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Effects and repercussions of microbeads and microplastic on the order Anura

Brianna N. Love

Hydrology

24 July 2014

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Abstract

The effects of microplastics are known for marine ecosystems and are to an extent known for

fresh water fishes, and birds. However, their effect on frogs has yet to be studied or examined.

Here I examined the main probable effects of microbeads on frogs from the tadpole stage to the

adult stage. The ripple effects are discussed in depth, and possible solutions are also discussed.

Introduction

Microbeads, pieces of plastic that are less than five millimeters in size, are ubiquitous in

marine environments and are becoming more common in freshwater ecosystems. The effects of

microbeads in freshwater are similar to those in marine environments. If these plastics continue

to increase and their effect becomes magnified then the future does not look bright for freshwater

inhabitants, especially frogs and toad. Looking at current research and data about the current

effects microbeads and microplastics affect have on other organisms, and looking at the anatomy

and physiology of frogs, it has been deduced that frogs, which are considered a keystone and

indicator species, and will be greatly affected by these pollutants. Their removal from the

environment would cause a ripple effect felt by every creature, especially humans. The types of

microbeads looked at in this paper are actually smaller than 5mm, since the microbeads in

cosmetics are less than 1mm.

Materials

Internet, Scientific articles, Publisher, Vensim and Word

Results

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Discussion:

Microplastics in the marine environments have been found in countless animals,

including: plankton, worms, birds, and fish. When plankton ingests phytoplankton and other

organisms, these pieces of microplastic are also ingested by them. As these organisms are eaten

the plastics power is magnified up the food chain. During this magnification process, the plastic

attracts other pollutants, which attach to it (University of California). These plastics attract

persistent organic pollutants such as polychlorinated biphenyl, PCBs, and

dichlorodiphenyltrichloroethane, DDT (Y. Mato et al.). These plankton are either directly eaten

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by tadpoles or will be magnified and consumed farther up the food chain, by frogs. A similar

process happens with worms, particularly of the Annelida phylum. While looking at the

lugworm, a marine Annelida, it was noticed that when these worms consumed food, they also

ingested plastic, which is in the sand, there was microplastics “concentrations that compromised

key functions that normally sustain health and biodiversity” (University of California). When

frogs consume worms, their microplastic is passed on to the frogs, thus causing intestinal

blockage and eventually death (Tanaka et al). This same thing goes for birds they also ingest

plastic when feed, because it looks similar to fish and insects they eat. Frogs eat similar foods as

birds, which raises great problems for frogs, since these same issues would occur with them. One

very troubling problem is that these microplastics can enter through fish gills, which means that

they can also enter the external gills of tadpoles. Their gills are the only way that aquatic tadpole

respire. Ergo, if their gills become full of microplastic and are no longer able to respire, they will

die. Additionally if all the tadpoles die off their will no longer be any more frogs (A.J.R. Watts).

Looking at this from a prey perspective, when other predators eat frogs; these predators

are also ingesting these microbeads. This is due to the fact that plastic is not digestible, so these

little pieces of plastic get stuck throughout the digestive system. This means that when frogs

become prey and are digested they leach their microbeads into these predators and can cause the

same issues these frogs face (University of California). Considering that frogs are prey for

animals such as birds, snakes, lizards, and small mammals, the repercussions will be seen

throughout the food web. If the frogs were to disappear from the ecosystem this would lead to an

increase in insects, such as mosquitos, which are carriers of West Nile, malaria, and heartworm

for dogs; among various other diseases (Kriger). This will cause humans to rely on pesticides,

and other pollutants, to remove these pests in turn creates more environmental problems.

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Not only are frogs a keystone species, but they are also an indicator species (Kriger).

Meaning that their presence indicates that it is a healthy environment. Therefore, if frogs were to

disappear from the environment, humans would only know that the environment was unbalanced

(Fouquet). They would not know what is wrong, which means that it would take trial and error to

figure out what is wrong with the environment. Frogs are one of the first animals to be threatened

when an environment starts to decline, so if the frogs are gone then it indicates that this

environment needs to be examined. Tadpoles also play an integral in their environment, because

they are food for larger animals, and keep waterways clean by eating algae (Kriger).

Furthermore, overtime if the frogs are gone humans will not know how terrible the environment

is, because the frogs would have been gone for a while.

In addition to being a vital part of the environment, frogs are also vital to the survival of

humanity. Frogs are food to thousands of people from remote villages in developing countries to

the ultra-wealthy in first world countries (Kriger). Millions are also pets for humans, providing

countless hours of entertainment and education to their owners (Kriger). Frogs also serve a

practical purpose of eating insects humans find annoying and bothersome. Frogs eat millions of

insects around homes and at various organic farms throughout the world. Frogs act as a natural

pest control which helps save farmers money, make food safer and healthier for humans, and

reduce human’s impact on the world they live in (Assauer). Frogs have also lead scientists to

discover countless lifesaving drugs for diseases such as obesity, human immunodeficiency virus,

and cancer (Vanderbilt University Medical Center). Frogs have a plethora of uses to humans and

if they were to go extinct, humanity would possibly lose the cures to the diseases plaguing it.

Looking at the current use of microbeads, which are in thousands of personal care items

predominately hand soaps and facial cleansers. Both of these are frequently used items, which

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add up to more microbeads being added to the environment. In addition to the fact that these

little beads do not biodegrade, but only break into smaller pieces of plastic (Fendall, Lisa S., and

Mary A. Swell). Considering that these products are used since the 1990s, these products have

had a chance to build up in the environment, and will continue until humanity properly recycles

its plastic; this paints a bleak picture for frogs and animals.

The best plan of action to deter the effects of this problem would to first ban the use of

microbeads in cleansers. There are plenty of biodegradable alternatives options such as pumice,

walnut shells, or coarse grain sugar. The next step would be to reduce plastic usage, considering

35 million tons are thrown away per year in America alone (EPA). This plastic along with other

pieces of plastic that are thrown away, create a tremendous source of microbeads. After this, it

would be necessary to recycle what plastic is already available, and pick out what plastic is

nature. Humanities final effort would be to remove what plastic we can from the oceans, because

all earth’s water is connected.

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