Marine Pollution Exam 2

what percentage/abundance of plastic sinks?

~66%

what percentage/abundance of plastic floats in the water column?

15%

what percentage/abundance of plastic ends up on shorelines?

the remainder (~19%)

what type of litter is most prevalent in marine environments?

plastic

how are plastics in the sea quantified for visual seafloor surveys?

performed by snorkelers and divers commissioned by specialized programs, involves waters shallower than 10 m, deeper waters can be sampled using methods similar to those for research

how are plastics in the sea quantified at the water surface?

conducted by individuals on ships, aircraft, or platforms, only reliable for pollutants measuring between 30-40 cm

how are plastics in the sea quantified in the water column?

no great methods

what depth is the limit for divers and snorkelers?

> 10 m

what are the benefits of using plastic?

cheap, malleable, flexible, strong, waterproof, shortage of metal during WWII

what is thermal oxidation?

process that uses heat to remove pollutants from waste gas or to create a thin layer of oxide on silicon

when does thermal oxidation occur?

when silicon is heated in the presence of oxygen or steam

how does thermal oxidation compare to photodegradation?

it’s slower

size range for megadebris

> 100 mm diameter

examples of megadebris

vehicle parts, furniture, lobster pots, trawls

size ranges for macrodebris

> 20 mm diameter

example of macrodebris

similar to megadebris

size ranges of microdebris

< 2 mm diameter

examples of microdebris

breakdown of larger plastic objects

primary microplastics

small plastic particles with industrial uses (cosmetic, hygiene, medical use, clothing)

secondary microplastics

plastic particles derived from larger plastic waste

effects of ingesting plastic on marine organism digestion

plastics may resemble natural food source or may be recognized as materials ingested by food source, can inhibit digestion, block gut/gullet, falsely decrease hunger stimulus, reduces gut storage capacity, prevents gastric enzyme secretion, less energy for other processes, results in malnutrition and starvation, steroid hormone production, ovulation, decreased body-fat reserves

what does the Extended Producer Responsibility (EPR) mean?

pollutant product is the producer’s responsibility after becoming waste, encourages recycling and recovery of pollutant

plastarch

biodegradable, made from corn starch

polyhydroxyalkanoate (PHA)

biodegradable, made from bacteria fed with organic matter, waste treatment benefit

polyhydroxybutyrate (PHB)

only biodegradable in terrestrial environments

polylactic acid

biodegradable in specific conditions, made from fermented starches (lactic acid)

what two elements are considered essential plant nutrients and can also become pollutants?

phosphorus and nitrogen

what compound is highly toxic to aquatic organisms?

ammonia

alkaline builders

major components of synthetic detergents that break down organic matter, may be non-ionic, anionic, cationic, or bleach

surfactants

components of some detergents that lowers liquid surface tension, have hydrophobic and hydrophilic parts (amphiphilic), highly toxic, can bind sediments, and can mobilize insoluble hydrophobic pollutants (disrupt legacy pollutants)

what are the differences between light-colored and thick crude oil?

light-colored crude oil is made of more low molecular weight hydrocarbons and can be poured easily at room temperature, thick crude oil is tar-like and must be heated for transfer

what are the characteristics of refined hydrocarbons in relation to crude oil?

crude oil is a complex mix of hydrocarbons collected from geological reserves in which oil is extracted, contains differing chemical bonds, lengths, extents, and co-occurring compounds

what are the characteristics of natural oil seepage?

makes up an estimated 30-46% of total oil input, due to geological deposits leaking, affected zone is constantly exposed and is stabled

what are the characteristics of atmospheric seepage?

encompasses ~14% of total oil input, affects large areas, mostly from incomplete hydrocarbon combustion of fuel

what are the functions of drill mud?

pumped into the shaft and carries the rock cuttings to surface, cools, lubricates, and pressurizes drill head

oil mops

exploits hydrophobic properties of oil, uses ropes or rollers covered in “oil-loving” plastics to collect and lift oil out of the water, oil is then squeezed out and deposit it in the collecting vessel

oil skimmers

exploits oil’s natural tendency to float on top of water, uses a weighted funnel that floats at the water surface and channels the oil inside, oil can then be pumped into the collecting vessel

dispersants

special chemical formulations applied to oil spills that breakdown the slicks into droplets (break oleophilic bonds), droplets dispersed throughout the water columns

benefits: elimination as hazard for mammals and birds, elimination of effects on beaches, increased surface area of oil for better breakdown by microbes, some dispersants include bacterial cultures

disadvantages: increased chance of ingestion or grill contact by fish and filter feeders, slicks may reform if not adequately dispersed in environment

which marine habitats are the most sensitive to oil spills?

