Chelsea Rochman, an ecologist at the University of California, Davis, has been trying to answer a dismal question: Is everything terrible, or are things just very, very bad?

Rochman is a member of the National Center for Ecological Analysis and Synthesis‘s marine debris working group, a collection of scientists who study, among other things, the growing problem of marine debris, also known as ocean trash. Plenty of studies have sounded alarm bells about the state of marine debris; in a recent paper published in the journal EcologyRochman and her colleagues set out to determine how many of those perceived risks are real.

ecologist = a scientist who studies ecology, environment iːˈkɒlədʒɪst

dismal= miserable, gloomy, depressing ˈdɪzməl 

terrible= awful, dreadful, appalling #wonderful ˈterəbl̩

analysis = examination, study, investigation əˈnæləsɪs

synthesis = mixture, combination, blend #separation ˈsɪnθəsɪs

marine= nautical, maritime, sea, ocean məˈriːn 

debris= wreckage, rubbish, trash, waste, fragment ˈdeɪbriː

collection = group, assembly, gathering kəˈlekʃn̩ 

sound alarm bells = if something rings/sounds alarm bells, it makes you start to worry because it is a sign that there may be a problem ˈsaʊnd əlɑ:m belz

state = condition, situation, circumstance steɪt 

paper = newspaper, article, document ˈpeɪpə 

journal = newsletter, magazine, periodical ˈdʒɜːnl̩ 

set out = start, begin, embark set ˈaʊt 

determine= verify, establish, uncover, reveal dɪˈtɜːmɪn

perceive= understand, comprehend, realize, become aware of pəˈsiːv

Often, Rochman says, scientists will end a paper by speculating about the broader impacts of what they’ve found. For example, a study could show that certain seabirds eat plastic bags, and go on to warn that whole bird populations are at risk of dying out. ‘But the truth was that nobody had yet tested those perceived threats,’ Rochman says. ‘There wasn’t a lot of information.’

speculate= guess, consider, think, contemplate ˈspekjʊleɪt

broad = wide, large, big, comprehensive brɔːd

certain = particular, specific, precise ˈsɜːtn̩

go on to do= to do something after completing something else ˈɡəʊ ˈɒn tu du:

warn = caution, inform, alert, tell, notify wɔːn

at risk = in a dangerous situation ət rɪsk

die out = vanish, perish, become extinct ˈdaɪ ˈaʊt

threat = risk, danger, peril, menace θret

Rochman and her colleagues examined more than a hundred papers on the impacts of marine debris that were published through 2013. Within each paper, they asked what threats scientists had studied-366 perceived threats in all – and what they’d actually found.

examine = investigate, check, research, explore ɪɡˈzæmɪn

actually = really, truly, in fact, in reality ˈæktʃuəli

In 83 percent of cases, the perceived dangers of ocean trash were proven true. In the remaining cases, the working group found the studies had weaknesses in design and content which affected the validity of their conclusions – they lacked a control group, for example, or used faulty statistics.

trash = garbage, waste, rubbish, junk træʃ 

prove = show, demonstrate, verify pruːv 

remaining= the remaining people or things are those that are left when the others have gone, been used, or been dealt with rɪˈmeɪnɪŋ 

weakness = limitation, drawback, flaw, fault ˈwiːknəs

validity= a conclusion, reason…that is based on what is reasonable or sensible vəˈlɪdɪti

faulty= incorrect, defective, flawed. ˈfɔːlti 

statistic= number, figure, measurement, fact stəˈtɪstɪk

Strikingly, Rochman says, only one welldesigned study failed to find the effect it was looking for, an investigation of mussels ingesting microscopic plastic bits. The plastic moved from the mussels’ stomachs to their bloodstreams, scientists found, and stayed there for weeks – but didn’t seem to stress out the shellfish.

strikingly = noticeably, outstandingly, unusually ˈstraɪkɪŋli

investigation= study, search, examination, analysis ɪnˌvestɪˈɡeɪʃn̩

mussel = a small sea animal, with a soft body that can be eaten and a black shell that is divided into two parts ˈmʌsl̩

ingest= swallow, consume, absorb, eat ɪnˈdʒest

microscopic = tiny, minute, atomic, mini #gigantic maɪkrəˈskɒpɪk

bloodstream = the blood flowing in your body ˈblʌdstriːm

stress out = worry, bother, hassle #relax ˈstres ˈaʊt

shellfish = an animal that lives in water, has a shell, and can be eaten as food, for example, crabs, lobsters, and oysters ˈʃelfɪʃ

While mussels may be fine eating trash, though, the analysis also gave a clearer picture of the many ways that ocean debris is bothersome.

Within the studies they looked at, most of the proven threats came from plastic debris, rather than other materials like metal or wood. Most of the dangers also involved large pieces of debris animals getting entangled in trash, for example, or eating it and severely injuring themselves.

bothersome= annoying, troublesome, inconvenient ˈbɒðəsəm

look at = study, investigate, examine ˈlʊk æt 

involve= contain, include, consist of ɪnˈvɒlv 

entangle= (to cause something

to become caught in something such as a net or ropes) twist, tangle, trap ɪnˈtæŋɡl̩

severelyharshly, strictly, brutally, #gently sɪˈvɪəli

injure = hurt, harm, wound, damage ˈɪndʒə

But a lot of ocean debris is ‘microplastic’, or pieces smaller than five millimeters. These may be ingredients used in cosmetics and toiletriesfibers shed by synthetic clothing in the wash, or eroded remnants of larger debris. Compared to the number of studies investigating large-scale debris, Rochman’s group found little research on the effects of these tiny bits. ‘There are a lot of open questions still for microplastic,’ Rochman says, though she notes that more papers on the subject have been published since 2013, the cutoff point for the group’s analysis.

