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Permethrin

Permetrina, Ambush, Pounce, Perto

SPRI Emission Reporting Threshold
0.001 Kg/yr Pollutant Emissions to Water
0.001 Kg/yr Pollutant Emissions to Waste Water
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?
Technical grade (impure) Permethrin is available commercially in a number of forms: as a light brown coloured liquid; as crystals, dust or powder; or in a very concentrated thick liquid. All forms have no smell. Pure Permethrin melts at around 35 degrees celsius. Permethrin is stable under most circumstances, but will be broken down in alkaline conditions or when burned, producing toxic fumes in the process. Permethrin is insoluble in water, but will mix with most organic (carbon-containing) solvents.
What is it used for?
Permethrin is an insecticide, chemically very similar to natural insecticidal substances found in certain plants. It is used to control insect pests amongst fruit trees or bushes, vines, and tobacco and cotton plants. It is also used to control pests in storage facilities, public buildings and domestic homes and gardens.
Where does it come from?
The most significant releases of Permethrin occur during its application as an insecticide in a variety of situations. Permethrin may also be released during its manufacture, transport and storage. Although chemically similar to naturally occuring substances in plants, there are not thought to be any natural sources of Permethrin to the environment.
How might it affect the environment?
When guidelines for use are followed, Permethrin is unlikely to have any negative impact on non-target wildlife or the environment. At higher levels Permethrin is however very toxic to aquatic life and some non-target insects such as bees. Accidental spills of large amounts may give rise to sufficiently high concentrations to cause harm. There is also limited evidence to suggest that Permethrin may interfere with the action of animal hormones, that it is an "endocrine disruptor" - but expert opinion is divided as to whether or not significant effects do occur. Permethrin is not persistent in the environment - it is broken down fairly easily in soils and water bodies. It is not considered likely that Permethrin pollution has any effects on the global environment.
How might exposure to it affect human health?
Permethrin can enter the body either by inhalation of air containing permethrin, ingestion of contaminated food or water, or by dermal contact with permethrin. Inhalation of air containing permethrin can lead to a number of symptoms including a sore throat, runny nose, cough, breathing difficulties, wheezing, chest pain, pneumonitis and in extreme cases respiratory failure and cardiopulmonary arrest. Ingestion of permethrin can lead to nausea, vomiting and abdominal pain. Dermal contact with permethrin can cause skin irritation and dermatitis. Eye contact can cause irritation. The International Agency for Research on Cancer has designated permethrin as being not classifiable as to its carcinogenicity to humans. However, exposure to permethrin 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 Permethrin 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). Permethrin is listed as authorised for safe use in the UK in the Pesticide Safety Directorate. European Directives regulating levels of Permethrin include that concerned with pollution of the aquatic environment (76/464/EEC) and that which designates maximum allowed levels for pesticide residues in fruit and vegetables (93/58/EC).