Substance fact sheet
The National Pollutant Inventory (NPI) provides information on the types and amounts of pollutants being emitted in the Australian community.
This page provides facts about biphenyl (1,1-biphenyl). It describes how you might be exposed to this substance, how exposure might effect you and the environment, common uses, comparative data about biphenyl (1,1-biphenyl) and its physical and chemical properties.
For more information about some of the terms used in this page, see the NPI glossary.
The National Pollutant Inventory (NPI) holds data for all sources of biphenyl (1,1-biphenyl) emissions in Australia .
Workers exposed to biphenyl fumes for short periods of time have experienced nausea, vomiting, irritation of the eyes and respiratory tract, and bronchitis. These acute effects are not likely to occur at levels of biphenyl that are normally found in the environment.
Breathing small amounts of biphenyl over long periods has caused damage to the liver and nervous system of exposed workers. Other human health effects associated with exposure to small amounts of biphenyl over long periods are not known. Laboratory studies show that repeat exposure to large amounts of biphenyl by ingestion damages the kidney and blood, and reduces growth and life expectancy of animals. Limited evidence suggests that repeat exposure to biphenyl dust adversely affects the respiratory tract of laboratory animals.
TWA: 0.2 ppm 1.3 mg/m³
The substance can be absorbed into the body by inhalation and by ingestion.
You may be exposed to biphenyl if you live near an industrial site where biphenyl is used, or a waste dump where it has been discarded. At these sites, biphenyl may be carried in the air on dust particles. If you work in an industry that produces the chemical unintentionally as a by-product or uses biphenyl, you may also be exposed to biphenyl particles or dust particles that carry biphenyl and possibly get it on your skin.
Exposure to biphenyl can occur through eating citrus fruits that have been wrapped in paper impregnated with biphenyl.
Exposure to biphenyl can also occur through contact with biphenyl-contaminated soil, dust particles, or industrial releases into the environment.
See Sources for more information.
Worksafe Australia
Maximum 8-hour time weighted average (TWA) exposure: 0.2 ppm.
The Australian NOHSC National Exposure Standards Database link is probably the most useful source of information.
Note that the emissions data in the NPI database is not directly comparable with these guidelines.
Biphenyl has high acute toxicity, but low chronic toxicity, to aquatic life. Biphenyl is expected to be non-toxic to terrestrial organisms at levels that are normally found in the environment.
Volatilisation and sorption are important in the transport of biphenyl in water. As it is a solid that binds to soil, biphenyl will only move slowly through the ground and enter groundwater. The half-life of biphenyl in water is up to about 20 days.
Plants and animals may store small amounts of biphenyl.
About 59% of biphenyl will eventually end up in air; about 15.6% will end up in water; and the rest will be divided about equally between terrestrial soils and aquatic sediments.
Biphenyl dissolves poorly when mixed with water. Most releases of biphenyl are to air. In air, biphenyl breaks down to other chemicals or settles as dry deposits to water or land. Biphenyl attaches to solid material in water. Microorganisms living in water and in soil break down biphenyl to other chemicals.
The dominant tropospheric loss process for biphenyl is reaction with the photochemically produced hydroxyl (OH) radical. The calculated half-life biphenyl due to reaction with the OH radical is estimated to be 1.4 days. The products observed are 2-hydroxybiphenyl and, in much lesser amounts, 3- and 4-hydroxybiphenyl, and 3-nitrobiphenyl.
No national guidelines.
Its major uses are in the production of heat-transfer fluids (for example, as an intermediate for polychlorinated biphenyls) and dye carriers for textile dyeing. Lesser uses are as a mould retardant in citrus fruit wrappers, in formation of plastics, optical brighteners, and hydraulic fluids.
Releases from industries producing, using, or handling biphenyl, or where it is used as a heat transfer agent (for example, electrical transformers).
Sub-threshold facilities.
Biphenyl enters the aquatic environment in wastewater effluents from textile mills that use it as a dye carrier; from industrial processes; and from leaking heat exchangers.
Biphenyl is released to the atmosphere as a fume during its use as a heat transfer fluid and, to a lesser extent, by volatilisation from soil and water.
It occurs naturally in trace amounts, mostly in crude oil.
No information.
Where used as a mould retardant in citrus fruit wrappers, in formation of plastics, optical brighteners, and hydraulic fluids.
No consumer products should intentionally contain biphenyl. However, it may be found as a contaminant in some foods, and possibly in dyed products such as textiles.
Approximately 400 substances were considered for inclusion on the NPI reporting list. A ranking and total hazard score was given based on health and environmental hazards and human and environmental exposure to the substance.
Biphenyl (1,1-biphenyl) was ranked as 53 out of 400. The total hazard score taking into account both human health and environmental criteria is 4.0.
On a health hazard rating of 0 - 3 biphenyl (1,1-biphenyl) registers 1.0. A score of 3 represents a very high hazard to health, 2 represents a medium hazard and 1 is harmful to health.
On an environmental rating of 0 - 3 biphenyl (1,1-biphenyl) registers 3.0. A score of 3 represents a very high hazard to the environment and 0 a negligible hazard.
Factors taken into account to obtain this ranking and these scores include the extent of the material's toxic or poisonous nature and/or its lack of toxicity, and the measure of its ability to remain active in the environment and whether it accumulates in living organisms. It does not take into account exposure to the substance. Environmental exposure is reflected in the NPI rank for this substance (see comparative data below). A substance that scores highly as an environmental hazard is oxides of nitrogen at 3.0 and one of the lower scores is carbon monoxide at 0.8. A substance that scores highly as a health hazard is arsenic at 2.3 and one of the lowest scores is ammonia at 1.0.
| Substance name | Biphenyl (1,1-biphenyl) |
| CASR number | 92-52-4 |
| Molecular formula | C12H10 |
| Synonyms | phenylbenzene; 1,1'-biphenyl; 1,1'-diphenyl; diphenyl; bibenzene; lemonene; phenador-x; phph; xenene |
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Physical properties: Formula mass 154.21 |
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| Chemical properties: Biphenyl is one of the most thermally stable of all organic compounds. It is combustible at high temperatures producing carbon dioxide and water when combustion is complete. Partial combustion produces carbon monoxide, smoke, soot, and low molecular weight hydrocarbons. |
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There is more information that may be useful in understanding some of the issues surrounding the NPI.