[KimS]

General Knowledge:

http://www.newint.org/issue314/update.htm

The Brazil nut tree cannot be cultivated, as it depends on associated forest species for pollination and the seeding of its fruit. The tree grows to 50 metres in height and takes some 45 years to produce a first crop. In areas where forest conditions are altered, nut production quickly falls.

http://72.14.203.104/search?q=cache:...ient=firefox-a

Introduction
Brazil nuts have been widely promoted since the late 1980s as a product that meets
the twin goals of forest conservation and poverty reduction, and are marketed under
both Fair Trade and eco-friendly labels
1
. The Brazil nut industry fits well with the
objectives of European development co-operation, which since the 1992 Maastricht
Treaty
2
have been based increasingly on poverty reduction
3
. Furthermore, poverty is
recognised to be closely linked with environment protection.
4
Brazil nuts are probably
the most economically important plant product that is harvested sustainably from the
natural Amazonian forest, and Brazil nut harvesters include the poorest sectors of
society in a region with some of the highest levels of biodiversity in the world. As a
result, the European Union and its member nations have given considerable support to
the Brazil nut industry and related extractive systems.
5



First the good:
http://www.lef.org/protocols/cancer/colorectal_03.htm
Selenium is an essential trace element found in vegetables, cereals, grains, and nuts. Selenium reduces the incidence of colorectal cancer (Finley JW 2006), at least in part by increasing antioxidant levels that protect against cancer initiation (Peters U et al. 2006b); Wallace K et al 2003; Fleet JC 1997).
High selenium levels are associated with restoration of glutathione peroxidase levels (Ip C et al 1991), proper functioning of immune system cells, and a reduced occurrence of colorectal adenomas (Connelly-Frost A et al. 2006; Peters U et al. 2006a); Ferencik M et al 2003). By contrast, selenium deficiency increases susceptibility to colorectal cancer (Davis CD et al 2003; Kowal M et al 2003) and is associated with high levels of the tumor marker CA 19-9 (Lasch K et al 1999). Patients prone to colon adenomas and those with colon cancer have significantly lower selenium levels (less than 70 micrograms per liter (µg/L) (Fernandez-Banares F et al 2002; Milde D et al 2001; Psathakis D et al 1998).
In a double-blind, placebo-controlled trial, patients with colon adenomas presented with low serum levels of selenium before treatment, but supplemental selenium normalized their selenium levels (Al-Taie OH et al 2003). Reduced activity of this selenium-dependent enzyme is associated with increased risk and poor prognosis in colorectal cancer patients (Milde D et al 2001). In a double-blind, three-year intervention study of polyp-bearing patients, selenium (101 mcg) protected against the formation of new adenomas (Hofstad B et al 1998). A phase III clinical trial is investigating selenium to see how well it works in preventing the recurrence of polyps in patients with adenomatous colorectal polyps (for more information, visitwww.clinicaltrials.gov).
Brazil nuts, plant foods, tuna, cod, and eggs contain high levels of selenium.


Now the bad:


http://www.newint.org/issue314/update.htm

Aflatoxin thrives in the humid tropical forest environment. Nuts can only be collected once they have fallen to the forest floor and can often lie for months before gathering, exacerbating the potential for infection. The wet rainforest makes it difficult to keep gathered nuts dry and thereby prevent the fungus from spreading.

[myst]

I did a little bit of research on aflatoxin a while back. This is from Wikipedia:

http://en.wikipedia.org/wiki/Aflatoxin

No animal species is immune to the acute toxic effects of aflatoxins including humans; however, humans have an extraordinarily high tolerance for aflatoxin exposure and rarely succumb to acute aflatoxicosis.

Chronic, subclinical exposure does not lead to as dramatic of symptoms as acute aflatoxicosis. Children, however, are particularly affected by aflatoxin exposure which leads to stunted growth and delayed development.

One thing I found rather interesting (also from Wikipedia):

Studies have shown that concurrent infection with the Hepatitis B virus (HBV) during aflatoxin exposure increases the risk of hepatocellular carcinoma (HCC). As HBV interferes with the ability of hepatocytes to metabolize aflatoxins, an aflatoxin M1-DNA conjugate exists for a longer period of time in the liver, increasing the probability of damage to oncogenes such as p53.

The interesting part is how it relates to my raspberry research. This from http://www.jonbarron.org/documents/brellagic.htm :

Red raspberry ellagitannins prevent destruction of the P53 gene by cancer cells. P53 prevents mutagenic activity in cervical cells.