News
Health & Safety Update (December 2009)
Chemical Safety Assessment in a Nutshell - do you understand
your REACH responsibilities?
If you have REACH responsibilities and are blundering in the
dark then there is a light at the end of the tunnel. The European
Chemicals Agency is producing a set of simplified versions of
Registration, Evaluation, Authorisation and Restriction of
Chemicals (REACH) guidance documents, with the aim of making the
guidance more accessible and understandable.
REACH is based on the principle that the onus is on industry to
ensure that the substances it manufacturers and places on the
market have no adverse effects on human health and the
environment.
This document, one of the publications in the new 'Guidance in a
Nutshell' series, attempts to explain, in simple terms, the
principal issues associated with the Chemical Safety Assessment
(CSA) required under REACH.
The guide covers:
- what CSAs are;
- when such an assessment is required;
- the preparation needed for CSAs;
- the time and level of expertise required;
- the importance of communicating information throughout the
supply chain.
A brief outline is given below:
CSAs
The CSA process is intended to identify the conditions under
which the manufacture and use of a substance is regarded as being
safe. It consists of three main elements:
- hazard assessment – evaluation of the available relevant
information on a given substance, eg its intrinsic properties, its
manufacture and use, and related emissions and exposures. The aim
is to identify the hazards associated with the substance, their
potential effects on human health and the environment, and (where
possible) determine safe thresholds for exposure.
- exposure assessment – measuring or estimating the dosages of
the substance to which humans or the environment are or maybe
exposed. These 'exposure scenarios' will cover all the identified
uses and life stages of a substance.
- risk characterisation – compares the levels of exposure with
the threshold levels for each effect. Under REACH, risks are
regarded as being controlled where a substance's exposure levels
are below the threshold levels for humans and the environment.
Where there are no threshold levels, emissions and exposures have
to be minimised or eliminated for the risks to be regarded as
controlled.
Once the risks are under control, the assessment ends. Where
this is not the case, the assessment has to be refined, either by
gathering more information on the substance, or changing the
conditions under which it is manufactured or used, or by making
more precise estimations of exposure. Assessment is an iterative
process which continues until the risks can be shown to be under
control.
The conditions under which the risks are under control are known
as the final exposure scenario.
When Are CSAs required?
CSAs must be undertaken for all substances subject to REACH
registration in quantities of ten tonnes or more per year, per
registrant. There are exceptions, namely where the substance is
present in a preparation in quantities below certain threshold
limits, and for intermediates manufactured and used in accordance
with strictly controlled conditions.
Normally, the obligation to carry out an assessment and document
it as part of the Chemical Safety Report (CSR) rests with the
substance manufacturer or importer, but there may be situations
where downstream users have to make their own assessments.
How to Prepare an Assessment
Assessments should include:
- an assessment of any hazards presented by the substance;
- identification of the exposure scenarios, that is the
conditions under which the risks arising from the substance's
manufacture and use are regarded as controlled;
- documentation of the relevant data and information in the
CSR;
- implementation of the conditions of use and manufacture
intended to control the risks;
- communication of the conditions of use down the supply
chain.
The actual assessment process consists of the following
steps:
- gathering and evaluating information;
- identifying the hazards;
- classification and labelling;
- threshold level derivations;
- PBT and vPvB assessment. (persistent bioaccumulative and toxic
and very persistent very bioaccumulative).
Classification and Labelling
The criteria under which substances and preparations can be
classed as dangerous are set out in Directive 65/548/EEC and
Directive 1999/45/EC. Classification of a substance as dangerous is
a critical input in the assessment process.
Derivation of Threshold Levels
Where possible, the registrant will define the threshold levels
for exposure below which, the risks to the environment and human
health can be regarded as being controlled. The Derived No Effect
Level (DNEL) represents the threshold above which humans should not
be exposed, while the Predicted No Effect Concentration (PNEC)
represents the concentration of the substance in any environment
below which, adverse effects would be unlikely to occur through
short-term or long-term exposure.
PBT and vPvB assessment
The PBT and vPvB assessment addresses concerns over a
substance's ability to persist and bio-accumulate in the
environment, as well as its toxic effects. This is required for all
substances for which a CSA has to be conducted.
Communication within the Supply Chain
It is important that manufacturers and importers consider all
identified uses of a substance in their CSR. In particular, it is
vital that relevant information in the CSRs is communicated to
downstream users of the substance so as to ensure its safe use.
This is done through the safety data sheet and the exposure
scenarios attached to it.
Downstream users must also communicate up the supply chain if
they discover any new information on a substance's hazardous
properties or any other matter that might compromise the risk
management measures identified in the safety data sheet. Where a
downstream user decides to carry out his own assessment for any use
not covered by the registrant's assessment, he assumes
responsibility for defining and communicating the safe conditions
of use.
See http://guidance.echa.europa.eu/guidance2_en.htm
or contact the advice line or your dedicated consultant for more
information.