Environmental Engineering Reference
In-Depth Information
As an example, Polynesian culture has depended heavily
on fi sh for over 20 0 0 years. It is conceivable that during this
period, Polynesians would have been impacted by natural
emissions of volcanic mercury and developed practices that
steered people away from the fi sh most contaminated by
such emissions. Dellinger et al. (2005) reported a Tahitian
taboo that bans women from eating “outside fi sh”—fi sh
from outside the lagoon—during pregnancy and while
nursing. Similarly, a Hawaiian practice bans women from
eating two specifi c types of pelagic, piscivorous fi sh during
pregnancy. In limiting Polynesian women to the smaller
and often nonpiscivorous fi sh of lagoons, these practices
in effect reduce the health risks from mercury while main-
taining the nutritional benefi ts of eating fi sh.
As another example, among Native American Ojibwe
tribes, walleye is a traditional food that is often consumed
with wild rice. Although walleye is a piscivorous fi sh that
is potentially high in mercury, wild rice provides a supple-
mentary source of selenium (Dellinger, 2004) and may
mitigate some of mercury's adverse effects, as noted earlier.
Dellinger further noted that selenium content varies con-
siderably among different stands of rice (unpublished data)
and that according to anecdotal reports, the Ojibwe favor
certain rice stands, possibly those that are higher in sele-
nium. Thus, this traditional diet may be allowing Ojibwe
fi sh consumers to obtain dietary health benefi ts while
reducing mercury-related health risks, and may be another
instance of traditional ecologic knowledge at work.
The possibility that these practices may be functioning
as informal “guidelines” that both maintain benefi ts and
mitigate risks provides reason to be cautious about encour-
aging changes to long-established harvesting traditions
that are not yet fully understood.
Dellinger (2004) cites an instance of one tribal nutritionist
who, when asked what advice she gives to expectant moth-
ers, replied that she tells them, “Don't smoke, don't drink,
and don't eat fi sh.” In other cases, advisories have not been
developed for traditional populations at all, leaving only
general-population advisories to inappropriately advise
them.
However, this trend began changing in about the mid-
1990s, and now some traditional populations take a more
active role in developing their own advisories and their
own strategies for communicating the risks and benefi ts of
fi sh consumption to community members.
Communicating Risks and Benefi ts
The Importance of Communication
When done properly, risk assessment and risk management
can lead to useful and well-designed fi sh advisories. However,
before a fi sh advisory can have an impact on consumption
behaviors, it must be communicated to its target audience
successfully. Research indicates that the impacts of adviso-
ries for both noncommercial and commercial fi sh can vary
widely (Jardine, 2003), and illustrates some of the potential
challenges faced by communicators of advisory information.
A study by Oken et al. (2003), for example, suggested
that after the USFDA issued a mercury advisory in 2001
recommending that pregnant women avoid eating certain
long-lived predatory fi sh and limit their consumption of all
other fi sh, pregnant women acted in accordance, reducing
their total fi sh consumption by 1.4 servings per month. The
authors pointed out that this advisory was well publicized
through the mainstream media and health care providers.
(An aside: these authors questioned the public health impli-
cations of the advisory's apparent success in altering con-
sumption behavior, given the potential nutritional benefi ts
of fi sh for the developing fetus.)
Meanwhile, other studies suggest that the advisory mes-
sage does not always get across to consumers. A telephone
survey by Imm et al. (2005) showed that only about half of
the adults who ate fi sh caught from the Great Lakes were
aware of applicable fi sh advisories. This rate was the same
as that found in a similar, initial survey conducted almost a
decade earlier. Moreover, despite a campaign to raise aware-
ness of fi sh advisories among women, awareness in this
group dropped from 38 to 30% between the two surveys.
Similarly, in a study of two Canadian populations (Jardine,
2003), only about half to one third of people were aware
of applicable fi sh advisories, and only about half of those
who were aware knew which species of fi sh were included
in the advisory.
In other cases, studies show that, even if successfully
delivered, advisory messages can be misconstrued. Many
participants in Jardine's study (2003) indicated they had
ceased eating
all
fi sh from a local area covered under an
advisory, despite the advisory applying only to specifi c fi sh
EFFORTS TO BALANCE RISKS AND BENEFITS
Health agencies and experts around the world have recog-
nized the important role of locally caught fi sh in the diets
and cultures of traditional populations for several decades
(Department of Health and Welfare, Canada, 1979; WHO,
1999; USEPA, 2000; International Joint Commission [IJC],
2004). For example, a 1999 report from a World Health
Organization (WHO) committee on food additives stated:
The Committee noted that fi sh makes an important contri-
bution to nutrition, especially in certain regional and ethnic
diets, and recommended that its nutritional benefi ts be
weighed against the possibility of harm when limits on
methylmercury concentrations in fi sh or fi sh consumption
are being considered. (WHO, 1999)
But despite this long-standing recognition of the unique
benefi ts of fi sh for traditional populations, in practice,
historical efforts to alter the fi sh-consumption patterns
of such populations have often focused on these groups'
higher risks from mercury while failing to adequately con-
sider the risks introduced by limiting fi sh consumption.
