Developing a Biotechnological Tool for Monitoring Water Quality: In vitro Clone Culture of the Aquatic Moss Fontinalis Antipyretica

What potential do mosses have as biomonitors of POPs? A comparative study of hexachlorocyclohexane sorption

Persistent organic pollutants (POPs) pose a significant global threat to human health and the environment, and require continuous monitoring due to their ability to migrate long distances. Active biomonitoring using cloned mosses is an inexpensive but underexplored method to assess POPs, mainly due to the poor understanding of the loading mechanisms of these pollutants in mosses. In this work, Fontinalis antipyretica (aquatic moss) and Sphagnum palustre (terrestrial moss) were evaluated as potential biomonitors of hexachlorocyclohexanes (HCHs: α-, β-, γ-, δ-HCH), crucial POPs. Moss clones, grown in photobioreactors and subsequently oven-dried, were used. Their lipid composition and distribution were characterized through molecular and histochemical studies. Adsorption experiments were carried out in the aqueous phase using the repeated additions method and in the gas phase using an active air sampling technique based on solid-phase extraction, a pioneering approach in moss research. F. antipyretica exhibited greater lipid content in the walls of most cells and higher adsorption capacity for all HCH isomers in both gaseous and liquid environments. These findings highlight the need for further investigation of POP loading mechanisms in mosses and open the door to explore other species based on their lipid content.

The Biological Monitoring as a Source of Information on Environmental Pollution with Heavy Metals

The influence of environmental pollution on living organisms has been known for a long time, but it was not until the second half of the twentieth century that methodical studies on the influence of anthropopressure on changes in ecosystems began. Living organisms began to be used as biological indicators of environmental pollution. Cyclical and quantitative studies of pollutant concentrations in bioaccumulators have become the basis of modern biological monitoring (biomonitoring) of environmental pollution. Biomonitoring studies are carried out with the passive method (passive biomonitoring), in which living organisms occurring in their natural environment are analysed, and with active methods (active biomonitoring), in which, for example, plants living in the environment with low pollution are transferred and displayed in more polluted ecosystems e.g. heavy metals. The analysis of trace elements, including heavy metals accumulated in algae, mosses and lichens used in biological monitoring provides a lot of information on, among others concentration and origin of pollutants and the directions of their spread. Biomonitoring is used to assess the level of contamination of selected ecosystems, as well as the impact of individual emitters on the environment. An important element in determining the concentrations of trace elements in biological material used in biomonitoring is the proper planning of the experiment, taking into account, among others: methods of collecting or exposing samples, selection of analytical methods and methods of evaluation and interpretation of results. The aim of the presented long-term research, conducted by the Research Team of the Institute of Biology of the University of Opole, was to show that analytical techniques using biota samples can provide reliable data on the past, present and future state of the environment. However, it should be remembered that in order for the results of biomonitoring studies to be reliable and comparable, the applied research methodologies should be consistent and repeatable. In the presented research, Palmaria palmata and Spirogyra sp. algae, Pleurozium schreberi mosses, Hypogymnia physodes and bark of deciduous trees were used. In samples of biological material by the method of atomic absorption spectrometry, the concentrations of heavy metals, including Ni, Cu, Zn, Cd and Pb, were determined. On the basis of the conducted research, it was unequivocally stated that the biomonitoring methods are a good complement to the classic methods of environmental quality assessment. The analysis of the elements accumulated in the biological material provides us with information about the quality of the examined ecosystems, the introduced pollutants and their potential sources. This information allows for the introduction of effective measures to improve the quality of the environment.

