Cyanobacterial blooms pose a risk to wild and domestic animals as well as humans due to the toxins they may produce. Humans may be subjected to cyanobacterial toxins through many routes, e.g., by consuming contaminated drinking water, fish, and crop plants or through recreational activities. In earlier studies, cyanobacterial cells have been shown to accumulate on leafy plants after spray irrigation with cyanobacteria-containing water, and microcystin (MC) has been detected in the plant root system after irrigation with MC-containing water. This paper reports a series of experiments where lysis of cyanobacteria in abstracted lake water was induced by the use of hydrogen peroxide and the fate of released MCs was followed. The hydrogen peroxide-treated water was then used for spray irrigation of cultivated spinach and possible toxin accumulation in the plants was monitored. The water abstracted from Lake Köyliönjärvi, SW Finland, contained fairly low concentrations of intracellular MC prior to the hydrogen peroxide treatment (0.04 μg L −1 in July to 2.4 μg L −1 in September 2014). Hydrogen peroxide at sufficient doses was able to lyse cyanobacteria efficiently but released MCs were still present even after the application of the highest hydrogen peroxide dose of 20 mg L −1. No traces of MC were detected in the spinach leaves. The viability of moving phytoplankton and zooplankton was also monitored after the application of hydrogen peroxide. Hydrogen peroxide at 10 mg L −1 or higher had a detrimental effect on the moving phytoplankton and zooplankton.

Single crystals of synthetic nickel sulfate monohydrate, α-NiSO 4 ·H 2 O (space-group symmetry C2/c at ambient conditions), were subject to high-pressure behavior investigations in a diamond-anvil cell up to 10.8 GPa. By means of subtle spectral changes in Raman spectra recorded at 298 K on isothermal compression, two discontinuities were identified at 2.47(1) and 6.5(5) GPa. Both transitions turn out to be apparently second order in character, as deduced from the continuous evolution of unit-cell volumes determined from single-crystal X-ray diffraction. The first structural transition from αto β-NiSO 4 ·H 2 O is an obvious ferroelastic C2/c−P1̅ transition. It is purely displacive from a structural point of view, accompanied by symmetry changes in the hydrogen-bonding scheme. The second βto γ-NiSO 4 ·H 2 O transition, further splitting the O2 (hydrogen bridge acceptor) position and violating the P1̅ space-group symmetry, is also evident from the splitting of individual bands in the Raman spectra. It can be attributed to symmetry reduction through local violation of local centrosymmetry. Lattice elasticities were obtained by fitting second-order Birch−Murnaghan equations of state to the p-V data points yielding the following zero-pressure bulk moduli values: K 0 = 63.4 ± 1.0 GPa for α-NiSO 4 ·H 2 O, K 0 = 61.3 ± 1.9 GPa for β-NiSO 4 ·H 2 O, and K 0 = 68.8 ± 2.5 GPa for γ-NiSO 4 ·H 2 O.