"Like snapping at flies": the rubber librarian hears from the condom makers

Once again Winnipeg is experiencing that most rigorous of winter's many onslaughts, a cold snap. It's so cold there's an air of conspiracy about it, because it doesn't seem real. On the other side of my frosted-up window it's as cold as a campground privy on the dark side of Pluto. Lip-crinkling, flesh-withering, molecule-slowing winds that seem to have blown across the vacuum of space before reaching us, testing the lower depths of the Kelvin scale. With weather like this it is perhaps appropriate to return to the troubling question that has concerned the public health authorities here. What effect does Winnipeg's cold weather have on latex condoms?

I have an update to my two previous posts about this issue. In my last post I reported on the initial response from the condom manufacturer to the question whether condoms can be stored safely in the cold.

Here is that first reply that came to public health officials:

Latex condoms are made of natural polyisoprene, 99+%, with trace amounts of residual vulcanization chemicals. This is a stable organic polymer and contains no water. As well, there are no mixtures or emulsions. As such, there is nothing in a latex condom to be affected by cold temperatures. Indeed, a sealed, opaque packaged condom place [sic] in a cold environment may well be preserved.

Problems may occur in the thawing process if extra heat is added. Should condoms freeze, they must be left to thaw gradually at room temperature.

A follow-up email was sent to the company asking why, if this is the case, cartons of condoms purchased in bulk bear printed instructions not to store their contents in extreme heat or cold. The carton warning reads: "Store at room temperature. Protect latex condoms against prolonged periods of exposure to: extreme low or high temperatures, moisture, direct sunlight, fluorescent light."

There certainly is sufficient research to support all the other warnings. But the fruitless search I did for the Healthy Sexuality and Harm Reduction department of the Winnipeg Regional Health Authority showed that the risk of extreme cold to the physical integrity of the condoms is still unknown. Yet we have a printed warning about exposure to extreme cold printed on every box of condoms manufactured in a southern American state where cold normally means how you like your tea. The cryogenic frigidity of a Prairie winter is not even conceivable where these condoms are made. One begins to juggle with the questions that pop up. What, then, would warrant the printed warning on the condom packages? What exactly is the nature of the risk so obliquely referred to. Is it a risk to the plastic wrap or the condom lubricant? What rationale, we must ask the manufacturers, is there for this warning?

Perhaps this left them with too many balls in the air, for it was only after a considerable delay that a reply was finally received from a spokesperson:

Please forgive the delay in responding to your inquiry but I took the time to review it with the regulatory officials in case anything had changed since my last investigation into this matter.

The warning against prolonged cold is just a precaution. There is nothing about cold that will harm the latex as long as the condoms are thawed before use. Extreme cold can make latex hard and brittle, just as it does many items. We have no literature references immediately at hand for you on this subject, but we have tested frozen condoms in the past and we have laboratory data to sustain this claim [data not supplied].

The warning against prolonged heat and light exposure is NOT just a precaution. Both will shorten the life of condoms and ultimately destroy them. Heat is used in accelerated aging protocols. A [sic] opened condom exposed to light will be compromised in a [sic] little as a week. As you mentioned, there is literature available to sustain this claim.

The moisture warning is for the boxes and film only as moisture has no impact on the condom itself. The box, however must remain intact to help protect against light and temperature fluctuation.

Plastic wrap for condoms is fine for the shelf life of condoms, as long as the seals are intact. There is absolutely no cause for concern regarding the plastic film.

Films and especially seems [sic] can suffer water damage. Condoms that have been flooded could be compromised if the seems [sic] of the films or foils are not intact or have been damaged and water may have infiltrated. Again, we have no literature references immediately at hand for you on this subject but such incidences have occurred.

I regret that I am unable to provide the literature you were hoping to receive. Until Health Canada mandates manufacturers to test for these specific issues, I doubt that any such literature will be made available.

Speaking out of both sides of their mouth and saving both their faces, the condom manufacturers claim to have "tested frozen condoms in the past." But at present they "have no literature references immediately at hand" on this subject. At the same time, they do have "laboratory data to sustain this claim." However, they are unable "to provide the literature you were hoping to receive." The warning against prolonged cold is "just a precaution" they tell us. (Against what?) And they will take no steps to release existing data, conduct any further research, or answer any more questions about this matter unless forced to by government regulators.

As a society we place a great deal of trust in manufacturers of products designed to keep us and our children safe. One would think that a respected condom manufacturer would have resorted to keeping fewer balls in the air and taken slightly more time and effort to respond to an honest question from a public health official. Why not condescend to show some interest in what is after all an interesting and challenging query? To start with, why not share the so-called laboratory data? Who are the "regulatory officials" who were consulted? Why no promise of cooperation in referring the question to Health Canada? Trying to get a decent answer from Condoms & Co. is like snapping at flies. The answer we finally get leaves such a bad taste, it's like we actually swallowed one.

