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C. Picot et al.
value or a LOAEL determined from long-term toxicological studies, whereas
the latter is determined from acute toxicological studies. Moreover, in addition
to the traditional security factors employed for ARfD, the establishment of TDI
requires the use of a few others such as an uncertainty factor of 10 to extrapolate
subchronic to chronic exposure (Lewis 1995), leading to TDIs much lower than
ARfD. The finding, in this study, of a chronic exposure to OA via shellfish
consumption (only two- to five-fold below the ARfD) suggests that OA should
be considered as a possible cause for concern for human health.
Spirolides
Comparison with TTC: for SPX, the values of the mean, the median and 95th percentile intake from the probabilistic approach (5.4; 4.6 and 11.9 ng/kg bw/day,
respectively) are higher than the TTC (2.5 ng/kg bw/day). We made the
comparison with the most protective TTC because no (sub)chronic and genotoxic
data are available for SPX. Thus, the only exposure data do not allow us to reject
a chronic risk due to SPX.
Comparison with ARfD: as neither ARfD nor TDI have been allocated to SPX
by international committees, no comparison can be made. Though there is no
toxicological reference value, the calculations made in this study highlighted
the regular exposure of humans to low SPX doses. Thus, in the case where
toxicological data indicate chronic impact by SPX on health, it would be worth
taking into account exposure to SPX.
Impact of Cooking Process
The impact of cooking differs according to the phycotoxin. For lipophilic toxins, the
cooking increased the exposure by a factor about 1.5–2. For DAs, considering the
cooking process, the exposures decreased for cockles and razor clams but increased
for mussels, donax and hard shell clams (Tables 10.5 and 10.6). Thus, the actual
regulated level based on raw bivalves might over- or under-protect the consumers
when they cooked shellfish.
Conclusion
Further to the increasing number of reports about phycotoxin-induced intoxications
and deaths, these compounds have become a matter of concern for human health.
But, phycotoxin exposure assessments are almost non-existent because related data
about consumption and contamination are missing. This led us to study, in the same
C. Picot et al.
value or a LOAEL determined from long-term toxicological studies, whereas
the latter is determined from acute toxicological studies. Moreover, in addition
to the traditional security factors employed for ARfD, the establishment of TDI
requires the use of a few others such as an uncertainty factor of 10 to extrapolate
subchronic to chronic exposure (Lewis 1995), leading to TDIs much lower than
ARfD. The finding, in this study, of a chronic exposure to OA via shellfish
consumption (only two- to five-fold below the ARfD) suggests that OA should
be considered as a possible cause for concern for human health.
Spirolides
Comparison with TTC: for SPX, the values of the mean, the median and 95th percentile intake from the probabilistic approach (5.4; 4.6 and 11.9 ng/kg bw/day,
respectively) are higher than the TTC (2.5 ng/kg bw/day). We made the
comparison with the most protective TTC because no (sub)chronic and genotoxic
data are available for SPX. Thus, the only exposure data do not allow us to reject
a chronic risk due to SPX.
Comparison with ARfD: as neither ARfD nor TDI have been allocated to SPX
by international committees, no comparison can be made. Though there is no
toxicological reference value, the calculations made in this study highlighted
the regular exposure of humans to low SPX doses. Thus, in the case where
toxicological data indicate chronic impact by SPX on health, it would be worth
taking into account exposure to SPX.
Impact of Cooking Process
The impact of cooking differs according to the phycotoxin. For lipophilic toxins, the
cooking increased the exposure by a factor about 1.5–2. For DAs, considering the
cooking process, the exposures decreased for cockles and razor clams but increased
for mussels, donax and hard shell clams (Tables 10.5 and 10.6). Thus, the actual
regulated level based on raw bivalves might over- or under-protect the consumers
when they cooked shellfish.
Conclusion
Further to the increasing number of reports about phycotoxin-induced intoxications
and deaths, these compounds have become a matter of concern for human health.
But, phycotoxin exposure assessments are almost non-existent because related data
about consumption and contamination are missing. This led us to study, in the same