What type of substance is it?
1,4-dichlorobenzene is man-made chemical. It is as a white solid with a penetrating odour. It is a long-lasting in the environment. It is also a VOC (Volatile Organic Compound), which can contribute to the formation of harmful ground-level ozone.
How is it released?
1,4-dichlorobenzene is released into the environment during its use as an insecticidal fumigant (as an ingredient in moth balls) and from deodorising tablets used in WCs. There are believed to be no natural sources of dichlorobenzene.
Scientific name: 1,4-Dichlorobenezene, para dichlorobenzene, p-dichlorobenzene; C6H4Cl2
Other names: DCB, para DCB, p-DCB, various trade names such as Paramoth, paracide etc.
CAS Number: 106-46-7
1,4-Dichlorobenzene is appreciably volatile. It breaks down in the air to harmless products in about a month. It does not dissolve appreciably in water but is very soluble in organic solvents, fats and oils. It is not easily broken down by microbes in soil or water. It can be taken up and retained by fish and plants. Dichlorobenzene is a volatile organic compound (VOC). At ground level, VOCs react with other air pollutants and contribute to the formation of potentially harmful concentrations of ozone in the lower atmosphere.
As a moth killer and WC deodorant. It is also used to make certain resins and as a general insecticide.
At room temperature, 1,4-dichlorobenzene is a white solid with a penetrating odour. It is very insoluble in water, but dissolves readily in many organic solvents.
Where is it released?
1,4-Dichlorobenzene is released to the environment through its use as an insecticide and deodorant, and also from possible accidental releases from manufacture, storage and transport. There are believed to be no natural sources.
Local environmental effects
Large releases to the environment can be expected to harm wildlife, in view of its insectidical properties, persistence and possible ability to bioaccumulate. As a VOC it can be involved in reactions with other air pollutants that form ground-level ozone, which can cause damage to crops and materials as well as having potential effects on human health.
Global environmental effects
Unknown. Volatility, persistence and possible ability to bioaccumulate gives rise to concern that 1,4-dichlorobenzene may be a global pollutant.
Possible health concerns
Excessive exposure to 1,4-dichlorobenzene may affect the blood, brain, eye, kidney, liver, lung and skin. The Environment Agency aims to ensure that environmental exposures are too low to harm health.
Why was this substance selected for the Pollution Inventory?
Included in : Environment Agency categorisation as a hazardous Volatile Organic Compound (VOC)
Standard risk phrases for the pure substance
The standard risk phrases provided here are generally those used by suppliers of chemicals to describe substances - for example on packaging materials. The most important source of these phrases are the CHIP Regulations - Chemicals (Hazard Information and Packaging for Supply) - provided by the Health and Safety Executive. Some substances do not have CHIP risk phrases and in these circumstances we have used other risk phrases, the sources of which are indicated.
CHIP Phrase(s) : Xi: Irritant; N: Dangerous to the Environment; R36: Irritating to the eyes; R50/53: Very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment
Controlling legislation and international agreements
1,4-Dichlorobenzene is not listed under the Pesticide Safety Directorate as being authorised for use in the UK. The primary UK legislation controlling pesticides is the Food and Environmental Protection Act (FEPA 1985 - as amended) and the Control of Pesticides Regulations (COPR 1986) made under this Act. The UK legislation implementing the EC Directives are the Surface Waters (Dangerous Substances) (Classification) Regulations, 1997 (SI 1997/2560) and Pollution Prevention and Control Regulations. The UK is also committed to reduce VOC emissions under its Air Quality Strategy. 1,4-Dichlorobenzene is listed for evaluation under the EU evaluation of existing substances regulation 793/93 and also regulated under Directive EC 76/464/EEC on the discharge of certain dangerous substances to the aquatic environment. As a VOC the main international legislation are the UN/ECE Convention on Long-Range Transboundary Air Pollution and Basel Conventions. It is also listed as a candidate substance for selection, assessment and prioritisation under the OSPAR and Helsinki Conventions.These factsheets have been compiled to provide users with information on the Pollution Inventory substances and represent our best efforts to summarise a large number of disparate and sometimes conflicting data sources. We emphasise that this information describes potential hazards rather than actual effects and that the Environment Agency seeks to regulate releases to minimise emissions and hence any risk of detrimental effects occurring.