Assessing effects of legacy nuclear waste on plants: Sensitive fern (Onoclea sensibilis) gametophyte viability at the Chalk River site.

We evaluated the effects of chronic exposure to environmental radiological contamination on the reproductive fitness of sensitive fern (Onoclea sensibilis) by quantifying viability in haploid gametophytes of spores collected from ferns from background and contaminated areas of the Chalk River site. Dose rates measured in situ at field sites ranged from 60 to 849 μGy h, with effects possible at the more contaminated sites (greater than 400 μGy h). Fern spores were also irradiated from 1 to 1000 Gy to develop dose-response curves.