Note: The opinions stated in this post are entirely my own and do not necessarily represent those of the Winnipeg Regional Health Authority.

Stiffening in the cold: more on condoms in the Canadian winter

"The elastomers—natural rubber and polychloroprene— ... are susceptible to crystallization during prolonged exposure to low temperatures. This leads to a gradual long-term stiffening. ... Stress–strain measurements have confirmed the extremely large increase (up to 100-fold) in the initial stiffness that crystallization produces." (Fuller KNG, et al. The effect of low-temperature crystallization on the mechanical behavior of rubber. Journal of polymer science: Part B: Polymer physics. 2004;42:2181-90.)


The rubber librarian has been at it again, straining hard to stretch a bit more evidence over a vast gap in the condom literature. Last month I posted on my failure to find any scientific literature on the effect of extreme cold on latex condoms. But the thrust of my investigation didn't stop there. Not trusting my own abilities to probe the strange literature of latex, I consulted with a colleague in the Sciences and Technology Library who knows well the ins and outs of the relevant databases, just to make sure that I hadn't missed anything vital. After a prolonged search he found a number of seminal papers on the influence of low-temperature crystallization on the tensile elastic modulus of natural rubber. My enthusiasm for the subject momentarily bounced back, until I realized that once again the condom was getting no respect. All that rubber research and not one mention of condoms. Undeflated however, I carried on. Here is a brief survey of the science of gelid latex, and anything useful pertaining to condoms that can be extracted from this small body of knowledge. A full bibliography with abstracts is given below as an appendage.

To get any insight into what "tensile elastic modulus" exactly means, think stretchability or "elongatability." Modulus is a mathematical term that was appropriated by the British scientist Thomas Young in the 18th century to express the physical measure of stiffness, equalling the ratio of applied load (stress) to the resultant deformation of the material, such as elasticity or shear. (A high modulus indicates a stiff material.) Having thus stretched my high school chemistry to the snapping point by reading through a torrent of exceedingly dull prose, I finally reached a partial understanding of inspissation and cold crystallization and their effect on tensile elastic modulus. To avoid undue rigidity of language, let us translate this jargon-splotched no-man's-land of technolinguistic barbed wire and chevaux-de-frises into a more flexible dube-ological vernacular (kondomswissenschaftliche Umgangssprache). The upshot of seventy years of low-temperature rubber research is that it gets hard in the cold. The non-scientific majority of humanity must be truly grateful for this remarkable advance in rubber research.

What does this all mean for the hardy condom user? Because cold tends to "crystallize" rubber, this leads to a progressive increase in density, gradual long-term stiffening, and a doubling of tensile elastic modulus ... of the condom, not its wearer. None of the literature discovered by my research actually concerns itself with the common condom, but all the science points to a Canadian winter's ability to make rubbers slightly brittle, which could possibly — and I emphasize possibly — lead to leaking or breakage. Not to elongate this explanation more than the kinetic measurements allow, it seems clear that the effect of arctic air on a condom's stress-strain characteristics, in reverse proportion to its effect on the body part for which the condom is designed, is one of stiffening and tensile swelling. Furthermore, as Natarajan cogently reminds us [6], free radicals formed during tensile testing at low temperatures are stable below the glass transition temperature of the material. (These radicals arise from main-chain fracture occurring during yielding of the material — and too-frequent reading of Bakunin in unheated garrets. Natarajan also suggests that yielding of the material which gives rise to these characteristics occurs by crazing of the material — reading Bakunin in an unheated garret during a Winnipeg winter.)

The existing research suggests that public health officials might consider ensuring that condoms for distribution by clinics and street health workers are not stored at extreme winter temperatures. Individuals should not keep their condoms in glove compartments, unheated back porches, or hidden behind the snow blower in the garage. Most package directions already recommend a normal range of acceptable temperatures for safe storage. Maybe they are right.

A condom manufacturing company with whom my local health authority has dealings responded by email to an official request for their position on condom storage. The company's reply stated that in their opinion there is no risk in storing condoms in extreme cold, as long as they are not thawed out with the application of high heat, but are allowed to come gradually to a normal temperature. A follow-up email was sent to the company asking why, this being the case, large boxes bought at wholesale containing hundreds of condoms have printed instructions not to store their contents in extreme heat or cold. To date no reply has been received. This anecdote is no proof that condom manufacturers have no answers, but it does demonstrate how the lack of research on this issue means that the concerns of public health departments cannot be resolved by resorting to corporate public relations offices.

Other questions come to mind. Even if the storage of condoms in extremely cold environments, caeteris paribus, has no effect on their integrity, what guarantee is there that the cold would never contribute to damage caused by the often imperfect conditions that pertain in warehouses? What if, for example, a large box full of condoms were dropped from a truck or a fork lift at a temperature well below zero, or were otherwise jostled, jounced or dented? Might the cold, having stiffened the latex, not contribute further to any resulting damage to individual condoms? Is it possible that the increased modulus and crystallization of the latex might contribute to minute tears that could cause leakage or breakage when the condom is eventually used? What is the effect of extremely low humidity and excessive cold on condom integrity? Could this combination further contribute to damage from being bumped or dropped in storage?

