Methyl methacrylate and respiratory sensitization: A Critical review

Abstract

Methyl methacrylate (MMA) is a respiratory irritant and dermal sensitizer that has been associated with occupational asthma in a small number of case reports. Those reports have raised concern that it might be a respiratory sensitizer. To better understand that possibility, we reviewed the in silico, in chemico, in vitro, and in vivo toxicology literature, and also epidemiologic and occupational medicine reports related to the respiratory effects of MMA. Numerous in silico and in chemico studies indicate that MMA is unlikely to be a respiratory sensitizer. The few in vitro studies suggest that MMA has generally weak effects. In vivo studies have documented contact skin sensitization, nonspecific cytotoxicity, and weakly positive responses on local lymph node assay; guinea pig and mouse inhalation sensitization tests have not been performed. Cohort and cross-sectional worker studies reported irritation of eyes, nose, and upper respiratory tract associated with short-term peaks exposures, but little evidence for respiratory sensitization or asthma. Nineteen case reports described asthma, laryngitis, or hypersensitivity pneumonitis in MMA-exposed workers; however, exposures were either not well described or involved mixtures containing more reactive respiratory sensitizers and irritants.The weight of evidence, both experimental and observational, argues that MMA is not a respiratory sensitizer.

Acrylic Resin Cytotoxicity for Denture Base: Literature Review

“…Local chemical irritation [8,9,19], hypersensitivity, mucosal inflammation and ulceration [8,9,11], burning sensation in the palatal mucosa, tongue, oral mucosa and oropharynx, pain, edema, swelling and local erythema and labial edema [5,9] and respiratory irritation [19] are reported clinical conditions. Additionally, fibrosis, necrosis, histiocytosis [3,6], inflammatory infiltrate and a thicker keratin layer [5] were observed in the tissues in contact with the acrylic resin.…”

Concomitant contact allergy to formaldehyde and methacrylic monomers in students of dental medicine and dental patients

“…Methacrylate-containing materials are almost always mixtures of methacrylates and acrylates, which contain inhibitors, activators and other reactive compounds. The examples include: reaction initiators (e.g., benzoyl peroxide), reaction activators (e.g., tertiary amines), cross-linking agents (e.g., formaldehyde), reaction inhibitors (e.g., hydroquinone) and resin carriers [3]. All of these additives are known contact sensitizers and several are known or suspected respiratory sensitizers and/or respiratory irritants [4,5].…”

Evaluation of exposures and health at a specialty chemicals plant, West Virginia.

“…For example, isocyanates, epoxy resins, and methyl methacrylate have been reported to cause or aggravate asthma [NIOSH 2004, Hannu et al 2009, Borak et al 2011. Isocyanates have been studied extensively in the literature, and in addition to asthma, have been associated with hypersensitivity pneumonitis, obstructive lung disease, non-asthmatic neutrophilic bronchitis, and contact dermatitis [NIOSH 2004, Pronk et al 2009, Pala et al 2011.…”