Thread by @DrLizaMD

"An ounce of prevention is worth a pound of cure."

Aflatoxin plays a major role in the development of liver cancer world-wide.

Where does aflatoxin come from?

Fungal infections of crops...

How about a Friday fungal thread?🧵1/
bit.ly/3RuSo7M

https://twitter.com/LancetGastroHep/status/1545337943602102272

>60% of the world's population depends on 3 staple grasses for their food security: Rice, wheat & corn (maize).

It turns out that insects like to eat these cereals for breakfast - a huge problem for small holder farmers.2/

bit.ly/3P9Oq2n

As insects snack, they pick up fungal spores from weeds & soil then spread them from plant to plant.

A double-whammy -

Not only do farmers lose crops to the insects, but the remaining crop gets infected. 3/

weforum.org/agenda/2021/06…

Once the fungus becomes established in the crop, it starts to elaborate mycotoxins - toxic metabolites that cause a range of health problems in humans and animals that consume them.

These toxins are heat stable - they don't break down with cooking.4/

bit.ly/3bNPWIW

Aflatoxin is one of the most potent mycotoxins that contaminates crops & has a very interesting story:

In May of 1960 turkeys in England started dying suddenly & dramatically – at first appearing healthy and then dropping dead.5/

gizmodo.com/the-worlds-mos…

On autopsy, the turkeys livers were found to be necrotic. The source was contaminated peanut meal that glowed under UV light.

This is an example of contaminated maize.6/

The 1st outbreak of human aflatoxicosis was reported in 1975.

The consumption of moldy corn led to an epidemic of sudden liver failure & death in >100 people & dogs.

When one of the liver specimens was examined under UV the tissue glowed.7/

bit.ly/3nMkvl1

Once aflatoxin was identified as the etiologic agent for this disease, officials devised methods to identify contamination & it has become heavily regulated in food crops.

And as if acute liver failure isn't bad enough, aflatoxin turns out to be a potent carcinogen!8/

When aflatoxin is consumed, it's metabolized to a compound that binds to DNA and causes mutations.

Mutations can turn off a gene called P53.

P53 is really important for regulating cell growth.

When turned off, cells can multiply & become malignant.9/

creativemeddoses.com/topics-list/af…

Turns out that aflatoxin may play a causative role in up to 28% of the global burden of liver cancer, accounting for up to 155,000 cases per year!

The risk markedly increases with Hepatitis B or C infections.10/

ehp.niehs.nih.gov/doi/pdf/10.128…

Back to our idea that "An ounce of prevention is worth a pound of cure"....

There are some important interventions that we can make using integrated pest management to prevent aflatoxin contamination of crops & limit human exposure.

Herbicides can be used to control weeds that harbor pathogenic fungi.

Insecticides can control insect pests that introduce fungal infections to crops.

And if those measures are unsuccessful, a fungicide may be used to treat fungal infections and prevent their spread.11/

Even better?

Genetic modification of crops.

Yep - you read that right.

Want to know why? 12/

The story goes back all the way to the beginning of the environmental movement when Rachel Carson wrote her book, "Silent Spring". 13/

The insecticide DDT, which wiped out malaria in the US & Europe was also being used in farming.

The problem was that it was a broad spectrum chemical & not only controlled crop pests, but also harmed beneficial insects.

It also bioaccumulated up the food chain. 14/

Although Rachel Carson was concerned about the off-target effects of DDT, she recognized that for the 1st time ever, farmers had a low-toxicity product that provided great crop protection.

So she made a recommendation that farmers use a natural chemical instead.15/

This natural chemical, made by a bacteria called Bacillus thuringiensis (Bt) targets specific crop pests and is approved for organic farming.

To this day, organic farmers spray it on their crops.

Then scientists got smart & figured out which gene in the made the Bt protein.16/

They isolated the gene & put it in plants.

GMO crops were born.

& hardly needed any insecticides!

They ran multiple studies over multiple decades & demonstrated that GMO crops were as safe as their conventional counterparts.

That was until recently, when they discovered...17/

GMO crops have a "halo effect."

They protect surrounding crops from insects & significantly decrease fungal infections in those crops, too!

No fungi, no aflatoxin.

No aflatoxin = reduced risk of liver cancer.

+ Marked reduction in pesticide use! 18/

foodinsight.org/gmos-have-this…

Moral of the story?

I love GMOs.💕

#ModernAg is critical for #foodsecurity & for #publichealth.

FIN

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