Toluene–a hydrocarbon which is present in gasoline, paint thinners, and many industrial solvents–can have a variety of effects on acid-base metabolism by the kidney: it can cause both a non-anion gap OR an anion gap metabolic acidosis, depending on whether or not the exposure is acute or chronic.
The most well-described with chronic or repeated exposure–as might be seen in a patient who has the unhealthy habit of glue sniffing, or “huffing”–is a renal tubular acidosis, resulting in a non-anion gap metabolic acidosis and hypokalemia. Multiple case reports support the existence of both distal and proximal RTAs with toluene exposure.
However, acute toluene exposure can also lead to an anion gap. This is because the major byproduct of toluene breakdown by the liver’s cytochrome p-450 system is hippuric acid, which is an (unmeasured) organic acid.
This is why your 1st-grade teacher told you to stop sniffing the glue.