Book Review

“Synthetic Nano- and Microfibers”, edited by R. Martijn Wagterveld, Jan C.M. Marijnissen, Leon Gradon and Arkadiusz Moskal

WETSUS, 2020, 256 p. ISBN: 978-1-71663-242-6, DOI:10.20850/9781716632426

The book can be downloaded for free: https://osf.io/487wv/download

Global production of fibrous material is significantly growing with expectation of reaching 145 million metric tons in 2030. Production includes mostly synthetic polymers fibers, cotton fibers and man-made cellulosic (viscose) fibers. A smaller contribution comes from animal-made fibers (wool, silk). The main uses of fibrous material are in clothing, household and furnishing, industrial construction, automotive and other.

Increasing consumption of fabric material causes the accumulation of single fibers into the natural environment. Significant numbers of fibers are discharged into wastewater from washing clothes, deposition from atmosphere or by other ways of transport. Fibers are now the most prevalent type of anthropogenic particles found by microplastic pollution surveys around the world. Substantial concentration of fibers has been detected in surface water, deep-sea and fresh water ecosystems. As a consequence, fibers are present in food, drinking water, human lungs and digestive tracts of aquatic animals. Currently, there is great concern for the release of plastic nano-and micro fibers and microparticles (microplastics) to the natural environment for which nobody knows, so far, the ultimate consequences for health and ecological homeostasis.

The potential risk introduced by the presence of fibers in the environment induces significant interests of researchers in this problem as becomes clear from an increasing number of publications related to microplastics. The aforementioned challenges were the source of inspiration for organization a workshop.

During November 4 and 5, 2019, a group of scientists from different parts in the world met at Wetsus, the European Centre of Excellence for Sustainable Water Technology in Leeuwarden the Netherlands, to discuss all known aspects of synthetic nano- and microfibers. This includes the morphology, physicochemical properties, production and origin of nano/micro fibers entering the atmosphere, water and food chain; the potential consequences of inhalation and ingestion for human health, and exposure and ingress via life cycle for aquatic biota; analytical and measurement methods; techniques to clean air and water, and protection means against inhalation or other ways to enter the human body. The group of top-experts from different disciplines, but all involved with small fibers, gathered to share their view from scientific, technical and health perspective, presented their subject of expertise, contributed to the discussion and made their contribution into a chapter for the book: “Synthetic Nano- and Microfibers”.

The chapters in this book have been placed in a logic sequence, starting with the statement of the problem, properties of small fibers, fibrous particle identification, via environmental and health issues, and ending with possible cleaning methods. It is very evident that still much is not known and that in each discipline more must be investigated. For almost each sub-research program reliable on-line measuring techniques are indispensable. We assume that this book presents the state of the art and will give directions on how to proceed to answer the many remaining questions. It is indisputable that it is essential to work together with all involved subdisciplines.