microplastic = extremely small pieces of plastic that are harmful to the environment ˈmaɪ.krəʊˌplæs.tɪk

ingredient= component, element, thing, part ɪnˈɡriːdɪənt

cosmetic= creams, powders, etc that you use on your face and body in order to look more attractive kɒzˈmetɪk

toiletries= things such as soap and toothpastethat are used for cleaning yourself ˈtɔɪlətriz

fiber = a mass of threads used to make rope, cloth, etc ˈfaɪbə

shed= drop, cast, discard ʃed

synthetic = artificial, fake, manmade #natural sɪnˈθetɪk

erode = corrode, destroy, wear down ɪˈrəʊd 

remnant = remainder, leftover, residue ˈremnənt 

investigate = look into something, explore, probe ɪnˈvestɪɡeɪt

cutoff = limit, end. ˈkəˌtɒf

There are also, she adds, a lot of open questions about the ways that ocean debris can lead to sea-creature death. Many studies have looked at how plastic affects an individual animal, or that animal’s tissues or cells, rather than whole populations. And in the lab, scientists often use higher concentrations of plastic than what’s really in the ocean. None of that tells us how many birds or fish or sea turtles could die from plastic pollution – or how deaths in one species could affect that animal’s predators, or the rest of the ecosystem.

creature = animal, living thing, being ˈkriːtʃə 

individual= singular, personal, characteristic ɪndɪˈvɪdʒʊəl

tissue = the material forming animal or plant cells ˈtɪʃuː

cell = group, unit, section sel

lab = laboratory, workshop, test center læb 

concentration= the amount of a substance in a liquid or in another substance kɒnsənˈtreɪʃn̩

turtle = a large reptile with a hard round shell, that lives in the sea ˈtɜːtl̩

the rest of = what is left after everything or everyone else has gone, been used, dealt with, or mentioned ðə ˈrest ɒv

‘We need to be asking more ecologically relevant questions,’ Rochman says. Usually, scientists don’t know exactly how disasters such as a tanker accidentally spilling its whole cargo of oil and polluting huge areas of the ocean will affect the environment until after they’ve happened. ‘We don’t ask the right questions early enough,’ she says. But if ecologists can understand how the slow-moving effect of ocean trash is damaging ecosystems, they might be able to prevent things from getting worse.

relevant= related, pertinent #unrelated ˈreləvənt 

disaster = tragedy, catastrophe, calamity dɪˈzɑːstə 

tanker = a vehicle or ship specially built to carry large quantities of gas or liquid, especially oil ˈtæŋkə

spill = leak, drop, fall, drip #absorb spɪl 

cargo= the goods carried in a ship or plane ˈkɑːɡəʊ

prevent= stop, avoid, block, inhibit #permit prɪˈvent

Asking the right questions can help policy makers, and the public, figure out where to focus their attention. The problems that look or sound most dramatic may not be the best places to start. For example, the name of the ‘Great Pacific Garbage Patch‘ – a collection of marine debris in the northern Pacific Ocean – might conjure up vast floating trash island. In reality though, much of the debris is tiny or below the surface; a person could sail through the area without seeing any trash at all. A Dutch group called ‘The Ocean Cleanup’ is currently working on plans to put mechanical devices in the Pacific Garbage Patch and similar areas to suck up plastic. But a recent paper used simulations to show that strategically positioning the cleanup devices closer to shore would more effectively reduce pollution over the long term.

figure out = understand, discover, work out, solve ˈfɪɡə ˈaʊt

attention = mind, concentration, awareness, consideration əˈtenʃn̩

dramatic = impressive, extraordinary, remarkable drəˈmætɪk

patch = area, space, plot of land pætʃ

conjure st up= to make something appear as a picture in your mind = evoke. ˈkʌndʒə snt ʌp

vast = huge, massive, enormous #small vɑːst 

float = to stay or move on the surface of a liquid without sinking fləʊt

in reality = really, actually, in fact ɪn rɪˈælɪti

surface outside, shell, façade ˈsɜːfɪs

sail = to travel on or across an area of water in a boat or ship seɪl

mechanical = affecting or involving a machine mɪˈkænɪkl̩

simulation= model, imitation, virtual realitysɪmjʊˈleɪʃn̩

strategically= deliberately, intentionally, purposefully strəˈtiːdʒɪkl̩i

shore = coast, seashore, coastline ʃɔː

‘I think clearing up some of these misperceptions is really important,’ Rochman says. Among scientists as well as in the media, she says, ‘A lot of the images about strandings and entanglement and all of that cause the perception that plastic debris is killing everything in the ocean.’ Interrogating the existing scientific literature can help ecologists figure out which problems really need addressing, and which ones they’d be better off – like the mussels – absorbing and ignoring.

clear up = explain, elaborate, solve. ˈklɪər ʌp 

misperception= misunderstanding, confusion mɪspərˈsepʃən

perception = view, opinion, assessment pəˈsepʃn̩ 

interrogate = question, interview, probe= to ask someone a lot of questions for a long time in order to get information, sometimes using threats ɪnˈterəɡeɪt

literature= all the books, articles, etc on a particular subject ˈlɪtrətʃə

address = tackle, focus, deal with #ignore əˈdres 

be better off = to be in a better situation, if or after something happens bi ˈbetər ɒf

absorb = if something absorbs light, heat, energy,or noise, it takes it in. əbˈzɔːb