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Micro-plastics: An invisible danger to human health



Microplastics are small plastic pieces ranging between the size of 1-5 micrometre (µm). Because of their small size and their continuity, it has the potential to spread throughout all parts of our environment. These are ubiquitous environmental contaminants leading to inevitable human exposure. It can enter our bodies through ingestion, inhalation and dermal contact. It has already been found in various human foods, beers, drinking water, honey, seafood, sugar, table salt etc. It is demonstrated that marine organisms including zooplanktons, bivalves, crustaceans, worms, fish, reptiles etc. ingest microplastic. Around 2% to 40% of fishes were found to be contaminated with microplastic. It can reach our stomach and due to its size , these are either excreted, get entrapped in intestinal lining and stomach or move freely in body fluids like blood, thereby reaching various organs and tissues of body. To tackle this serious issue of microplastic pollution in environment and in human health, various effective policies must take under consideration all stages of lifecycle of plastic connecting producers to users and ultimately to waste managers. Thus, we have to seem for potential effects of microplastics in living beings, which specializes in the pathways of toxicity and exposure, way to reduce microplastic pollution, sources of invisible plastics. Present work was conducted to explore the possible threats of micro as well as nanoplastic particles to humanity as well as to our ecosystem. Under this study we summarized various aspects of this critical issue, which provide better scientific knowledge for future research.
CGC International Journal of Contemporary Technology and Research
ISSN: 2582-0486 (online) Vol.-3, Issue-2 DOI: 10.46860/cgcijctr.2021.06.31.191
© All Rights Reserved to CGCIJCTR Page 191
Microorganisms as vital additives in Waste
Dr. Renuka1*, Khushboo Gupta2,
1Department of RISE, 2Chandigarh College of Technology
Chandigarh Group of Colleges, Landran, Mohali
Email ID:
Abstract: Microorganisms play necessary roles within the maintenance of the many natural and synthetic development within
the environment. They serve positive functions that build life easier and higher for man. one in every of such areas that
microorganism’s area unit adopted is in waste management. the right disposal of the voluminous waste that humans generate
in their daily activities may be a nice challenge that government and environmental agencies area unit unceasingly seeking
higher ways that of addressing. a crucial method of with success combating this menace is thru the utilization of
microorganisms. Thus, this paper examines the varied applications of microorganisms within the management of municipal
waste. It reviews the varied roles of microorganisms within the atmosphere, like in waste product and soil treatment, energy
generation, oil spillage and hot contamination. It conjointly discusses waste generation and management ways, and a few
specific uses of microorganisms (bacteria, fungi, algae, virus and protozoa) in waste management. It concludes by light some
recent advances in microbiological waste management.
Indexed Terms- Micro-Organisms, Waste Management, Composting, Waste Water, Anaerobic Digestion, Municipal Solid
Waste, Environmental Pollution.
Micro-Organisms are present everywhere in the
environment where they play an important role. So many
Microbes have unique adaptation to some specific
environmental conditions like one who inhabited dead sea
and pink snow caused by Chlamydomonas nivalis..
Microbes play a great role in Natural Recycling of living
Materials. Bio-degradable substances are those which are
naturally produced and can be easily broken down by living
organisms like Bacteria and Fungi. Micro-organisms have
been very indispensable in searching for solutions for
various problems which mankind has encountered in
maintaining the quality and for stabilizing proper ecosystem.
Even they have been used to maintain a proper and positive
effect in human and animal health, municipal and industrial
waste treatment, genetic engineering, etc. In India with a
population of 130 Crores, Waste generation and Disposal is
the most difficult challenge faced. The main sources of
waste are industrial, agricultural and domestic waste’s and
is grouped into all three forms of Matter (Solid, Liquid and
Gas). The Waste which creates most of the problem is Solid
and Liquid Waste’s. Out of all waste, Plastic is the most
dangerous waste as it is Non- Biodegradable.
