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Title 40

Displaying title 40, up to date as of 6/04/2026. Title 40 was last amended 6/04/2026.
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Table 1 to Subpart XX of Part 63—Hazardous Air Pollutants

Hazardous air pollutant CAS No.
Benzene 71432
1,3-Butadiene 106990
Cumene 98828
Ethyl benzene 100414
Hexane 110543
Naphthalene 91203
Styrene 100425
Toluene 108883
o-Xylene 95476
m-Xylene 108383
p-Xylene 106423