ISO/TS 21623:2017

TECHNICAL ISO/TS
SPECIFICATION 21623
First edition
2017-11
Workplace exposure — Assessment
of dermal exposure to nano-
objects and their aggregates and
agglomerates (NOAA)
Exposition sur les lieux de travail — Évaluation de l'exposition
cutanée aux nano-objets et à leurs agrégats et agglomérats (NOAA)
Reference number
©
ISO 2017
© ISO 2017, Published in Switzerland
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ii © ISO 2017 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Dermal exposure to NOAA — Evidence and exposure routes . 4
4.1 General . 4
4.2 Source domains . 4
4.3 Exposure routes . 5
5 Stepwise approach for assessment of dermal exposure to NOAA . 6
5.1 General . 6
5.2 Step 1: Desk evaluation . 7
5.2.1 Step 1A: Evaluation of toxicological hazard based on NOAA composition . 7
5.2.2 Step 1B: Screening for potential risks associated with dermal exposure to
insoluble (non-flexible) NOAA . 8
5.2.3 Step 1C: Screening for potential risks associated with dermal exposure
based on job title . .10
5.3 Step 2: Observation of potential for dermal exposure .11
5.4 Step 3: Additional observation of worker behaviour.11
5.5 Step 4: Quantification of NOAA .11
5.6 Step 5: Evaluation and review .12
Annex A (informative) Industries associated with use of nanomaterials or nano-
enabled products .13
Annex B (informative) How to determine skin disruption? .16
Annex C (informative) DeRmal Exposure Assessment Method (DREAM) .18
Annex D (informative) Inadvertent ingestion exposure .24
Annex E (informative) Exploring dermal exposure measurements of nanoparticles .27
Bibliography .31
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
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ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
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on the ISO list of patent declarations received (see www.iso.org/patents).
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URL: www.iso.org/iso/foreword.html.
ISO/TS 21623 was prepared by the European Committee for Standardization (CEN) Technical Committee
CEN/TC 137, Assessment of workplace exposure to chemical and biological agents, in collaboration with
ISO Technical Committee ISO/TC 146, Air quality, Subcommittee SC 2, Workplaces atmospheres, in
accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
iv © ISO 2017 – All rights reserved

Introduction
Dermal exposure assessment explores the dynamic interaction between environmental contaminants
and the skin. In contrast to inhalation exposure assessment, the assessment of dermal exposure
requires a different set of exposure considerations. During the last decades, the body of knowledge with
regard to dermal exposure has expanded for many types of substances, which amongst others resulted
in publications for the evaluation of dermal exposure to chemical substances that can be found, for
example, in CEN/TR 15278, CEN/TS 15279, and ISO/TR 14294.
Currently, engineered/manufactured nanomaterials and nano-enabled products are produced and
used on a wide scale. Occupational skin exposure to these substances can have biological relevance
to human health. Potential adverse effects include local skin effects, systemic toxicity following skin
absorption/uptake and inadvertent ingestion through the hand-to-mouth pathway. This document
provides guidance for the evaluation of potential dermal exposure to manufactured nano-objects, their
agglomerates and aggregates (NOAA).
This document is a compilation of the results of a pre-normative research project, executed under
Mandate M/461 for standardization activities regarding nanotechnologies and nanomaterials as issued
by the European Commission. This pre-normative research gives an overview of the mechanisms of
occupational dermal exposure to nanoparticles or nano-enabled products. This includes potential
concomitant for intake or uptake. It is based on relevant evidence of exposure for identified job
titles. Part of the pre-normative research comprised experimental work on the skin penetration
of nanoparticles, transfer of nanoparticles from a surface to the skin, and exploratory work on the
[4]-[6]
feasibility to quantify dermal exposure to NOAA .
TECHNICAL SPECIFICATION ISO/TS 21623:2017(E)
Workplace exposure — Assessment of dermal exposure to
nano-objects and their aggregates and agglomerates (NOAA)
1 Scope
This document describes a systematic approach to assess potential occupational risks related to
nano-objects and their agglomerates and aggregates (NOAA) arising from the production and use of
nanomaterials and/or nano-enabled products. This approach provides guidance to identify exposure
routes, exposed body parts and potential consequences of exposure with respect to skin uptake, local
effects and inadvertent ingestion.
This document also considers occupational use of products containing NOAA by professionals, e.g.
beauticians applying personal care products, cosmetics or pharmaceuticals, but does not apply to
deliberate or prescribed exposure to these products by consumers.
This document is aimed at occupational hygienists, researchers and other safety professionals to assist
recognition of potential dermal exposure and its potential consequences.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 1540, Workplace exposure — Terminology
ISO 18158, Workplace air — Terminology
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 1540, ISO 18158 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
agglomerate
collection of weakly or medium strongly bound particles where the resulting external surface area is
similar to the sum of the surface areas of the individual components
Note 1 to entry: The forces holding an agglomerate together are weak forces, for example, van der Waals forces or
simple physical entanglement.
Note 2 to entry: Agglomerates are also termed secondary particles and the original source particles are termed
primary particles.
[SOURCE: ISO/TS 80004-2:2015, 3.4]
3.2
aggregate
particle comprising strongly bonded or fused particles where the resulting external surface area is
significantly smaller than the sum of surface areas of the individual components
Note 1 to entry: The forces holding an aggregate together are strong forces, for example, covalent or ionic bonds
or those resulting from sintering or complex physical entanglement, or otherwise combined former primary
particles.
Note 2 to entry: Aggregates are also termed secondary particles and the original source particles are termed
primary particles.
[SOURCE: ISO/TS 80004-2:2015, 3.5]
3.3
dermal contact volume
volume containing the mass of the agent that contacts the dermal exposure surface (3.7)
Note 1 to entry: This is equivalent to the volume of the skin contaminant layer and for practical reasons
represents the volume of the compartment where the mass of the substance is all contained.
[SOURCE: CEN/TR 15278:2006, 2.2, modified — Note 1 adapted]
3.4
dermal exposure concentration
dermal exposure mass (3.6) divided by the dermal contact volume (3.3) or the dermal exposure mass
divided by the mass contained in the skin contaminant layer
Note 1 to entry: Dermal exposure concentration is expressed in g/l or g/kg or other appropriate units as
necessary.
[SOURCE: CEN/TR 15278:2006, 2.4, modified — Note 1 adapted]
3.5
dermal exposure loading
dermal exposure mass (3.6) divided by the dermal exposure surface (3.7) area
Note 1 to entry: For practical reasons, it can be expressed as mass of agent in an exposed part of the skin
contaminant layer divided by the surface area of that part.
[SOURCE: CEN/TR 15278:2006, 2.5]
3.6
dermal exposure mass
mass of agent present in the dermal contact volume (3.3)
Note 1 to entry: For practical reasons, it is defined by the amount of agent in g present in the skin contaminant
layer, or other appropriate units as necessary.
Note 2 to entry: The outcome of the process of dermal exposure, i.e. the contact, can be expressed by different
parameters of exposure.
[SOURCE: CEN/TR 15278:2006, 2.6, modified — Note 1 adapted]
3.7
dermal exposure surface
skin sur
...