It requires a lot of chemical synthesis to convert Natural
Resources into other useful form. It even leads to pollution
while producing any Product. All the process of converting
these Natural Resources involve use of Micro-Organisms
(Bacteria, Fungi, etc.). Micro-Organisms are very important
for the environment as well as Human. They play a very
important role in all the aspects like carbon and nitrogen
cycle, even in recycling the natural resources. Also, Micro-
Organisms are vital as they perform some very important
roles such as recycling other organisms’ dead materials and
waste products through decomposition. Micro-Organisms
give a main of its quality in higher- order, multi-cellular
i. Sewage Treatment: Most of all oxidative sewage
treatment processes merely depends upon a large range
of Micro-Organisms to get oxidized in small organic
constituents which are not manageable for the process of
sedimentation or flotation. Anaerobic Micro-Organisms
are there for reducing big solid Globules, producing
methane gas (amongst other gases) and a sterile
mineralized residue.
ii. Soil treatment: The atmospheric nitrogen fixation leads
to nitrogen cycle or nitrogen fixation. Diazotrophs can
be used for this. Nutrients and minerals are generally
produced my microorganisms in the soil which is
readily available for plants which helps in formation of
hormones with triggering growth. Diversification of
microbes results in more yielding varieties and less
plant diseases.
iii. Energy Generation: In Fermentation, Micro-organisms
help to produce ethanol. In Bio-gas Reactors Micro-
Organisms helps in producing Methane. Many Scientists
are still researching over it and recently on the use of
Algae to produce fuel and searching on key factors
leading to bacteria for fuel generation by agricultural
and urban waste.
iv. Oil Spillage and Radioactive Contamination: There are
various type of Bacteria’s in this environment that could
clean various pollutants like Spilled Petroleum. When
there is an oil Spill ,Alcanivorax ,a specific strain that
increases population.
v. A specific Strain called ALCANIVORAX increases
population due to the large amounts of Nutrients which
are provided them. Some bacteria helps in growth of
nanowires and can be used in immobilization of harmful
CGC International Journal of Contemporary Technology and Research
ISSN: 2582-0486 (online) Vol.-3, Issue-2 DOI: 10.46860/cgcijctr.2021.06.31.191
© All Rights Reserved to CGCIJCTR Page 192
Fig. 1: Site view
The nano wires grown by some types of bacteria can also
be used to immobilize harmful elements like uranium
and keep them away from spreading. Recently in Michigan
State University ,researchers stated that geobacter bacteria
found naturally in soil which electroplates uranium which is
insoluble and undissolved and contaminate groundwater..
Solid wastes may be outlined as non-liquid and
nongaseous product of human activities, thought to be
being useless. It might take the sorts of refuse, garbage and
sludge. the amount and rate of solid waste generation in an
area depends on the densely populated area, socio-
economic standing of the voters and also other sorts of
industrial activities occurring within the space. Wastage
leads to polluted environment with odour nuisance.It
become breeding place for number of flies and insects.
They'll conjointly cause hearth hazards excluding
being eyesores and sources of unpleasant odours,
terribly soft, refuse is drop in drainages or
canals and on watercourses with freedom. The
unsanitary mode of wastes disposal, like open
elimination, excretion in open and also the selling of
refuse in pits, rivers and evacuation channels area unit
widespread and also the resultant contamination of the
setting contributes to environmental degradation.
Waste management is that the assortment, transport,
process or disposal, managing and observance of waste
materials to minimize its consequences on humans and
atmosphere. Solid waste treatment techniques act to scale
back the volume and toxicity of solid waste, reworking it
into a lot of convenient and/or useful type. In Awosusi,
waste management is viewed as a method of supply
reduction, refuse utilisation, controlled combustion and
controlled landfill; energy generation from waste (energy
recovery) and finally, solid waste disposal, if the
aforementioned don't provide applicable resolution. variety
of processes square measure concerned in effectively
managing solid waste. These embody observance,
collection, transport, processing, recycling, burning,
landfilling and composting. This embodies differing types of
ways like follows thermal treatment (whereby the method
use heat to treat waste materials) like burning, chemical
action and transmutation, and open burning; dumps and
landfills like sanitary landfills, controlled dumps and
bioreactor landfills; biological waste treatment like
composting and anaerobic digestion.
Fig. 2: Graphical representation of solid waste
The Micro-Organisms that inhabit the aerobic
biological treatment systems embody bacterium, and
other microbes. The expansion of any type of Micro-
Organisms during an industrial wastage disposal system can
rely on the chemical characteristics of the economic waste,
the environmental limitations of the actual waste system and
therefore the organic chemistry characteristics of the Micro-
Organisms. All of the Micro- Organisms which grow during
a given industrial waste disposal system contribute to its
over-all characteristics, each smart and unhealthy.
It is important to acknowledge the role created by every
form of organism to total stability of the organic wastes if
the waste treatment system is to be properly framed and
executed for max potency.
