) is the metric scientists should be using. That kind of standardization in reporting would reveal how much trash the turtles are encountering and which species is being most affected by trash. It also could enable analyses on toxicity.

Lynch noted that much of the data on the topic of turtles and trash is based on autopsies of what were sick or injured animals, which can perhaps throw off data when trying to determine the role of trash in their deaths. “We need to develop noninvasive ways of getting turtle-trash data from healthy individuals,” she said.

Collection methods should be standardized to make cross-lab comparisons easy, she said. Trash pulled from the gut of a turtle should also always be washed and dried to remove excess water as well as excrement, vomit, and blood from weigh-ins.

sea turtles

Final Thoughts

It is important to acknowledge that garbage pieces, especially plastic bits, are unnatural and don’t belong in the ocean, Lynch noted. Exposure to chemicals in garbage is concerning to scientists because it remains unclear how many of the chemicals found in plastic trash are moving through the food chain and how they affect the health of both wildlife and humans who eat fish or live near the coast.

Turtles play a large role in the function of the ocean ecosystem, and several species are listed as endangered, so their conservation is of special concern. Finding ways to gather more efficient information on the amount of plastics that sea turtles inject can lead to valuable solutions for the turtles and the oceans.

“Plastic litter is one of the few contaminants that can be seen with the naked eye,” Lynch said. “The work can be painstaking, and sometimes kind of gross. But it only requires simple lab tools and methods and does not really demand expensive chemical instrumentation. If we improve our methodologies and data collection points and standardize our reporting and analysis, we will likely gain more useful info out of the process for managing our oceans and our garbage.”

The facts point to turtles as being clear indicators of ocean and marine health. Solutions to this environmental crisis, policies, and research funding are desperately needed for the most at-risk species, in the most problematic regions, and in regions that have yet to be monitored that may prove to be even worse, according to Lynch’s research.

Reusable coffee cups are just a drop in the ocean for efforts to save our seas

Films such as A Plastic Ocean, and the huge success of Blue Planet II, have brought ocean plastic pollution firmly into the popular domain. Plastic has become ubiquitous through the world’s oceans, with fragments found in deep ocean trenches and the Arctic ice sheets. Furthermore, pictures of charismatic animals such as whales and turtles consuming or entangled in plastic provide powerful imagery of the problem to the public.

There is no doubt plastic is a big issue. A study in the journal Marine Policysuggests plastic pollution might be reaching a planetary boundary, a term used to describe safe operational environmental limits within which the world can continue to function safely.

Yet, for all the attention given to ocean plastic, it is not the biggest threat to the marine environment. Both climate change and biodiversity loss (much of which is caused by the impacts of overfishing of our oceans) were shown to have exceeded their respective planetary boundaries when the term was first introduced, in 2009. More recent studies also flag climate change and biodiversity as the two core planetary boundaries. Excessively exceeding these for a prolonged period could cause rapid and major changes, such as runaway temperature rises or the collapse of important ecosystem functions.

The latest official report from the UN Food and Agriculture Organisation suggests that 33% of fisheries are overfished and 60% fully exploited, while a controversial new study contends that more than 50% of the area of the oceans is affected by fishing each year.The world’s largest living structure, Australia’s Great Barrier Reef, has undergone successive and large-scale bleaching events in the past few years, with an estimated 50% of coral dead due to bleaching in the past two years. These events, along with degradation of other marine habitats such as kelp forests and seagrass beds, are directly attributable to climate change.

Nor can the effects of plastic on animal populations and their ecosystems be easily determined. Large plastic items break down into smaller microplastics, and many experts think the effects of these may be less than ingestion of larger items, which can cause choking and block digestive systems.

Given these facts, we should ask why overfishing and climate change do not get at least as much attention as plastic when considering the marine environment. We propose this is because plastic pollution provides a “convenient truth”, allowing individuals, corporations and politicians to appear environmentally conscious while ignoring the root of all environmental problems, which is overconsumption of resources.

Large-scale technological solutions, such as the Ocean Cleanup project, provide optimism from the concerned, documentary-watching public that the plastic problem is being addressed. Eliminating plastic straws, promoting reusable coffee cups or having a plastic-free supermarket aisle are easy PR wins for large companies that will barely affect profits. These same token gestures not only attract environmentally conscious customers, but make customers feel they are contributing to an environmental solution.

In truth, much bigger individual behavioural changes need to be made, such as drastically altering our diets to greatly reduce fish and meat, reducing car and aeroplane use and even reducing the number of children we decide to have.

To provide some context, if airlines eliminated single-use plastic, this might save about 20 grams of plastic a person on a typical transatlantic flight. However, each passenger on that plane would be responsible for roughly one tonne of carbon dioxide emissions, around half a million times more greenhouses gasses than plastic waste.

Governments have the power to enforce change, but are reluctant to do so. The world is not on target to meet the Paris climate agreement targets to keep temperature rises to 2C. One reason for this reluctance is the neoliberal agenda, which is still pervasive in most western countries.

