Context
- Diisodecyl-phthalate (DIDP) and
Diisononyl-phthalate (DINP) are
two closely related substances
that are mainly used as additives
in plastics to make them more flexible.
Their widespread use in everyday
products, from floorings and shoe
soles to toys has raised some concerns
about their safety. Do DIDP and
DINP pose a risk to health or the
environment?
Phthalates
are widely used as additives in a range
of plastics and other materials that are
found in many consumer products. They
make plastics, such as PVC,
soft and flexible. They are not chemically
bound to plastics, so they can be released
from consumer products into the environment.
There is public concern about phthalates
because of their widespread use and occurrence
in the environment as well as their potential
effects on human health.
There
is a wide range of different phthalates,
which each have specific properties,
uses, and health effects. In the
European Union, five of the most
widely used phthalates are currently
being reviewed by the European Chemicals
Bureau (DEHP, DBP, DINP, DIDP, and
BBP).
So far, EU
Risk Assessment Reports have only been
published for three of these phthalates
which are addressed in this study: DIDP,
DINP,
and DBP.
Because of the strong similarities between
the first two, they will be described
together in this study. More...
DIDP
and DINP
are acronyms that each refer to certain
mixtures of phthalates.
They have a common core
structure with two long chains of molecules
attached to the core. Most of these chains
contain 10 carbon atoms in the case of
DIDP, and 9 carbon atoms in the case of
DINP. The arrangement of the molecules
in the chains can differ and this is why
DIDP and DINP are mixtures of closely-related
substances.
DIDP and DINP are sticky,
oily liquids. They are soluble
in fat and not very soluble in water.
More...
In 1994, over 200 000
tonnes
of DIDP
and 107 000 tonnes of DINP
were produced annually in the European
Union and production is expected to increase
further.
They are used mainly as
a plasticiser
in PVC
that is used to make film, sheeting, coated
products, flooring, roofing, wall coverings,
hoses, tubing, wires, cables, injection
moulded shoe soles, car undercoating and
sealants.
They are also used in
vinyl resins other than PVC, in cellulose
ester plastics as well as in adhesives,
paints and printing inks. More...
Although DIDP
and DINP
are mixtures and each component can behave
slightly differently in the environment,
an overall picture can be drawn.
More...
3.1
DIDP and DINP present in the environment
can remain for a long time in soil and
sediment. They can also concentrate in
organisms living in water. More...
3.2
Most of the DIDP and DINP released into
the general environment results from the
use and disposal of PVC
products containing them. DIDP and DINP
can go into waste
water, surface
water and into air. More...
3.3
Local concentrations in the environment
are particularly high around industrial
sites where DIDP and DINP are either produced
or used to make plastics and other products.
At those sites concentrations of DIDP
and DINP in water, sediment and soil are
highest. More...
3.4
DIDP and DINP do not appear to
have adverse effects on organisms in the
environment. They are not toxic to microbes,
plants or animals. More...
3.5 Despite the presence of DIDP
and DINP in the environment, it is concluded
that:
the levels found,
they do not present a risk to the environment,
that no further testing
is needed, and
that no further risk
reduction measures need to be taken.
Exposure
of humans may occur because DIDP
and DINP
are present in the general environment,
in the workplace and in consumer products.
4.1
The highest exposures can occur in certain
workplaces where DIDP, DINP, or products
that contain them are produced or used.
More...
4.2
Exposure of the general public
is about 50 times lower than workplace
exposure. For infants, the level of exposure
varies depending on whether they have
contact with plastic toys and baby care
equipment containing DIDP
or DINP.
If they have contact with such toys their
exposure can be much greater. More
on consumers exposure... More
on overall exposure...
5.
What health effects can DIDP and
DINP cause in laboratory animals?
DIDP
and DINP
are absorbed well when swallowed
or breathed in, but are poorly absorbed
through the skin.
In laboratory animals
the main effects of DIDP and DINP
are on the liver and include cancer.
Humans are thought to be much less
sensitive to these liver effects
and the cancer is caused by a mechanism
which is only seen in rodents and
not in humans. DIDP
and DINP
also affect survival of rat offspring.
DIDP does not appear
to interfere with hormones
and reproduction, but DINP may have
some impact on male hormones. More...
6.1
When human exposures
are compared with the lowest amounts needed
to cause effects in laboratory animals,
the margin of safety is sufficient for
workers not to be considered at risk. More...
6.2
Exposure of the general public
is lower than that of workers, thus adults
and children above the age of three are
not considered to be at risk.
In the worst case scenario
for newborns and infants, which assumes
that all the phthalates
in toys and baby equipment are DIDP,
the margin of safety is not sufficiently
protective.This is because infants can
absorb phthalates when putting toys into
their mouth. If toys are excluded from
exposure estimates, then infant exposures
are not of concern.
For DINP,
the margins of safety are considered sufficient,
even for infants exposed to toys containing
DINP. More...
The European Union Risk
Assessment Report on DIDP
and DINP
(the source of the present summary) concluded
that there is no need for further information
or testing, or for further risk reduction
measures beyond those already taken, except
to limit risks should DIDP be used in
toys. More...
The Scientific Committee
on Toxicity, Ecotoxicity and the Environment
has commented on the European Union Risk
Assessment Report on DINP. It did not
agree with several of the conclusions
about environmental effects and considers
that more research is necessary.
Phthalates
have played an important role in the creation
of plastics and other materials that have
many versatile uses in industry, in medicine
and in consumer products.
In view of
more recent research, raising concerns
about possible environmental and health
effects, the risks of exposure
to phthalates are being kept under close
review by national and international bodies.
The most
recent EU reviews on DIDP,
DINP
and DBP
conclude that:
more research may be necessary on
the environmental effects of DIDP and
DINP;
DIDP in toys may pose a risk;
in some workplaces, exposure to DBP
should be reduced;
release of DBP in to the air from
some workplaces should be reduced.
Other phthalates
are currently being assessed by the European
Chemicals Bureau.
GreenFacts
comment:
Other
EU reviews are currently underway and
the information will be posted on this
website as soon as it becomes available:
DEHP (Di-Ethyl-Hexyl-Phthalate)
the most commonly used phthalate
1.
What are the properties of DIDP and DINP?