Paint toxicity

TJ. Lennox, M.R Peterson, and RE Groover, Corrosion of Aluminum Alloys by Antifouling Paint Toxicants and Meets of (Tathodic Protection, Paper 16, presented at NAC (Tonference, Qeveland, OR National Association of Corrosion Engineers, 1968... 

CH2CI2. A colourless liquid with a chloroform-like odour b.p. 4I°C. Prepared by heating chloroform with zinc, alcohol and hydrochloric acid manufactured by the direct chlorination of methane. Decomposed by water at 200°C to give methanoic and hydrochloric acids. Largely used as a solvent for polar and non-polar substances, particularly for paint removal (30%), dissolving cellulose acetate and degreasing (10%). It is more stable than carbon tetrachloride or chloroform especially towards moisture or alkali. It is somewhat toxic. U.S. production 1981 280000 tonnes. 

PbEu (anti-knock agents), radiation and sound shields, in paints, high quality glass. World production 1980 4 0 megatonnes. Lead compounds are toxic and hazardous to health. 

One of the chief uses of chloromethane is as a starting material from which sili cone polymers are made Dichloromethane is widely used as a paint stripper Trichloromethane was once used as an inhalation anesthetic but its toxicity caused it to be replaced by safer materials many years ago Tetrachloromethane is the starting mate rial for the preparation of several chlorofluorocarbons (CFCs) at one time widely used as refrigerant gases Most of the world s industrialized nations have agreed to phase out all uses of CFCs because these compounds have been implicated m atmospheric processes that degrade the Earth s ozone layer... 

Uses. Tetrahydrofurfuryl alcohol is of interest in chemical and related industries where low toxicity and minimal environmental impact are important (134). For many years tetrahydrofurfuryl alcohol has been used as a specialty organic solvent. The fastest growing appHcations are in formulations for cleaners (135) and paint strippers (136), often as a replacement for chlorinated solvents (137). Other major appHcations include formulations for crop sprays, water-based paints, and the dyeing and finishing of textiles and leathers. Tetrahydrofurfuryl alcohol also finds appHcation as an intermediate in pharmaceutical appHcations. 

The alimentary symptoms may be overshadowed by neuromuscular dysfunction, accompanied by signs of motor weakness that may progress to paralysis of the exterior muscles or the wrist (wrist drop), and less often, of the ankles (foot drop). Encephalopathy, the most serious result of lead poisoning, frequendy occurs in children as a result of pica, ie, ingestion of inorganic lead compounds in paint chips this rarely occurs in adults. Nephropathy has also been associated with chronic lead poisoning (147). The toxic effects of lead may be most pronounced on the developing fetus. Consequendy, women must be particulady cautious of lead exposure (148). The U.S. Center for Disease Control recommends a blood level of less than 10 p.m per 100 mL for children. 

AppHcations of mercury include use in batteries (qv), chlorine and caustic soda manufacture (see Alkali and chlorine products), pigments (see Pigments, inorganic), light switches, electric lighting, thermostats, dental repair (see Dental materials), and preservative formulations for paints (qv) (1—3). As of the end of the twentieth century, however, increased awareness of and concern for mercury toxicity has resulted in both voluntary and regulatory reduction of mercury usage (see also Mercury compounds). 

Prior to the 1990s phenyhnercuric acetate was the primary bactericide and fungicide in latex and waterborne paints. Because of the increasing concerns of mercury toxicity and the potential for high consumer and occupational exposures to mercury when present in paints, the U.S. Environmental Protection Agency (EPA) induced U.S. manufacturers of PMA and other mercury compounds to withdraw their registrations for use of these substances as biocides in paints (see AIercury). Mercury compounds are used only for very limited, specific purposes, such as the use of phenyhnercuric mXx.2LX.e[55-68-5] as a bactericide in cosmetic eye preparations (see Cosmetics). 

Coatings, Paints, and Pigments. Various slightly soluble molybdates, such as those of zinc, calcium, and strontium, provide long-term corrosion control as undercoatings on ferrous metals (90—92). The mechanism of action presumably involves the slow release of molybdate ion, which forms an insoluble ferric molybdate protective layer. This layer is insoluble in neutral or basic solution. A primary impetus for the use of molybdenum, generally in place of chromium, is the lower toxicity of the molybdenum compound. 

