Chloroform distribution and accumulation by combined inhalation plus oral exposure routes in rats

Abstract

The present investigation was undertaken to determine the distribution and accumulation of chloroform in the blood, liver, kidney and abdominal fat of rats after simultaneous exposure by two routes, inhalation and oral. To distinguish the contribution of each route, unmodified chloroform (CHCl₃) was administered by inhalation and deuterated chloroform (CDCl₃) was administered orally. Exposure by inhalation and oral administration resulted in CHCl₃ and CDCl₃ concentrations in the tissues which were significantly higher than when exposure was by either inhalation or oral administration alone. This is the first study to follow the contribution of each of two routes of chloroform exposure on chloroform distribution and accumulation in target tissues. Our results indicate that when assessing the toxicity and carcinogenicity of chloroform, exposure routes, especially the effects of exposure by multiple routes, must be taken into consideration.

Keywords:

• Chloroform
• deuterated chloroform
• combined exposure routes
• blood concentration
• tissue concentration
• mass spectrometer

Acknowledgment

We wish to express our thanks to Dr. David B. Alexander, Graduate School of Medical Sciences, Nagoya City University, for proofreading this manuscript.