Allergic solvents

Solvent-induced allergies can occur at a variety of working sites, e.g., in shoe factories, in electronic industries, in synthetic chemical industries, in metal industries or in perfume and potter industries (oil of turpentine and other solvents). Similar occurrence of solvents can be found in consumer products, e.g., in nail polishes (e.g., toluene). Allergic solvent substances are listed in various catalogues and databases. 

Examples of allergic solvents are terpene products with high sensitivity potential, which can cause positive test reactions (patch-test) or even allergic diseases (contact sensitization and dermatitis). Allergic dermatitis can even be provoked by d-limonene in the air. Terpenes and terpenoid substances are found especially in natural products , e.g., cosmetic products, foods, and plants (oilseed rape). ... 

Many irritative chemicals may cause non-specific hyper-responsitivity of the airways and skin. The number of irritating chemicals is very large, several thousands. The symptoms caused by exposure to irritants may resemble allergic symptoms. In addition, exposure to irritating substances (such as sulfur dioxide or solvent vapors) often triggers the symptoms in individuals with allergic asthma. 

Hypnotics. Common hypnotics are thiopental, propofol, midazolam, etomidate, ketamine and inhaled anesthetics. The incidence of hypersensitivity reactions with thiopental is rare. Recently, thiopental was involved in less than 1% of allergic reactions in France [9]. Ever since Cremophor EL, used as a solvent for some non-barbiturate hypnotics, has been avoided, many previously reported hypersensitivity reactions have disappeared. In the last French surveys, reactions to propofol accounted for less than 2.5% of allergic reactions, and reactions to midazolam, etomidate or ketamine appear to be really rare [9]. Finally, no immune-mediated immediate hypersensitivity reaction involving isoflurane, desflurane or sevoflurane has been reported despite their wide use. 

Irritant contact dermatitis results from first-time exposures to irritating substances such as soaps, plants, cleaning solutions, or solvents. Allergic contact dermatitis occurs after an initial sensitivity and further exposure to allergenic substances, including poison ivy, latex, and certain types of metals. 

Enviromnent and health-related problems Bio varnishes , i.e. varnishes based on natural, renewable raw materials, were developed as close-to-nature alternatives (substitutes) i.a. as a reaction to the so-called German wood preservative scandal and indoor pollution due to chemical solvents. Nevertheless, they have until now had a relatively high content of volatile bio-organic solvents, which may cause irritations, allergic and neurotoxic reactions, and contribute to the formation of tropospheric ozone. 

Beck MH, King CM Allergic contact dermatitis to epichlorohydrin in a solvent cement. Contaa Derm 9 315, 1983... 

In the context of skin sensitization bioavailability can be seen as the capacity of the compound to reach the viable epidermis, where it interacts with keratinocytes and Langerhans cells. This capacity is dependent on its molecular weight and solubility in polar and apolar solvents [115]. Importantly, potency prediction solely on the basis of cell culture models (steps 3 and 4) does not account for skin penetration rate and may thus wrongly predict potency in vivo. Possible in vitro approaches to detect allergic capacity of chemicals/pharmaceuticals are presented in Table 18.5. 

A study of substrate solubility and phase-partitioning behavior in a wide range of solvent concentrations by Truppo et al. led to a fourfold decrease in enzyme charge with an increase in product enantiomeric excess. The process was successfully run at 400-L scale yielding the desired product with 99.73%ee at 50% conversion with the optimized conditions [86]. The DP receptor antagonist 42 is being evaluated in clinical trials for the treatment of allergic rhinitis. 

Acrylate types of monomers and oligomers are known to be skin and eye irritants. Even if they do not cause irritation immediately, they may sensitize a person over a longer exposure and cause an allergic reaction.4 On the other hand, they represent much less hazard than common solvents (see Table 10.1). 

Toxic solvents, such as methyl alcohol, benzene, and chlorinated hydrocarbons, can penetrate the skin through cuts and abrasions. On contact, these solvents cause chronic dermatitis and allergic skin reactions in susceptible individuals. 

