3.6. Implications for public health
To exceed the Provisional Tolerable Weekly Intake
(PWTI) for Cd (i.e. 7 mgkg1 wk1), it would be necessary
to ingest from 27 to 333 g of squid muscle per kg of body
weight for an average human body weight of 60 kg. This
represents consumption of 1.6–20 kg of squid muscle in a
week (Table 2). However, the PTWI would be reached with
only 15 gwk1 for the digestive gland of the four squid
species and for the gills of T. sagittatus (Table 2). This may
be an issue in countries (e.g. Japan), where squid digestive
glands are consumed. In southern Europe, small squids are
often eaten whole but the viscera of larger squid would not
normally be eaten.
In relation to Hg intake, the amount of squid tissue to
reach the PTWI for total Hg (5 mgkg1 wk1) would be
around 9 kg of Loligo or Todaropsis flesh per week or
around 4 kg of Todarodes flesh. Even for the tissue with the
highest Hg concentration, i.e. the digestive gland of
Todarodes, it would be necessary to eat more than
2.7 kg wk1 to exceed safe limits (Table 2). Knowing that
from 70% to 90% of Hg in squid tissues would be in
organic form (Bustamante et al., 2006a), the amount of
squid flesh to reach the methyl Hg PTWI would be 3.5–4.5
times lower compared to the values for total Hg, i.e.
between 2 and 2.6 kg of Loligo or Todaropsis flesh per week
and between 0.9 and 1.1 kg of Todarodes flesh.