We know the risks for the public regarding the consumption or exposure to water contaminated with cyanotoxins. However, the knowledge of accumulation of cyanotoxins in fruits and vegetables after irrigation with contaminated water is limited. Within this project, we increase the knowledge regarding the accumulation of cyanotoxins in fruits and vegetables (salad, strawberry and carrot) and their potential risks.
Health risks of residual microcystine concentrations
Within the CYANTIR project, we investigate the possible health risks of irrigation practices with microcystine contaminated water. More specifically microcystin-LR (MC-LR), which is the most prevalent toxin produced by cyanobacteria. After irrigation, residual concentrations of microcystin can therefore be present in- or on- the crops and can be absorbed by the human body after consumption.
We selected three crops, that are mostly consumed raw, for this study e.g. lettuce, carrot and strawberry. They are irrigated under controlled circumstances with microcystin spiked water. Multiple concentrations of MC-LR will be tested. These concentrations are based on relevant literature in this field.
Specifically for strawberry and carrots, 2 irrigation methods are compared. The cultivation conditions and the irrigation with contaminated water mimic the common practice as closely as possible.
Calculation of exposure
We are making various quantitative (fresh weight, number of fruits per plant) and qualitative (phytotoxicity, damage, discoloration) observations during the trial. The microcystin content present in- the plant is determined at 3 different times:
- 1 week before harvest
- at harvest
- and 1 week after storage
We are using a LC-MS/MS method for this purpose. We perform a risk assessment based on consumer exposure pathways and exposure media. To calculate the exposure, we use a deterministic approach based on the latest Belgian consumption survey according to EFSA protocols.