Extractable Protein Levels in Latex Products and their Associated Risks, Emphasizing American Dentistry

Abstract

Background: Over 8% of the US population have detectable Type I Hevea latex IgE antibodies and, upon exposure to natural latex and rubber products, are at risk for potentially dangerous reactions, especially in dental settings where these products are exposed to mucosal membranes. Methods: Extractable antigenic protein levels were quantified in dental dams, examination gloves, and various other dental and rubber products. ASTM standards D6499 (antigenic protein) and D5712 (total protein) were used to quantify the protein content. Results: In dental dams, extractable protein content ranged from <3 to 130-200 μg/dm 2 , which are generally accepted by regulatory bodies to be low/nonsensitizing levels and high/potentially sensitizing levels, respectively. In addition, although examination gloves from Malaysian glove manufacturers consistently exhibited a lower extractable protein content (<9 μg/dm 2) than gloves from Thai manufacturers (16-23 μg/dm 2), these levels are both below the 50 μg protein/g latex film threshold accepted by FDA and used by manufactures. There was no correlation between extractable protein content and the price or thickness of dental dams or examination gloves. Most of the other assorted dental products tested displayed low extractable protein content (<2.5 μg/dm 2). Nearly all dental products made from natural rubber contained detectable antigenic Hevea proteins, subjecting previously sensitized patients and providers to risk of severe allergic reaction. A case study describes a female patient, with no previous history of Type I latex allergy, reacted severely to a dental dam mouth exposure, necessitating her admission to the intensive care unit (ICU) of a local hospital for management of respiratory failure, with discharge after 4 days. Conclusions: It is clear that some dental products may pose a significant risk of Type I latex protein allergy sensitization, due to repeated contact, and that a single exposure can induce a severe reaction in a previously sensitized person, even when no prior latex allergy history is known.

Durability Variation Among Medical Gloves Made from Existing and New Elastomers Poses a Risk to Public Health

“…One dental dam manufacturer does not leach their natural latex dams, so this concern is not without precedence. [ 24 ] Normal detergents in hot or cold water do not effectively extract entrained proteins remaining in unleached, fully cured natural latex films, but human fluids can do this during medical or dental procedures. Leaching is only effective during manufacture when applied to partially cured products.…”

Development of latex foam pillows from deproteinized natural rubber latex

“…Exposure to extractable residual chemicals (ERC) can caused Type IV delayed hypersensitivity reactions (48-96 hours after contact) such as vesiculation, erythema, swelling, cracking and itching of the skin at the site of contact 26,36 . Therefore, the ERC content of DPNR, LATZ and CNRL latex foam samples was determined.…”

“…Latex allergy symptoms can be mild, such as redness of skin and itching, or severe, such as wheezing, mucosal swelling and anaphylactic shock 21,23 . Although there is no evidence reported of NR latex foam pillows causing latex allergies, as is the case with NR latex gloves, the latex allergy issue has raised awareness among users of the potential risks of using other products, including pillows, made from NR latex foam 20,[24][25][26] .…”