NIOSHTIC-2 Publications Search

Is ortho-phthalaldehyde a safe alternative to glutaraldehyde?

Anderson SE; Umbright C; Sellamuthu R; Fluharty K; Franko J; Jackson L; Kashon M; Johnson V; Joseph P
Toxicologist 2010 Mar; 114(1):66
Although ortho-phthalaldehyde (OPA) has been recommended as an alternative to glutaraldehyde for the sterilization and disinfection of heat-sensitive medical equipment, its toxicity has not been thoroughly investigated. The present study was designed to evaluate the dermal irritation and sensitization potential of OPA. Results of the Epiderm Skin Irritation Test identified OPA as a dermal irritant and furthermore, demonstrated that OPA is a more potent skin irritant than glutaraldehyde. Consistent with the in vitro results, exposure to 0.75% OPA induced irritancy when evaluated in a combined irritancy local lymph node assay (LLNA) exposed to 0.75% OPA. A concentration-dependant increase in lymphocyte proliferation was observed after OPA exposure with a calculated EC3 value of 0.051%, classifying this chemical as an extreme sensitizer. IgE-inducing potential was evaluated by phenotypic analysis of draining lymph node cells and measurement of total and OPAspecific serum IgE levels in the mice. The 0.1% and 0.75% exposed groups yielded significant increases in the IgE+B220+ cell population in the lymph nodes while only the 0.75% exposed group demonstrated significant increases in IL-4 mRNA in the draining lymph nodes and total and OPA specific serum IgE levels. A significant elevation in OPA-specific IgG1 was also observed after exposure to 0.75% OPA. These results demonstrated the dermal irritation and sensitization potential of OPA in an animal model raising concern about the skin irritation and sensitization potential of OPA among healthcare workers who are potentially exposed to the chemical.
Allergic-reactions; Biological-effects; Cell-biology; Cellular-reactions; Chemical-cleaning; Chemical-hypersensitivity; Exposure-assessment; Exposure-levels; Exposure-methods; Hypersensitivity; Laboratory-animals; Laboratory-testing; Lymphatic-system; Skin-exposure; Skin-irritants; Skin-irritants; Skin-sensitivity; Statistical-analysis
Publication Date
Document Type
Fiscal Year
Issue of Publication
NIOSH Division
Source Name
The Toxicologist. Society of Toxicology 49th Annual Meeting and ToxExpo, March 7-11, 2010, Salt Lake City, Utah
Page last reviewed: May 11, 2023
Content source: National Institute for Occupational Safety and Health Education and Information Division