Acrylaldehyde is a colourless to yellowish, flemmable liquid with a disagreeble, choking odour. It is used as an intermediate in the manufacture of synthetic glycerol, polyurethane and polyester resins, pharmaceuticals and herbicides, and as a tear gas. The oral LD50 in rats is 46 mg/kg, and the inhalation LC50 in rats is 750 mg/m³ (10 min of exposure) or 300 mg/m³ (30 min of exposure). Acrylaldehyde is intensely irritating to the eyes and upper respiratory tract. Liver and lungs metabolize this chemical. It is mutagenic in Salmonella typhimurium, produces adducts of bacterial DNA and is clastogenic for DNA of rat hepatocytes. The carcinogenic potential of acrylaldehyde per se has not been adequately determined, but glycidaldehyde, a potential its metabolite is considered to be carcinogenic. Acrylaldehyde is not classifiable as a human carcinogen. The Expert Group recommends a MAC of 0.05 mg/m³ for acrylaldehyde and according to its irritative effects a MAC-STEL of 0.10 mg/m³. Because percutaneous absorption of acrylaldehyde has caused systemic toxicity in laboratory animals, "Sk" notation is considered appropriate. “C” – corrosive notation is also recommended.

Bromine (CAS Register No. 7726-95-6) is a brown or red liquid with a characteristic odour. Bromine is mainly used in the manufacture of dyes, inks, flame retardants, pharmaceuticals and chemical warfare agents. Occupational exposure to bromine may occur during the production and the application of bromine compounds and during other industrial activities. This compound is adsorbed into the human body through the respiratory tract, skin (occupational exposure) and alimentary tract (general population). Slight eye irritation occurs as a consequence of chronic exposure to bromine vapours at concentration of 1 mg/m³. Higher concentrations increase this effect and cause nasal and skin irritation. Many years’ observations have shown that during occupational exposure to bromine vapours at concentrations of up to 0.7 mg/m³ (0.1 ppm), there are no observed adverse effects. Therefore the Expert Group for Chemical Agents has established for bromine an 8-hour TWA value of 0.7 mg/m³. Because of irritation of the respiratory tract after exposure to bromine a STEL value of 1.4 mg/m³ has been established. Considering bromine corrosive properties we suggest additional notation "C".

Bromomethane (BM) is a colourless gas (or liquid in the temperature below 3.56 ⁰C of a characteristic smell similar to that of chloroform. This compound, owing to its biocide properties, has found wide application in agriculture as a pesticide (insecticide, fungicide, herbicide), fumigant during the quarantine of goods (fumigation) and also as a semifinished product of numerous chemical syntheses (a methylating agent).Bromomethane is well absorbed by airways, skin and the digestive tract. This compound (in the form of gas and liquid) demonstrates a strong irritating effect on eyes, airway mucosa and on skin. In local effect on skin due to easy penetration through clothes (it even penetrates through rubber gloves) it may cause second-degree burns or frostbite. The picture of active intoxication with bromomethane in humans is characterized by three basic symptoms: pulmonary oedema, circulatory failure and neurological disorders. Lethal intoxication of humans is mainly associated with exposure to high concentrations of the compound (33,000 233,400 mg/m³). Investigating acute inhalatory toxicity of bromomethane demonstrated in all tested animal species pulmonary oedema connected with respiratory failure, pathological changes in organs (lungs, the liver and kidneys) and neurological symptoms (movement coordination dysfunction, seizures and paralysis). In available literature there are no data on bromomethane allergic activity. On the basis of the obtained results on subchronic and chronic toxicity in rats and mice exposed through inhalation, bromomethane was demonstrated to affect primarily the following organs: the brain, kidneys, olfactory epithelium, heart, adrenal glands, lungs, liver and gonads (testicles) and to cause neurobehavioural disturbances. The compound has a mutagenic and genotoxic activity both in vitro and in vivo. On the basis of the results concerning the effect of bromomethane on reproduction, embryotoxicity and tetratogenicity, bromomethane demonstrates in rats and in mice activity inhibiting spermatogenesis, it causes resorption of rat fetuses and occurrence of congenital defects in rabbits (acystia and lack of lung caudate lobe). Bromomethane is not classified by IARC as a human cancerogen. The results of epidemiological studies (questionnaires) carried out in Japan were accepted as a basis for calculating a MAC value for bromomethane. It results from an analysis of the questionnaires that in workers chronically exposed to bromomethane the following symptoms of irritating effect were observed: skin itching, blisters, swelling and reddening of hands, drying and keratonization of skin and rhinorrhoea. Furthermore, the following symptoms from the nervous system occurred: dementia, stupor, fatigue, numbness, dysaesthesia and muscular weakness of limbs. The bromomethane concentration of 21.39 mg/cm³ was accepted as an LOAEL value and applying proper uncertainty coefficients, bromomethane TWA value was suggested to be 5 mg/m³ and, due to the compound irritating activity, a STEL value to be 15 mg/m³.