Bacteria is the basic biological unit in waste water
treatment. Due to variation in chemistry and nature of this
,it can metabolize most . Obligate aerobes. and facultative
microorganism can found altogether aerobic waste
treatment systems. Growth of any explicit species depends
upon its competitive ability to get a share of the on the
market organic material within the system. Bacterial
predomination can usually divide itself into two important
groups: the microorganism utilizing the organic compounds
within the waste, and also the microorganism utilizing the
lysed product of the primary cluster of Micro-Organisms.
The microorganism utilizing the organic compounds within
Municipal Solid Waste
CGC International Journal of Contemporary Technology and Research
ISSN: 2582-0486 (online) Vol.-3, Issue-2 DOI: 10.46860/cgcijctr.2021.06.31.191
© All Rights Reserved to CGCIJCTR Page 193
Fig. 3: Work flow
the waste are the foremost necessary cluster and can verify
the characteristics of the treatment system. Species with
fastest growth rate and having the ability for utilization of
organic matter in bulk can predominate. The extent of
secondary predomination can rely upon the length of
starvation. Depletion of the organic substrate is followed-
by death and lysis of the predominate microorganism
unleash of the cellular components of the microorganism
permits alternative microorganism to get older. Since all
biological treatment systems are usually overdesigned as a
security issue, secondary predomination can occur. apart
from the metabolic characteristics of the bacteria, the
foremost necessary characteristic is their ability to
flocculate. All of the aerobic biological waste treatment
systems rely upon the activity of the Micro-Organisms and
their separation from the liquid section for complete
stabilization. It was 1st thought that activity was caused by
one microorganism species, Zoogloeal ramigeria, however
recent studies have shown that there are many alternative
microorganisms that have the flexibility to flocculate. it's
been postulated that all microorganism have the flexibility to
flocculate beneath bound environmental conditions. The
prime factors poignant flocculation are the surface charges
of the microorganism and their energy. The electrical
surface charge on microorganism grown in dilute organic
waste systems has been shown to be below the important
charge for auto-agglutination, 0.02 volts. this implies that
motion provides spare energy to beat the loathly electrical
forces when 2 microorganism approach one another and to
allow the Van der Waal forces of attraction to predominate
and hold the two microorganisms along. Autoagglutination
doesn't ensue if the energy of the system is sufficiently high
to permit the microorganism to multiply and to be speedily
motile. Autoagglutination, or activity, happens solely when
the bacteria lack the energy of motility to beat the Van der
Waal forces. Once floccule has begun to kind, a number of
the bacteria die and lyse. Associate in Nursing insoluble
fraction of the Micro-Organism cell is left that is primarily
polyose. The older the floccule becomes, the additional
polyose builds up and also the less active Micro-Organism
ar entrained in it.
Fungi play a vital role within the stabilization of organic
wastes just exactly the Micro- Organism,fungus will
metabolize ususally each style of chemical mixtures found
in industrial effluents.. The fungi have the potential ability
to predominate over the Micro- Organism however they are
doing not except beneath uncommon environmental
conditions. The thin nature of most of the fungi found in
industrial wastes makes them undesirable since they are
doing not kind a decent compact floccule and settle simply.
For this latter reason, considerable efforts are exhausted to
form the environmental conditions additional favourable for
Micro-Organism predomination than for thin fungi.
The thin fungi predominate over the Micro-Organism
at low atomic number 8 tensions, at low pH, and at low
element. Low atomic number 8 tension results from an
occasional atomic number 8 offer .. Under reduced atomic
number 8 levels, metabolism doesn't proceed to greenhouse
emission and water however stops with the formation of
organic alcohols, aldehydes, and acids. If the system lacks
spare buffer, the organic acids depress the hydrogen ion
concentration to the more favourable vary for fungi. Thus, it
is often seen that low atomic number 8 tension and
hydrogen ion concentration are often reticulated. several of
the fungi grow well at hydrogen ion concentration four to
five whereas few Micro-Organism are able to grow to a
tolerable degree to vie. Fungi need less element than Micro-
Organism per unit mass of living substance. In element
deficient wastes, the fungi ar able to synthesize additional
active masses of living substance from the wastes than ar
the Micro-Organism and predominate. Micro- Organism
average some 10% to 12% element whereas fungi vary
from five to six element. beneath traditional environmental
conditions fungi are going to be present and can aid within
the stabilization of the organic matter. However the fungi
are of secondary importance and cannot predominate.
