Toxicological analysis of limonene reaction products using an in vitro exposure system

Abstract

Epidemiological investigations suggest a link between exposure to indoor air chemicals and adverse health effects. Consumer products contain reactive chemicals which can form secondary pollutants which may contribute to these effects. The reaction of limonene and ozone is a well characterized example of this type of indoor air chemistry. The studies described here characterize an in vitro model using an epithelial cell line (A549) or differentiated epithelial tissue (MucilAir™). The model is used to investigate adverse effects following exposure to combinations of limonene and ozone. In A549 cells, exposure to both the parent compounds and reaction products resulted in alterations in inflammatory cytokine production. A one hour exposure to limonene + ozone resulted in decreased proliferation when compared to cells exposed to limonene alone. Repeated dose exposures of limonene or limonene + ozone were conducted on MucilAir™ tissue. No change in proliferation was observed but increases in cytokine production were observed for both the parent compounds and reaction products. Factors such as exposure duration, chemical concentration, and sampling time point were identified to influence result outcome. These findings suggest that exposure to reaction products may produce more severe effects compared to the parent compound.

Application of a modified gaseous exposure system to the in vitro toxicological assessment of tobacco smoke toxicants

“…The exposure of bacterial and mammalian cells at the air–agar or air–liquid interface to various test atmospheres such as WS and its gas vapour phase, biological and individual chemical pollutants has previously been described elsewhere [Aufderheide and Gressman, 2007; Pariselli et al, ; Schmalz et al, ; Wijte et al, ; Persoz et al, ; Anderson et al, ]. These studies have largely been based around the use of either the CULTEX ® or Vitrocell ® exposure modules.…”

Assessment of biological responses of EpiAirway 3-D cell constructs versus A549 cells for determining toxicity of ambient air pollution

“…Only one study that used diesel exhaust (DE) was relevant to ambient air pollution (Seagrave et al, 2007). Similarly, only one study using the MucilAir 3-D cell model at ALI conditions that is relevant to air pollution has been published (Anderson et al, 2013). While the EpiAirway ™ and MucilAir 3-D models have shown to better mimic biological responses in humans, it is difficult to assess the benefits of these models for air pollution studies due to the lack of peer reviewed studies comparing responses induced at ALI conditions in different cell culture models.…”

SPME as a promising tool in translational medicine and drug discovery: From bench to bedside

“…Generated in the chamber, secondary pollutants influenced the human alveolar epithelial cells (A549) and 3D models of highly differentiated epithelial tissue (MucilAirTM). Sampling gave information regarding chamber content [54].…”