**1.1 Overview of qualitative and quantitative identification methods**

In literature, different approaches for the determination of microplastics in aqueous matrices are reported [12]. They are chosen according to the data to be obtained and their usefulness. Mainly, several methods are used to acquire microplastic data such as color, size, shape, composition, and chemical concentration expressed in terms

**Figure 1.** *Source of microplastics from textiles sources.*

#### *Round Robin Test on Microplastic Counting and Identification Method DOI: http://dx.doi.org/10.5772/intechopen.109757*

of number, weight, or size per unit volume or area. However, in order to obtain reliable and reproducible results, it is necessary to eliminate all possible contaminants that may interfere with the acquisition of such data.

Usually, the analysis of microplastics, as suggested by some guidelines [13], requires several steps that mainly include 3 phases: sampling, sample preparation, and determination of the type of microplastic polymer. Sample preparation is preceded by purification treatments that can be chemical or physical and are used to obtain suspensions of microplastics with reduced presence of organic and inorganic contaminants. This approach acts as a bridge between sampling and detection of microplastics as its effects influence the analytical quality of the final data in relation to specific pretreatment conditions and volumes. The identification system is applicable to any type of sample containing microplastics. An appropriate analytical approach for the identification of microplastics is shown in **Figure 2**.