Table 1 Contents

Preface		xi
Day One
1	Plastic and the Planet: How to take care of the next generation By: Maria Westerbos	3
2	Micro- and nanofibers: aerodynamics and physicochemical aspect By: Arkadiusz Moskal, Tomasz R. Sosnowski	5
2.1	Introduction	5
2.2	Fiber dynamics in the viscous fluid	5
2.3	Modeling of the dynamics of fibrous particles in viscous fluid	11
2.4	Micro- and nanofibers on the air/liquid interface	12
2.5	Fibrous-like particles and lung fluids	14
2.6	Conclusions	16
3	Production of nano- and microfibers from synthetic and natural polymers - Nanofibers technology By: Michał Wojasiński, Tomasz Ciach	19
3.1	Introduction	19
3.2	Meltblowing	20
3.3	Electrospinning	21
3.4	Solution blow spinning	24
3.5	Centrifugal spinning	27
3.6	Conclusion	28
3.7	Acknowledgement	29
4	Questions and answers about synthetic fibers in wastewater treatment By: Heather A. Leslie, Edited by R. Martijn Wagterveld	35
5	Measurement of nano- and microfibers in water and air: Physical and chemical methods By: Louk Peffer, R. Martijn Wagterveld, Jan. C.M. Marijnissen	37
6	Measurement of nanofibers in the breathing air By: George Biskos, Jan C.M. Marijnissen	41
6.1	Introduction	41
6.2	Online physical characterization of nanofibers	42
6.2.1	Optical Sizing	42
6.2.2	Electrostatic Classification	43
6.2.3	The Fiber Aerosol Monitor	46
6.2.4	Aerodynamic classification	46
6.3	Integrated systems for determining the size and shape of aerosol nanoparticles	47
6.4	Online chemical analysis	49
6.5	Conclusions and future perspectives	50
7	A human risk banding scheme for high aspect-ratio materials By: Dirk Broßell, Asmus Meyer-Plath, Kerstin Kämpf, Sabine Plitzko, Wendel Wohlleben, Burkhard Stahlmecke, Martin Wiemann, Andrea Haase	55
7.1	Introduction	56
7.2	Risk banding and material properties required for HARM risk banding	57
7.2.1	Length	59
7.2.2	Respirability	61
7.2.3	Thickness (Rigidity)	61
7.2.4	Biopersistence	65
7.2.5	Release propensity (dustiness)	66
7.2.6	Dust agglomeration	67
7.2.7	WHO-fiber concentration	68
7.3	Summary of human risk banding for high aspect-ratio materials	71
7.4	Matrix for risk banding	71
7.5	Application in risk prediction for MWCNT	73
7.6	Conclusions and outlook	74
7.7	Acknowledgements	75
8	Deposition of synthetic fibers in human respiratory tract By: Yung Sung Cheng, Wei-Chung Su, Yue Zhou	81
8.1	Introduction	81
8.2	Materials and Methods	83
8.2.1	Human nasal airway cast	83
8.2.2	Human respiratory airway casts	83
8.2.3	Fiber materials	84
8.3	Experimental setup	88
8.4	Sample preparation, fiber counting and length measurement	90
8.5	Results and discussion	91
8.5.1	Fiber deposition efficiency in the human nasal airway	91
8.5.2	Comparison of nasal deposition between fibers and compact particles	93
8.5.3	Fiber Deposition in the Human Oral Airway	95
8.5.4	Fiber deposition in the tracheobronchial airways	98
8.5.5	Empirical model for fiber deposition in the nasal airway	100
8.5.6	Empirical model for fiber deposition in the oral airway	101
8.5.7	Empirical model for fiber deposition in the tracheobronchial airway	102
8.5.8	Fiber exposure index	103
8.6	Conclusions	104
Day Two
9	Micro and nanoplastics in the aquatic environment with special reference to synthetic fibers By: A. Dick Vethaak, C. Martínez-Gómez	111
9.1	Introduction	111
9.2	Sources, pathways and sinks	112
9.2.1	Major sources of MNPs	112
9.2.2	Sources of fibrous MNPs	113
9.2.3	Pathways and sinks	113
9.3	Composition of aquatic micro- and nanoplastic debris	113
9.3.1	Debris polymers	114
9.3.2	Chemical additives	114
9.3.3	Adsorption of chemical contaminants	114
9.3.4	Eco-corona, biofilm and biofouling	115
9.4	Factors that control degradation and fate of polymeric material	115
9.5	Physical and chemical quantification and characterization of MNPs	116
9.5.1	Analysis of microplastics in aquatic matrices	116
9.5.2	Analysis of microplastic fibers and nanoplastics	117
9.5.3	Uncertainties in aquatic MNP measurements	117
9.6	Occurrence of microplastics in aquatic systems	118
9.6.1	Microplastics in abiotic matrices	118
9.6.2	Microplastics in aquatic biota	119
9.7	Uptake and effects of MNPs on aquatic biota	122
9.7.1	Uptake	122
9.7.2	Physical effects	123
9.7.3	Chemical-mediated effects of MNPs	128
9.7.4	Microbial effects of MNPs	129
9.7.5	Potential ecological effects of MNPs	130
9.7.6	Field evidence and ecological relevance of laboratory studies	130
9.8	Key conclusions	130
9.9	Key knowledge gaps and research priorities	131
