Kerosene

KEROSENE (from Greek keros- wax) has great sanitary significance as the most common illuminating material. In sanitary supervision practice, questions may arise about the admissibility of a given grade of K. for lighting (poor grades burn dimly and strongly spoil the air with products of incomplete combustion), as well as about the possibility and causes of its explosion. Therefore, certain sanitary requirements are imposed on K. K. is a transparent, slightly yellowish liquid with a bluish fluorescence and a peculiar, fairly strong odor; average specific gravity 0.820; it is obtained from petroleum (see.) by fractional distillation and consists of a mixture of various hydrocarbons having a boiling point between 150° and 300°. The composition and properties of K. vary depending on the petroleum from which it is obtained, on the construction of the distillation apparatus, on the admixture of distillates with low and high boiling points, and on the degree of subsequent purification. The main mass of the widely distributed Caucasian kerosene consists of unsaturated hydrocarbons of the CnHn series, so-called naphthenes; in significantly smaller quantities, saturated hydrocarbons of the C_nH_{2I1 + a} series and some random admixtures from petroleum are contained. In American and Galician K., saturated hydrocarbons predominate. The smaller the fluctuations in temperature during the production of a kerosene distillate from petroleum, the more uniform its composition is. However, perfectly homogeneous distillates are usually not obtained during factory distillation of petroleum, because at the temperature of the kerosene fraction, not only hydrocarbons boiling at this temperature distill from the petroleum, but also those boiling at higher temperatures evaporate and pass into the distillate; in addition, the same distillate also receives partly light, low-boiling hydrocarbons, which did not have time to evaporate during the preceding distillation of gasoline from the same petroleum. Therefore, in addition to hydrocarbons boiling at 150-300°, K. always contains in greater or lesser quantities hydrocarbons with higher and lower boiling points. It is often the case that such hydrocarbons are intentionally admixed to kerosene to increase its yield from petroleum. Thus, a kerosene distillate with a specific gravity of 0.8X0 is often mixed with light distillates with a specific gravity of 0.740-0.819 and with heavier distillates with a specific gravity of more than 0.820. As a result, a mixture is obtained having the specific gravity and consistency of ordinary K. Such grades of K. possess significantly greater fire-hazard properties than K. which does not contain admixtures of light hydrocarbons. The normal yield of K. from petroleum of various origins can be seen from the following data. Petroleum from Baku gives 25-30% K. during distillation, Galician petroleum gives 30-40%, Pennsylvania petroleum gives 55-75%, Ohio petroleum gives 30-40%. The kerosene distillate obtained from petroleum is subjected to chemical purification, because it contains foreign admixtures, which give K. an unpleasant odor and the property of quickly resinifying in air and acquiring a brown color in the process. Purification consists in treating the kerosene distillate first with strong sulfuric acid, then with a 25-30% solution of caustic soda, and finally in washing with water. Sulfuric acid sulfates, oxidizes, resinifies, and dissolves the admixtures. Caustic soda neutralizes acids and also extracts phenols, resinous substances, and partly sulfur compounds. During subsequent washing with water, the remaining caustic soda, soda salts, petroleum soaps, etc. are removed from K. The loss during purification amounts to 3-6% of the total amount of kerosene distillate. After purification, K. must be transparent, colorless or have a slightly yellowish color with a bluish fluorescence; the odor must not be sharp. K. finds its greatest application for lighting purposes, as well as for heating portable kitchen stoves—"kerosinok"; in industry it is widely used as a fuel material for kerosene engines. If K. is well purified, then with abundant access of air it burns completely into CO₂ and water, giving no by-products of combustion. If access of air is insufficient, for example due to poor design of the burner (see.), or because the lamp burns with a weak, incomplete flame, a series of products of incomplete combustion are produced, which strongly spoil the air. Especially abundant accumulation of *2Й 61v in the air of volatile hydrocarbons and products of incomplete combustion of K. is observed in poorly ventilated residential and factory premises where many kerosene lamps burn, which are not kept sufficiently clean and poorly serviced. K., poorly purified from foreign admixtures