Monday, January 02, 2006

Aflatoxin - Back to the Future

Date: 31 Dec 2005
Source: FOX 30 Dec 2005 [edited]

Contaminated dog food which was sold in 22 states killed nearly 2
dozen dogs and sickened 18 more, the Food and Drug Administration said

The deaths and illnesses sparked an FDA investigation into the pet
food made by the Diamond Pet Food Company at its Gaston, South
Carolina, manufacturing plant. The FDA said so far 23 animal deaths
have been linked to the pet food.

The company, based in Beta, Missouri, issued a recall of 19 varieties
of dog and cat food on 21 Dec 2005 because some of the pet food made
at the Gaston facility was discovered to contain aflatoxin.

Aflatoxin, a naturally occurring chemical that comes from a fungus
sometimes found on corn and other crops, can cause severe liver
damage. Aflatoxin poisoning can cause sluggishness, a lack of appetite
and in severe cases severe vomiting, fever and jaundice.


BrooklynDodger comments: When the Dodger was starting toxicology school, the culture war over industrial chemicals or natural products as the main risk was starting out. This later sparked the Bruce Ames turn to the dark side.

Aflatoxin was originally discovered as the cause of "Turkey X Disease" which the Dodger recalls to be a massive die off of turkeys in Europe, maybe England, arising from moldy peanuts from Africa being made into chickenfeed [well, turkey feed]. Fox News neglected to mention aflatoxin as a carcinogen. Or, as they say, a "potent" carcinogen meaning small doses causing liver tumors in animals, and considerable epidemiology in people. There's a hypothesis that high liver cancer in southeast asia and low liver cancer in US and Europe are due to afflatoxins, although there's a competing hypothesis that hepatitis is the reason.

There are a series of aflatoxin structures, which have initials. The Dodger has decided not to hold the Dodger's breath for a mention of the workers exposed to aflatoxin-contaminated materials being made into pet food.

The mold is aspergillus flavius. There's a lot of aspergillus around, notably aspergillus niger which is found sometimes on onions you buy. AF will grow on garlic as well.

Chemical methods are used for measuring aflatoxin contamination. The Dodger imagines that testing for traces of aflatoxins is complex and expensive. Human peanut butter is surveyed, the Dodger believes. Although visible inspection of materials is also employed.

The Dodger would hope some of the modern DNA technology could be applied to this potential for mold danger. Like, find the gene or genomic signature in AF which controls afflatoxin manufacture. Screen lots of other molds, starting with the rest of the aspergillus family for this signature, see if it's there, then test whether these make AF. The Dodger imagines there are strains within AF that make more of less aflatoxin.

Would any of this new information change public health behavior? Rapid and cheap methods of measuring microbial contamination might inform some practices which are now procedure based [controll of legionella in cooling towers] or organoleptic [pick the moldy peanuts out of the pile, destroy the whole pile is a sample has too many moldy peanuts.]

This may be more likely to happen because dogs got sick, than if people got sick.

[Another chemical totally fallen from view is solanine, a neuroactive alkaloid found in the green part of potato eyes.]

No comments: