Respiratory sensitization

Exposure effects Inhalation (general) Respiratory irritation Ingestion Skin/eye irritation Skin and respiratory sensitization Mutagenicity Teratogenicity Carcinogenicity ... 

RESPIRATORY SENSITIZER (asthmagen) A substance which can cause an individual s respiratory system to develop a condition which makes it over-react if the substance is inhaled again. Such an individual is sensitized over-reaction is then likely to occur at concentrations of the substance which have no effect on unsensitized persons and lead to characteristic symptoms, e.g. rhinitis (a runny nose), conjunctivitis or in severe cases asthma or alveolitis. 

Respiratory sensitizers Isocyanates proteolytic enzymes p-phenylene diamine complex salts of platinum cyanuric chloride. ... 

Respiratory sensitizers, e.g. isoeyanates or formaldehyde, result, in mild eases, in a sense of tightness of the ehest and oeeasionally a troublesome eough. Severe eases involve bronehial asdima. Refer to Table 5.6. With sueh sensitizers, eomplete eessation of eontaet is often followed by rapid reeovery but no further exposure is generally permitted. 

With some asthmagens, respiratory sensitization may oeeur at atmospherie eoneentrations below published limits. 

Colbalt Hydrogenations of solid fuels and fuel oils Manufacture of terephthalic acid High pressure production of aldehydes Lung irritation (hard metal disease) respiratory sensitization... 

The hazards with glutaraldehyde are those of irritation to the skin, eyes, throat, and lungs. It can cause dermal and respiratory sensitization, resulting in rhinitis and conjunctivitis or asthma. In the UK the Maximum Exposure Limit is just 0.05 ppm (8 hr TWA limit) and 0.05 ppm (15 min STEL) with a Sen notation (p. 93). 

The monomers, eatalysts or hardeners, or plastieizers ean inelude ehemieals with the potential to irritate the skin, mueous membranes or respiratory traet. Some ean promote skin or respiratory sensitization. The range of ehemieals in use is extremely wide, so that referenee should be made to the Materials Safety Data Sheet for eaeh speeifie formulation or variation of it identifiable by referenee to the supplier s proprietary name and eode number. Some eommon resin types are summarized in Table 5.55. 

An organic isocyanate (MDI or a pre-polymer) with a hydroxy compound. The isocyanates are potent respiratory sensitizers, the risk increasing with volatility... 

With the exception of epoxy resins, when a resin is fully polymerized it loses any irritant properties. However, associated materials, e.g. glass fibre used as a filler, or the dust from plywood or veneers, may promote initation. Partially-cured resins will retain some uritant properties. Traces of cutaneous or respiratory sensitizers liberated, e.g. by heating or machinery, may be problematic. 

SEN Capable of causing respiratory sensitization skin sensitizers have not been given a separate notation SK Can be absorbed through skin... 

Formaldehyde gas (Oxymethylene) HCHO 430 7.0-73.0 1.1 -21 Colourless Water soluble gas producing formalin solutions Suffocating odour Polymerizes readily Highly toxic Respiratory sensitizer... 

Save your breath respiratory sensitizers. (A guide for employers)... 

Breathe freely a workers information card on respiratory sensitizers The complete idiot s guide to CHIP 2... 

L 55 Preventing asthma at work how to control respiratory sensitizers... 

However, for some type of adverse effects, such as genotoxicity, carcinogenicity, and respiratory sensitization, it may not be possible from present knowledge to define this threshold of activity, so we may conclude that any level of exposure might carry some finite risk. In this case, OELs should be established at levels sufficiently low to avoid risks these are called pragmatic OELs. 

RESPIRATORY SENSITIZER A substance that may cause sensitization on inhalation, causing, e.g., asthma, rhinitis or extrinsic allergic alveolitis. 

It is important to remember that respiratory sensitization and asthma are related, but not identical, pathologies [31]. Asthma is a specific syndrome which appears to have genetic as well as environmental causes and there are numerous potential triggers which have been identified by immunotoxicologists [32], However, asthma is not the same disease as other respiratory hypersensitivity syndromes (sometimes referred to as chemical asthma, etc.) [33, 34], Various regulatory guidance documents have sought to deal with the latter disease entities to ensure that xenobiotics are assessed appropriately for their ability to induce immune-based pulmonary hypersensitivity reactions [35-37],... 

Another approach builds on the notion, widely accepted among immunotoxicologists (and probably true), that respiratory sensitizers (at least small molecular-weight chemicals) represent a subset of dermal sensitizers [42], Thus, assays for ACD, such as... 

Plitnick, L.M., Loveless, S.E., Ladies, G.S., Holsapple, M.P., Smialowicz, RJ., Woolhiser, M.R., Anderson, P.K., Smith, C., and Selgrade, M J., Cytokine mRNA profiles for isocyanates with known and unknown potential to induce respiratory sensitization, Toxicology, 207, 487, 2005. 

Immunoenhancement, which, as adverse effect, may lead to immune-mediated diseases such as hypersensitivity reactions and autoimmune diseases. Hypersensitivity reactions are the result of normally beneficial immune responses acting inappropriately, causing inflammatory reactions and tissue damage. The two most frequent manifestation of chemical-induced allergy are contact hypersensitivity and respiratory sensitization, both of which can have a serious impact on quality of life and represent a common occupational health problem. Hypersensitivity reactions are often considered to be increased at such a rate to become a major health problem in relation to environmental chemical exposure. 

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