Antimony oxides toxicity

The self-ignition temperature of PVF film is 390°C. The limiting oxygen iadex (LOI) for PVF is 22.6% (98), which can be raised to 30% ia antimony oxide-modified film (99). Hydrogen fluoride and a mixture of aromatic and aUphatic hydrocarbons (100) are generated from the thermal degradation of PVF. Toxicity studies, ie, survival and time to iacapacitation, of polymers, ceUulosics (101,102), and airplane iaterior materials (103) expose... 

M One-Year Inhalation Toxicity Study ofMntimonj Trioxide in the Rat (with a One-year Recovery Period), Bio /dynamics Incorporated, East Millstone, N.J. submitted to Antimony Oxide Industry Association (AOIA), Feb. 9, 1990. 

Low Toxicity - Unlike antimony oxide, the zinc borate is considered non-toxic. 

Prudence requires that all antimony compounds should be treated with caution and, until proved otherwise, be considered toxic. While it is true that some studies have shown that, in the short term, antimony oxides may be considered non-hazardous, in the longer term they... 

Environment, toxicity With durable flame retardancy, formaldehyde emission during curing and after finishing, phosphorous compounds in the waste water Antimony oxide and organic halogen donators (DBDPO and HCBC) are discussed as problems (for example possibility of generating polyhalo-genated dioxins and furanes)... 

Health issues can be related not only to the pyrolysis products of the polymer itself, but also may be related to the compounds that come from the polymer additives. For example, in a study of pyrolysis of high impact polystyrene with decabromodiphenyi ether/antimony oxide added as a flame retardant, it has been shown that toxic polybrominated dibenzofuranes are generated during thermal decomposition in the range of 350-400° C [15]. 

Although other fining agents are usually less efficient, the toxicity of arsenic and antimony oxides often force the use of other approaches to chemical fining. Sodium sulfate, for example, also serves as a source of... 

With the exception of alumina hydroxides, fire-retardant phosphorus compounds are now used in greater quantities than any of the other main types of retardants, that is, antimony oxide, borates or halogenated hydrocarbons. Advantages claimed for organophosphorus-based fire retardants are relatively low toxicity and minimum harmful volatiles under burning conditions [37]. 

The materials chosen to perform these functions must not interfere with the final product s properties, the usefulness of the product, safety, or other environmental and toxicity requiranents. It is common to formulate plastics with multiple flame retardants, typically a primary flame retardant plus a synergist such as antimony oxide, to enhance overall flame retardant efficiency at the lowest cost. Several hundred different flame retardant systems are used by the plastics industry because of these formulation practices. 

Decabromodiphenyl ether is a solid, melting at about 304-309°C, substantially insoluble in water, and with negligible vapor pressure. In contrast to the lower brominated diphenyl ethers, it has only rarely been found as an environmental pollutant and is low in toxicity. Risk studies conducted in the United States and the European Union (33,35) indicate a low degree of risk in the use of this flame retardant. It is the major flame retardant used in high impact polyst5Tene (HIPS) with antimony oxide, and has substantial use in polyolefin wire and cable as well as electrical parts made of other plastics such as polyamides and thermoplastic polyesters. 

Fillers may promote char magnesium hydroxide, zinc borate, antimony oxides require high loadings and can degrade mechanical and other properties. Toxicity of antimony-based retardants is a concern. Can be used with other flame retardants synergistically. 

Smoke suppressants are also important additives in fire retardance. Visible smoke may accompany or precede the development of heat and toxic gases. It results from an incomplete combustion. Additives such as antimony oxide, metal (Ba, Ca, Zn) borates, A1(0H)3, Mg(OH)2, MgC03, and magnesium oxychloride are used as fillers and flame retardants, but they are also good smoke reducers. 

Halogen-based FR are special chemicals. They are required to be relatively noncorrosive, low toxicity, and yet, liberate corrosive halogen compounds that react with antimony oxide at fire temperatures. Some of these chemicals have chemistry similar to PVC and, thus, sometimes they require thermal stabilizers to withstand thermal processing. 

About 120 thousand tons of antimony and antimony oxide was giobaiiy produced in 2012. It was used mainly by the rubber, plastics, textile, leather, and coatings industries as a flame retardant. Even though antimony oxide is toxic, it continues to be used. 

In some cases it is difficult to replace antimony oxide because it is such an eifective flame retardant. However, because of its high toxicity, there have been many cases where such additives as alumina trihydrate have been used in place of antimony oxide. 

There is continued concern about the use of antimony oxide because of its toxicity. This increased concern might affect supply in the future. 

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