CGC International Journal of Contemporary Technology and Research
ISSN: 2582-0486 (online) Vol.-3, Issue-2 DOI: 10.46860/cgcijctr.2021.06.31.191
© All Rights Reserved to CGCIJCTR Page 192
The algae are the third sort of biological plants that play a
neighbourhood within the over-all stabilization of organic
wastes. Since the alga acquire their energy for synthesis from
daylight, they are doing not ought to metabolise the organic
compounds just like the Micro-Organism and also the fungi.
to create living substance the alga primarily utilizes the
inorganic parts of the wastes, for instance, ammonia,
greenhouse emission, phosphate, magnesium, potassium, iron,
calcium, sulphate, sodium and alternative ions. it's doable to
possess alga and also the Micro-Organism predominate along
since they are doing not utilize the same waste parts.
Throughout living substance synthesis, the alga unleashes
atomic number 8 that is taken by the Micro-Organism to
motivate complete aerobic stabilization of the organic matter.
within the absence of daylight, the alga must obtain the
energy needed to remain alive from the metabolism of
organic matter within the same manner as Micro-Organism
and fungi. This organic matter usually comes from hold on
food among the cell however in some Protoctista species it
will come from the organic material within the wastes.
Generally, solid waste will broadly speaking be classified
into perishable and non- biodegradable. The biodegradables
(biowastes) square measure those solid wastes generated, that
can be rotten by microorganisms and doesn't constitute major
sources of pollution for a protracted amount of your time.6
They embody paper product and wastes of plant origin,
wastes of animal origin (faecal matter, carcass, droppings,
and poultry waste products).
These teams of solid waste even if they're simply
degraded by organism in bottom time, give off offensive
odour and represent nuisance to the aesthetic setting quite the
non- biodegradable solid wastes. They can conjointly
represent an honest environment for the thriving of morbific
microorganisms that might simply foul fresh food product
and sources of water within the urban cities in India. On the
opposite hand, non- biodegradable solid wastes aren't
degradable by microorganisms. this means that different
means of treatment like burning, landfill, and use square
measure used as ways in which of disposing them.
Examples of this cluster of solid wastes square measure
solid wastes of scientific discipline and smelting industries
(abandoned vehicles, motor cycles, vehicle half and scrap
metals, iron, zinc, atomic number 13 sheets and different
metals, machine parts); solids wastes of construction
industries (sand, gravel, hydrocarbon wastes, concrete and
waste building materials); solid waste of plastic industries
(plastic buckets, cable insulators, tyres, chairs, tables, plastic
wrap luggage, plastic bottles, cutleries, sachet water
containments, etc.) and glass product.
Management of solid waste reduces or eliminates
adverse impacts on the setting and human health and
supports economic development and improved quality
of life. Composting is that the most often used
biological solid waste treatment methodology that is
that the controlled aerobic decomposition of organic
waste materials by the action of tiny invertebrates and
microorganisms. Composting may be a technique
during which organic waste materials (food, plants,
paper) square measure rotten so recycled as compost to
be used in agriculture and landscaping applications.
The foremost common composting techniques embody
static pile composting, vermin- composting, windrow
composting and in-vessel composting.
Waste is any material, that have very little or no worth
to producer or client. Humans with nearly all activities
produce waste. the most important element of municipal
solid waste represents organic fraction, principally from
domestic, agricultural and industrial sources. There are a
unit many alternative strategies of managing municipal
waste streams. These include physical, chemical and
biological strategies. standard waste management practices
typically involve one negative consequence or the
opposite. This necessitated the look for and development
of biological techniques, including the employment of
microorganisms that manufacture environmental-friendly
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© All Rights Reserved to CGCIJCTR Page 193
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... One of the least visible and therefore one of the most dangerous pollutants is plastic. Plastics can be found on the ocean floor [2] and in marine animals [3]; microplastics pollute drinking water supplies [4] and even unborn babies [5,6]. ...
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This document describes the results of the study contributing to the methods and tools applicable in plastic waste sorting systems that exploit the multistatic ultra-wideband impulse radar enforced with a deep learning signal processing back-end. The novelty of the research is the use of synthetic data for the development of a trained neural network before real data are available, and the use of a multistatic radar for the improvement of the training data set. The study results are described in multiple publications; the current paper shows the applicability of the described approach. The main results are as follows: a monostatic impulse radar can be used for the determination of material properties, such as thickness, dielectric permittivity, and losses, with limited accuracy; multistatic radar configuration increases the accuracy of the material property estimation; an open source finite difference time domain simulator can be used to simulate electromagnetic wave propagation in dielectric structures in order to generate synthetic data for development of optimized artificial neuron network structures used for the estimation of dielectric material properties, and the developed network can successfully be used for multistatic radar data processing.