This will have to be our last word for now on condoms and low temperatures, until a free radical bounces upon the scene to answer all our questions, electrify the rubber world, and warm the hearts of Canadian street health workers with a path-breaking, definitive study.


Flecte quod est rigidum,
Fove quod est frigidum,
Rege quod est devium.

Bend what is stiff,
Warm what is cold,
Guide what goes off the road.

Archbishop Stephen Langton, d. 1228

References:

1. Specifying elastomers for low temperature service. Materials and methods. 1953 Nov;38(5):114-8.
Changes occurring in rubbers as result of exposure to low temperature; how common elastomers differ in their low temperature behavior; improvements in low temperature flexibility obtained by use of certain types of plasticizers in compound; chart shows minimum temperatures at which various elastomers are useful.

2. Chenal JM, Chazeau L, Bomal Y, Gauthier C. New insights into the cold crystallization of filled natural rubber. Journal of Polymer Science, Part B: Polymer Physics. 2007 Apr;45(8):955-62.
This article is devoted to the cold crystallization of filled natural rubber with different types of filler such as carbon black, silica, and grafted silica. A large set of differential scanning calorimetry data is presented with various scanning rates, times, and temperatures of isothermal crystallization to display the factors affecting natural rubber (NR) crystallization. The crystallization kinetic measurements suggest that fillers can create a region with perturbed mobility where the kinetics of nucleation and/or growth are slowed down, the rest of the matrix being unperturbed. And, the final crystallization level indicates the existence of an excluded region for crystallization close to the filler surface. Furthermore, the presence of fillers appears less unfavorable to NR crystallization than chemical crosslinking.

3. Douglas WD. Mechanical properties of rubber in compression at low temperature. India rubber journal. 1930 Dec;80(25):9-11.
Investigation on effect of low temperatures on stress-strain characteristics of rubber in compression; tests were made upon half-inch cubes of black rubber of specific gravity 1.3 cut from single molded ring, such as might be used in springing of aircraft tail skids.

4. Fuller KNG, Gough J, Thomas AG. The effect of low-temperature crystallization on the mechanical behavior of rubber. Journal of polymer science: Part B: Polymer physics. 2004;42:2181-90.
In cold climates the correct performance of rubber components such as seismic isolators depends on them maintaining their elastic properties when exposed to prolonged periods at low temperatures. The high damping compounds developed for seismic isolation are normally especially prone to crystallization when exposed to subzero temperatures for periods of a few weeks. The effect of low-temperature crystallization on the mechanical stiffening of natural rubber is evaluated. The relationship between the shear modulus and amount of crystallization is measured using a technique in which the dimensional change and stiffness are monitored simultaneously. The relationship is found to be approximately independent of the crosslink density and the temperature of crystallization. It appears not to be realistically modeled by considering the crystals to behave as rigid filler particles but good qualitative agreement with experiment was obtained by modeling the crystals as a network of threads. Partially crystalline rubbers are found to yield under the application of a large stress like other partially crystalline polymers. Mechanisms for suppressing crystallization in rubber are discussed and the low-temperature stiffening of specially formulated rubber compounds for seismic isolation is presented. These results show that carefully formulated high damping natural rubber compounds can give adequate performance at low temperatures.

5. Ho CC, Khew MC. Low glass transition temperature (Tg) rubber latex film formation studied by atomic force microscopy. Langmuir. 2000;16(6):2436-49.
Latex with very low glass transition temperature (Tg) polymers forms a continuous film on drying. The physical and mechanical properties of the film are dependent on the extent the latex particles are able to coalesce and fuse into each other. Any hindrance to the film formation process would result in a poorly formed film and a drop in performance. The film formation process of natural rubbert (Tg approx. -65C) latexes and synthetic latexes with low Tg are monitored as a function of time using atomic force microscopy (AFM). The influence of the leaching method of the film, the presence of additives (some added after preparation) and nonrubber materials [specific for natural rubber (NR) latex only], and gel content on film morphology and flattening of the particles in the film is studied. The influence of the leaching procedure on the effectiveness of nonrubber removal from NR latex films and their effect on film formation is highlighted. The effects of nonrubbers and high gel content of NR latex in slowing down the NR film formation is discussed and contrasted with the synthetic polyisoprene and chloroprene latexes. The change of the surface mean roughness, Ra, with time provides a convenient means of comparing the rate of flattening of the polydisperse particles in these films.

