Latex Sensitivity
1
A. Christopher Robin wanted Father Christmas to bring him “a big red India rubber ball”; others have a less innocent enthusiasm for the sap of Hevea brasiliensis the rubber tree. But though latex rubber is useful for many purposes, it also carries risks. Some people are highly sensitive to the stuff — so much so that they can die from being exposed to it.
2
B. Nobody knows which or how many of the hundreds of proteins in latex provoke the allergic reactions that natural rubber causes in 1 % of people. But whatever its cause, latex sensitivity is beginning to attract attention. Last week America’s Food and Drug Administration (FDA) joined forces with the Centres for Disease Control and the National Institutes of Health to sponsor an international conference in Baltimore on latex sensitivity. Almost 400 scientists, nurses, doctors and dentists, along with representatives of the rubber industry, turned up. The medical professions use latex a lot; they are well placed to notice adverse reactions and to deal with them.
3
C. Consider as an example the latex cuff used when the bowel is filled with barium and examined with X-rays — a common procedure. That these barium enemas can cause anaphylactic shock, a life-threatening allergic reaction, has been known for decades. What is new is the discovery that the cuff of the enema nozzle can produce this reaction on its own. Of 407 such cases of shock reported to the FDA in the past four years, 15 have been fatal. There may well have been other cases, not recognized as being due to latex sensitivity. The largest manufacturers of the cuffs now make them of a synthetic material.
4
D. Other patients at risk include children with spina bifida, a defect of the spine; these children usually cannot urinate without a catheter, and can face as many as 20 corrective operations before reaching adulthood, so they come into contact with all sorts of medical apparatus that contain latex. And for people predisposed to latex sensitivity, the more frequent and prolonged their exposure, the worse the reaction can become. These days, staff caring for children with spina bifida are aware of the potential for trouble; so precautions are taken to prevent their becoming sensitive to latex and to protect them if sensitized already. Most of the children are operated on in theatres that have been made as latex-free as possible, and none has been lost to shock.
5
E. The danger affects health workers as well as patients. People who need to wear rubber gloves at work are the largest single group at risk, and the AIDS epidemic has greatly increased their number. Doctors, nurses, dental hygienists and laboratory technicians who used to wear gloves only occasionally now find themselves changing them as often as 30 times a day. And the cornstarch with which the gloves are often dusted spreads small amounts of latex all around the place. Some studies have found that as many as 10% of health workers have developed latex-related skin conditions or other allergic reactions. Should they then need an operation, or other medical procedure, entailing exposures to latex, they may run into further complications. Indeed, some sufferers have been so incapacitated by the problem that they have had to change jobs.
6
F. Of course, other people use latex, too. The sensitivity was first noticed in someone using household rubber gloves. It can also afflict the users of condoms or diaphragms. No deaths have been reported in these groups, though, and levels of reaction are quite low. It is worth noting that the remedy for anaphylactic shock is adrenalin.
7
G. Despite the worries, latex is such an exceptional material — nothing else so cheap is such a good, long-lasting barrier, while at the same time allowing tactile sensitivity — that there is no talk of getting rid of it. A better solution is to label products carefully and to screen people for sensitivity. In the longer term, refinements in manufacturing might make the substance less allergenic. Or people could use a different rubber; latex produced from guayule, a shrub which grows exuberantly in America’s south-west, shows signs of having fewer allergens.