If anything, acute hazard shrank while chronic hazard stayed the same.

I have no clue why this is, but I do find it interesting.

In sweet cherries, we see a completely different pattern.

No bump in insecticide application after SWD introduction.

This dataset is also from Michigan, BTW.

Fun fact: Chlorpyrifos is the 33rd most toxic insecticide that I'm aware of. RfD = 0.0003 mg/kg/day.

It does not take a whole lot of the stuff to kick that chronic hazard quotient up a notch or two.

Not surprising. You handle insect problems with insecticides.

What surprised me was that the acute hazard actually stayed the same for awhile after the introduction of SWD to Michigan.

Chronic hazard spiked, thanks to the increased application of Chlorpyrifos.

So enter cherries, and we're starting with tart cherries.

SWD is a major pest in cherries.

After SWD was detected in Michigan, growers responded by increasing applications of insecticides to their fields.

A really great pest to explore this with is Drosophila suzukii, or SWD.

SWD lays eggs inside ripening fruit, causing the fruit to become unsellable.

SWD was introduced in 2008, and since then has become a $500 million a year pest.

Dermal really would be preferable, but the EPA requires LD50 and RfDs, so they're easy to obtain for all insecticides on record.

There's more than 140 insecticides we put on crops. I have LD50s and RfDs for 142 different AIs, and finding them all was a real trip.

So anyways...

We can define acute hazard as LD50s per hectare, while defining chronic hazard as reference doses (RfD) per hectare.

These numbers aren't perfect. Farmworkers are not out there licking produce in the field, so they're not exposed to pesticides via the oral route.

Enter the reference dose, or the maximum amount of the residue which is allowed on food.

This is often set 1,000x lower than the No Observable Effects Level, which is how much a rat can eat without us being able to detect any difference.

This number is MUCH squishier than LD50 for many reasons.

We can define how hazardous a chemical is using two measurements.

First, oral LD50, which is a measure of acute toxicity. How much of the chemical can a group of rats eat before half of them die?

This is a pretty solid measure of acute risk, but oftentimes, we're interested in chronic risk.

Obviously, if the pest is bad enough to need to be controlled, that means more insecticide applications.

BUT...

Newer chemistries tend to be less toxic to people, so if the response to the new pest is being driven by newer chemistries, then you might expect hazard to go down.

It was originally posted as a 3 part thread, and unfortunately, the 2nd part didn't do too well.

Which is a shame, because we came VERY close to reigniting the civil war over RMSF.

Regardless, the first and third parts are combined here and I think they go together very well.

Also, fun fact: It used to be a white supremecist hashtag used to promote great replacement conspiracy theories.

Now, it's all hymenopterans all the time.

Huge improvement, IMO.

I mean, you're the one reaching out to barely-followed social media accounts sticking up for a guy who got a brain parasite because he eats rancid meat and pretending this is...healthy or something?

My worst day is going to be better than your best.

Yeah, a roided up vaccine denialist is the picture of public health.

Go fuck yourself.