or insufficiently washed from the products of its processing, even with abundant access of air in lamps and kerosene kitchens, pollutes the air with harmful gaseous substances (for example, sulfuric acid). The use of K. as an illuminating material is associated with certain dangers in a fire hazard. Kerosene containing admixtures of low-boiling, very volatile, easily flammable hydrocarbons, such as the hydrocarbons entering the composition of gasoline and gasoline, is especially fire-hazardous. Such K. can cause an explosion of a primus stove, lamp, or kerosene kitchen if an excessively large amount of vapors of volatile hydrocarbons accumulates in the reservoir and they reach extreme tension from overheating, or if an explosive mixture of these vapors with air forms in the lamp reservoir. According to Chandler's experiments, the strongest explosion occurs when 1 part of kerosene vapors is mixed with 8-9 parts of air. A strong explosion also occurs with a ratio of 1:4-5. A mixture of 1 part kerosene vapors and 1 part of air does not explode, but ignites from a burning body at the corresponding temperature. The greatest danger of explosion in kerosene lamps occurs in cases of improper design of the burner, when there is free communication between the gaseous atmosphere of the kerosene reservoir and the burning flame of the lamp. This usually happens if the wick is too narrow and does not completely fill the tube through which it passes from the reservoir to the burner. If a sufficient amount of air penetrates into the lamp reservoir and mixes there with the vapors of light hydrocarbons, then, thanks to the free communication of the reservoir with the flame through the gap, a dangerous explosion of the accumulated gases can occur. This most often happens when extinguishing a lamp by blowing air from above into the lamp glass, or with sharp turns of the flame regulator screw, as well as with careless shaking of the lamp when little K. remains in it. To prevent such explosions and fires and to eliminate abuses with the addition of petroleum gasoline fractions to K., almost all countries have established maximum minimum flash point temperatures of K. vapors by law, which are released from it upon heating in special Abel-Pensky (see. Abel apparatus), Beilstein, and other devices. The higher the flash point temperature of K. vapors, the less low-boiling, very volatile hydrocarbons it contains, the safer it is in terms of fire hazard. The maximum norms established by law for the flash point of K. vapors are different in different countries. RSFSR . . . 28.0° Austria . . 33.0° Hamburg . . 37.0° Germany . 21.0° Zurich . . . S4.0° America . 38.0° England. . .22.8° France . 35.0° Sweden . . 40.0° For Baku K., Mendeleev found it possible, without detriment to its lighting qualities and without special restriction of production, to raise the flash point temperature of vapors to 35.0-40.0°. The temperature of flash point of K. vapors should be distinguished from the temperature of ignition of the K. liquid itself. The temperature of ignition of the K. itself usually lies 5-15° higher than the temperature of flash point of its vapors. To judge the degree of safety of K., it is more important to know the temperature of flash point of vapors than the temperature of ignition of the liquid, since most fires occur from the ignition of vapors. Considering the fire hazard of K., it should not be used for lighting such factory and boiler rooms where the air temperature sometimes reaches 4-5° and above. Storage of large stocks of K. always represents a significant danger in terms of explosion. Kerosene vapors are significantly heavier than air and therefore, collecting at the bottom of premises, can form an explosive mixture near K. storage tanks. A casually lit match, spark, or lightning strike are sufficient for a sudden ignition of such a mixture. Hence the sanitary requirements: warehouses for storing stocks of K., gasoline, gasoline, etc. should be arranged separately from residential buildings, well ventilated, in no case smoke there or light a fire, and enter only with a lamp equipped with a protective grid. It is safest to store large stocks of K. in hermetically sealed underground tanks equipped with a ventilation pipe with a protective grid and pumps for pumping out kerosene. As for accidental and professional poisoning by K., acute poisoning from swallowing K. is observed extremely rarely; in this case the picture of poisoning has great similarity with poisoning by gasoline (see.). Inhalation of large quantities of kerosene vapors causes headaches, dizziness, palpitations, dulling of hearing and smell, then catarrh of the pharynx and bronchi. In chronic cases, in addition to bronchial catarrh, a gradual development of anemia and nervousness is observed.

