There HAS to be something else, nonpeptidic (endorphins are peptides, peptides are of course just proteins small enough to count the residues by eye, and even a non-chemist knows what happens, at least roughly, to a protein when one might smoke it..just picture a joint of roast beef, if you were to roll one and smoke it...you'd get a lump of carbon and choke your arse half to death), and not HCOOH in these ants if they genuinely cause a high, because as stated, formic acid just isn't psychoactive. I'd have noticed something working with it otherwise, obviously the ants acid concentration, it has to be an aqueous solution rather than 100% or close to it, but even concentrated HCOOH, all it does if breathed in in any quantity that could be fit in say, a bong, of ant bodies, is act as an irritant, toxic in large quantities of course.
And banging it Nagelfar? remember that the formic acid is, in most ants, in the STING??? the apparatus consisting of a modified ovipositor used to...what? because I was under the impression that stings were used to deposit VENOM into a VICTIM? to kill prey within the ants' weight division (for most, although there are ants, mostly primitive ones, the Ponerine type ants, that can punch WAY above their weight, even though the likes of Dinoponera, Paraponera (bullet ants) are up to an inch long, and capable of killing people in the case of multiple stings. Apparently the Ponerine ants generally, native locals will treat them with the kind of respect they would afford to a dangerously venomous snake), and when ant venom isn't used to kill, it is to inflict pain and force the threat to withdraw.
And think about it this way, too. They are known from the sound of it to contain HCOOH. Do you really want to inject acid? even nontoxic acids, like citric hurt like all fuck if one accidentally say, makes a shot of heroin too acidic when converting the base to a shootable form. Ever missed a shot with the PH off on the high side even a little? not pleasant.
Our british native red ants use HCOOH in their stings, AFAIK, (wood ants also deploy formic, but unlike many ants, they spray it, rather than deliver it as an injection, crows deliberately piss off a nest, and then spread their wings, standing back, to be hosed down in the HCOOH spray, apparently loving it, in order to get rid of parasites, just closing their eyes and seemingly blissed out, at least inasmuch as one can tell this of an avian,
Some ants do contain alkaloidal as well as peptidic toxins in their venom though AFAIK, such as the piperidine alkaloid solenopsin from fire ant venom, which in Solenopsis species, is just one alkaloid, there are others present, so its not unreasonable other Hymenopteran venoms contain alkaloids also.
But endorphins (I mean actual endorphins, or other opioid peptides) will NOT survive being smoked. Peptides are often notoriously difficult to administer in a manner that has central effect. Some can be delivered via nasal sprays but often as not, it means either microinjection into specific brain regions such as are to be made subject to the action of the peptide, or injection via the intrathecal route. They use a peptide painkiller, developed from the conotoxins found in the venom of the deadly cone-snails, predatory marine snails with an extensible proboscis adapted to fire a tiny dart, connected to venom-glands and tethered on a line, like a harpoon gun, the darts being highly modified radular teeth. The venom of many is extremely potent, especially in cones that hunt fish, it has to be to prevent the snail being injured by the fast moving fish, or the prey breaking the line the Conus spp. use to reel in their prey, a the few tens or hundreds of microliters of venom delivered by a single dart from some of the large fish-eaters is so potent that that quantity of crude venom is enough to kill 4-6 adult humans, and the effect on fish...shit it is FAST. I've seen videos, of a cone snail taking on a fish much larger than itself, the venom INSTANTLY paralyzed or killed the fish, on contact. Dart penetrated the skin of the fish and it was immobilized or dead instantaneously, as surely as if it had been shot with a handgun bullet to the head. Scientists developed a peptide from Conus venom, marketed as 'ziconotide', brand name 'prialt' that via nonopioidergic pathways is an extremely effective painkiller, something like ten thousand times as powerful as morphine.
Only snag is, orally it would be wiped out by proteases in the GI tract. Via peripheral IV, it won't cross the BBB either, so it has to be delivered via an inplanted pump with a line embedded in the intrathecal space, so it can get to the brain and exert it's effects.
Smoking of course will never be possible with a peptidic drug, they would all simply char to carbon, inorganic nitrogenous, potentially sulfur containing or oxygen containing dross with no more possibility for bioactivity than would a slice of roast beef were someone to leave the sunday roast in the oven for several days and forget it, to come back to a lump of smoking, stinking graphite-like material. The kind of thing you get if you pour concentrated sulfuric acid onto table sugar, causing it to give off stinking smoke, and heat up as the sulfuric strips the water from the sugar molecule, leaving it as a foamy stick or lump of inorganic carbon giving off a sulfurous smell from the SOx released from the exothermically heated H2SO4.
You'd not expect sugar treated thus to taste sweet, would you? and so it is from smoking a peptide. You WILL get no bioactivity. Might as well expect psychoactivity from swallowing a mouthful of water as smoke a peptide.
