Naphtha toxicity

Clark DB, Butterworth ST, Martin JG, et al. 1989. Inhalation toxicity of high flash aromatic naphtha. Toxic Ind Health 5(3) 415-428. 

McKee RH, Wong ZA, Schmitt S, et al The reproductive and developmental toxicity of high flash aromatic naphtha. Toxicol Ind Health 6 441M60, 1990... 

Carpenter CP, Kinkead ER, Geary KL, et al Petroleum hydrocarbon toxicity series. II. Animal and human response to vapors of varnish makers and printers naphtha. Toxicol Appl Pharmacol 32(2) 263-281, 1975... 

Toxicity tests on 31 pure hydrocarbons of aromatic, olefin, naphthene, and paraffin series are reported. The hydrocarbons, ranging in boiling point from 176 to 572 F., were representative of those found in petroleum naphthas. The work was done at Ithaca, N. Y., in both greenhouse and field plots. 

When the toxicity evaluations in Table I are compared with those in Figure 1, the two methods of evaluation agree very well. It would not be safe to assume that the selective concentrations in Figure 1 provide exact measurements of the phytotoxicities of the hydrocarbons. It is believed, however, that they do give a close approximation of their relative toxicities as they occur in petroleum naphthas. 

The most toxic hydrocarbons, tetrahydronaphthalene, methylnaphthalene, diphenyl-methane, and dimethylnaphthalene, had selective concentrations below 15%. Petroleum naphthas which contain these hydrocarbons even in relatively small amoimts would be very toxic to plants. 

There was some indication that the presence of nontoxic oil in the emulsion caused a tendency toward selectivity. For example, a 10% emulsion of either methylnaphthalene or dimethylnaphthalene killed the greenhouse test plants with no selectivity. The addition of 20% nontoxic oil, however, greatly reduced the carrot injury without an apparent reduction in toxicity to the other species. Tests were conducted with water emulsions of highly phytotoxic naphthas which contained 75 to 85% aromatics and had boiling ranges of to 550 F. Excellent selectivity was obtained in some tests, but in other tests the emulsion gave severe injury to carrots. The results with emulsions of high aromatic naphthas were inconclusive. 

Human exposure to ethylbenzene occms mainly via inhalation of vapour and/or mist and, to a smaller extent, by dermal contact or ingestion. Ethylbenzene is produced by the incomplete combustion of natural materials, making it a component of smoke from forest fires and cigarettes. It is also a constituent of asphalt and naphtha (Agency for Toxic Substances and Disease Registry, 1997a WHO, 1996a). 

Note Polar solvent soluble in water, alcohols (organic halides), ether, and many oils flammable moderately toxic by inhalation and skin absorption incompatible with strong oxidizers, nitrates, strong alkalis, strong acids. Synonyms acedin, acetic ether, acetic ester, ethyl ethanoate, vinegar naphtha, acetic acid ethyl ester. 

Naphthas are used in the rubber industry for dampening the play and tread stocks of automobile tires during manufacture to obtain better adhesion between the units of the tire. They are also consumed extensively in making rubber cements (adhesives) or are employed in the fabrication of rubberized cloth, hot-water bottles, bathing caps, gloves, overshoes, and toys. These cements are solutions of rubber and were formerly made with benzene, but petroleum naphtha is now preferred because of its less toxic character. 

Toxic effects of chemicals can range from mild and reversible (e.g., headache from inhaling petroleum naphtha vapors that disappears with fresh air) to serious and irreversible (e.g., liver or kidney damage from excessive exposures to chlorinated solvents). Toxic effects from chemical exposure depend on the severity of the exposures. Greater exposure and repeated exposure generally lead to more severe effects. 

Occupational standards for JP-8 are primarily based on knowledge about the toxicity of kerosene and naphtha (a petroleum distillate fraction). National Institute for Occupational Safety and Health (NIOSH) guidelines include an 8-hour (hr) time-weighted-average recommended exposure limit (TWA-REL) for naphtha of 400 milligrams per cubic meter (mg/m3) (100 parts per million (ppm)) (NIOSH... 

In the Middle East, where petroleum is abundant, naphtha (the volatile and toxic light fraction of oil) was ignited and poured on attackers. The ancient Indians and Chinese added fire chemicals to their incendiaries, explosive saltpeter or nitrite salts, a key ingredient of gunpowder, and they also mixed a great variety of plant, animal, and mineral poisons, such as arsenic and lead, in smoke and fire bombs. In the New World and in India, the seeds of toxic plants and hot peppers were burned to rout attackers. 

