The growing use of lithium (Li) in industrial and energetic applications and the inability to completely recycle the alkali metal will most likely increase anthropogenic emissions and environmental concentrations in the future. Although non-essential to plants, Li+ is an important ultra-trace element in the animal and human diet and is also used in the treatment of e.g. mental disorders. Most of the lithium is consumed with the drinking water and vegetables, but concentrations in foodstuffs vary with the geochemistry of the element. In order to identify potential risks and to avoid an overmedication due to consumption of Li rich or Li contaminated foods it is advisable to identify background levels and to derive recommended Daily Allowances (RDAs) for the element. Although Germany does not possess large amounts of primary or secondary resources of lithium, geochemical investigations (mineral and ground waters and soils) in this country confirm a wide variation of environmental concentrations with generally higher levels in the southwest. Despite the large number of soil and water data, only very few data exist on lithium concentrations in plants and its phytotoxicity. Within the scope of present study common grassland plant species were sampled in regions of SW-Germany with reportedly high geogenic levels of Li. The data are discussed with regard to literature surveys and existing reference values. Since lithium has phytotoxic effects a greenhouse experiment was performed with different Li salts (LiCl and Li2CO3) and plant species (maize, bean and buckwheat) to derive dose-response relationships for the endpoint shoot growth. While corn growth was not reduced significantly by soil concentrations of 118 ppm, EC50 values in buckwheat were 47 and 16 ppm for lithium derived from LiCl and Li2CO3, respectively.

Lange's metalmark butterfly, Apodemia mormo langei Comstock, is in danger of extinction due to loss of habitat caused by invasive exotic plants which are eliminating its food, naked stem buckwheat. Herbicides are being used to remove invasive weeds from the dunes; however, little is known about the potential effects of herbicides on butterflies. To address this concern we evaluated potential toxic effects of three herbicides on Behr's metalmark, a close relative of Lange's metalmark. First instars were exposed to recommended field rates of triclopyr, sethoxydim, and imazapyr. Life history parameters were recorded after exposure. These herbicides reduced the number of adults that emerged from pupation (24–36%). Each herbicide has a different mode of action. Therefore, we speculate that effects are due to inert ingredients or indirect effects on food plant quality. If these herbicides act the same in A. mormo langei, they may contribute to the decline of this species.

Firefighting water additives are used to increase the rate at which fires can be extinguished. The majority of ecotoxicological research has focused on firefighting formulations containing perfluorinated compounds as additives, due to the persistence and bioaccumulative nature of the perfluorinated constituents. A number of relatively new additives have come on the market to replace the products containing perfluorinated compounds. The potential effect of these new additives on the environment has been largely unstudied. This study investigated the toxicity of six firefighting water additives: Eco-Gel™, ThermoGel 200L™, FireAde™, Fire-Brake™, Novacool Foam™, and F-500™ to terrestrial biota. Terrestrial organisms could be exposed to firefighting water additives through leaching into soil and/or runoff following a firefighting event or through direct aerial application during a forest fire. Toxicity to three plant species was assessed through seedling germination and emergence tests: Fagopyrum esculentum (buckwheat), Raphanus raphanistrum subsp. sativus (radish), and Rudbeckia hirta (black-eyed Susan). The effects of firefighting water additives on three soil invertebrates, the collembolan Folsomia candida, the earthworms Eisenia andrei, and Dendrodrilus rubidus, were also investigated using static acute tests to estimate EC₅₀/LC₅₀s. The concentration that resulted in a 50% reduction in survival (LC₅₀) for the acute toxicity tests conducted with F. candida ranged from 3 (Eco-Gel) to 0.175% (Novacool) by volume. Comparatively, the acute toxicity of two firefighting water additives to D. rubidus could not be determined, as a 50% reduction in survival was not observed. A number of firefighting water additives were found to pose a hazard to terrestrial organisms based on a worst-case exposure scenario of direct application at the greatest recommended application rate for a class A fire (e.g., wood, paper). The firefighting water additive F-500 was found to pose a hazard (HQ ≥ 1) for all species tested, except for the acute test conducted with D. rubidus. Comparatively, Eco-Gel posed a hazard for only the acute and chronic tests with F. candida. This study represents the first comparative deterministic risk assessment of firefighting water additives to terrestrial ecosystems.

Many airborne and soil-borne nanoparticles (NPs) can enter plants, which are the primary producers in the food chain; recently, studies on the genotoxic effects of NPs on plants are emerging. In the present study, the phytotoxic and genotoxic effects of ZnO and CuO NPs on buckwheat (Fagopyrum esculentum) seedlings were estimated. The inhibition of root growth and biomass at the tested concentrations of NP suspensions and dissolved free ion suspensions were compared. Changes in root morphological features and localization of NPs inside the root epidermis cells were observed. Growth of root treated with ZnO NPs (84.9 and 89.6 %) and CuO NPs (75.4 and 80.1 %) at 2,000 and 4,000 mg L -1, respectively, was decreased significantly than control. The root morphological features and NP incorporation into the root epidermal cells at a high dose of NP showed completely different patterns compared to those for the controls. Through random amplified polymorphic DNA assays for comparison of the effect of ZnO and CuO NPs on DNA stability, it was shown as different DNA polymorphisms at 2,000 and 4,000 mg L-1 of ZnO and CuO NPs, compared to those for controls. Our results provide the first clue to the genotoxic effects of ZnO and CuO NPs on early growth of edible plants such as buckwheat. © 2013 Springer Science+Business Media Dordrecht.

