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Cleaner Technology Projects in Denmark 1997
Environmental Aspects of PVC
Miljørapport nr. 313, 1997, Miljøstyrelsen
The recent years focus, on PVC and the substances’ environmental- and health risk
effects, has caused a need for clear and transparent information about the substance
through its entire life cycle. This report gives an account of a comprehensive Danish
study with important international contributions.
The aim of the project has been to bring about information on PVC and its
environmental- and health effects as a foundation for future evaluations and use of the
substance. Therefore, the report does not contain actual conclusions and recommendations.
In addition, the project group has chosen to only to a limited extent to incorporate
comparisons with other substances, instead they refer to other studies (here amongst
Environmental Project no. 131, 1995).
On the contrary, in this project great emphasis is put on the environmental- and health
effects of e.g. phthalate softeners and
new knowledge on these additives is included in the project. The evaluation of these
substances is therefore prioritised instead of a detailed account of the use of led- and
cadmium stabilisers, whose environmental effects are well known.
PVC is a thermo-plastic material that contains 57 % chlorine and 43
% hydrocarbon – measured in weight. In order to stabilise the material during the
production process heat stabilisers are added. Other additives are used to give the
material special properties depending on what it is going to be used for.
The primary raw materials are mineral oils, natural gas, and sodium chloride that are
converted to ethylene and chlorine and by syntheses to vinyl-chloride monomers (VCM). VCM
polymerises to PVC. PVC is not produced in Denmark. The total energy consumption is 66, 80
MJ/kg, including transport. 37,24 MJ/kg are used as fuel whilst 29,56 MJ/kg are bound in
the material.
In the production emissions of chlorine, mercury, ethylene-di-chloride (EDC,
hydrochloric acid and vinyl chlorides and more) can take place. It is most important to
control the emission of VCM and EDC due to the health risks. With regards to the
environment it is important to control the emission of chlorine substances.
When PVC is used in consumer products additives must be added, including pigments and
softeners. When seen from a toxicological and an eco-toxicological perspective the most
important stabilisers are lead, cadmium and certain organic connections. Cadmium is no
longer used as a stabiliser in Denmark.
Softeners are weight wise the largest group of additives. First and foremost DEHP is
used. DEHP is not acutely poisonous in aquatic environments, but can be acutely poisonous
for aquatic organisms and can have long-term harmful effects on the aquatic environment.
DEHP is potentially biodegradable in aerobe conditions if the temperature is high. DEHP
can be accumulated in sediments and soil where the temperature is relatively low.
Screening analysis show a week xen-oestrogen affect. DEHP is realised to the air and water
through production, use and deposition.
DIDP can be poisonous for aquatic organisms and is bio accumulative. CICP is
potentially degradable but is possibly degraded slower than DEHP.
In the use phase the environmental impact is dependent on whether the PVC is soft or
hard. In normal use the stabilisers are bound to the material and do not constitute a
problem. In the cleaning of for example vinyl floors or textiles some softener might be
released. In packing a certain migration of softener to the product will occur if there
has been direct contact with a product containing fat. Phthalate softeners are found in
different concentrations in the environment, especially in aquatic environments.
Sufficient knowledge on how they are transferred is not existent.
In Denmark the majority of waste is incinerated. Normally approx. 74 % of
PVC-material’s energy contents is used (29,52 MJ/kg). Herein the energy consumption
of transportation is not included. In the incineration of PVC sulphuric acid is produced.
Due to the smoke-gas’ environmentally harmful impact, chalk is usually used for
neutralisation. Heavy metals from pigments and stabilisers can be leached to the
environment. The slag that contains calcium chloride, heavy metals and dioxins is
deposited. It has been calculated that two-thirds of the chlorine that is created by waste
incineration stems from PVC-products. Precisely the chlorine-contents make it difficult to
deposit. The chlorine ions mobilise the heavy metals and the residual product must
therefore be treated as ‘problematic waste’.
PVC is a recyclable product and to some extent one can lower the waste quantities by
sorting out the waste. It is also questioned whether it is desirable to collect and
re-cycle PVC containing cadmium, instead of promoting an out-phasing of this. PVC is
degraded very slowly – if at all – in nature. Softeners are released from the
products and this can well be an important source of leaching to soil and water. The
further fate of softeners in the earth is not very well described.
The project report is written in English. A follow-up group with representatives from
the environmental authorities in Sweden, Norway, Germany, Holland and Belgium has
contributed with information and comments.
Author/ institution
Susanne Møller, Jørgen Larsen, Jens Erik Jelsen, Henriette Færgemann, Lars Mørck
Ottosen and Flemming Egtoft Knudsen – DTI/ Environmental Technique.
This report is subsidised by the National Council for Recycling and Cleaner Technology
ISSN no. 0105-3094
ISBN no. 87-7810-490-4
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