Markets will adjust to consumer demand, but this is too little, too late to address the scale and urgency of the environmental threat. In terms of fisheries, the British government has a real opportunity to change fishing practices with Brexit. However, there is an apparent unwillingness to change the status quo significantly. Some foreign boats will probably be allowed into UK waters, either to secure export rights to those countries, or to sell fishing rights. Ultimately, most governments believe in the need for economic growth, beside which environmental concerns will generally be neglected.

While token gestures and technological fixes will have some effect in reducing plastic pollution in the marine environment, as a collective public we need to demand change from large corporations and from governments on all environmental policies. We also need to understand the sacrifices necessary to ensure the future of humanity.

At an international level, we need policies and legislation to prevent excessive overconsumption by individuals and companies, including the promotion of open source ideas around product reuse to maximise re-use and recycling of all products. It is also vital that we find alternative metrics to wellbeing, beyond our myopic focus on economic growth, if we are to reduce consumption and achieve global targets on climate, food production and even plastic waste.

Rick Stafford is professor of marine biology and conservation at Bournemouth University. Peter JS Jones is a reader in environmental governance at University College London

Trump Signs Bill to Improve International Cooperation on Ocean Trash Cleanup

BY HOLLY KELLUM

President Donald Trump extended and expanded what he called a “very important” program to clean up sea-borne waste by signing a bill to boost international cooperation on removing debris from the planet’s oceans.

The Save Our Seas Act of 2018 extended the National Oceanic and Atmospheric Administration’s (NOAA) Marine Debris Program for an additional five years, and directed the State Department and other federal agencies to work internationally to prevent countries from using the ocean as a landfill.

The act charges NOAA to collaborate with other U.S. government agencies to deal with land- and ocean-based sources of the trash, both domestic and foreign.

“People don’t realize it, but all the time we’re being inundated by debris from other countries,” Trump said. “And we will be responding and very strongly.”

In attendance at the Oct. 11 signing ceremony were Sens. Dan Sullivan (R-Okla.) and Sheldon Whitehouse (D-R.I.), the sponsor and co-sponsor of the bill, respectively, whose presence attested to the bipartisan nature of the bill. The House held a voice vote on it, which wasn’t recorded; the Senate passed it unanimously, Sullivan said.

Through its diplomatic channels, the United States has already been putting other countries on notice that the Trump administration will no longer tolerate trash being dumped in the ocean, Trump said.

“And I can tell you that Dan [Sullivan] and Sheldon [Whitehouse] were very insistent on trying to get that into the USMCA, the new agreement that we have with Canada and Mexico. And we’ll be putting it into other agreements also,” Trump said.

Whitehouse concurred and said they were in the process of working it into an agreement with the Philippines, which he named as “one of the worst three” ocean polluters.

For Trump, the issue is an economic one as well as an environmental one. The United States has to clean up the trash that floats into U.S. waters and onto U.S. beaches each year, which not only creates a burden on the government, but hurts businesses along the coast. In one national ocean cleanup, the Ocean Conservancy reported picking up 4,144,109 pounds of trash from over 8,500 miles of coastline.

“This waste, trash, and debris harms not only marine life, but also fishermen, coastal economies along America’s vast stretches,” Trump said. “As president, I will continue to do everything I can to stop other nations from making our oceans into their landfills.”

The act also requires a representative from the State Department, as well as from the Department of the Interior, to join the Interagency Marine Debris Coordinating Committee.

The nonprofit Ocean Conservancy called the legislation a “triumph of bipartisanship,” and praised it for addressing the “the ever-increasing global marine-debris problem.”

Even the American Chemistry Council, an association of chemical manufacturers and other chemistry-related businesses, applauded the passage of the legislation. “This important bipartisan legislation reinvigorates existing programs and includes language recognizing the need to address the lack of waste management systems in developing countries,” it said on its blog.

The Plastics Industry Association also thanked the Trump administration for “demonstrating your commitment to combatting marine debris.”

DMU Timestamp: September 17, 2018 17:21

Added November 02, 2018 at 2:02pm by Grace Wise
Title: Different perspective

Plastics in oceans are mounting, but evidence on harm is surprisingly weak

Unsupported speculation can lead to scarce resources being misdirected when they could be better spent on other environmental issues

Plastics in the world’s oceans are set to treble in the next 10 years, according to a new government report. They are also contributing to a rubbish heap in the Pacific Ocean that is estimated to be as big as France. These are the latest instalments of one of the most prominent environmental concerns of recent years.

It’s not surprising this has become a cause célèbre. Unlike many other human pollutants in the environment, plastic debris is very visible.

Images of birds or fish entangled in plastic are highly emotive – as is the idea that we could be harming ourselves by eating seafood containing tiny pieces of the stuff.

To be sure, this is a big problem. Plastics degrade the environment and we are certainly finding them in increasingly large quantities in our seas and oceans.