In this work, buckwheat husks (Fagopyrum esculentum) were modified by acid treatment and posteriorly employed to remove the ketoprofen in batch adsorption. The characterization results indicated that a more irregular surface with new empty spaces was generated after acid treatment. The adsorptive process was favored at acidic pH = 3. The dosage of 0.85 g L⁻¹ was fixed for the kinetic and isothermal tests, obtaining good removal and capacity indications. The kinetic studies were better represented by pseudo-second-order, obtaining an experimental capacity of 74.3 mg g⁻¹ for 200 mg L⁻¹ of ketoprofen. An increase in temperature negatively affected the adsorption isotherm curves, resulting in a maximum capacity of 194.1 mg g⁻¹. Thermodynamic results confirmed the exothermic nature of the process with physical forces acting. The adsorbent presented high efficiency in treating a synthetic effluent containing different drugs and salts, 71.2%. Therefore, adsorbent development from buckwheat husks treated with a strong acid is an excellent alternative, given the good removal results and the low cost for its preparation.

We aimed to examine the influence of benzene and of three dimethyl sulfoxide (DMSO) plant extracts—buckwheat (Fagopyrum Esculentum), rooibos (Aspalathus linearis), and vitex, (Vitex Agnus-Castus), and the combination of benzene with these three plant extracts on basic ovarian cell functions. Specifically, the study investigated the influence of benzene (0, 10, 100, or 1000 ng/mL) with and without these three plant additives on porcine ovarian granulosa cells cultured during 2 days with and without these additives. Cell viability, proliferation (accumulation of proliferating cell nuclear antigen, PCNA), apoptosis (accumulation of Bcl-2-associated X protein , bax), and the release of progesterone (P) and estradiol (E) were analyzed by the Trypan blue test, quantitative immunocytochemistry, and enzyme-linked immunosorbent assay, respectively. Benzene reduced cell viability, as well as P and E release. Plant extracts, given alone, were able directly promote or suppress ovarian cell functions. Furthermore, buckwheat and rooibos, but not vitex prevented the inhibitory action of benzene on cell viability. Buckwheat induced the stimulatory action of benzene on proliferation. Rooibos and vitex promoted benzene effect on cell apoptosis. All these plant additives were able to promote suppressive action of benzene on ovarian steroidogenesis.These observations show that benzene may directly suppress ovarian cell viability, P, and E release and that buckwheat, rooibos, and vitex can directly influence ovarian cell functions and modify the effects of benzene—prevent toxic influence of benzene on cell viability and induce stimulatory action of benzene on ovarian cell proliferation, apoptosis, and steroidogenesis. The observed direct effects of benzene and these plants on ovarian cells functions, as well as the functional interrelationships of benzene and these plants, should be taken into account in their future applications.

This study examines whether selected functional food and medicinal plants can mitigate the adverse effects of xylene on ovarian cells. The influences of xylene (0, 10, 100, or 1000 ng/mL), buckwheat (Fagopyrum esculentum), rooibos (Aspalathus linearis), vitex (Vitex agnus-castus), extracts (10 μg/mL each), and a combination of xylene with these plant additives on cultured porcine ovarian granulosa cells are compared. Cell viability, proliferation (PCNA accumulation), apoptosis (accumulation of bax), and release of progesterone (P4) and estradiol (E2) were analyzed by the trypan blue tests, quantitative immunocytochemistry, and enzyme-linked immunosorbent assays, respectively. Xylene suppressed all measures of ovarian cell function. Rooibos prevented all of xylene’s effects, whereas buckwheat and vitex prevented four of five of the analyzed effects (buckwheat prevented xylene influence on viability, PCNA, bax, and E2; vitex prevented xylene action on viability, PCNA, and P4 and E2). These observations show that xylene has the potential to suppress ovarian cell functions, and that buckwheat, rooibos, and vitex can mitigate those effects, making them natural protectors against the adverse effects of xylene on ovarian cells.

Fagopyrum esculentum commonly named as buckwheat plant is pseudocereal food crops and healthy herbs but is not known as a bioindicator of environmental condition. In the present study, the effects of ZnO nanoparticles (NPs) and microparticles (MPs) on plant growth, bioaccumulation, and antioxidative enzyme activity in buckwheat were estimated under hydroponic culture. The significant biomass reduction at concentrations of 10–2,000 mg/L was 7.7–26.4 % for the ZnO NP and 11.4–23.5 % for the ZnO MP treatment, (p < 0.05). ZnO NPs were observed in root cells and root cell surface by scanning electron microscopy and transmission electron microscopy analysis. Zn bioaccumulation in plant increased with increasing treatment concentrations. The upward translocation (translocation factor <0.2) of Zn in plant was higher with the ZnO NP treatment than that with the ZnO MP treatment. Additionally, reactive oxygen species generation by ZnO NPs was estimated as the reduced glutathione level and catalase activity, which would be a predictive biomarker of nanotoxicity. The results are the first study to evaluate the phytotoxicity of ZnO NPs to medicinal plant. F. esculentum can be as a good indicator of plant species in NP-polluted environment.