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 2020) 

Chemical Substances

Acetamiprid
Antimony hydride
Benzene
Benzidine
Buprofezin
1,3-Butadiene
Carbon monoxide
Chlorodiphenyl, 42% Cl
Chlorodiphenyl, 54% Cl
Clothianidin
Cyclohexane (added 6/12/2019)
Cyromazine
Diazinon
Dicamba
1,3-Dichloro-5,5-dimethyl hydantoin
1,2-Dichloropropane
Difluorodibromomethane
4,4-Dimethyloxazolidine
Dinotefuran (added 6/12/2019)
Dipropylene glycol methyl ether (previously
     listed as 2-Methoxymethylethoxy
     propanol
)
Enflurane
Epichlorohydrin
2,3-Epoxypropyl methacrylate
     (added 6/12/2019)
Ethyl benzene
Ethyl ether
Ethylene glycol dinitrate
Fluorides
Furan
Furfural
Furfuryl alcohol
Glyphosate
Halothane
Hexachloronaphthalene
sec-Hexyl acetate
Imazosulfuran
Imidachloprid
Iodine and Iodides
Isopropylamine
Ketene
Lead and inorganic compounds
Malathion

Methylcyclohexanone, mixed
     isomers (added 6/12/2019)
m-Methylcyclohexanone (added
     6/12/2019)

o-Methylcyclohexanone
p-Methylcyclohexanone (added 6/12/2019)
Mica
1-Naphthylamine
2-Naphthylamine
Neonicotinoids (added 6/12/2019)
Nitric acid
Parathion
Perchloryl fluoride
Phenothiazine
Phosgene
Phosphoric acid
Phosphorus (red)
Phosphorus (white)
Phosphorus (yellow)
Prometon
Prometryn
Propylene glycol dinitrate
Sevoflurane
Silicon carbide
Sodium silicate (added 6/12/2019)
Sodium sulfate
Styrene oxide (added 6/12/2019)
Subtilisins
Sulfur trioxide
Talc
Tetraethyl lead
Tetramethyl lead
Thiamethoxam (added 6/12/2019)
Tin, organic compounds
Titanium dioxide
Toluene
o-Toluidine
Trichlorfon
Triclopyr
Triclosan
Triethanolamine
Triflumizole
Trimethylbenzene, mixed isomers
Welding fume (added 6/21/2019)
Xylene

Tier 2 (will not move forward with an NIC proposal in 2020) 


Chemical Substances

Acetyl salicylic acid (added 6/12/2019)
Alkyl acrylates
Aluminum sodium dioxide
Antimony and compounds
Benzoic acid (added 6/12/2019)
Bifenazate
n-Butyl isocyanate
Carbon dioxide
Carbon nanotubes
Chloromethyl methyl ether
Cobalt carbonyl
Cobalt hydrocarbonyl
Copper
Crontonaldehyde (added 6/12/2019)
Cyclopentane (added 6/12/2019)
Diacetyl (added 6/12/2019)
1,1-Dichloro-1-nitroethane
3,3ʹ-Dichlorobenzidine
Diesel exhaust
Diiodomethyl p-tolyl sulfone
1,2-Dimethoxyethane
Ethyl acrylate
2-Ethyl hexane-1-ol (added 6/12/2019)
Ethylene oxide
Germanium tetrahydride
Hafnium and compounds
Hydrogen peroxide (added 6/12/2019)
Indium and compounds
Isoprene (added 6/12/2019)
4,4ʹ-Isopropylidene diphenol
     (added 6/12/2019)

Lindane
Manganese cyclopentadienyl tricarbonyl
Methyl acrylate
Methyl n-butyl ketone
2-Methyl-2-butene (added 6/12/2019)
2-Methylcyclopentadienyl manganese
     tricarbonyl
Methylene bisphenyl isocyanate
Metribuzin
Nickel and inorganic compounds,
     including Nickel subsulfide
Octachloronaphthalene
Pentaborane
Propane sultone
n-Propyl nitrate
Quinone
Silicic acid
Sodium hypochlorite
Stoddard solvent
Tetrachlorophthalic anhydride
Tetrachlorvinphos
1,2,3,6-Tetrahydrophthalic anhydride
Trichloronaphthalene
Trifloxystrobin
Trimethyl phosphite
Uranium and compounds
Vinylidene chloride
Vinylidene fluoride


Chemical Substances Removed from Under Study Effective 6-12-19 

Catechol
2,3-Pentanedione
Polycyclic aromatic hydrocarbons