Chemical Substances and Other Issues Under Study (TLV®-CS)

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 indicates 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 2019) 

Chemical Substances

Acrylamide
Antimony hydride
Antimony trioxide
Benzene
Benzidine
Buprofezin
4-tert-Butylbenzoic acid
Chlorodiphenyl, 42% Cl
Chlorodiphenyl, 54% Cl
Cyclohexene
Cyromazine
Diazinon
Dicamba (added 6-5-18)
1,3-Dichloro-5,5-dimethyl hydantoin
1,2-Dichloropropane
Di(2-ethylhexyl)phthalate
Difluorodibromomethane
Enflurane (added 6-5-18)
Epichlorohydrin
Ethylene glycol dinitrate
Fluorides
Formamide
Furan
Glyphosate
Halothane
Hexachloronaphthalene
Hexamethylenetetramine
Hexazinone
Imidacloprid
Isoflurane
Isopropylamine
Lead and inorganic compounds
Manganese cyclopentadienyl tricarbonyl
Methyl isobutyl carbinol
Methyl n-butyl ketone
o-Methylcyclohexanone

2-Methylcyclopentadienyl manganese
     tricarbonyl
Mica
Nitroglycerin
Parathion
Perchloryl fluoride
Phenothiazine
Phosphine (added 6-5-18)
Phosphorus (red) (added 6-5-18)
Phosphorus (white)
Phosphorus (yellow)
Prometon
Propylene glycol dinitrate
Resin acids (added 6-5-18)
Resin acids from rosin based solder
Rosin core solder thermal decomposition
     products (colophony)
Sevoflurane (added 6-5-18)
Silicon carbide
Subtilisins (added 6-5-18)
Sulfur pentafluoride
Sulfur trioxide
Talc (added 6-5-18)
Tetraethyl lead
Tetramethyl lead
Thiodicarb
Tin, organic compounds
Titanium dioxide
Titanium tetrachloride
o-Toluidine
Trichlorfon (added 6-5-18)
Triclopyr
Triclosan
Triethanolamine
Triflumizole

Tier 2 (will not move forward with an NIC proposal in 2019) 

Chemical Substances

Alkyl acrylates
Aluminum sodium dioxide
Antimony and compounds
Bifenazate
1,3-Butadiene
n-Butyl isocyanate
Carbon dioxide
Carbon monoxide
Carbon nanotubes
Catechol
Chloromethyl methyl ether
Cobalt carbonyl
Cobalt hydrocarbonyl
Copper
3,3′-Dichlorobenzidine
1,1-Dichloro-1-nitroethane
Dicyclopentadienyl iron
Diesel exhaust
Diiodomethyl p-tolyl sulfone
1,2-Dimethoxyethane
4,4-Dimethyloxazolidine
Ethyl acrylate
Ethyl ether
Ethylbenzene
Ethylene oxide
Furfural
Furfuryl alcohol
Germanium tetrahydride
Hafnium and compounds
sec-Hexyl acetate
Indium and compounds
Ketene
Lindane
Malathion

2-Methoxymethylethoxy propanol
Methyl acrylate
Methylene bisphenyl isocyanate
Metribuzin
1-Naphthylamine
2-Naphthylamine
Nickel and inorganic compounds,
     including Nickel subsulfide
Nitric acid
Octachloronaphthalene
Pentaborane
2,3-Pentanedione
Phosgene
Phosphoric acid
Polycyclic aromatic hydrocarbons
Prometryn
Propane sultone
n-Propyl nitrate
Quinone
Silicic acid
Sodium hypochlorite
Stoddard solvent
Tetrachlorophthalic anhydride
Tetrachlorvinphos
1,2,3,6-Tetrahydrophthalic anhydride
Toluene
Trichloronaphthalene
Trifloxystrobin
Trimethylbenzene (mixed isomers)
Trimethyl phosphite
Uranium and compounds
Vinylidene chloride
Vinylidene fluoride
Xylene 


Chemical Substances Removed from Under Study Effective 6-5-18

Bromodichloromethane