Literature indicates that inhaling gases emitted by kerosene engines caused workers besides headaches difficulty swallowing, speech disorders, and mild paralysis of the facial nerve. Workers dealing with kerosene often suffer from skin diseases, especially eczema. In medicine, kerosene is used as an external remedy for the treatment of scabies, head lice, etc. In sanitary practice, it is used for disinfection (see), mainly to eradicate bedbugs (in the form of Malinin's liquid), fleas (in the form of soap-kerosene emulsion), fly larvae (pouring kerosene on manure heaps), mosquito larvae (pouring kerosene into water bodies), etc. Labor hygiene questions see Petroleum.

N. Ignatov. Data on the toxicity of kerosene are scanty and contradictory. Some consider kerosene completely harmless. Lewin, based on his observations, believes that kerosene preparations cause pathological phenomena only if taken in large quantities, and all symptoms pass quickly. According to Lewin, irritating action on mucous membranes is possessed especially by those components of kerosene which boil at 250-270°C, and therefore those poor grades of it which are rich in these hydrocarbons. In general, it is considered that ordinary kerosene, which enters the market, well purified by distillation from poisonous, volatile, easily flammable components, is non-toxic and at most can cause nausea. According to Hoffmann, cases of poisoning are also explained by the presence in poorly purified kerosene of volatile hydrocarbons, in particular petroleum ethers (kerosolen, ligroin, etc.). Russian kerosene, containing more substances of the aromatic series, is more toxic than American; Baku kerosene is more poisonous than Caucasian. In forensic-medical practice, kerosene poisoning occurred either as an accident or in attempts at suicide, murder, as well as in the use of kerosene for therapeutic purposes. Sometimes kerosene was administered per os and per vaginam to expel the fetus. In forensic-medical terms, it should also be noted that external application of kerosene in the form of compresses and lotions initially causes irritation, and repeatedly inflammation of the skin with a long-lasting reddish-brown discoloration of the affected areas, and there were cases of intentional use of kerosene in the form of subcutaneous injections to produce artifacts (artificial phlegmons, inflammations, etc.). The lethal dose of kerosene per os for humans is not exactly established; some think it is approximately 7.7 g per 1 kg of body weight. In humans, the intoxicating, narcotic action of kerosene and gastroenteritis symptoms attract attention. In three cases of Poljakov, kerosene was used by women as a therapeutic agent before and during menstruation, then as a laxative and for attacks of gallstone disease; in this case, after doses of 30-85 g per os, all observed were a scratch in the throat, burning along the esophagus, sometimes nausea, slight belching, diarrhea, dizziness, and with repeated intake - intoxication, numbness of limbs, weakness. At autopsy, in cases of death from the introduction of kerosene per os, the following were found: bloody impregnation of the gastric mucosa, hyperemia and swelling of the mucosa of the small and partly large intestines. The lumen of the esophagus is sometimes narrowed, its mucosa is blue-red, strongly swollen. The mucosa of the larynx and windpipe is reddish and slightly edematous, the mucosa of the renal pelves is sharply reddish. The membranes of the brain and its substance are full of blood. In comparing observations of different researchers on animals (rabbits, dogs) with those in humans, similarity is noted both in pre-mortem symptoms and in the pathological-anatomical picture of kerosene poisoning, although some data stand somewhat apart, namely - severe convulsions and paralysis, pneumonia, pericarditis observed in the experiments of some authors, were not encountered in cases of human poisoning and in the experiments of Lewin, Poljakov, etc. In microscopic examination of animal organs, only signs of hyperemia were found. Thus, kerosene is not always harmless, and its toxicity apparently depends on the quality, method of introduction into the body, individual characteristics of the latter and possibly also on other unexplained conditions.