**2.1 Primary microplastics**

Plastic ranging between size of 1 μm and 5 mm are considered primary microplastics. Microplastics are affixed to certain products due to their discrete functions. They are also operated as mordant in cosmetics and soap products and also act as conveyor of pigments. Plastic powder, granulates, pellets are some examples of primary microplastics [1, 20]. Primary microplastics are also used as exfoliates. They are the main protagonist of several day to day products like hand cleaners, toothpastes, face washes [20]. Primary microplastics are also used in dental polishes. If they are not discarded in the efficient way possible, they end up blemishing the environment. Primary microplastics also possess diverse industrial implementations like for gas and oil analysis they are required as drilling fluids, for cleaning metal surfaces to eliminate the paint, rinsing of engines etc. [21–23]. Microplastics like polystyrene, acrylic, polyester are used in industries [24].

### **2.2 Secondary microplastics**

Repudiated plastic bags or fishing nets, household items and discarded plastics undergo weathering and photo degradation process and get transfigured into smaller plastic particles, thus constituting secondary microplastics. Abrasion of plastics is manifested by UV light at soil surface and by ocean waves. Secondary microplastics are also fabricated by washing machines [24, 25]. It also includes fragments of textile fiber originated from synthetic fibers, and released during the laundering process [26]. The root sources of secondary microplastics are discarded plastic debris from household items and industrial products. Secondary

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*Sources, Fate, and Impact of Microplastics in Aquatic Environment*

microplastics are considered to be the most dominating microplastics [27, 28]. Their copiousness in water bodies increases with elevating discharge of plastic debris and its continuous transformation into secondary microplastics. Textile industry products, tires, decorative paints all contribute to the genesis of secondary

According to Leslie [29] plastic microbeads are utilized as additives in countless cosmetics and personal care products. They act as sorbent as well as exfoliators. Plastic microbeads are incorporated in several cosmetic products such as 350,000 plastic particles were observed in a facial scrub tube in USA [20]. A study from USA also evaluated the presence of 1700-6400 particles of plastic per g in toothpaste [1]. According to Strand [30] toothpaste contains 0.1-0.4% microbeads in accordance with weight, facial scrubs contain around 1.6-3.0%. Facial scrub possesses 0.9-4.2%, exfoliating scrub contains 10.6% and shower gel around 0.5-3.0%. One of the plastic types that are frequently perceived in microplastics is polyethylene (PE). In European country PE plastic microbeads were considered most dominating, with around 4073

For cleansing surfaces primary microplastics are used as abrasive. Plastic such as polyester, polycarbonate, polyamide is used in blast media. Main purpose of blasting abrasives is in cleansing of rims, removal of paints and cleansing of ships. These abrasives are also used in marine industries for cleaning the tanks. Blasting is done in different cabins, closed or semi-closed. Area must be encrusted properly. Emission rate are quite high if done in open premises. Turbines blades are cleansed by this process; this leads to release of primary microplastics in aquatic environment. Microplastics are even used in maintenance and cleaning products as abrasive material. To remove grease, paints, oil from hands primary

Browne et al. [25] assorted that process of laundries in household and industries leads to mass production of primary microplastics via scraping and dispersion of fibers, which was then emitted out in sewage water and culminates in the ocean [31]. Tyres contain profuse mixture of several synthetic polymers in addition with natural rubber. Tyres get deteriorated when used and tyre dust that contains synthetic rubber circulated by wind or swiped away by rain. Large segments of such

Primary microplastics are appended to paint and preservative. This gives matting effect and acts as color amplifier. This improves longevity of wood, provides hardened and abrasion resistance. It is also used to diminish the density of paints [20]. A study done by Poulsen et al. [32] stated that 8-30% of waste generation is triggered by paint spillage and other paint jobs. Approximately 65-97% of waste culminates as solid

*DOI: http://dx.doi.org/10.5772/intechopen.93805*

**3.2 Blasting abrasives and cleaning products**

particles were reported to congregate in the sea [19, 23].

microplastics [20].

tons usage.

**3. Sources of microplastics**

**3.1 Personal care products**

microplastics are used [20].

**3.3 Synthetic textile and tyres**

**3.4 Paint and wood preservatives**

microplastics are considered to be the most dominating microplastics [27, 28]. Their copiousness in water bodies increases with elevating discharge of plastic debris and its continuous transformation into secondary microplastics. Textile industry products, tires, decorative paints all contribute to the genesis of secondary microplastics [20].
