Methods for the collection and characterization of airborne particles in
the textile industry
Authors: Visileanu Emilia , Catalin Grosu Marian , Tiberiu Miclea Paul , Altmann Korinna , Brossell Dirk 
Published: July 2023

Airborne particulate matter is one of the main air pollutants. Their
impact on mortality, and the occurrence of pulmonary and cardiovascular
complications, have been the subject of numerous studies. Airborne particles
are complex mixtures of organic and inorganic substances from different
sources of particle emissions. Particulate Matter (PM) particles are
classified according to their aerodynamic diameter expressed in µm and can
vary from coarse (PM 10) to fine (less than PM 2.5). These diameter
considerations are fundamental because they condition the penetration of
particles into the bronchopulmonary system and the body. In recent years,
there has been an interest in so-called “ultra-fine” particles, with a
diameter of 0.1 µm (or 100 nm), or PM 0.1. They are nanoparticles and their
impact on human health is not yet clear.With more than 1.5 million
employees, textiles and clothing is a diverse sector that plays an important
role in the European manufacturing industry, producing a turnover of €162
billion.An important component of the solid particles that generate air
pollution in the textile industry is microplastics (MP) and nano plastics
(NP), which also include microfibers (<5mm) and nanofibers (<100
nm), respectively. The particles released into the air during fiber and yarn
processing range from 1 µg/m3 to 50 µg/m3.The paper presents the results of
the determination of indoor and outdoor air concentration levels in textile
companies, to identify the areas with the highest concentration level, by
using an online recording system such as the Laser Aerosol Spectrometer MINI
LAS model 11-E. The total concentration level TSP (µg/m3), the fractions PM
10(µg/m3), PM 2.5(µg/m3), PM1(µg/m3), as well as the total number of
particles TC (1/l), were shown. It was noted that TSP is approximately at
the same level both indoors and outdoors, but the fractions of PM10, PM2.5,
and PM1 have much higher values indoors than outdoors with possible
consequences on workers' health.The next step was the collection of fibers,
namely micro and nano plastic particles from the vicinity of the workplaces
of polyester, polyamide, and polypropylene fibers processing units in the
textile industry in Romania, to obtain a sufficient quantity for laboratory
analysis to determine the size and shape of the particles as well as their
chemical composition. Two types of pumps were used, differentiated by their
operating parameters: TECORA SKYPOST with airflow of 38 l/min and GILAIRPLUS
with airflow 2l/min. Filters made of different materials with different
diameters and pore sizes were used, namely: quartz filters (ø 47 mm, and ø
37 mm) on a TECORA SKYPOST type pump, polycarbonate nucleopore coated with a
gold membrane (ø 25 mm) and silica filter (ø 9 mm) on GILAIRPLUS type
pump.Using descriptive statistics, the calculation of correlation
coefficients highlighted a strong correlation between the variables:
"Collected mass/ Air concentration" and "Collected mass/ Air volume" for all
diameters of the filters.The highest collected particle volume, determined
by weighing the filters before and after collection, was obtained with the
quartz filters (ø 47 mm) at an airflow of 38 l/min. The particles collected
(polyester, polyamide, polypropylene) in the first stage were analyzed by
SEM and thermogravimetric and it was found that the quartz filters absorbed
the particles inside, with very few remaining on the surface. Thus no known
methods can be used to perform analysis for particles collected on quartz
filters. The number of particles on the filters was insufficient for
analysis either because of the collection parameters used or because of the
loss of particles during transport. As a result, in the next step, the use
of 9 mm Si filters using the GILAIRPLUS pump at an airflow rate of 2l/min
was chosen.To improve the transport conditions and avoid the loss of the
particles and keep them on the surface of the filters, two methods were
applied:- after weighing the filters were reintroduced into the collection
pump holder;- a filtration system for airborne micro-nano plastics was
designed and manufactured to selectively collect and transport PM10 and PM1
particles collected on SI filters.In both cases, SEM, Raman mapping, and
GS-MS microscopy were used for analysis.Several times more PM10 than PM1
(74.5µg compared to 12.5 µg) was found. In all cases, both particles and
fibers showed the same Raman fingerprint.The GS-MS analyses showed some
contamination of the workspaces with particles other than the processed
fibers. The presence of non-notifiable substances was also observed.The most
viable filters are Si filters with a pore size of 10 microns to 1 micron and
the use of the selected collection and transport filter system. In the
following a filter system will be applied for collection on Au
membrane-coated polycarbonate filters.