Montreal Gazette - - WEEKEND LIFE + WEATHER - JOE SCHWARCZ [email protected] Joe Schwarcz is di­rec­tor of McGill Univer­sity’s Of­fice for Sci­ence & So­ci­ety ( He hosts The Dr. Joe Show on CJAD Ra­dio 800 AM ev­ery Sun­day from 3 to 4 p.m.

The Bri­tish Med­i­cal Jour­nal re­cently re­ported a case of “Car­diac ar­rest by in­hala­tion of de­odor­ant spray.” The cul­prit wasn’t any of the “ac­tive” in­gre­di­ents, but rather the gas used as a pro­pel­lant to ex­pel the con­tents from the con­tainer. Bu­tane can cause car­diac ar­rest when in­haled in an abu­sive fash­ion by peo­ple look­ing for a “high.” Ac­cord­ing to the case re­port, a 19-year old man sprayed de­odor­ant un­der a towel placed over his head and took some deep breaths. They were the last ones he would ever take. Bu­tane is fat-sol­u­ble, which means it can read­ily cross the blood-brain bar­rier, a net­work of cells that pro­tect the brain by ex­clud­ing wa­ter-sol­u­ble sub­stances. Once it en­ters the brain, bu­tane can cause eu­pho­ria, re­lax­ation and an al­tered mental state. But it can also re­sult in a per­ma­nently al­tered state, namely, death. Un­for­tu­nately, the in­hala­tion of volatiles goes be­yond de­odor­ants, with vapours from lighter fluid, nail pol­ish re­mover, shoe pol­ish, com­puter dust spray and glue also be­ing abused. Volatile sub­stances can be in­haled from a bag (bag­ging), di­rectly from a con­tainer (sniff­ing), or by plac­ing a cloth soaked with a chem­i­cal over the nose and mouth (huff­ing). Even sub-lethal ex­po­sure can cause headaches and ver­tigo as well as a feel­ing of light­head­ed­ness. I have been fol­low­ing the rather ex­ten­sive lit­er­a­ture on “in­halants” ever since I had a per­sonal en­counter with the sol­vents used in white­board mark­ers. Al­though I use slides ex­ten­sively in most of my lectures and pub­lic pre­sen­ta­tions, I’ve al­ways found the black­board to be very use­ful when teach­ing or­ganic chem­istry. Chalk dust never both­ered me much, but when white­boards and erasable mark­ers came on the scene, the univer­sity made the switch in a num­ber of lec­ture rooms, sup­pos­edly for a cleaner en­vi­ron­ment. I had no choice but to use the mark­ers. They gave me a headache. Fig­u­ra­tively and lit­er­ally. The mark­ers didn’t erase as well as chalk, and the sweet smell of the sol­vent used to de­liver the ink was nau­se­at­ing. But there was an­other ef­fect. Af­ter a long lec­ture, I found I was pos­i­tively giddy. I had al­ways been high on or­ganic chem­istry, but this was some­thing else. What was this in­tox­i­cat­ing sol­vent? Hav­ing ready ac­cess to a lab and gas chro­matog­ra­phy equip­ment, it wasn’t dif­fi­cult to iden­tify the sol­vent. It turned out to be mostly a mix­ture of xylenes and toluene, chem­i­cals pro­duced from petroleum that have nu­mer­ous uses in in­dus­try. Their ef­fects have been ex­ten­sively stud­ied with nau­sea and headaches doc­u­mented at an ex­po­sure of 100 parts per mil­lion. When con­cen­tra­tions in the air reach over 200 parts per mil­lion, symp­toms in­clude dizzi­ness, ir­ri­tabil­ity, a slowed re­ac­tion time and a feel­ing of be­ing “high.” Long-term oc­cu­pa­tional ex­po­sure has been linked with in­som­nia, tremors, hear­ing loss and a type of brain dam­age re­ferred to as “or­ganic sol­vent syn­drome.” I had no way of de­ter­min­ing ex­actly what my ex­po­sure was, but clearly, it was not in­signif­i­cant. While I was quite happy to write the molec­u­lar struc­ture of xy­lene on the board and elab­o­rate on its chem­i­cal re­ac­tions, I had no de­sire to in­hale it. I lob­bied to get the black­boards back, and when our main chem­istry lec­ture theatre was ren­o­vated, the white­boards were gone, and the good old black­boards had made a tri­umphant re­turn. And they came equipped with “dust­less” cal­cium car­bon­ate chalk that re­placed the “dusty” ones made of cal­cium sul­phate. Frankly, the dusty ones are bet­ter, but nei­ther gives me a headache or a high. Sup­pos­edly, xy­lene and toluene are no longer used in dry erase mark­ers, hav­ing been re­placed by the safer iso­propanol, bet­ter known as rub­bing al­co­hol. The xy­lene ex­pe­ri­ence did send me scur­ry­ing to look more deeply into “or­ganic sol­vent syn­drome” and I learned all about the prac­tice of sniff­ing model air­plane glue, cor­rec­tion fluid, spray paint, cook­ware coat­ing sprays, gaso­line, felt-tip mark­ers, hair­spray, de­odor­ants and amaz­ingly, cow dung. Some thrill seek­ers even try spray­ing bu­tane straight from a can­is­ter down their throat. This can lead to a nasty sur­prise be­cause as liq­uid bu­tane evap­o­rates, it sucks heat from the sur­round­ings, po­ten­tially freez­ing tis­sues in the throat and in the lungs with pos­si­ble per­ma­nent dam­age. At least with cow dung, this prob­lem doesn’t arise. Al­though we don’t have much of this com­mod­ity ly­ing around our streets, in Malaysia ap­par­ently there is ready ac­cess. Some young Malaysians have dis­cov­ered that sniff­ing the meth­ane re­leased from a fresh sam­ple of cow dung af­fords a plea­sur­able ex­pe­ri­ence. The tech­nique in­volves plac­ing a tin can with a hole punched in the top over a sam­ple of the dung and in­hal­ing. Bad idea. An even worse idea is to light a cig­a­rette in a car that has been filled with bu­tane vapour, as a num­ber of eu­pho­ria-seek­ing young men have dis­cov­ered. Bu­tane is ex­tremely flammable! There isn’t much eu­pho­ria to be ex­pe­ri­enced in the emer­gency room.

Dario ayala

A worker ap­ply­ing spray paint wears pro­tec­tive equip­ment. Un­pro­tected oc­cu­pa­tional ex­po­sure to sol­vents com­monly found in spray paints and many other prod­ucts can cause se­ri­ous health problems, Joe Schwarcz says.


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