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Naphthalene poisoning (or mothball poisoning) is a form of poisoning that occurs when naphthalene is ingested. Severe poisoning can result in haemolytic anaemia. [citation needed] Naphthalene was introduced in 1841 by Rossbach as an antiseptic to counteract typhoid fever. Although naphthalene was widely used industrially, only nine cases of ...
Naphthalene and its alkyl homologs are the major constituents of creosote. Trace amounts of naphthalene are produced by magnolias and some species of deer, as well as the Formosan subterranean termite, possibly produced by the termite as a repellant against "ants, poisonous fungi and nematode worms". [28]
Both naphthalene and 1,4-dichlorobenzene undergo sublimation, meaning that they transition from a solid state directly into a gas; this gas is toxic to moths and moth larvae. [1] Due to the health risks of 1,4-dichlorobenzene, and flammability of naphthalene, other substances like camphor are sometimes used.
Many gases have toxic properties, which are often assessed using the LC 50 (median lethal concentration) measure. In the United States, many of these gases have been assigned an NFPA 704 health rating of 4 (may be fatal) or 3 (may cause serious or permanent injury), and/or exposure limits (TLV, TWA/PEL, STEL, or REL) determined by the ACGIH professional association.
The chemicals composing the block vary. The original formulations were based upon naphthalene and then later para-dichlorobenzene, both now known to be hazardous to health by inhalation. In some areas, the use of para-dichlorobenzene-based blocks has been banned; in other areas para-dichlorobenzene blocks or "para blocks" are still used.
One of the most toxic compounds known, 2,3,7,8-tetrachlorodibenzo[p]dioxin, a PCDD, is assigned a TEF of 1. [54] In June 2020, State Impact of Pennsylvania stated that "In 1979, the EPA banned the use of PCBs, but they still exist in some products produced before 1979. They persist in the environment because they bind to sediments and soils.
It is considered to be only slightly toxic but when at higher concentrations it can be toxic to animals. This was shown when tested on rats via oral ingestion at 1000–5900 mg/kg. [ 3 ] NAA has been shown to greatly increase cellulose fiber formation in plants when paired with another phytohormone called gibberellic acid.
Naphtha (/ ˈ n æ f θ ə /, recorded as less common or nonstandard [1] in all dictionaries: / ˈ n æ p θ ə /) is a flammable liquid hydrocarbon mixture.Generally, it is a fraction of crude oil, but it can also be produced from natural-gas condensates, petroleum distillates, and the fractional distillation of coal tar and peat.