Accumulation of polycyclic aromatic hydrocarbons in the devitalized aquatic moss Fontinalis antipyretica: From laboratory to field conditions

This work aims to test the feasibility of a Fontinalis antipyretica devitalized moss clone to uptake and accumulate polycyclic aromatic hydrocarbons (PAHs) from surface waters. To assess the capability of the devitalized clone to accumulate PAHs, in the laboratory, moss was placed in water and spiked with increasing concentrations of 16 PAHs, and under field conditions, the moss was transplanted to 22 sites of Galicia (Spain) rivers. In general, PAH concentrations in water samples were lower than the maximum allowable concentrations from Directive 2013/39/EU, so the sampling sites did not show water PAH contamination. The exponential accumulation kinetic in the laboratory trial highlights a good capability of the devitalized moss clone to accumulate total PAHs. In field experiments, the hydrogeological conditions and the low emission sources caused low concentrations of PAHs in the water system and, consequently, in the transplants, although an enrichment can be observed for several PAHs. Overall, the devitalized clone of F. antipyretica can uptake and accumulate PAHs in water and may be useful in bioremediation strategies.

Platyhypnidium aquaticum as Bioindicator of Metal and Metalloid Contamination of River Water in a Neotropical Mountain City

Water contamination is a major environmental problem in many cities of the world. Most water contamination results from industry and human activities that generate toxic substances (e.g., metals). Rheophilic and aquatic mosses are found in lotic ecosystems, and their morphological and physiological traits are responsive to ecological and pollution gradients. Here we hypothesized that the native rheophilic moss Platyhypnidium aquaticum (A. Jaeger) M. Fleisch exposed to polluted waters can bioaccumulate greater amounts of metals, and a metalloid, than P. aquaticum exposed to pollution-free water. To this aim, we tested the bioindicator capacity of the aquatic P. aquaticum for 15 metals (Cd, Pb, Zn, Fe, K, Ca, Na, Mn, V, Co, Ba, Cr, Al, Sr, and Mg) and one metalloid (As), in twelve river samples coming from three urban and one control zone along the Zamora river in the city of Loja. When compared to the control, our results showed that P. aquaticum in the Southern, Central, and Northern zones of the city bioaccumulated higher concentrations of Ba, Cd, Co, Fe, Mg, Mn, Na, Sr, Zn, and the metalloid As. On the other hand, concentrations of Al, Ca, Cr, Pb, and V in P. aquaticum tended to be lower in the control zone, but these differences were not significant. We suggest that the presence of these contaminants may be related to water pollution (e.g., residual discharges and a lack of treatment systems) along urban zones of the river. We report for the first time the utility of P. aquaticum as a model species for development of long-term biomonitoring programs of water contamination in South America. Passive biomonitoring with P. aquaticum can be a simple and low-cost method to obtain reliable data of the current state of water contamination with metals and metalloids in tropical regions.

Methodological advances to biomonitor water quality with transplanted aquatic mosses

The active biomonitoring technique has been demonstrated to be an excellent tool for monitoring water quality; however, further improvement of the protocol is urgently needed. The present study was carried out to determine the best options for various methodological aspects of monitoring some metals and metalloids (i.e. Al, As, Cd, Co, Cu, Fe, Hg, Ni, Zn and Pb): i) the type of transplant, ii) pre-exposure washing (with or without cellular extractants), iii) the ratio between moss weight and bag surface area, and iv) the depth at which the bags are exposed. The importance of the different methodological aspects in the outcome of biomonitoring studies was also assessed by considering the results of the present and other previously published studies. Regarding the type of transplant, the traditionally used net bags were the best option for enclosing the moss; in addition, washing the moss with extracellular extractants (i.e. EDTA) prior to exposure increased the sensitivity of the technique and reduced the required exposure time (i.e. one week). For the amount of moss packed in each bag, a ratio of 12.5 mg cm^-2 was the best choice. Finally, the depth at which the transplants were exposed did not affect pollutant accumulation (in shallow rivers, reservoirs or dams). Pollutant concentrations were also not affected by the existence of thermocline in deep waters during warmer months. Different methodological aspects involved in applying this technique determine the final concentrations of metals in moss. Although the influence of those was variable, for most elements (i.e. As, Cd, Co, Cu, Hg, Pb, Zn) 80% of the total variance was explained by 3-4 aspects, being species selection, devitalization treatment, duration of exposure, and number of transplants exposed the most important.