Statusvurdering vedr. afgivelse af organiske stoffer ... - Miljøstyrelsen

Denmark’s Technical University, DTU, has developed a new analytical method (HS-SPME-GC/MS)
for measurement of degradation products of antioxidants that is suitable for measurement of
degradation products of antioxidants in low concentrations (less than 1 µg /l).
Furthermore, DTU has a technique for measuring the NVOC with a detection limit of 45 µg/l, which
is a lower detection limit than those achieved under DS / EN 1484. DS / EN 1484 is a standard for
determination of total organic carbon (TOC) and dissolved organic carbon (DOC) used by the
testing laboratories.
A summary of recent studies shows that there are a number of substances that are found in
concentrations at the same level as the provisional health criteria (1 - 20 µg /l) derived by the
Danish EPA. The health assessment for the substances is however based on limited knowledge base,
and it is recommended that these substances be re-evaluated in terms of health impacts.
The status assessment has shown that there are a large number of substances that can be released
from the plastic pipes. Today, migration tests analyse only a small number of the substances relative
to the total release. However, development of procedures and analysis of all substances as well as
preparation of health assessment for each substance is a demanding task to undertake.
Furthermore, it is not certain that the substances found in the highest concentrations are the most
critical in relation to health. It is therefore recommended that a screening of the health risks for the
substances listed in Annex 2 of this status assessment be made. Subsequently, the analytical
program in the migration tests can be adjusted with the substances that are critical from a health
viewpoint.
The literature study shows that there is a basis for identifying the amount of migration agents which
a given pipe with a given composition of additives will release to the Danish users of drinking water
throughout the lifespan of the pipe. This can be achieved by application of the analytical methods
presented in this report, and by using the mathematical models described briefly in this report and
in detail in Denberg et al. /9/.
10 Statusvurdering vedr. afgivelse af organiske stoffer fra plastrør til drikkevand