Bryophytes, a group of terrestrial plants widely used in biomonitoring, are reviewed for their relation to heavy metals. In the present article, we summarized the knowledge on heavy metals pollution and accumulation effects on bryophytes. Mechanisms of tolerance and resistance are given as well.

Bryophytes (including mosses, liverworts and hornworts) are a heterogeneous group of terrestrial plants, which comprise over 24,000 species worldwide. Given the various biological activities reported from bryophytes, they have a huge commercial potential. Due to their minute size and rather small biomass in various ecosystems, bryophytes are a seldom part of ethnomedicine and rarely subject to medicinal and chemical analyses. Still, hundreds of novel natural products have been isolated from bryophytes. Bryophytes have been shown to contain numerous potentially useful natural products, including polysaccharides, lipids, rare amino acids, terpenoids, phenylpropanoids, quinones and many other specialized metabolites. Additionally, different bryophyte extracts and isolated compounds have shown antimicrobial, antiviral, cytotoxic, nematocidal, insecticidal, effects on smooth and non-striated muscles, weight loss, plant growth regulators and allelopathic activities. Bryophytes also cause allergies and contact dermatitis. All these effects highlight bryophytes as potential source for herbal remedies and production of chemicals to be used in various products.