, J. Kapeles2
, E. Delacruz1
, G. DeGeorge1
- MB Research Laboratories, Spinnerstown, PA, United States
- Safariland Group, Casper, WY, United States
Oleoresin Capsicum (OC) is an oily resin found in cayenne and other varieties of peppers and is used in law enforcement as a debilitating
irritant and inflammatory agent. Although traditionally delivered as a liquid aerosol (“Pepper Spray”), combusted OC carried in smoke from
pyrotechnic devices has also proven effective. The short-term inhalation toxicity of OC-containing smoke was assessed using whole-body
inhalation exposure methodology. Five male and five female Crl:SD(CD) rats were exposed at a total smoke concentration of 19.4 mg/l for
five minutes. Particle size of the smoke was determined using cascade impaction; the mass median aerodynamic diameter (MMAD) was 1.9 µm.
The concentration of the total smoke was determined by gravimetric technique, and the corresponding OC concentration in air was calculated
based on the fraction of the combusted product containing OC. Animals were observed throughout exposure and daily for 14 days afterward.
Body weights were collected on Study Days 0, 7 and 14. Early in the exposure period, all rats displayed avoidant behaviors such as efforts
to escape the enclosures within the exposure chamber. By the end of the exposure period, all animals were lethargic, but regained normal
activity levels after removal from the chamber and being washed free of smoke residue. All rats displayed no adverse signs at three hours
post-exposure. All animals gained weight during the study, and survived to the scheduled necropsy.
- Respiratory Toxicology
- Chemical and Biological Weapons
- Safety Assessment: Nonpharmaceutical
- Chemical Weapons
Matthew J. Troese, Lisa Pratt, George L. DeGeorge
MB Research Laboratories, Spinnerstown, PA
This research project combined a 3D reconstructed human epidermal (RHE) tissue that is co-cultured with human plasmacytoid Dendritic Cells
(pDCs) for use as an in vitro CoCulture dermal sensitization assay. In this assay, RHE tissues were placed at the air-liquid interface above
a media suspension of pDC. The tissues are then exposed to test materials, and after 4 hours of incubation together, the RHE tissues and pDC
were separately cultured for an additional 20 hours. The RHE media was analyzed for IL-18 release by ELISA, and the pDC were analyzed for changes
in CD86 surface expression by flow cytometry. Two non-sensitizing irritants (Lactic Acid and Phenol), along with two weak/moderate sensitizers:
Eugenol and Hexylcinnamaldehyde, and two strong sensitizers: 1-Chloro-2,4-Dinitrobenzene and 4-Nitrobenzyl Bromide were assayed. A positive
response from the RHE tissues was determined to be a 2-fold increase in IL-18 secretion, and a 1.5 fold increase in CD86 expression on pDC.
Tissue viability was measured using the MTT assay. The responses we obtained in both the RHE tissue versus pDC were very consistent.
Increases in both secretion of IL-18 and expression of CD86 were detected after exposure to dermal sensitizers. A prediction model was
developed in which a sensitizer result for a chemical is defined as either a positive result in the RHE tissue (IL-18) or a positive result
in pDCs (CD86). From three individual experiments, and using a 2x2 contingency table to determine Cooper statistics, we obtained an Accuracy
of 100%, 83%, and 83% (89% mean Accuracy). All four of four sensitizers were positively predicted in each experiment (100% Sensitivity).
This research was funded by the Society of Toxicology Grant for Alternatives Research (sponsored by Colgate-Palmolive).
- Alternatives to Mammalian Models
- In Vitro Toxicology
- Dermal Sensitization