... Microplastics (MPs) are small plastic fragments with a diverse range of sizes, shapes, colours, and types of plastic material. They have different sources, specific gravity, particle density, and particle sizes <5 mm and are classified as primary and secondary plastics (Fu and Wang, 2019;Sharma and Kaushik, 2021;Simon et al., 2018). Global demand for plastic consumption is increasing continuously owing to urbanization worldwide leading to an increase in rates of its production (Bhattacharya et al., 2018;Chauhan and Wani, 2019). ...
Synthetic plastics, which are lightweight, durable, elastic, mouldable, cheap, and hydrophobic, were originally invented for human convenience. However, their non-biodegradability and continuous accumulation at an alarming rate as well as subsequent conversion into micro/nano plastic scale structures via mechanical and physio-chemical degradation pose significant threats to living beings, organisms, and the environment. Various minuscule forms of plastics detected in water, soil, and air are making their passage into living cells. High temperature and ambient humidity increase the degradation potential of plastic polymers photo-catalytically under sunlight or UV-B radiations. Microplastics (MPs) of polyethylene terephthalate, polyethylene, polystyrene, polypropylene, and polyvinyl chloride have been detected in bottled water. These microplastics are entering into the food chain cycle, causing serious harm to all living organisms. MPs entering into the food chain are usually inert in nature, possessing different sizes and shapes. Once they enter a cell or tissue, it causes mechanical damage, induces inflammation, disturbs metabolism, and even lead to necrosis. Various generation routes, types, impacts, identification, and treatment of microplastics entering the water bodies and getting associated with various pollutants are discussed in this review. It emphasizes potential detection techniques like pyrolysis, gas chromatography-mass spectrometry (GC-MS), micro-Raman spectroscopy, and fourier transform infrared spectroscopy (FT IR) spectroscopy for microplastics from water samples.
Plastic leachates are priority pollutants considered dangerous to health. Large amounts of plastic waste are disposed of daily with less biodegradability. These plastic materials often disintegrate into tiny sizes that can leach into the groundwater, agricultural soil, and foods. Chemical leachates from plastic additives like Bisphenol A (BPA), plasticisers (phthalates and their esters), flame retardants, antioxidants, acid scavengers, and lubricants do not covalently bind tightly to the plastic moiety, and thus break away through various processes into the environment, food, water, air, skin, and the nose, where they facilitate endocrine disruption and other serious health disorders. Synthetic plastic polymers that are classified according to their physical and chemical properties into polyethylene terephthalate, high-density polyethylene, polyvinyl chloride, low-density polyethylene, polypropylene, polystyrene, and polycarbonates are produced readily, littered due to their high demands. Hence, the use of glass material, paper, jute, and other bioplastics made of renewable materials is encouraged to assuage the health risk implication of plastic pollution. Biodegradable plastics manufactured from lignin (liquid wood), a by-product in the paper industry, polyesters like aliphatic and polyhydroxyalkanoate (PHA) polyesters, and starch-based polymers comprising polymeric material made from milk casein and chicken feathers are considered safer than the man-made plastics readily available. This chapter, therefore, contributes to the sensitisation and creation of awareness to encourage the right practices and policy-making for the realisation of the 2030 Sustainable Development Goals three, six, eleven, twelve, thirteen, fourteen, and fifteen (3, 6,11,12,13,14, and 15) agendas by the world leaders which is focused on attaining good health and well-being; clean water, environment, and sanitation; sustaining cities and communities from degradation; responsible consumption and production; preserving the climate from the plastic-induced release of greenhouse gases thus reducing the number of deaths; protection of seas and oceans; wildlife extinction; and repairing the ecosystems and biodiversity from destruction. Hence, proper plastic pollution and waste management should be encouraged by the government and established authorities to tackle the adverse health effects of plastic leachates on humans, marine, and soil and also enable the control of the hazardous chemicals leached and transported by plastics that have undermined the health of man and other organisms.
