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Substances Under Consideration

Substances listed below are under consideration—but not selected—for possible review for the Report on Carcinogens. You can provide information such as citations, new studies, or scientific issues on any of the substances.

View the list of selected substances that are currently under review for the report.

New Topics or Substances for Possible Review

List of nominated topics
Topic CASRN Primary Uses or Exposures FRN Public Comments
A
Alkenylbenzenes
(selected dietary: estragole, myristicin, isosafrole)
140-67-0
607-91-0
120-58-1
Naturally occurring organic chemicals used primarily as an additive, flavoring, or fragrance in food products, but may also be in other products such as cosmetic and cleaning agents. January 19, 2012
(PDF HTML)
Public Comments
B
C
Carbon black 1333-86-4 Family of products consisting of elemental carbon in the form of colloidal particles that rapidly form aggregates. The products are used primarily for rubber reinforcement, but are also used as black pigments and for electrical conductivity purposes. January 19, 2012
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Public Comments
Chlorothalonil (2,4,5,6-tetrachloro-isophthalonitrile) 1897-45-6 A broad-spectrum pesticide used on a variety of vegetable and orchard crops. It is also used as a mildewicide added to paint and other surfaces. September 20, 2013
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Public Comments
D
Decalin 91-17-8 Industrial solvent primarily for naphthalene, fats, resins, oils, and waxes. September 20, 2013
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Public Comments
Dibromoacetonitrile 3252-43-5 Water disinfection byproduct (haloactonitrile) formed as a result of the reaction of chlorine oxidizing compounds with natural organic matter found in drinking water. October 7, 2015
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Public Comments
Diesel exhaust particulates -

A mixture of combustion products of diesel fuel; the exact composition of the mixture depends on the nature of the engine, operating conditions, lubricating oil, additives, emission control system, and fuel composition. Occupational exposure occurs primarily among miners (who use diesel power equipment), railroad workers and transportation workers such as truck drivers.

First listed as Reasonably Anticipated to be a Human Carcinogen in the 12th RoC.

January 19, 2012
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Public Comments
E
Ethylbenzene 100-41-4 An alkylated benzene used primarily for the manufacture of styrene. January 19, 2012
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Public Comments
F
Flame retardants
  • Pentabromodiphenyl ether mixture (DE-71)
  • Tetrabromobisphenol A (TBBPA)
32534-81-9
79-94-7

Pentabromodiphenyl ether mixture (DE-71) is a flame retardant mixture used in furniture materials; voluntarily phased out in the United States in 2004. Widespread occurrence in the environment.

Tetrabromobisphenol A (TBBPA) is a brominated flame retardant used in circuit boards, to encapsulate electronics, and intermediate for other flame retardants.

October 7, 2015
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Public Comments
Fluoride - Mineral primarily used to prevent tooth decay; added to municipal water supplies and dental products (e.g., toothpaste). Primary exposure to public is via drinking water and use of fluorinated products. Workers may be exposed by inhaling fluoride dust. October 7, 2015
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Public Comments
G - H
I
Indium compounds - Indium compounds are chemicals that include the metal indium. Indium phosphide is used primarily in the semiconductor industry; however, most of the semiconductor industry in the U.S. is silicon based. Other indium compounds (such as indium tin oxide) are primarily used in optoelectronics and flat panel display technology. January 19, 2012
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Public Comments
Iron (excess) or iron overload 7439-89-6 Iron is a transition metal that exists mainly in the ferrous (2+) and ferric (3+) oxidation states in biological systems. It is used for medical treatment, as well as for other consumer and industrial needs. It is also found naturally in food. Iron overload disorders can be hereditary, acquired, or iatrogenic. January 19, 2012
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Public Comments
J - L
M
Meat-related exposures
  • Consumption of red meat
  • Consumption of processed meat
  • Consumption of meat cooked at high temperatures
-

Red meat refers to meat that has more red than white fibers such as beef, goat, lamb and pork. People are exposed to red and processed meat in their daily diet. In the United States, daily total meat intake is 128 g, of which 55% is red meat.

Processed meat is meat that is preserved by smoking, curing, salting and adding chemical preservatives. In the United States, daily processed meat is estimated to be 23 g.

Cooking meat at high temperatures refers to cooking methods including grilling and pan frying as well as the final cooking temperature or "doneness" of the meat. High temperature cooking methods lead to the formation of many chemical substances including heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs).

September 9, 2016
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Public Comments
2-Methylimidazole 693-98-1 Used in the manufacture of pharmaceuticals, photographic chemicals, dyes and pigments, agricultural chemicals, and rubber. Also found in tobacco smoke. September 20, 2013
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Public Comments
4-Methylimidazole 822-36-6 Used in the manufacture of pharmaceuticals, photographic chemicals, dyes and pigments, cleaning and agricultural chemicals, and rubber. Also found in tobacco smoke and food and drinks containing caramel coloring. September 20, 2013
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Public Comments
Methyl isobutyl ketone 108-10-1 Solvent for paints, varnishes and other agents, and for industrial extraction processes. Also denaturant for rubbing alcohol. September 20, 2013
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Public Comments
N
Nitro PAHs as a class - Found in particulate emissions from many combustion sources, most notably, diesel exhaust. September 20, 2013
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Public Comments
O
P
Pentabromodiphenyl ether mixture (DE-71) (see Flame retardants)
Perfluorooctanoic acid (PFOA) 335-67-1 Used in the manufacturing of fluoropolymers. Fluoropolymers are primarily used to provide non-stick to cookware and waterproof membranes for clothing. They are also used in other applications and have fire-resistance properties. September 20, 2013
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Public Comments
Q - S
T
Tetrabromobisphenol A (TBBPA) (see Flame retardants)
Tris-(1,3-dichloro-2-propyl) phosphate (TDCPP) 13674-87-8 Organophosphate flame retardant used in the polyurethane foam padding in furniture and automobiles. September 20, 2013
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Public Comments
U
V
Vinylidene chloride 75-35-4 Chemical intermediate used to make a variety of polymers that are used to make consumer products (e.g., plastic food packaging films, binders). October 7, 2015
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Public Comments
W
Wood smoke - Smoke from wood burning fireplaces and stoves. September 20, 2013
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Public Comments
X - Z

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