Microplastic pollution is the REAL threat to our oceans, warn scientists

Marine experts from the California State University recently pointed out that microplastic pollution has steadily become a major threat to the world’s oceans. According to the experts, microplastics are especially problematic as they are more challenging to manage due to their microscopic size. Microplastics, which measure less than five millimeters, are degraded plastic fibers that end up in the oceans. The researchers cautioned that marine creatures may readily ingest these microplastics as they could mistake them for food.

“Marine debris is everywhere; it’s on the surface of the ocean, it’s on our beaches, and its presence is increasing. We’re seeing more [marine debris] in our oceans now than in the past. The thing that is most disturbing to me is the not the ‘macrodebris’ that we can easily see with our eyes; it’s the ubiquity of microplastics that has completely blown me away. Microfibers and microplastics can displace critters’ natural food and natural behavior. The critter may need to work more and use more energy; it may block their intestinal tracts,” said marine expert Sean Anderson.

“Trash in the ocean, including significant amounts of microplastics, is a pervasive and significant problem in the waters off California as well as around the world. Microplastics are particularly concerning because of their ubiquitous distribution and disastrous impacts on marine life. [Micro plastics] act like a sponge, soaking up additional pollutants from the surrounding waters, only to leach them back out again, oftentimes into animals that have ingested the plastics. This leads to accumulation of toxic chemicals in marine life, even in situations where the animals are far from humans,” marine researcher Krista Kamer said in ScienceDaily.com.

In order to study the effects of microplastics on marine life, Anderson and his team examined digestive systems of multiple crab species along California’s coast. The researchers found that a majority of the species ingested microplastic fragments. In fact, one organism even showed nearly 100 fragments of microplastics in its system. However, the marine experts stressed that more studies are needed to better determine the effects and reach of microplastic pollution.

U.N. report reveals microplastic contamination in fish

Data from the United Nations (U.N.) Environment Project report revealed that more than a quarter of all fish sold around the world were contaminated with microplastics. To carry out the research, a team of researchers examined intestine samples from fish sold at markets in California and Indonesia. The researchers cautioned that consuming high quantities of marine food contaminated with microplastics may cause adverse medical conditions in humans.

The report also warned that people might be breathing in microplastics suspended in the air, which in turn may lead harmful effects similar to car fumes. According to the report, several areas around the world show higher levels of microplastic pollution. East Asia, for instance, was found to have 27 times more plastic particles in the oceans compared with other parts of the world. The report also noted that microplastic pollution may even affect significantly far places such as deep sea sediments and a Mongolian mountain lake. The report was presented last year at the U.N. Environment Assembly in Nairobi, Kenya.

Sources include: 

ScienceDaily.com

Independent.co.uk

Newly-evolved microbes may be consuming plastic waste in the ocean

While scientists, environmentalists, and world leaders scramble to mitigate the effects of plastic pollution, mother nature has solved the problem herself through evolution. In investigating the amount of plastic in the oceans, scientists found that plastic-eating microbes may be helping lessen and prevent the increase of waste in the water, according to a report on NewScientist.com.

Scientists were prompted to investigate this phenomenon after observing that there was less plastic in the ocean than expected, considering the rate at which it is being dumped into the water. One truckload of plastic waste is emptied into the ocean every minute, though scientists found that only a fraction of that amount — one hundredth, to be specific — has actually accumulated in the ocean.

Researchers, led by Ricard Sole at the Universitat Pompeu Fabra in Barcelona, surveyed the North Atlantic gyre in the Atlantic Ocean. This area is vulnerable to accumulating waste due to the strong ocean currents surrounding it, creating vortexes that trap plastic when it is carried into the area. Despite this vulnerability, the amount of plastic found in the area was a tenth to a hundredth less than expected. Moreover, the amount of plastic did not seem to be increasing. The researchers suggested that the discrepancy could be explained by an increase in the population of newly-evolved microbes that are able to biodegrade plastic.

Other scientists are exploring other theories that could account for the disparity. Some, including Linda Amaral-Zettler from the Netherlands Institute for Sea Research, believe it is more likely that microbial colonies growing on plastic pieces could weigh the plastic down and cause them to sink to the seafloor. Either that, or they break into pieces too small to be caught in the nets of research vessels, are swallowed by living organisms, or brought by currents to other areas.

Sole has acknowledged other scientists’ explanations for the “missing plastic”, but explained that the lack of an upward trend in the amount of plastic in the water can only be attributed to a biological response that increased proportionally to the amount of plastic.

Whatever it is that is causing the disappearance of plastic, experts are quick to warn that it is not necessarily a reason to rejoice. Even with biodegradation, the harmful chemicals in plastic could be released and re-enter the food chain. Amaral-Zettler stressed that reducing plastic waste and keeping it from the ocean is still crucial to dealing with the problem of plastic pollution.

“Plastisphere”

The relationship of microbes and plastics has long been an area of interest for scientists, who have discovered that microbes including bacteria, algae, and other single-celled organisms tend to colonize even the smallest pieces of plastic in the water, creating a layer of life called a “plastisphere” on the surface of the synthetic waste. Plastic pieces found in the ocean were found by scientists to carry entire ecosystems on their surface, an article published on the Smithsonian Institute‘s ocean portal said. These ecosystems come complete with primary producers, grazers, predators, and decomposers, not at all different from the communities that thrive in coral reefs.

Amaral-Zettler’s research has found that a piece of plastic as small as five millimeters across could carry a highly diverse population of up to 1,000 different kinds of microbes. Some of them are not normally found in the open ocean, and only survive because they become attached to the plastic. These microbes that exist in plastics could be carried through long distances, potentially invading native microbial populations and affecting the larger organisms that feed or depend on them.

The effects of these plastispheres on the delicate marine ecosystem remain to be seen, though it may take years before any conclusions are found. Follow more headlines about emerging trends in science at FutureScienceNews.com.

Sources include:

NewScientist.comOcean.SI.edu