6. Natarajan R, Reed PE. Molecular fracture in natural rubber during tensile testing at low temperatures. Journal of Polymer Science, Macromolecular Reviews. 1972 Apr;10(4):585-98. Sulfur-cured natural rubber and other elastomers subjected to tensile tests at low temperatures and low strain rates are found to swell and left double quote foam right double quote after testing when brought to room temperature. Free radicals formed during tensile testing are studied by (ESR) techniques. It is found that the free radicals observed at the low temperatures are stable below the glass transition temperature of the material, and it is suggested that these radicals arise from main-chain fracture occurring during yielding of the material. It is also suggested that yielding of the material which gives rise to these characteristics occurs by crazing of the material.

7. Spanos P. Cure system effect on low temperature dynamic shear modulus of natural rubber. Rubber world. 2003 Nov;229(2):22-7.
The effects of cure system on low temperature properties of natural rubber are discussed. High crosslink density cure systems were used for minimizing the crystallization induced shear modulus increase at low temperatures. Modulus measurements were made using dual lap shear samples on a servohydraulic dynamic test machine. The results show that the most pronounced changes in modulus occurred with the lowest sulfur formulation. All of the modified cure systems showed a much smaller change in modulus with decreasing temperature.

8. Stevenson A. Crystallization stiffening of rubber vulcanizates at low environmental temperatures. Kautschuk und Gummi Kunststoffe. 1984 Feb;37(2):105-9.
In environments with low ambient temperatures, several types of rubber vulcanizate can stiffen due to the formation of a crystallite structure in the rubber. The elastic modulus can increase by up to two orders of magnitude. The paper discusses the relevance of the stiffness changes to the performance of various rubber engineering components in cold environments - e. g. bridge bearings, helicopter rotor bearings and offshore mooring bearings. The stiffening of several natural rubber and polychloroprene vulcanizates, specified for engineering applications, has been studied at temperatures from minus 40 degree C to plus 5 degree C, using direct measurements of elastic modulus. The paper also reports on the correlation between changes in elastic modulus and results from the existing standard (ISO) tests - low temperature compression set and low temperature hardness.

9. Stevenson A. Influence of low-temperature crystallization on the tensile elastic modulus of natural rubber. Journal of Polymer Science, Polymer Physics Edition. 1983 Apr;21(4):553-72.
Data are presented which show that when natural rubber crystallizes at low temperatures, there is an increase in elastic modulus of up to two orders of magnitude. This phenomenon has beens studied at various temperatures in the range 0 to minus 55 degree C for samples held at tensile strains of up to 500%. There is an induction period associated with the nucleation of crystallites, before any increase in modulus is observed. The induction period increases with decreasing strain and passes through a minimum with increasing temperature at minus 25 degree C. The growth rate subsequent to nucleation is successfully described in terms of Avrami-type rate relationships. The Avrami rate coefficient is independent of temperature and follows a simple exponential function of strain. The equilibrium extent of the modulus incease has also been studied by means of experiments of up to three months' duration. The equilibrium modulus increases with decreasing temperature - as predicted by Flory's thermodynamic theory.

10. Yu HQ, Liu, XH. [Study on shear properties of low-temperature modified nature rubber]. Guti Huojian Jishu/Journal of Solid Rocket Technology. 2006 Jun;29(3):222-4. Chinese.
Compared with the relationship between shear strength and strain of nature rubber, the shear properties of the low-temperature modified nature rubber at -30-50C. was investigated. The analysis results show that the shear modulus of the low-temperature modified nature rubber kept for 6 hours at -30C or 50C is close to shear modulus at room-temperature when the shear stress is up to 343 N. Furthermore, the adhesive quality of the modified nature rubber with metals and other composite materials is very good, which can meet the adhesive strength demand of component in the temperature range -30-50C.

Pushing tobacco on the web: is YouTube telling or selling you something?

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Ask the rubber librarian: what happens to condoms in a cold snap?

Talk of your cold! through the parka's fold it stabbed like a driven nail.
— Robert Service, The Cremation of Sam McGee

It's a bit of a stretch calling myself a rubber librarian, although I feel I can make some modest claim to the title. As a student I once endured an excruciating presentation on "Rubber Librarianship" given with a straight face by the corporate librarian at Goodyear, who was so completely devoid of a sense of humour that she banged on in earnest about "rubber research" and "rubber bibliography" over the unsuppressible tittering of my classmates. As fate would have it, I now find myself acting as the unofficial information specialist for Winnipeg public health workers; so I have to know the latest on latex and other prophylactic materials. One has to be flexible you know. Last August a by-the-way question led me to a lengthy search on the efficacy of plastic wrap for oral sex. The outcome? It isn't and you probably shouldn't, but it's better than nothing, especially if you're in prison. Last week I was given another stumper: Do condoms retain their integrity when shipped or stored in extremely cold temperatures?