Materials having high hardness and difficult to cut are becoming more popular in distinct industries such as automobile, aerospace, medical, construction, nuclear, sports and others. Because, hard and difficult to cut materials offered high strength to weight ratio, high resistance against wear, high yield strength, high resistance against corrosion, and ability to retain high strength at elevated temperature. However, the machining of hard and difficult to cut material poses a serious challenge owing to severe tool wear and higher cutting force involved. To overcome this, Laser assisted machining (LAM) has shown to be one of the most promising technologies for cutting difficult-to-cut materials. Hence, the aim of current review paper is to provide an overview on LAM, historical background, basic phenomena of laser generation, properties of lasers, generalized concept of laser- material interaction, types of lasers, distinct modes of laser operations and applications. Finally, the recent advances in laser assisted machining are discussed.
Ocean acidification (OA) and microplastics (MPs) contamination are two results of human excises. In regions like estuarine areas, OA and MPs exposure are happening at the same time. The current research investigated the synthesized effects of OA and MPs exposure for a medium-term duration on the physiology and energy budget of the thick shell mussel Mytilus coruscus. Mussels were treated by six combinations of three MPs levels (0, 10 and 1000 items L-1) × two pH levels (7.3, 8.1) for 21 d. As a result, under pH 7.3, clearance rate (CR), food absorption efficiency (AE), respiration rate (RR), and scope for growth (SFG) significantly decreased, while the fecal organic dry weight ratio (E) significantly increased. 1000 items L-1 MPs led to decrease of CR, E, SFG and increase of AE under pH 8.1. Interactive effects from combination of pH and MPs were found in terms of CR, AE, E and RR, but not for SFG of M. coruscus.
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Plastic pollution is generated by the unsustainable use and disposal of plastic products in modern society, threatening economies, ecosystems, and human health. Current clean-up strategies have attempted to mitigate the negative effects of plastic pollution but are unable to compete with increasing quantities of plastic entering the environment. Thus, reducing inputs of plastic to the environment must be prioritized through a global multidisciplinary approach. Mismanaged waste is a major land-based source of plastic pollution that can be reduced through improvements in the life-cycle of plastics, especially in production, consumption, and disposal, through an Integrated Waste Management System. In this review paper, we discuss current practices to improve life cycle and waste management of plastics that can be implemented to reduce health and environmental impacts of plastics and reduce plastics pollution. Ten recommendations for stakeholders to reduce plastic pollution include (1) regulation of production and consumption; (2) eco-design; (3) increasing the demand for recycled plastics; (4) reducing the use of plastics; (5) use of renewable energy for recycling; (6) extended producer responsibility over waste; (7) improvements in waste collection systems; (8) prioritization of recycling; (9) use of bio-based and biodegradable plastics; and (10) improvement in recyclability of e-waste.
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The analysis, prevention, and removal of microplastics (MPs) pollution in water is identified as one major problem the world is currently facing. MPs can be directly released to water or formed by the degradation of bigger plastics. Nowadays, it is estimated that annually between 4 and 12 million tonnes of plastic go into the seas and oceans-with a forecast for them to outweigh the amount of fish in 2050. Based on the existing studies, the characterization of MPs in waters is still one of the remaining challenges because they can be easily confused with organic or other types of matter. Consequently, there is an urgent necessity to establish pathways for the chemical identification of the MP nature. In this perspective, the recent techniques and instrumentation for MP characterization (Raman and Fourier-transform infrared spectroscopies and microscopies, pyrolysis and thermal desorption gas chromatography, imaging techniques, etc.) are discussed including considerations to the multidimensionality of the problem. This perspective also summarizes and provides updated data on the sources and occurrence, transport and fate of MPs in aquatic ecosystems, as well as influencing conditions and factors affecting dispersal. Additionally, how engineering and biotechnological tools, such as advanced water treatments, would help to control, reduce, or even eliminate MP pollution in the near future is outlined.
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Single-use plastics, or SUPs (plastic bags, microbeads, cutlery, straws and polystyrene) are substantial sources of plastic marine pollution, yet preventable via legislative and non-legislative interventions. Various international legislative strategies have been reported to address plastic marine pollution from plastic bags and microbeads, but these have since been accompanied by recent increasing public awareness triggered by international agencies and organizations. The Sixth International Marine Debris Conference highlighted increasing intervention strategies to mitigate SUP pollution. This study presents new multi-jurisdictional legislative interventions to reduce SUPs since 2017 and incorporates emergence of new non-legislative interventions to mitigate other types of SUPs at individual and private-sector levels that complement or influence legislative interventions. Further, effectiveness of SUP bag interventions (e.g., bans vs. levies) to help reduce SUP marine pollution are presented and range between 33-96% reduction in bag use.
