Effect of irrigation with lake water containing microcystins on microcystin content and growth of ryegrass, clover, rape, and lettuce

Abstract

The effect of irrigation with lake water containing a variety of microcystins on accumulation of toxins, or toxin metabolites, and plant growth in ryegrass, clover, rape, and lettuce, was investigated in a glasshouse experiment. The plants were grown in sand culture and received either three or six applications of lake water, which was applied either directly to the sand surface or to the plant shoots. As determined by LC-MS, each plant received 170 mug of a mixture of 10 different microcystins per application. Microcystins in plant samples were extracted with 70% methanol and analyzed by Adda-specific ELISA. For the shoot application treatment, microcystins were not present at measurable levels in shoots of ryegrass or rape, but were present in lettuce [0.79 mg/kg dry weight (DW)] and clover (0.20 mg/kg DW). Total microcystin concentration in roots did not vary greatly depending on whether treatment water was applied directly to the sand, or reached the roots via run-off from the shoots. Microcystins in roots were highest in clover (1.45 mg/kg DW), intermediate in lettuce (0.68 mg/kg DW) and low in ryegrass (0.20 mg/kg DW), and rape (0.12 mg/kg DW). There was no evidence for root-to-shoot translocation of microcystins. Three applications of microcystins reduced shoot DW of ryegrass, rape and lettuce, and increased root DW of ryegrass and lettuce. Clover DW was not changed by treatment with microcystins. The results show that irrigation with water containing microcystins has the potential to move microcystins into farm animal and human food chains at concentrations that can exceed recommended tolerable limits.

Review of 130 years of research on cyanobacteria in aquatic ecosystems in Serbia presented in a Serbian Cyanobacterial Database

“…Therefore, the health risks to people and animals due to the consumption of agricultural products irrigated with cyanotoxin-containing water must be taken seriously (Codd et al, 1999;Crush et al, 2008;Saqrane et al, 2009;Chen et al, 2010;Drobac, 2015).…”

The effect of risk perception on public preferences and willingness to pay for reductions in the health risks posed by toxic cyanobacterial blooms

“…Affected waters include those used for drinking water supplies, livestock watering, fishing, crop irrigation and recreation . Human exposure to cyanobacterial blooms and their toxins is potentially widespread and can occur through several routes including accidental and/or incidental dermal contact, ingestion and inhalation during recreational and occupational activities (Pilotto et al, 2004;Stewart et al, 2006;Caller et al, 2009) and through the consumption of ineffectively-treated drinking water (Falconer et al, 1983), shellfish and finfish (Falconer et al, 1992) and spray-irrigated crops (Codd et al, 1999;Crush et al, 2008).…”

Effects of microcystin-LR, linear alkylbenzene sulfonate and their mixture on lettuce (Lactuca sativa L.) seeds and seedlings

“…Therefore, it is possible for a large amount of MCs to be released into cropland and crops may be at potential risk of exposure. As a result, the risk of MCs to soil/cropland has received considerable attention from scientists worldwide (Chen et al 2004(Chen et al , 2006Pflugmacher et al 2006Pflugmacher et al , 2007Crush et al 2008).…”