10	Micro(nano)plastics in aquatic organisms, transferability of knowledge from nanowires By: Martina G. Vijver, Willie Peijnenburg, Fazel Abdolahpur Monikh	147
10.1	Introduction	147
10.2	Aims of the chapter	148
10.3	Human exposure to micro(nano)plastics through food	148
10.4	Responses attributed to additives in micro(nano)plastics	149
10.5	Understanding responses attributed to MNPs in laboratory setting	149
10.6	Transferability of knowledge on nanowires to micro(nano)fibers	151
10.7	To summarize and recommend	153
11	Health effects of synthetic fibers and nanoparticles: Advanced electron microscopy to determine nanoparticle and nanoplastic in vivo By: Uschi M. Graham, Günter Oberdörster	157
11.1	Introduction	157
11.2	Background	158
11.3	Analytical imaging techniques for nanoparticles/fibers in tissues	159
11.4	Select case studies of nanoparticle-tissue interactions	164
11.5	Synopsis	171
12	The intake of synthetic fibers into the human body, by food, water and air By: Ingeborg M. Kooter, Heleen Lanters, Wilma Middel, Harrie Buist	175
12.1	Introduction	175
12.1.1	The origin of plastics	175
12.1.2	Plastics, blessing or curse	175
12.1.3	What are microplastics and microfibers	175
12.1.4	Are microplastics and synthetic microfibers a threat to human health?	176
12.1.5	Reading guide	177
12.2	Sources of synthetic microfibers	178
12.3	External exposure to synthetic microfibers	182
12.3.1	Introduction	182
12.3.2	Air	182
12.3.3	Water	183
12.4	Human exposure routes	187
12.4.1	Introduction	187
12.4.2	Inhalation pathway	187
12.4.3	Oral pathway	187
12.4.4	Dermal pathway	190
12.5	Internal exposure and human uptake routes	190
12.5.1	Introduction	190
12.5.2	Uptake via inhalation	191
12.5.3	Uptake via ingestion	193
12.5.4	Uptake via the skin	194
12.6	Conclusion	194
13	An overview of the effects of synthetic micro(nano)fibers following exposure, with a focus on humans By: Stephanie Wright	201
13.1	Introduction	201
13.2	Inferences from fiber toxicology	201
13.3	Plausible toxic properties of synthetic fibers	202
13.4	Occupational epidemiology of synthetic fibers	204
13.5	In vivo evidence	205
13.5.1	Mammalian models	205
13.5.2	Human studies	205
13.6	A potential for chemical effects?	206
13.7	Discussion	206
13.8	Conclusions, limitations and future work	207
14	Mechanics of fibrous particles immersed in selected flow conditions By: Rafał Przekop, Leon Gradoń	211
14.1	Introduction	211
14.2	Modelling of fibrous particle deposition in a fibrous filter	213
14.2.1	The effect of gas velocity and fiber orientation on deposition efficiency	214
14.2.2	The effect of particle volume and slenderness ratio on the deposition efficiency	215
14.2.3	Effect of collectors orientation	217
14.2.4	Flexible aggregate model	217
14.3	Lattice-Boltzmann modelling	220
14.4	Results and discussion	221
14.5	Conclusions	222
15	Cleaning water from nano- and microfibers By: R. Martijn Wagterveld, Inez J.T. Dinkla	227
15.1	Introduction	227
15.2	Nano- and microfibers in aquatic ecosystems	227
15.3	Techniques to remove nano- and microfibers	229
15.3.1	Separation at source	229
15.3.2	Waste water treatment plants	230
15.3.3	Alternatives to conventional treatment techniques	231
15.3.4	Approaches for nanofiber removal	234
15.4	Future perspective for waste water treatment	235
15.5	Conclusion	235
16	Workshop Summary and Conclusions By: Stephanie Wright, Uschi M. Graham, Arkadiusz Moskal	237
Index		241

Author’s Short Biography

•Jan C.M. Marijnissen

Jan C.M. Marijnissen is a former Associate Professor and Head of the Aerosol Laboratory at Delft University of Technology, the Netherlands, and a PERC visiting Professor at the University of Florida, USA. He is a visiting Professor at the University of Nairobi, Kenya. He has been an advisor for Wetsus, European Centre of Excellence for sustainable water technology in Leeuwarden, the Netherlands and is an advisor for the University of Applied Science in Leeuwarden, the Netherlands. Jan C.M. Marijnissen received a Master degree from Delft University of Technology and a Ph.D. degree in environmental engineering from the University of Minnesota, USA. He has more than 45 years of experience in the field of mine-ventilation and aerosol science and technology and is especially involved in the development of advanced aerosol measuring instrumentation, air cleaning methods and the production of particles via aerosol routes. He has (co)authored many articles, is co-editor of eight books on aerosols, and holds several patents. He is a member of several associations and a former president of the European Aerosol Assembly.