Although the toxicity of Stoddard solvent is not attributable to any one type of constituent, the aromatic components are considered to be more toxic than the paraffin or naphtha/naphthene components. Solvents tend to cause a nonspecific narcosis. This is generally believed to be due to the disrupting (or solublizing) effect that the solvent has on cellular membranes, particularly those of the nervous system. 

Halder CA, Warne TM, Hatoum NS. 1984. Renal toxicity of gasoline and related petroleum naphthas in male rats. Adv Mod Environ Toxicol 7 73-88. 

Exposures to low levels of pesticides are those that occur when toxic effects are observed following inhalation, ingestion, or dermal absorption of concentrations not known to be toxic. An example is the exposure to a commercial formulation of a bifenthrin-containing (8.15) insecticide that was shown to be neurotoxic at levels 3-4 orders of magnitude lower than the NOEL for bifenthrin alone J34l Other chemicals contained in the commercial formula include a surfactant, heavy petroleum naphtha (5.0-6.5) and aromatic petroleum distillate (5.0-7.0). 

Low levels of an applied herbicide-pesticide-solvent mix were drawn into the uptake air of a commercial building following the application of a pesticide mix to the lawn in front of that building. Several employees immediately reported CNS and respiratory symptoms, with one sustaining a permanent respiratory injury. The pesticide mix applied to the lawn was composed of 2,4-D (2.82), 2-(2-methyl-4-chlorophenoxy) propionic acid (MCPP 2.48), and dicamba (2.21). The mixture also contained solvent naphtha (a mixture of aliphatic solvents, Kqw = 3.5-5.0) with 14% naphthalene (2.48) and dinitroaniline (3.30). The concentrations of all pesticides and solvents were far below the TLVs both outside and inside the building. The toxic effects observed were ascribed to the mixture of lipophilic and hydrophilic pesticides. 441... 

Properties Thick, viscous, oily liquid affected by air and light. Soluble in solvent naphtha. Hazard Toxic by ingestion. 

Mineral spirits — Flammable petroleum distillates that boil at temperatures lower than kerosene and are used as solvents and thinners, especially in paints and varnishes. Mineral spirits are the common term for some naphthas. Mineral spirits were used extensively in chemical dispersants made before 1970 but are no longer used due to their toxicity. (See also Naphtha.)... 

Orthorhombic cryst mass or flakes fatty appearance, bp 247 d 3.95. Sol in water, ethanol, acetone, ether, methyl acetate, methyl ethyl ketone, isobutyl alcohol practically insol in mineral spirits, pstr naphtha, xylene. LDW i.p. in mice 66 mg/kg. Toxic Substances List, H. E. Christensen ei al. Eds. (1974) p 765. 

API. 1987a. Acute inhalation toxicity evaluation of a petroleum derived hydrocarbon in rats - API 84-02 and API 85-01 with heavy thermal cracked naphtha, with cover letter dated 05/19/87. Project no. 22235-14. Washington, DC. American Petroleum Institute. 

McKee RH, Hinz JP. 1987. Evaluation of the subacute and subchronic toxicity of inhaled hydrotreated naphtha in the rat. Fundam AppI Toxicol 9 120-130. 

McKee RH, Hinz JP, Traul KA. 1986. Evaluation of the teratogenic potential and reproductive toxicity of coal-derived naphtha. Toxicol AppI Pharmacol 84 149-158. 

Vaziri ND, Smith PJ, Wilson A. 1980. Toxicity with intravenous injection of naphtha in man. Clin Toxicol 16 335-343. 

No systemic toxicity, low viscosity Gasoline, kerosene, petroleum naphtha, mineral seal oil, petroleum ether Low High Observe for pneumonia do not empty stomach. 

Petroleum distillates (petroleum naphtha, petroleum ether) Vapors irritating to eyes and respiratory tract. A CNS depressant. If n-hexane, benzene, or other toxic contaminants are present, those hazards should be addressed. See also p 219. 1100 ppm [LEL] 1 4 0 (petroleum ether) Colorless liquid. Kerosene-like odor at levels below the TLV serves as a warning property. Highly flammable. Vapor pressure Is about 40 mm Hg at 20°C (68°F). 

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