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Isoproturon

Ipuron, IPU, Panron

SPRI Emission Reporting Threshold
0.01 Kg/yr Pollutant Emissions to Water
0.01 Kg/yr Pollutant Emissions to Waste Water
1.00 Kg/yr Pollutant Emissions to Land
Disclaimer
This sheet is a generic summary, designed to give the reader a basic level of background information about the substance in question. Great care has been taken to represent as effectively and correctly as possible the broad range of (not necessarily consistent) information which is available from a variety of sources. The reader must accept therefore that this sheet has no legal status and cannot be relied upon in any legal proceedings. SEPA disclaims any responsibility or liability whatsoever for errors and omissions in this sheet.
What is it?
Under normal conditions, Isoproturon (IPU) is found as colourless crystals. It melts at 158 degrees celsius. IPU is not broken down by light and is stable in mildly acidic or alkaline solutions. In strong alkaline solutions or when heated, it is however quickly broken down. IPU is soluble in water and some organic (carbon-containing) solvents.
What is it used for?
IPU is used as a herbicide, applied to soils before plants emerge and also to soils around growing crops. It is used mainly to control grasses and other weeds amongst cereal crops. It works by interfering with the way in which plants convert the sunlight to energy.
Where does it come from?
The most significant releases of IPU occur during its use as a herbicide. Releases may also occur during its manufacture, transport and storage. There are not thought to be any natural sources of IPU to the environment.
How might it affect the environment?
If recommended guidelines for use are adhered to, IPU applied as a herbicide is unlikely to damage the environment. It is broken down fairly easily by microbes in soils, producing Carbon dioxide and other products. Some IPU can end up in water bodies, where it can be very persistent and can cause significant damage as it is very toxic to aquatic organisms. It is not considered likely that IPU pollution has any effects on the global environment.
How might exposure to it affect human health?
Isoproturon can enter the body either by the inhalation of air containing isoproturon, ingestion of contaminated water, or by dermal contact with isoproturon. There is little evidence for the full effects of exposure to isoproturon on human health however exposure to isoproturon may cause adverse health effects. Inhalation of air containing isoproturon can irritate the upper respiratory tract. Exposure to isoproturon may also affect the blood. Dermal contact with isoproturon may cause skin irritation. Eye contact can cause irritation. The International Agency for Research on Cancer has not designated isoproturon in terms of its carcinogenicity. However, exposure to isoproturon at normal background levels is unlikely to have any adverse effect on human health.
What steps are being taken to limit the potential impacts?
Releases of IPU are controlled through the UK Pollution, Prevention and Control (PPC) Regulations, the Food and Environmental Protection Act (FEPA 1985) and the Control of Pesticides Regulations (COPR 1986). As a VOC, levels of IPU in air are also controlled through the UK National Air Quality Strategy. IPU is approved for authorised use as a pesticide in the UK (including Scotland) in the Pesticide Safety Directorate. European Directives concerned with releases of IPU include that which controls pollution of the aquatic environment by dangerous substances (76/464/EEC), that which designates maximum allowed levels for pesticide residues in fruit and vegetables (93/58/EC) and it is also listed as a "priority substance" for action under the Water Framework Directive. IPU is also regulated internationally through the OSPAR Convention, which protects the marine environment of the north-east Atlantic Ocean.