This is not a frivolous question. This is Winnipeg in wintertime. Like Bratsk, Irkutsk and Krasnoyarsk, Winnipeg is in the running to be The World's Coldest City. This year I think we're winning. Plunked down on flat parkland at the edge of the boreal vastness, we are a congealed place of block heaters and balaclavas, frost bite and flannel sheets. For nearly a month now we have experienced what is appropriately called an "Arctic outbreak," a dome of fiercely frigid air that squats on the middle of North America like an invisible glacier. The result: intense cold — blubber-cracking, tooth-splitting cold. The slightest breeze is a scimitar slicing through the sinuses, trees crack like gunfire, and the hard snow crunches loudly underfoot. Similes and metaphors barely suffice: So cold the wolves are eating the sheep just for the wool. Cold as a sled-dog's snout. Cold as a cocked trigger. Cold as a cruise missile. Cold as a bailiff's heart. A cold so brutal the liquid crystal displays on parking metres wink out, neon signs fade to a sickly glimmer, iPods sputter and die, and cars start, if they start at all, with a juddering, cranking lurch. Even teenagers are known to zip up their jackets and thrust their hands further into their jeans.

So when we ask about the viability of condoms stored in sub-zero temperatures we're not just whistling Dixie. They are still our best defence against STIs. If leaving condoms in the cold degrades their quality, this is something people should know about. So I started my rubber literature search confident that the answer was out there. Unfortunately, like my fruitless investigations into cling wrap, I found virtually nothing on my topic. I pressed on, plumbing the depths of dube-ology, with little to show for it.

There was much technical analysis of the viscoelastic properties of polymers, time-temperature superposition, inspissation, diffusion-limited oxidation, thermogravimetry, Arrhenius behaviour, degradation parameters, tensile elongation, modulus, density, and decay compressive force. In these forbidding thickets of jargon I think I gained a basic understanding that extreme temperatures are bad for condoms, as is air, especially polluted air (3). Condoms should be packaged in impermeable, flexible aluminium foil packaging with a recommended minimum thickness of 8 micrometres (6,9). There are several studies on condom storage in excessive heat (1,2,5,6,7). Research has demonstrated, so says the World Health Organization, that properly packaged, good-quality condoms do not deteriorate when stored at average temperatures found in tropical climates. Air conditioning is not necessary if the condoms are properly packaged and stored in a clean, dry, well-ventilated environment. They must not come into contact with oil, petrol, water or ultraviolet light (9).

About condoms in the cold, however, the literature is silent, except for a 16-year-old article in German on the safety of condoms in outdoor vending machines (4), which I have not been able to obtain. Even if it turns up, I can't be sure its findings would be relevant to the daunting conditions of a Canadian winter. The best that authorities can say is that research is continuing to find better ways to predict accurately the stability of a condom as it ages (8).

Chapter 5 of the online monograph on latex condoms by McNeill et al. (8) offers a useful description of how variations in temperature might affect condoms:

Latex rubber is known as a "viscoelastic" material; i.e., it has a "viscous" or damping component and an "elastic" or springy component. . . . The response of these components changes with the frequency of vibration and with temperature. For example, the children's toy called Silly Putty, which is a silicone rubber, becomes solid if it is very cold but flows under its own weight in a warm room. If pulled quickly, it fractures; if pulled slowly, it stretches. Analogous phenomena occur in latex rubber.

In Winterpeg, in a cold snap, no one in their right mind is going to try playing with Silly Putty outside. The same goes for condoms. But if you watch the cars creeping through the freezing exhaust fog at Portage and Main, you can bet that many of them will have a few condoms stashed in the glove compartment. Probably not a good idea. But having diligently applied all my rubber learning to the matter of how condoms fare in extreme cold, I regret to say I can produce little more than a few undocumented warnings. Canadiancondom.com advises against prolonged storage of its products in temperatures above or below 15-30 degrees Celsius. Similar instructions can be found on manufacturers' websites and on packages on the store shelf. Here is a piece of advice from Go Ask Alice:

Question: I'm not wrong when I say condoms can freeze, right? I had some condoms in my car when the temperature outside was definitely below freezing. They were only out in the cold for about thirty minutes. Would it be safe to still use them? Or, should I discard the condoms and get new ones. The box says to keep it below 100-degree temperature, but doesn't say anything about keeping them above a certain temperature. Safe or not?

Answer: The condoms in your car are probably okay to use considering the brief period of time (thirty minutes) they were out in the freezing cold. For longer-term condom storage, keep them in a regulated and constant environment. Ideally, condoms need to be kept in a cool, dry storage space, and away from direct sunlight, to prevent deterioration. Think of certain fruits and vegetables — once they are frozen or cooked, their texture and consistency are permanently changed. The same holds true for condoms. If they've been exposed to a very cold or a very hot climate long enough to freeze or heat up, then cut them in half (so that no one else can use them) and throw them away. Why? After spending a considerable amount of time in these temperature extremes, latex can become brittle, weakening it as a form of adequate protection against pregnancy and most sexually transmitted diseases (STDs). When warmed up or cooled down to room temperature, even if they look okay, these condoms will be less resilient and effective than before.

