Synopsis: |
An assessment of the risks to human health and the environment posed by exposure to N-phenyl-1-naphthylamine, a lipophilic crystalline solid that is used as an antioxidant in various lubrication oils and as a protective agent and antioxidant in rubber and rubber mixtures for various products, including tyres. The report cites evidence that the chemical may be released to soil and surface waters from the leakage of lubrication oils or leaching from decaying tyres and rubber products. Emission to the atmosphere may arise from exhaust gases during production and processing, and during the vulcanization of rubber mixtures. Presence in the environment is expected to be low. Limited studies indicate that the chemical is distributed to soil, sediment and water, and to a much smaller degree, to air, suspended sediment, and biota. In view of its moderate to high potential for sorption to organic soil constituents and its limited mineralization in soil, the chemical is likely to have geoaccumulation potential. Studies demonstrate high acute toxicity in fish and Daphnia. Avaliable data were judged inadequate to allow an assessment of human exposure.Laboratory studies indicate that N-phenyl-1-naphthylamine is well-absorbed and extensively excreted after ingestion. Although the chemical shows low acute oral toxicity in laboratory animals and is neither a skin nor an eye irritant, studies conducted in both animals and humans suggested that N-phenyl-1-naphthylamine may be a skin sensitizer. The report recommends that dermal contact with the chemical should be avoided. |