1,4-Dioxane is a highly flammable liquid with etheric odour. This compound is used, among other, as a solvent in the production of lacquers, varnishes, cleaning and detergent preparations, adhesives, cosmetics, extraction media for animal and vegetable oil. At present exposure to this chemical is rather low. Acute toxicity of 1,4-dioxane for laboratory animals is low. The liver, kidneys, mucous membrane of respiratory tract and eyes are critical organs in animals repeatedly exposed to 1,4-dioxane. No mutagenic, genotoxic, and teratogenic effects have been found in relevant experimental studies. Liver and nasal adenomas and carcinomas were seen in rats and mice after oral administration of 1,4-dioxane. The MAC (TWA) value was calculated on the basis of the LOAEL value (180 mg/m³) for irritation of the eye in volunteers and of the NOAEL value (400 mg/m³) for systemic toxic effects in rats.The MAC (TWA) value at the level of 50 mg/m³ was proposed. There is no evidence justifying a proposal of a MAC-STEL value.

Ethylamine (CAS number: 75-04-7), (synonym: aminoethane) is a colorless, flammable liquid or gas, depending on the ambient temperature, with an ammonia-like odor. Ethylamine is a dangerous fire hazard. Ethylamine is used in solvent extraction; organic synthesis; as a dye intermediate; as a stabilizer for rubber latex; in petroleum refining; and in the manufacture of detergents, photographic dyes, emulsifying agents, and medicinal products. Ethylamine is irritating to both the skin and eyes of test animals. The oral LD₅₀ in rats is 400 mg/kg and the dermal LD₅₀ in rabbits is 390 mg/kg. The RD₅₀ (concentration producing a 50% decrease in respiration rate) in mice was 278 mg/m³ (151 ppm). Rabbits exposed 7 hours/day, 5 days/week for 6 weeks at 90 mg/m³ (50 ppm) ethylamine experienced irritation of the lungs and eyes. The lung lesions included peribronchitis and pneumonitis with thickening of small blood vessels. The ocular changes involved multiple epithelial erosions and edema of the cornea. Focal muscular degeneration of the heart was seen in some rabbits. Corneal and heart changes were not seen at 180 mg/m³ (100 ppm); however, the kidneys of this group showed slight to moderate parenchymatous degeneration. Rats exposed 6 hours/day, 5 days/week for 24 weeks at 18 mg/m³ or 180 mg/m³ (10 or 100 ppm) showed no adverse effects. In the same study, at 900 mg/m³ (500 ppm), body weight gains were reduced and inflammatory necrosis and squamous metaplasia were seen in the anterior portions of the nose. Eye irritation and corneal edema have been reported from ethylamine exposure in industry but concentrations of ethylamine have been unknown. Based on the RD₅₀ value of ethylamine MAC–TWA of 9.4 mg/m³ and MAC-STEL of 18 mg/m³ are recommended to minimize the potential risk of irritation. Skin notation is proposed because of dermal LD₅₀ in rabbits ∠ 1000 mg/kg. Notation "I" - irritating substance is recommended.

Phosphine is a colorless and odorless gas in the pure state, whereas technical phosphine has a garlic-like odor. It is soluble in ethyl alcohol, ether and water. Phosphine is used as a fumigant, in chemical synthesis of organo- phosphines and organic phosphonium derivatives. The 4-hour LC₅₀ for phosphine in rats is 15 mg/m³. Acute exposure to phosphine produces similar effects in man and animals. Signs of inhalation exposure are typical of respiratory irritation. Concentrations of ca. 200 mg/m³ produce serious effects after 0.5 – 1 h, but 10 mg/m³ has no serious effects. The predominant pathological fea-ture in acute fatal cases is pulmonary oedema. Neurological abnormalities include headache, tremors, coma, and death. Gastrointestinal symptoms include loss of appetite, nausea, vomiting, diarrhea and jaundice. Phosphine at a concentration of 7 mg/m³, 4 h/day is tolerated by laboratory animals for 2 month. There are no cumulative effects. It is not a teratogenic or carcinogenic agent. The Expert Group has recommended the value of 0.14 mg/m³ as the MAC value and 0.28 mg/m³ as MAC-STEL. It has also recommended the "I" (irritant agent) notation.

Isooctyl alcohol is a flammable, colorless liquid with a light odor. This chemical is a mixture of isomers, mainly dimethylhexan-1-ol and methylheptan-1-ol. After single or repeated inhalation exposure the main effect is local irritation. Based on the NOAEL value obtained from experiment on rats (1064 mg³) a MAC value of 220 mg/m³ was established. Because of the irritant effect of this compound a MAC-STEL value 440 mg/m³ was suggested. The "I" (irritating substance) notation and "Sk" (substance absorbed through the skin) were proposed.

