Phenotypic and behavioral defects caused by barium exposure in nematode Caenorhabditis elegans

To examine the possible phenotypic defects from barium exposure, a model organism, Caenorhabditis elegans, was chosen to analyze the multiple toxicities in barium-exposed animals. Endpoints of life span, body size, brood size, generation time, head thrash, and body bend were selected for the assessment of barium toxicity. High concentrations (75 microM and 200 microM) of barium exposure caused severe life-span defects. Body sizes of exposed animals were markedly reduced compared to the controls, and high concentrations of barium exposure (75 microM and 200 microM) caused the appearance of vulva abnormality. In addition, barium exposure resulted in severe defects in reproductive capacity and reproductive speed. Body bends and head thrashes were also severely impaired after barium exposure. Furthermore, the stress responses to barium exposure suggest severe barium toxicity. The observed severe locomotion behavior and life-span defects in nematodes might be largely due to the deposition of barium toxicity in the muscle and intestine systems, respectively. Our data suggest that barium exposure could cause multiple biological defects by affecting the life span, development, reproduction, and locomotion behaviors. These multiple biological defects provide a new evaluation system to monitor the toxicity from barium exposure.