This may indeed harm marine life and their ecosystems, but when you look closely at the evidence, it turns out that we are far less sure than it might appear.

There are important gaps in our understanding about plastics. It’s not unreasonable for people to fill these with speculation to some extent – funding for research is limited and we cannot wait for scientific research to provide complete answers before taking action. On the other hand, unsupported speculation can lead to scarce resources being misdirected when they could be better spent on other environmental issues.

Certainly we produce large amounts of plastics each year. They continually end up as waste in the environment, and the polymers they comprise decompose extremely slowly. Large particles fragment into smaller pieces known as microplastics – technically 5mm in diameter or less. These are now recognised as one of the most prevalent human-made pollutants in marine environments across the world.

Microplastics could be accumulating in some places to levels that somehow compromise ecosystems. Deep-sea regions are a probable candidate, for example, though they are also the areas where we have the least information about quantities and effects. We need to do more work to say with confidence whether this is a serious problem.

On the question of how much damage microplastics cause to marine life, we certainly know these particles are readily transported throughout our seas and oceans and there is considerable evidence that organisms ingest them. However, the polymers that make up plastics are of minimal toxicity to marine life.

The question is whether they may cause harm in other ways. It could be that organisms absorb these particles and they accumulate in internal tissues, though it’s not clear whether or not that might be harmful to them. Microplastics may also accumulate in the gut and potentially interfere with processes like nutrient uptake or the passage of waste – or they may just be expelled without any negative effects.

A few studies have shown microplastics being absorbed by marine life in very small amounts, but other studies have found the opposite. We don’t even know whether very small nanoplastics with diameters of less than 1,000 nanometres can be absorbed. The studies that do exist on nanoparticles suggest that such absorption is minimal. In short, the jury is still out on absorption.

If microplastics are not appreciably absorbed, their potential to accumulate in tissues and cause problems is very low. It would also mean they can’t be passed on in any significant way to a predator who eats that organism. If so, it puts microplastics in a different category to toxic substances that end up in the food chain after accumulating in the internal tissues of fish – mercury, say.

There is considerable evidence to suggest that plastic particles are readily released from the gut of organisms without negative effects – and note that researchers have tended to test for concentrations in considerably higher amounts than are found in the environment.

Certainly, questions do remain. Perhaps of greatest importance is whether specific shapes of microplastics – fibres, for example – present particular difficulties for waste moving through the guts of some organisms.

Another concern is around toxic substances like DDT or hexachlorobenzene sticking to microplastics and potentially ending up in places they wouldn’t otherwise reach. Scientists have already found considerable evidence of this. Some people are alarmed that these substances could end up being ingested by marine organisms and harming them as a result.

In one study, the levels of toxic substances in the tissues of marine birds were actually lower when they had ingested plastics (Shutterstock)

Yet most studies have shown that toxicants associated with plastics are either at concentrations too low to be toxic – or that the substances stick too strongly to the plastics to be released into organisms and cause problems.

In one study, the levels of toxic substances in the tissues of marine birds were actually lower when they had ingested plastics. The investigators suggested the toxic substances already present within the bird tissues were sticking to the plastics and being removed. If so, toxic substances attached to plastics might be less of a concern for toxicity to marine organisms than is feared.

Then there are microplastics and the human food chain. We were intrigued by this possibility and conducted an experiment to check. While we cooked in our kitchens, we left open petri dishes with sticky tape to collect dust fallout in the surrounding air.

We compared the amounts of plastic fibres in this dust with the quantities we found in mussels collected around the Scottish coast. The results suggest that while a regular UK consumer might ingest 100 plastic particles a year from eating mussels, their average exposure to plastic particles during meals from household dust is well over 10,000 per year.

In sum, the evidence about the dangers of plastics and microplastics in the marine environment is far from conclusive. There are important gaps in scientists’ knowledge thneed to be filled, particularly where plastic particles are likely to accumulate in large amounts over long periods and how this potentially affects ecosystems.

We must avoid undue speculation and overstating risks, and instead engage with the actual evidence. Otherwise it will detract from our ability to manage plastic pollution in the most effective way and have a clear sense of the right priorities.

Ted Henry is a professor of environmental toxicology and Ana Catarino is an NERC research associate at Heriot-Watt University. This article was first published in The Conversation (theconversation.com)

DMU Timestamp: November 02, 2018 17:13





Image
0 comments, 0 areas
add area
add comment
change display
Video
add comment

Quickstart: Commenting and Sharing

How to Comment
  • Click icons on the left to see existing comments.
  • Desktop/Laptop: double-click any text, highlight a section of an image, or add a comment while a video is playing to start a new conversation.
    Tablet/Phone: single click then click on the "Start One" link (look right or below).
  • Click "Reply" on a comment to join the conversation.
How to Share Documents
  1. "Upload" a new document.
  2. "Invite" others to it.

Logging in, please wait... Blue_on_grey_spinner