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Nomination Summary for Compressed Natural Gas Engine Emissions (N21003)

Nominated Substances: Compressed Natural Gas Particulate Matter

Nomination Date: 01/12/2010

Nominator: Private Individual

Rationale: Diesel Particulate Matter is classified as Probably Carcinogenic to Humans by IARC, and Reasonably Anticipated by NTP based on sufficient evidence of increased lung tumors in rats. Gasoline engine emissions are classified at possibly carcinogenic by IARC. Emissions from compressed natural gas engines have not been tested to in the bioassay to my knowledge. CNG engines emit lower mass than diesel, but similar number of particles.

NTP Principles: not specified

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