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Di-2-ethylhexyl phthalate (DEHP) is extensively used as a plasticizer in many products, especially medical devices, furniture materials, cosmetics, and personal care products. DEHP is noncovalently bound to plastics, and therefore, it will leach out of these products after repeated use, heating, and/or cleaning of the products. Due to the overuse of DEHP in many products, it enters and pollutes the environment through release from industrial settings and plastic waste disposal sites. DEHP can enter the body through inhalation, ingestion, and dermal contact on a daily basis, which has raised some concerns about its safety and its potential effects on human health. The main aim of this review is to give an overview of the endocrine, testicular, ovarian, neural, hepatotoxic, and cardiotoxic effects of DEHP on animal models and humans in vitro and in vivo .
Single-use plastics (SUPs), invented for the modern “throwaway society,” are intended to be used only once. They are being increasingly produced and used globally, most notably as packaging or consumables, such as SUP shopping bags or disposable tableware. We discuss how most SUPs are landfilled or incinerated, which causes pollution, consumes valuable land, and squanders limited natural resources. Only relatively small amounts are currently recycled, a hindrance to the concept of a circular economy. Moreover, SUP litter aggregation in the natural environment is a major concern. This article briefly reviews SUP contamination in various environmental media including soil, rivers, lakes and oceans around the world. In the face of mounting evidence regarding the threat posed to plant growth, soil invertebrates and other land animals, (sea) birds, and marine ecosystems, there is a growing push to minimize SUPs. Regulatory tools and voluntary actions to reduce SUP usage have been put forward, with some suggestions for minimizing SUP waste.
Capsule: The concentration, distribution sources and fate of microplastics in the global marine environment were discussed, so also was the impact of microplastics on a wide range of marine biota.
Plastic pollution and its environmental effects has received global attention the recent years. However, limited attention has so far been directed towards how plastics are regulated in a life cycle perspective and how regulatory gaps can be addressed in order to limit and prevent environmental exposure and hazards of macro- and microplastics. In this paper, we map European regulation taking outset in the life cycle perspective of plastic carrier bags: from plastic bag production to when it enters the environment. Relevant regulatory frameworks, directives and authorities along the life cycle are identified and their role in regulation of plastics is discussed. Most important regulations were identified as: the EU chemical Regulation, the Packaging and Packaging Waste Directive including the amending Directive regarding regulation of the consumption of lightweight plastic carrier bags, the Waste Framework Directive and the Directive on the Landfill of Waste. The main gaps identified relate to lack of clear definitions of categories of polymers, unambitious recycling rates and lack of consideration of macro- and microplastics in key pieces of legislation. We recommend that polymers are categorized according to whether they are polymers with the same monomer constituents (homopolymers) or with different monomer constituents (copolymers) and that polymers are no longer exempt from registration and evaluation under REACH. Plastics should furthermore have the same high level of monitoring and reporting requirements as hazardous waste involving stricter requirements to labelling, recordkeeping, monitoring and control over the whole lifecycle. Finally, we recommend that more ambitious recycle and recovery targets are set across the EU. Regulation of the consumption of lightweight plastic carrier bags should also apply to heavyweight plastic carrier bags. Last, the Marine and Water Framework Directives should specifically address plastic waste affecting water quality.
Municipal effluent discharged from wastewater treatment works (WwTW) is suspected to be a significant contributor of microplastics (MP) to the environment as many personal care products contain plastic microbeads. A secondary WwTW (population equivalent 650 000) was sampled for microplastics at different stages of the treatment process to ascertain at what stage in the treatment process the MP are being removed. The influent contained on average 15.70 (±5.23) MP·L–1. This was reduced to 0.25 (±0.04) MP·L–1 in the final effluent, a decrease of 98.41%. Despite this large reduction we calculate that this WwTW is releasing 65 million microplastics into the receiving water every day. A significant proportion of the microplastic accumulated in and was removed during the grease removal stage (19.67 (±4.51) MP/2.5 g), it was only in the grease that the much publicised microbeads were found. This study shows that despite the efficient removal rates of MP achieved by this modern treatment plant when dealing with such a large volume of effluent even a modest amount of microplastics being released per liter of effluent could result in significant amounts of microplastics entering the environment. This is the first study to describe in detail the fate of microplastics during the wastewater treatment process.