Naphthalene is a white, crystalline powder with a characteristic odor. It is insoluble in water, slightly soluble in methanol, ethanol, and soluble in benzene, ether and chloroform. Naphthalene is widely used in industrial processes. It is used in the manufacture of dyes, naphthols, and as a moth repellent, as a preservative, a disinfectant, and an illuminant. Inhaled naphthalene fumes produce visual disturbances, headache, nausea, and vomiting. Naphthalene may be acutely irritant to eyes and the respiratory tract. Oral intoxication in industry is unlikely. Naphthalene is rapidly absorbed by the human body when inhaled, but slowly by skin and by ingestion. Experiments in the rat showed that naphthalene was readily converted to 1- or 2-naphthol and 1,2-dihydro-1,2-naphthalenediol, and excreted free or as 1- or 2-hydroxyglucuronide or 1-sulfate. Naphthalene was negative for the induction of gene mutations in Salmonella typhimurium, induced sister chromatid exchanges in a test with Chinese hamster ovary cells. Under the conditions of these 2-year inhalation studies there was no evidence of carcinogenic activity of naphthalene in male B6C3F1 mice exposed to 10 or 30 ppm (50 and 150 mg/m³). There was some evidence of carcinogenic activity in female B6C3F1 mice, based on increased instances of pulmonary alveolar/bronchiolar adenomas. The Expert Group recommends a MAC of 20 mg/m³ for naphthalene and – according to its irritative effects –MAC-STEL of 50 mg/m³. Because percutaneous absorption of naphthalene has caused systemic toxicity, the "Sk" notation is considered appropriate. The "I" - irritation notation is also recommended.

Turpentine is a general term for crude oleoresin obtained from soft wood conifers. Turpentine is a mixture of substances, mostly terpenes (58%.65). Terpenes are an ubiquitous group of natural compounds, with over 4000 identified, derived from units of isoprene (2-methyl-1,3-butadiene). Major components of turpentine are α-pinene, β-pinene, Δ3-carene, which are bicyclic monoterpenes with the molecular formula of C10H16. Turpentine is a by-product in the paper and pulp industry. Terpene vapors are also released with the dust during the process of sawing and treating timber and boards.Turpentine was formerly the most widely used paint thin-ner. It is also used as a solvent for various resins, polishes, and waxes. Turpentine is used in veterinary practice as an expectorant, rubifacient, and antiseptic, owing to its anti-microbial properties. Turpentine is increasingly being used as a raw material for making chemicals; turpentine and its monoterpenes are employed in liniments, perfumery, and in the synthesis of camphor and menthol. LC50 values for turpentine vapor in rats of 20,104 mg/m³ for 1-hour exposure and 12,040 mg/m³ for 6-hour ex-posure have been established. Signs of acute turpentine intoxication included ataxia, tremor, convulsions, tachypnea, decreased tidal volume, and death due to sudden apnea. Turpentine has an RD50 of 7560 mg/m³. Turpentine is a skin and mucous membrane irritant and sensitiser, and in high concentrations, a CNS depressant. Various chamber studies in healthy volunteers have shown that there is significant reporting of eye, nose, and throat irritation from turpentine, pinenes and Δ3-carene for 2 hour exposures with light exercise at 450 mg/m³, as well as an increase of airway resistance. In occupational exposure study with healthy volunteers, it has been found that TLco and alveolar volume decrease after exposure. This study showed that healthy volunteers ex-posed to sawmill air contaminants experienced an acute inflammatory reaction in the upper airways. In occupational studies, the association between exposure to terpenes and acute effects on lung function with personal exposures ranging from 11 to 158 mg/m³ of terpenes has been evaluated. A significant decrease in the carbon monoxide lung diffusing capacity was identified. In setting exposure limits, chamber studies were considered. Based on the NOAEL value of 225 mg/m³ and the relevant uncertainty factors, a MAC (TWA) value was calculated at 112 mg/m³ for turpentine to minimize the potential for upper respiratory tract irritation. MAC (STEL) value of 300 mg/m³ is recommended. Notations "I" (irritating substance) and "A" (sensitising substance)are recommended.

Carbon tetrachloride (CCl₄) is a colorless, clear, nonflammable liquid with a characteristic ether-like odor. It may decompose upon heating to produce corrosive and toxic gases. Due to its toxic properties CCl4 is no longer used as a solvent. Liver is the target organ for carbon tetrachloride toxicity. Slight cirrhosis and fatty infiltration of the liver occurred as a result of chronic inhalation exposure (187 days, 134 days of exposure) of rats to 320 mg/m³ of carbon tetrachloride. NOAEL amounted to 160 mg/m³. CCl4 toxicity is due to biotransformation of the solvent into a free radical (•CCl3) and other reactive metabolites by the hepatic cytochrome P-450 system and, particularly, by P4502E1. The toxicity of carbon tetrachloride is increased by alcohol ingestion. Carbon tetrachloride was classified by IARC as possibly carcinogenic to humans (Group 2B). Results of animal experiments suggested a common biological mechanism, cell death and regeneration. CCl¬4 is not genotoxic. Inhalation unit risk amounts to 1.5 E-5. There is evidence that CCl4 is fetotoxic but not teratogenic. Based on the NOAEL value from an inhalation study in rats a TWA value of 20 mg/m³ was proposed. There are no bases for establishing OEL (STEL) or BEI values. The substance can be absorbed through skin.