So take it from Alice: don't hide your condoms in the freezer, under the hookah in the back porch, or in your glove compartment during a Winnipeg winter.

In a frosty December on the Canadian Prairies you can almost feel the planet's uncaring tilt away from warmth. The poor sun can barely lift itself past eye level before dropping out of sight behind smoking chimneys and brittle trees. The remorseless winds empty out the streets, leaving only hunched smokers shivering and stomping in doorways. During this festive time of tipsy indiscretions at office parties and family fisticuffs over the placement of decorations, Winnipeggers brave the unreal cold to go shopping, elbowing their way through hangar-sized emporiums for trinkets and treats, while the latest tattooed crooner roasts chestnuts from scratchy loudspeakers. In one of these mega-stores — was it Krazy Keester's, or Frostco, or The Haggle Hutch? — I attracted not a few cold stares as I rummaged through condom packages squinting at the storage instructions. The rubber librarian gets no respect.


References:

1. Bo MC, Gerofi PJ, Visconte LLY, Nunes RCR. Prediction of shelf life of natural rubber male condoms—a necessity. Polymer testing. 2007 May;26(3):306-14.

2. Bo MC, Lopes L, Visconte LLY, Nunes RCR. Thermal degradation of natural rubber male condoms. Macromolecular symposia, 245-246. 2006:668-76.

3. Clark LJ, Sherwin RP, Baker RF. Latex condom deterioration accelerated by environmental factors: I. Ozone. Contraception 1989 Mar;39(3):245-51

4. Dahmen HG. [Storage and safety of condoms with reference to the effect of high and low temperatures—dispensers in the open]. Lagerfähigkeit und Sicherheit von Kondomen im Hinblick auf die Einwirkung hoher und niedriger Temperaturen - Automaten im Freien. Offentl Gesundheitswes. 1991 Feb;53(2):97-8. [Note: Article in German. The title as translated in the Scopus database has "outside slot machines" instead of "dispensers in the open." The term should be translated as "outdoor vending machines." I was unable to review the text of this article.]

5. Free MJ, Srisamang V, Vail J, Mercer D, Kotz R, Marlowe DE. Latex rubber condoms: predicting and extending shelf life. Contraception 1996 Apr;53(4):221-9

6. Free MJ, Hutchings J, Lubis F, Natakusumah R. An assessment of burst strength distribution data for monitoring quality of condom stocks in developing countries. Contraception 1986 Mar;33(3):285-99

7. Guigon P, Breton D, Mendes-Oustric AC, Pech A, Clair P. [In vitro studies of factors possibly influencing the performance of latex condoms]. Etude en laboratoire de facteurs pouvant influencer la qualité des préservatifs masculins. Med Trop (Mars) 2005 Nov;65(6):575-9

8. McNeill ET, et al. The Latex Condom: Recent Advances, Future Directions [Internet]. Family Health International; 2006. [cited 8 Dec 2007]. Available from: http://fhi.org/en/RH/Pubs/booksReports/latexcondom/index.htm

9. World Health Organization. The male latex condom: specification and guidelines for condom procurement : 2003. Geneva: Dept. of Reproductive Health and Research, Family and Community Health, World Health Organization; 2004.

The Street Health Report 2007

Fifteen years ago a report on Toronto's homeless was published by Street Health, a community-based health care organization working with homeless and under-housed people in the city's downtown area. The first of its kind in North America, the 1992 report's gruesome statistics revealed a pattern of increased health risk, poor access to health care, exposure to violence, and general despair. The intervening years have been nothing short of brutal for homeless people, although the means have existed to improve their situation. While the exact number of street dwellers has been difficult to estimate, the current estimate is that about 6,500 people slept in shelters last year on any given night, a tripling of the homeless population since the early 1990s.

Released in September, Street Health Report 2007 presents the latest findings on the state of homeless adults in Toronto. The study was conducted in the winter of 2006/2007. There are few surprises. The news is terrible:

Overall, homeless people in Toronto have much poorer health than the general population. Homeless people in our survey carry an alarmingly higher burden of many serious physical and mental health conditions. Three quarters suffer from at least one chronic or ongoing physical health condition. In the past year, more than half had experienced serious depression and one in ten had attempted suicide.

The health of homeless people in Toronto has deteriorated in the past 15 years. Many serious physical health problems have become more common, and new illnesses have emerged that disproportionately affect homeless people. The most important factors impacting the health of homeless people are the result of social policy decisions that have been made by our governments in the past 15 years, particularly the cuts to social assistance and the lack of investment in new affordable social housing.

