hence the plastic softens when heated on flame and restores its original shape at room
temperature; hence, these plastics can easily be molded and shaped into products
such as carpet fibers, credit cards, milk jugs, and floor coverings (Halden 2010).
Plastic fragments vary in size which further classifies them as macrofragmented,
with size 5 mm, microfragmented with size range of 1 μm to 5 mm, and
nanofragmented with size <2 mm. All these are briefly discussed below.
Macroplastics
Macroplastics are the larger units of plastics found especially in marine environment
typically more than about 5 mm. Andrady 2011 showed that the time that
macroplastics stays in the ocean can differ, for example, plastic bag (50 years),
polyethylene bottle (450 years), cigarette ends (1–5 years), polystyrene cups
(50 years), plastic six-pack rings (400 years), and fishing lines (600 years).
Microplastics
Microplastics like most of the other synthetic plastics are solid particles. These
synthetic polymers might have an organized or random shape with size limits
ranging between 1 μm to 5 mm. These are not soluble in water (Frias and Nash
2019). Sharma and Chatterjee 2017 separated microplastics, based on their sources,
into primary and secondary microplastics. The primary microplastics have microscopic dimensions while the plastic formed as result of plastic degradation of larger
particles to smaller ones is known as secondary microplastics. According to the
definition of the joint group of experts on the scientific aspects of marine environmental protection, “plastic particles <5 mm in diameter, which includes particles in
the nano-size range i.e. 1 nm are termed as microplastics” (Beaumont et al. 2019).
Ogunola et al. 2018; Andrady 2011 stated that marine microplastic pollution is
due to primary and secondary sources. Primary microplastics are coming from
different sources, like daily life products, such as toothpaste, cosmetic products,
detergents, cleaning and maintenance products for commercial and industrial use,
shampoos, shower gels, and fibers from the laundry. About 90% of microplastics
might be reserved in wastewater treatment plants (Law 2017; Rhodes et al. 2018)
Within a very short time frame microplastics have tremendously spread into several
different ecosystems such as terrestrial habitats to the depth of the mighty ocean. The
polar regions have also shown positive results for the presence of microplastics. A
number of marine species are at risk of getting entangled in microplastics owing to
their small size which eventually results in physical trauma, starvation, and suffocation. As a result the huge environmental concerns and growing threats to flora and
fauna are raised. Secondary microplastics arise due to the breakdown of larger plastic
materials. Most of the secondary microplastics come from the degradation of larger
plastic substances into microscopic pieces when exposed to high solar radiations and
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temperature; hence, these plastics can easily be molded and shaped into products
such as carpet fibers, credit cards, milk jugs, and floor coverings (Halden 2010).
Plastic fragments vary in size which further classifies them as macrofragmented,
with size 5 mm, microfragmented with size range of 1 μm to 5 mm, and
nanofragmented with size <2 mm. All these are briefly discussed below.
Macroplastics
Macroplastics are the larger units of plastics found especially in marine environment
typically more than about 5 mm. Andrady 2011 showed that the time that
macroplastics stays in the ocean can differ, for example, plastic bag (50 years),
polyethylene bottle (450 years), cigarette ends (1–5 years), polystyrene cups
(50 years), plastic six-pack rings (400 years), and fishing lines (600 years).
Microplastics
Microplastics like most of the other synthetic plastics are solid particles. These
synthetic polymers might have an organized or random shape with size limits
ranging between 1 μm to 5 mm. These are not soluble in water (Frias and Nash
2019). Sharma and Chatterjee 2017 separated microplastics, based on their sources,
into primary and secondary microplastics. The primary microplastics have microscopic dimensions while the plastic formed as result of plastic degradation of larger
particles to smaller ones is known as secondary microplastics. According to the
definition of the joint group of experts on the scientific aspects of marine environmental protection, “plastic particles <5 mm in diameter, which includes particles in
the nano-size range i.e. 1 nm are termed as microplastics” (Beaumont et al. 2019).
Ogunola et al. 2018; Andrady 2011 stated that marine microplastic pollution is
due to primary and secondary sources. Primary microplastics are coming from
different sources, like daily life products, such as toothpaste, cosmetic products,
detergents, cleaning and maintenance products for commercial and industrial use,
shampoos, shower gels, and fibers from the laundry. About 90% of microplastics
might be reserved in wastewater treatment plants (Law 2017; Rhodes et al. 2018)
Within a very short time frame microplastics have tremendously spread into several
different ecosystems such as terrestrial habitats to the depth of the mighty ocean. The
polar regions have also shown positive results for the presence of microplastics. A
number of marine species are at risk of getting entangled in microplastics owing to
their small size which eventually results in physical trauma, starvation, and suffocation. As a result the huge environmental concerns and growing threats to flora and
fauna are raised. Secondary microplastics arise due to the breakdown of larger plastic
materials. Most of the secondary microplastics come from the degradation of larger
plastic substances into microscopic pieces when exposed to high solar radiations and
94
F. Muneer et al.