Environmental Impact of Ambient Ozone. Ozone can be toxic to plants, animals, and fish. The lethal dose, LD q, for albino mice is 3.8 ppmv for a 4-h exposure (156) the 96-h LC q for striped bass, channel catfish, and rainbow trout is 80, 30, and 9.3 ppb, respectively. Small, natural, and anthropogenic atmospheric ozone concentrations can increase the weathering and aging of materials such as plastics, paint, textiles, and mbber. For example, mbber is degraded by reaction of ozone with carbon—carbon double bonds of the mbber polymer, requiring the addition of aromatic amines as ozone scavengers (see Antioxidants Antiozonants). An ozone decomposing polymer (noXon) has been developed that destroys ozone in air or water (157). 

Pigments and Extenders. Pigments are selected for use in house paints based on thek appearance and performance quaUties. Appearance includes color and opacifying abiUty. Performance quaUties include ultraviolet light resistance, fade resistance, exterior weatherabiUty, chemical resistance, as well as particle size and shape. Toxicity profiles and safety and health related properties are also important criteria in pigment selection. 

Solvents. Solvents in house paints serve several essential purposes. They keep the binder dispersed or dissolved and the pigments dispersed in an easy-to-use state. Solvents allow the paint to be appHed in the correct thickness and uniformity, and evaporate from the paint film after the paint is apphed. Solvent choice is limited mainly to a solvent that is compatible with the binder system and that has the desked evaporation rate and toxicity profile. The volatility or evaporation rate of a solvent determines to a large extent the open-time and dry-time properties of a paint (6). 

Safety Showers. Safety showers and eyewash fountains or hoses should be installed where corrosive or toxic materials are handled. A large-volume, low velocity discharge from directly overhead should effect continuous drenching, ie, a minimum flow of 20 L/min (50 gal /min). Water to outside showers may be heated to a maximum temperature of 27°C by an electric heating cable. The valves for all safety showers should be at the same height and relative position to the shower head, and they should operate in the same way and direction. The shower station should be identified by paint of a bright, contrasting color. In areas where chemicals harmful to the eyes may be encountered, an eyewash fountain or spray should be available in case of splash accidents. 

The advantages claimed for organotin polymer-based antifouling paints include constant toxicant deHvery vs time, erosion rate and toxicant deHvery are controUable, no depleted paint residue to remove and dispose, 100% utilization of toxicant, polishing at high erosion rates, surface is self-cleaning, and function is continuously reactivated. 

Butyl glycol ethers, the largest volume derivatives of -butyl alcohol used ia solvent appHcations (10), are obtained from the reaction of 1-butanol with ethylene oxide. The most important of these derivatives, 2-butoxyethanol, is used principally ia vinyl and acryHc paints as well as ia lacquers and varnishes. It is also employed ia aqueous cleaners to solubilize organic surfactants. 2-Butoxyethanol [111-76-2] has achieved some growth at the expense of the lower alkoxyethanols (ie, methoxy and ethoxyethanol) because of 2-butoxyethanol s lower toxicity. 

Butyl acetate [123-86-4], one of the more important derivatives of -butyl alcohol produced commercially, is employed as a solvent ia rapid dryiag paints and coatings. In some instances, butyl acetate, has replaced ethoxyethyl acetate [111-15-9] due to the latter s reported toxicity and... 

Inhibited grades of 1,1,1-trichloroethane are used in hundreds of different industrial cleaning appHcations. 1,1,1-Trichloroethane is preferred over trichloroethylene or tetrachloroethylene because of its lower toxicity. Additional advantages of 1,1,1-trichloroethane include optimum solvency, good evaporation rate, and no fire or flash point as determined by standard test methods. Common uses include cleaning of electrical equipment, motors, electronic components and instmments, missile hardware, paint masks, photographic film, printed ckcuit boards, and various metal and certain plastic components during manufacture (see Metal surface treatments). 

J. F. Fabrics and co-workers. Toxicity of Powder Paints by Inhalation, Report No. 1092/RI, Institut National De Recherche Et De SncuritH (INRS), Dept, of Occupational Pathology, France, 1982. 

M. J. Duim, Paint Uamish Prod, 49—51 (Aug. 1973). Toxicity Thorny Problem in Color Manufacturing. A few thoughts on colorant toxicity. 

Because of the toxicity associated with lead compounds, governmental rulings have severely limited the use of lead drier in coatings. From a performance viewpoint the use of lead in aluminum paint will destroy the leafing characteristics of the film. Coatings containing lead that are exposed to sulfur fumes will discolor. 

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