industry and environment - DTIE

Chemicals management
substances with production volumes
of 10 tonnes or more, and
these data are also needed for classification
of aquatic toxicity. The
REACH system specifies criteria
for classifying substances as PBT
(persistent, bioaccumulating and
toxic) and as vPvB (very persistent
and very bioaccumulating). However,
it is only for substances with
production volumes of 100
tonnes or more that the required
data are sufficient for applying the
PBT and vPvB criteria.
In summary, with the implementation of
REACH, data requirements for “existing” chemicals
will increase while the requirements for
“new” chemicals are reduced. Existing substances
represent about 99% of production volume,
which means the total effect is in the direction of
an improved knowledge base for risk assessment.
However, that improvement is not sufficient to
provide the information required for classification
and authorization decisions.
For substances with production volumes of 10
tonnes or more, the required information is not
enough to apply any of the classification or authorization
criteria under consideration here (i.e.
acute mammalian toxicity, acute aquatic toxicity,
skin irritation, eye irritation, skin sensitization,
carcinogenicity, reproductive toxicity, PBT or
vPvB). Only for substances with production volumes
of 100 tonnes or more is the required information
sufficient to potentially trigger the
REACH authorization process. For none of the
substances regulated by REACH will the required
information be sufficient to classify for carcinogenicity.
Risk management
measures, including
question-mark labelling
Risk management
Risk assessment
vPvB
PB
non-PB
Long-term
aquatic
toxicity
All new and
existing
substances
Figure 6
Outline of the proposed new system
P and B
data
vPvB
PB
non-PB
Improved priority-setting
As we have already seen, in REACH (as well as in
current regulations) production volume determines
test requirements. The higher a particular
substance’s production volume, the more extensive
is the required test battery. The rationale for
using production volume as a priority-setting tool
is the assumption that higher production volume
is associated with higher potential for exposure,
and therefore with higher risk of adverse effects.
This is a sensible argument, but the connection
between total production volume and risk is indirect
and not at all certain.
There are at least three problems with using
production volume to determine test requirements.
First, due to lack of research in this area,
the extent to which production volume predicts
exposure is essentially unknown. Secondly, a positive
correlation between production volume and
exposure does not necessarily lead to an equally
strong positive correlation between production
volume and risk. Risk depends on a combination
of exposure and toxicity. Substances with low toxicity
may be over-represented among high-volume
substances (Cunningham and Rosenkranz 2001).
Thirdly, even if total exposure to a low-volume
substance is low, individual exposures may be
high, e.g. in the workplace.
In our view, the role of production volume as a
priority-setting criterion for data acquisition
should be gradually reduced. Instead, we propose
three other mechanisms for priority-setting:
Figure 7
Proposed tiered test strategy for PB compounds
Restrictions Restrictions Restrictions
+
Reproductive
-
and
developmental +
toxicity
-
Chronic
toxicity and
carcinogenicity
+
-
Risk
management
decision
Prohibition
Long-term and
reproductive
toxicity testing
Tiered testing
1. Chemical properties of the substance
Substances with different chemical characteristics
will have a different fate and behaviour in the
environment (e.g. partitioning, persistency, ability
to bioaccumulate). They will also
require different approaches to testing
(e.g. due to their lipophilicity)
and will differ in their propensity to
potentially adverse reactions with
biological material (reactivity).
Chemical characterization with
regard to reactivities, persistency
and bioaccumulative potential can
thus be used both for priority-setting
and to improve testing strategies.
2. Results from lower tier testing
Use of tiered testing should be strengthened, so
that certain results in a lower tier test automatically
lead to requirements for further testing. For
example, substances that are acutely toxic to
Daphnia should be tested for short-term effects in
fish and algae; in case of positive findings in these
tests, long-term testing in aquatic species should
also be performed.
3. Incentives for voluntary testing
Mechanisms should be created to give producers
incentives to test particular low-volume substances
more extensively than the minimum
requirements.
An amended system of testing
requirements
In the amended system that we propose, all substances
are subjected to an initial chemical characterization
with regard to their reactivities and
their persistency and bioaccumulative properties.
Based on these data, substances should be classified
as either:
1. very persistent and very bioaccumulating
(vPvB);
2. persistent and bioaccumulating (PB); or
3. having low persistence and potential for bioaccumulation
(non-PB).
Criteria for such a classification are
already available in the current REACH
proposal.
Substances that are both persistent and bioaccumulating
can give rise to toxic effects after a
greater time and at a greater distance than other
chemicals. Long-term exposures and exposure of
unborn and newborn children to these substances
can be anticipated. Previous experience has shown
that vPvB substances should not be used. We propose
that use of substances with these properties
should in principle be prohibited. This is stricter
than the authorization process currently proposed
in REACH (Figure 6).
For PB substances, we propose a tiered test system
starting with a long-term test for aquatic toxicity.
If this is negative, a reproductive and
developmental study in mammals is required; if it
turns out negative, a chronic toxicity and carcinogenicity
study is mandatory. Use of PB substances
classified for any of these toxicological effects (i.e.
toxic PB substances) should be restricted and, if
at all allowed, accompanied by appropriate precautionary
measures including emission control
UNEP Industry and Environment April – September 2004 ◆ 15