The alkaloid cylindrospermopsin has been recognized of increased concern due to the global expansion
of its main producer, Cylindrospermopsis raciborskii. Previous studies have shown that bivalves can
accumulate high levels of cylindrospermopsin. Based on the potential for human health risks, a provisional
tolerable daily intake of 0.03 mg/kg-body weight has been recommended. However, the human
exposure assessment has been based on the cylindrospermopsin concentration in raw food items. Thus,
this study aimed to assess the changes on cylindrospermopsin concentration in edible mussels with
storage and processing time as well as cylindrospermopsin bioaccessibility. Mussels, (Mytilus galloprovincialis)
fed cylindrospermopsin-producing C. raciborskii, were subjected to the treatments and then
analyzed by LC-MS/MS. Mussels stored frozen allowed a significantly higher recovery of cylindrospermopsin
(52.5% in 48 h and 57.7% in one week). The cooking treatments did not produce significant
differences in cylindrospermopsin concentration in the mussel matrices (flesh), however,
cylindrospermopsin was found in the cooking water, suggesting that heat processing can be used to
reduce the availability of cylindrospermopsin. The in vitro digestion considerably decreased the cylindrospermopsin
availability in uncooked and steamed mussels, highlighting the importance in integrating
the bioaccessibility of cylindrospermopsinin in the human health risk assessment.