estuaries and coral reefs

which marine habitat is more resistant to oil spills?

rocky shores

UV and X-ray radiation

emitted by sun and absorbed by atmosphere, pollutants in the atmosphere can create holes in the protective ozone layer, UV radiation has been shown to increase mutation rates in plankton and skin cancer in humans

nuclear radiation

produced from nuclear reactors and for scientific/medical uses, Includes α, ß/neutron particles, and γ-rays, neutron radiation can make other cause something else to be radioactive, emits particles/high energy photons as it sheds energy to form a more stable nucleus, half life (time for the rate of emissions to decrease by 1/2)

low-level wastes

gloves and protective gowns required when handling radioactive material, diluted radioactive reagent solutions, biological material, and shielding that has been radiated mildly, disposal and treatment is difficult due to the diversity and bulkiness of the waste, typically encased in concrete drums above or below ground, concerns about limited space

intermediate-level wastes

typically from military and nuclear power industry, shielding required, chemical treatment for stability or concentration of the waste is followed by encasement in glass or concrete blocks, short half-life materials are stored similarly to low-level waste, but high half-life compounds are buried deep underground

high-level wastes

special handling required, shielding and cooling needed, radioactive components may be separated out to create fresh fuel or useful radionuclides, may be treated and stored in other countries, ultimately responsibility of waste-generating country

biosecurity

the regulation and prevention of non-native species introductions into an ecosystem, may cause disease, be pests, or out-compete other species

what are “take back” programs?

unused medications can be recycled and reused or incinerated

properties of pharmaceuticals

used for treating various ailments, from cuts to cancer to mental health, may be a part of many daily-used products, first ones to be largely synthesized were alkaloids (ex: morphine) in Germany (1827), later followed by insulin (1921) and penicillin (1928), additional uses in farmland and animals new molecular entities are constantly being produced

ecopharmacology

study of the effects of pharmaceuticals in the environment and their ultimate fates

fate and effects on marine ecosystem and human health

high complexity of pharmaceuticals creates difficultly identifying environmental effects and long term organism health, toxic effects of active pharmaceutical ingredients are not well known more many substances, bioaccumulation can occur, antibiotics can disrupt biological processes of good microbes and promote resistance of disease-causing organisms

what compounds require legislation?

radioactive compounds

what compounds are immune from legislation?

certain compounds with little risk to the environment (peptides, aa, vitamins), vaccines, and herbal treatments

characteristics of endocrine-disrupting compounds (EDCs)

exogenous agents that interfere with the synthesis, secretion, transport, action, or elimination of natural hormones in the body that are responsible for the maintenance of homeostasis, reproduction, development and/or behavior

may impair or mimic estrogen/testosterone production and/or interfere with the function of the thyroid, organisms are more susceptible during early life, particularly during tissue formation, low concentrations can cause environmental issues (hormone affinity), dose-response is non-linear and can be impacted by a variety of factors

how is chloramine different from the other chlorine compounds used to disinfect drinking water?

less liable to photo degradation but produces more toxic products, additionally used to disinfect ballast water, prevent biofilm formation, and sewage treatment

what are the disadvantages of perchlorates?

water-soluble and mobile, strong oxidizers, persistent, bioaccumulate, and produce sub-lethal effects

how does fracking affect the matrix?

causes small cracks in the rock that leads to expansion or shattering of the matrix

how does light pollution affect sea turtles?

may be deterred from laying eggs on beaches with high artificial light, may delay egg-laying or cause them to migrate to less suitable areas, hatchlings may migrate towards the bright lights up the beaches instead of towards the moonlight ocean

how does light pollution affect zooplankton?

squid fishing with artificial lights on boats may disrupt zooplankton migration, instead of migrating to the surface during the night to feed on phytoplankton, they will stay in the deeper, nutrient poor areas