Homelessness is a devastating and growing problem in Toronto. There is an urgent need to take action to:

• Address the poverty and inequality that underlies homelessness

• Improve access to affordable and appropriate housing

• Improve immediate living conditions for homeless people

• Improve access to health care and support for homeless people

Quoted in a Toronto Star article, Kathy Hardill, outreach nurse and an author of the original study, says the decreased access to health care is one of the study's most shocking findings — especially given the prevalence of disease and disability among Toronto's homeless. Diabetes has increased threefold since 1992; 43 per cent have arthritis, up from 29.8 per cent; and 23 per cent have hepatitis C. In a brief news article, the CMAJ (6 Nov 2007) comments: "It paints a grim picture."

The Street Health Report concludes with an action plan consisting of realistic solutions to immediately improve the health of homeless people and to ultimately end homelessness. Among its 13 recommendations:

• Increase social assistance rates;
• Raise the minimum wage to $10 per hour immediately;
• Increase the availability of affordable housing as soon as possible.
  

The Street Health Report 2007 is available in PDF format from the Street Health website: http://www.streethealth.ca

Expressive liberty

When freedom is outlawed only outlaws will be free.

Having just written a post on homelessness in Canada I was very interested to come across The expressive liberty of beggars, a new study released by the Canadian Centre for Policy Analysis, which claims that restrictions on peaceful panhandling, such as those found in the bylaws of many cities, constitute an illegitimate use of state power.

The 28-page paper, by Arthur Shafer, director of the Centre for Professional and Applied Ethics at the University of Manitoba, says there is no moral or legal justification for turning peaceful beggars into criminals. Shafer does not fail to connect the dots between poverty, homelessness and health. "Panhandlers communicate — whether through speech or via an outstretched hand and raggedy appearance — a message about dire poverty, unemployment, substance abuse, mental illness, and homelessness" (p. 9). More poignant than any manifesto, the visible presence of the poor and homeless defines the issues and demands that things must change. For more information, see the CCPA press release.

Here is the introduction:

It is morally perplexing that in 21st century Canada it could be a punishable offence for one person to say to another, peacefully, in a public place, “I’m in trouble and need help.” Yet that is the effect of City of Winnipeg Bylaw No. 128/2005. Other Canadian and American cities have enacted similar legislation, and a fast-growing body of jurisprudence in both Canada and America testifies to the fact that the criminalization of panhandling has become a kind of battleground. On this battleground, a clash occurs between competing values: social “hygiene” vs. freedom of expression; middle class discomfort vs. underclass economic need; commercial interest of downtown business owners vs. beggars’ right to plead for subsistence.

Of course, if a panhandler’s request for help were made in an aggressive or intimidating manner, then liberty-limiting legislation would be much less controversial. In Canada, the Criminal Code expressly prohibits demanding money with menaces. This prohibition, backed by sanctions, would be accepted by most people as a proper use of coercive state power.

The essence of the argument advanced in this report will be that restrictions of peaceful panhandling constitute an illegitimate use of state power.

Put simply, my contention is that peaceful beggars should not be turned into criminals. That’s because non-aggressive begging involves the kind of expressive communication between people that a free and democratic society should seek to protect rather than restrict. Freedom of expression is a fundamental human right — one that should be infringed only in exceptional circumstances. It follows that any law which restricts the expressive liberty of beggars should be viewed prima facie as a violation of human rights.

There is a substantial body of empirical evidence in support of the intuitively obvious hypothesis that beggars are a seriously marginalized group in our society: almost always poor and frequently homeless, often suffering from extremely poor health, mental illness, and alcohol or drug addictions, with few social supports and even fewer opportunities to make their plight known to their fellow citizens. For this reason, it is comparatively easy to adopt a “we/they” perspective on issues involving panhandlers — a perspective in which “we’ are the legitimate members of society while “they” are little better than social outcasts. Quite simply, this perspective is not ethically defensible. Panhandlers have as much right as middle-class citizens to dignified treatment. The very sub-title of this paper, with its sharp dichotomy between “them” and “us,” runs the risk of conveying, inadvertently, the message that beggars are mere specimens, pinned and wriggling on a hook, rather than participants in the project we call building Canadian society.

If members of the underclass are not recognized as having an important contribution to make to the formation of public opinion, then not only are they robbed of a basic right of citizenship, but everyone else in society is also robbed of potentially important information. Some would argue that the very poor have an especially important contribution to make to the so-called free marketplace of ideas. Critical scrutiny of ideas is an enterprise that requires the widest possible contribution from those with differing experiences and alternative perspectives. When the expressive liberty of the poor and homeless is censored, excluded, or otherwise marginalized, then the advancement of knowledge for everyone is prejudicially affected.
Autonomous citizens should not easily settle for such a limitation on their ability to formulate for themselves their view on such matters.

