TLV^®/BEI^® Resources

ACGIH^® has a procedure that provides the public with an indication of where those chemical substances and physical agents under study fall in the development process. Tier 1 entries indicate which chemical substances and physical agents may move forward as an NIC or NIE in the upcoming year, based on their status in the development process. Tier 2 consists of those chemical substances and physical agents that will not move forward, but will either remain on or be removed from the Under Study list for the next year. For more information, please see the ACGIH^® TLV^®/BEI^® Development Process.

Tier 1 (may move forward with an NIC proposal in 2011)

Chemical Substances

Acetaldehyde Acetone Aliphatic hydrocarbon gases tert-Amyl methyl ether (TAME) Atrazine (and related symmetrical     triazines) Benzidine Bisphenol A Bromodichloromethane 1-Bromopropane Butane Calcium silicate, synthetic nonfibrous Carbonyl sulfide Clopidol Cyanogen chloride 2,4-D Diacetyl Dibutyl phthalate Diethylene glycol monobutyl ether Diethylhydroxyamine [DEHA] Ethane Ethyl formate Ethyl tert-butyl ether [ETBE]    (added 3/30/2010) Ethylidene norbornene Glycerin, mist

Isobutane Liquefied petroleum gas Methane Methomyl Methyl acetate Methyl acetylene (added 3/10/2010) Methyl formate Methyl isocyanate Methyl mercaptan (added 3/10/2010) Naphthalene Natural gas Nickel carbonyl Nitrogen dioxide n-Nonane (Nonane) Nonane, all isomers Pentaerythritol (added 3/10/2010) Phenyl isocyanate Phthalic anhydride o-Phthalodinitrile Propane Simazine Thioglycolic acid Titanium dioxide Tributyl phosphate Trichloroacetic acid 1,2,3-Trichloropropane

Tier 2 (will not move forward with an NIC proposal in 2011)

Chemical Substances

Acetophenone (added 3/10/2010) Antimony & compounds, as Sb    (added 3/10/2010) Antimony hydride (added 3/10/2010) Antimony trioxide (added 3/10/2010) Barium sulfate Benz[a]anthracene Benzo[a]pyrene Benzo[b]fluoranthene Boron tribromide Boron trifluoride sec-Butyl acetate Butylated hydroxytoluene (BHT) tert-Butyl hydroperoxide N-Butyl isocyanate Chlorine Chromite ore processing (Chromate),    as Cr (added 5/6/2010) Chromium and inorganic compounds,    as Cr (added 5/6/2010) Chromyl chloride (added 5/6/2010) Chrysene Coal tar pitch volatiles Cobalt & inorganic compounds,    as Co (updated 3/10/2010) Cobalt carbonyl (added 3/10/2010) Cobalt hydrocarbonyl (added 3/10/2010) Creosote Cyanogen bromide (added 3/10/2010) 3,3'-Dichlorobenzidine 1,3-Dichloro-5,5-dimethyl hydantoin Dicyclopentadiene Diethyl phthalate Di(2-ethylhexyl) phthalate    (added 3/10/2010) Diisobutyl ketone N,N-Dimethyl acetamide Dimethyl phthalate (added 3/10/2010) Dimethylformamide Dipropyl ketone Ethyl cyanoacrylate Ethyl isocyanate Ethylene norbornene (added 6/22/2010)

Fluorides, as F (added 5/6/2010) Fluorine (added 5/6/2010) Gasoline, all formulations Hexamethylene diisocyanate Iodoform Isophorone diisocyanate Lead & inorganic compounds,    as Pb (added 3/10/2010) d-Limonene Lithium hydride Lithium hydroxide Mercury, alkyl compounds Methylene bis(4-cyclohexylisocyanate) Methylene bisphenyl isocyanate [MDI] Methyl isoamyl ketone 1-Naphthylamine 2-Naphthylamine Nickel & inorganic compounds,    including Nickel subsulfide    (added 3/10/2010) Paraquat Pentachlorophenol Polycyclic aromatic hydrocarbons [PAHs] Polymeric MDI Stearates Stoddard solvent Terephthalic acid Tetramethyl succinonitrile Thiacloprid (added 3/10/2010) Triethanolamine Tungsten (added 3/10/2010) Tungsten carbide Vinyl acetate 5-Vinyl-2-norbornene Other Issues SEN Notation: Sensitization to be assigned as either respiratory sensitizer (RSEN), dermal sensitizer (DSEN) or both. (updated 3/10/2010)

Chemical Substances Removed from Under Study Effective 3/10/2010

Ethylene oxide