Normal (synthetic) paint can usually create serious problems for MCS patients. It s thus best to look for natural paint, namely those kinds based in minerals or plants. Some paints contain a natural solvent and others use water for dilution. Even natural solvents can sometimes cause allergic reactions in sensitive people, so be careful. Natural paints based in water are without a doubt the safest for MCS patients. In any case, always first put some paint on a small out-gassed board and place it in your home to see if you react to it (perhaps even put the board next to your bed). Never paint your entire home or safe room in one go First do the board test, then paint a wall, then paint a room and see if everything is still all right. Only then should you proceed with other rooms. See Part VIfor several natural and organic solutions or go to www.the-abc-of-mcs.com under Living. ... 

Due to its emollient properties it is found in products like soaps, hair conditioners, skin moisturizers and lipsticks. It is also employed as a hair pomade, particularly popular in tropical regions where it is reputed to prevent hair from going grey unfortunately there is no scientific evidence to support this. In aromatherapy the emollient properties of the oils are put to use for massage blends and skin creams. Coconut oil, particularly the solvent extracted, has been implicated in allergic reactions so a cautionary approach is advisable. 

The most common types of damage caused by chemicals in workers is probably to the lungs and to the skin. These are the main sites of the body that are exposed to chemicals. The most common industrial disease is dermatitis, which accounts for more working days lost than all the other industrial diseases together. If solvents or chemicals that workers handle come into contact with their hands, this can lead to irritation. More serious is contact dermatitis which results from repeated exposure over time. Sometimes serious allergic dermatitis occurs, where the chemical acts to sensitize the skin. Workers in the paper and printing industry are prone to skin diseases, and photographic chemicals, metals, resins, and coal tar derivatives can all sensitize the skin. As we have seen, certain chemicals, such as dioxins, can cause a particularly severe form of acne, chloracne. 

NPC is ideally suited for the analysis of compounds prone to hydrolysis because it employs nonaqueous solvents for the modulation of retention. An example of the use of NPC in the analysis of a hydrolysable analyte was demonstrated by Chevalier et al. [28] for quality control of the production of benorylate, an ester of aspirin. A major issue in benorylate production is the potential formation of impurities suspected of causing allergic side effects therefore monitoring of this step is critical to quality control. The presence of acetylsalicylic anhydride prohibited the use of RPLC since it can be easily hydrolyzed in the water-containing mobile phase. However, an analytical method based on the use of normal-phase chromatography with alkylnitrile-bonded silica as the stationary phase provided an ideal solution to the analysis. Optimal selectivity was achieved with a ternary solvent system hexane-dichloromethane-methanol, containing 0.2 v/v% of acetic acid to prevent the ionization of acidic function and to deactivate the residual silanols. The method was validated and determined to be reproducible based on precision, selectivity, and repeatability. 

Acute toxic contact dermatitis may be induced by a single application of a toxic material. One local inflammatory skin reaction is characterized by erythema and oedema. This type of reaction occurs following contact with materials such as acids, alkalis, solvents, and cleansers and is rarely associated with topical application of medicinal or cosmetic products. In contrast, irritant contact dermatitis (a superficial non-immuno-logically based reaction) may occur after repeated exposure to many substances, including topical pharmaceutical agents. The reaction is usually localized to the site of exposure and usually diminishes after the stimulus has been removed. Some materials can stimulate an immune response following an initial topical application. Any future exposure may result in an inflammatory immune reaction, an allergic contact dermatitis, or sensitization. 

The literature is replete with reports of various allergic-type reactions to preservatives (parabens, chlorocresol), antioxidants (propyl gallate, metabisulphite), surfactants and solvents. The list is too long to be discussed in this article but Ref. contains a... 

In 11 patients allergic to topical minoxidil lotion, patch tests showed that four were positive to minoxidil itself (11). Propylene and butylene glycol are used as solvents for minoxidil in topical formulations. Nine of the 11 patients appeared to have positive patch tests to propylene glycol and one of the 11 reacted to its alternative butylene glycol. 

Most systemic reactions after intravenous fluorescein are allergic, but in the past some were due to contamination with dimethylformamide, an industrial solvent (14). It is difficult to predict adverse effects by intracutaneous testing. A delayed allergic response, developing a few hours after intravenous fluorescein dye injection, can occur (15). It is recommended that a complete allergy evaluation be performed in aU patients who have adverse reactions to fluorescein, in order to differentiate true allergic reactions from other tjrpes of reactions (16). 

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