Carcinogens styrene

While styrene is not confirmed as a carcinogen, it is considered a suspect carcinogen. Styrene liquid is inflammable and has sufficient vapor pressure at slightly elevated temperatures to form explosive mixtures with air. Properly inhibited and attended, styrene can be stored for an extended period of time. 

Adducts to hemoglobin are perhaps the most useful means of biological monitoring by adduct formation. Hemoglobin is, of course, present in blood, which is the most accurate type of sample for biological monitoring. Adducts to blood plasma albumin are also useful monitors and have been applied to the determination of exposure to toluene diisocyanate, benzo(a)pyrene, styrene, styrene oxide, and aflatoxin Bj. The DNA adduct of styrene oxide has been measured to indicate exposure to carcinogenic styrene oxide.12... 

Toxicology Causes eye, skin irritation inh. of vapors and/or aerosols may cause irritation to the mucous membranes, eyes, nose, and respiratory passages contains possible carcinogen (styrene) TSCA listed Precaution Incompat. with strong oxidizers, strong acids, materials reactive with hydroxyl compds. 

Styrene is Hsted in the U.S. Toxic Substance Control Act (TSCA) Inventory of Chemicals. It is not confirmed as a carcinogen but is considered a suspect carcinogen. The recommended exposure limits are OSHA PEL 50 ppm, ACGIH TLV 50 ppm. For higher concentrations,... 

A useful application in the manufacture of ion-exchange resins may well be possible which avoids the use of carcinogenic chloromethyl ether. Here, a polymer of p-methyl styrene is chlorinated on the side chain with aqueous NaOCl and a phase-transfer catalyst. Sasson et al. (1986) have shown how stubborn . substituted aromatics like nitro/chlorotoluenes can be oxidized to the corresponding acids by using aqueous NaOCl containing Ru based catalyst. 

IARC. 1979. Acrylonitrile, acrylic and modacrylic fibres, and acrylonitrile-butadiene-styrene and styrene-acrylonitrile copolymers. IARC monographs on the evaluation of the carcinogenic risk of... 

Styrene is a commercially important monomer that is used extensively in the manufacture of polystyrene resins and in co-polymers with acrylonitrile and 1,3-butadiene (reinforced plastics). Exposure to styrene occurs due to intake of food that has been in contact with styrene-containing polymers. lARC has determined that styrene is possibly carcinogenic to humans. There is no restriction on using styrene within the European Union (i.e., there is no SML). 

The lARC has determined that there is limited evidence in experimental animals and in humans for the carcinogenicity of styrene. ... 

Toxicology. Styrene oxide is a skin and eye irritant and may produce skin sensitization it is carcinogenic in experimental animals. 

The lARC has determined that there is sufficient evidence for the carcinogenicity of styrene oxide to experimental animals and that, although there is inadequate evidence for the carcinogenicity to humans, it should be regarded as probably carcinogenic to humans. The ACGIH has not determined a threshold limit value (TLV) for styrene oxide. 

Ponomarkov M Cabral JRP, Wahrendorg J, et al A carcinogenicity study of styrene-7,8-oxide in rats. Cancer Lett 24 95-101, 1984... 

Since the monomers are carcinogenic, should the polymerization of styrene, acrylonitrile, and vinyl chloride be banned ... 

A. Agent is probably a human carcinogen Limited human data Sufficient animal data PCBs, styrene oxide... 

B. Agent is possibly a human carcinogen Limited or inadequate human data Sufficient animal data Styrene, TCDD... 

Effects of styrene on human health depend on concentration, length of exposure, and individual genetics. Styrene vapor irritates the eyes, the nose, and the throat and can adversely affect the central nervous system. Health effects associated with breathing low concentrations of styrene over extended periods in the workplace include alterations in vision and hearing loss and increased reaction times. The Environmental Protection Agency has classified styrene as a potential human carcinogen. 

An example of this type of a safer chemical is methacrylonitrile (1) compared with acrylonitrile (2) (Figure 1.1). Both compounds are a, 3-unsaturated aliphatic nitriles, and structurally very similar, but 2 causes cancer whereas 1 does not appear to do so. Among other applications, 2 is used in the production of acrylic and modacrylic fibers, elastomers, acrylonitrile-butadiene-styrene and styrene-acrylonitrile resins, nitrile rubbers, and gas barrier resins. In a study conducted by the US National Toxicology Program (NTP) in which 2 was administered orally to mice for 2 years, there was clear evidence that it caused cancer in the treated mice (in addition to causing other toxic effects), and is classified by the NTP as a probable human carcinogen [26]. 

Air qualify and plant effluent have been monitored and more or less regulated from the inception of SBR manufacture. Most local and state governments have stncl discharge permits that limit what kind of chemicals and how much of it can be emitted into die environment. Both styrene and butadiene are considered suspect carcinogens,... 

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