Indeed, the beggar’s generally downtrodden position in society makes a denial of his expressive liberty especially problematical. Since the free marketplace of ideas (like the free marketplace of commodities) tends to produce massive inequalities in access to expressive forums, special heed must be paid to the expressive needs of those who cannot easily make their voices heard. A liberal democratic society which values the rational autonomy of all its members must work diligently to protect norms of mutual recognition and respect in communication.

It is also worth noting that in Canada panhandlers tend to be recruited, disproportionately, from First Nations’ communities and from the ranks of other visible minorities. In consequence of the racial and other prejudice still widespread in Canadian society, it is common for members of these communities to have suffered serious discrimination in education, housing, employment, and other spheres of life. Drastic inequalities in life opportunities for First Nations people and visible minorities constitute an important part of the setting within which the great Canadian panhandling debate is currently being played out.

Thus, when issues of social policy are being discussed and debated by the community, it is of the highest importance that the privileged classes are not denied opportunities to hear and to take seriously the voice of the poorest and most oppressed members of society.

All thumbs

Housing and health in Canada

The French have a saying that their heart is on the left while their wallet is on the right (avoir le coeur à gauche et le portefeuille à droite). The Germans remind us that the left hand is the one with the thumb on the right (Links ist, wo der Daumen rechts ist). In Canada, it seems, we're all thumbs.

Thousands of people in this country are homeless on any given night. In 1998, the Toronto Disaster Relief Committee (TDRC), co-founded by Toronto "street nurse" Cathy Crowe, declared homelessness a national disaster. Over the last decade, spanning both Liberal and Conservative governments, the situation has become worse. The health implications of homelessness are obvious to everyone except those who pamper their compassion and need high stimulants to rouse it. An article by Dr. Stephen W. Hwang (St. Michael's Hospital, Toronto), which appeared in the CMAJ nearly seven years ago, warned of the problems caused by homelessness:

Homelessness affects a significant number of Canadians of all ages and is associated with a high burden of illness, yet the health care system may not adequately meet the needs of homeless people. More research is needed to identify better ways to deliver care to this population. Health interventions alone, however, are unlikely to overcome the adverse effects of homelessness and related social ills. The search for long-term solutions to the problem of homelessness itself must remain a key priority.

A report released last August by the Canadian Institute for Health Information (CIHI) sheds some new light on the complex relationship between mental health and homelessness in this country. People who are homeless are more likely to suffer from a mental illness or compromised mental health than the general population. On the other side of the coin, people with severe mental illness generally experience limited housing, employment and income options.

Improving the health of Canadians: mental health and homelessness provides an overview of the latest research, surveys and policy initiatives related to mental health and homelessness and, for the first time, presents data on hospital use by homeless Canadians. According to one startling statistic contained in this document, 52% of the visits to Canadian hospitals by homeless people are due to mental disorders, compared to only 5% among the general population.

People who are homeless tend to report higher stress, lower self-worth, less social support and different coping strategies — factors that are associated with depressive symptoms, substance abuse, suicidal behaviours and poor self-rated health. And the homeless mentally ill inevitably end up in hospital emergency departments.

The troubling relationship between mental illness and homelessness has been known for decades, and ample evidence was brought forth in the CMAJ article quoted above:

The prevalence of mental illness and substance abuse among homeless people is difficult to determine precisely, but consistent patterns have emerged from methodologically rigorous studies conducted in the United States and Canada. Contrary to popular misconceptions, only a small proportion of the homeless population has schizophrenia. The lifetime prevalence of schizophrenia is only 6% among Toronto's homeless population, and US studies have found prevalence rates of 10%–13%. Affective disorders are much more common, with lifetime prevalence rates in the range of 20%–40%.

The research called for in past years has been done. While there is always something else that can be learned through research, the general picture is quite clear. This country has a problem that is not going away. The studies have gone on long enough. To avoid "paralysis through analysis" society must act.

Bill Wilkerson, co-founder of the Global Business and Economic Roundtable on Addiction and Mental Health, expressed his impatience: "We have known for 25 years what this report is telling us yet again," he said. "So it's time for action, not time for more study." Wilkerson was involved in a task force that scrambled to find housing for mentally ill people who were deinstitutionalized in Ontario in the early 1980s. "The only difference, I think, is the problem then was new. Now it's old," he said. (Canadian Press report, 30 Aug 2007)

"The most obvious solution to homelessness is housing," says Tim Aubry of the Centre for Research on Educational and Community Services at the University of Ottawa (quoted in The Globe and Mail, 31 Aug 2007). There are two lengthy reports that confirm this common-sense remark. Housing is good social policy was published in 2004 by the Canadian Policy Research Networks. The authors elucidate further the link between homelessness and physical and mental health deficits. They argue that providing adequate housing is vitally important. "Spending money on housing does not take money out of health care – it reduces the cost of health care." Shelter: homelessness in a growth economy was released in July 2007 by the Calgary-based Sheldon Chumir Foundation for Ethics in Leadership. It claims that Canada's homeless population may be as high as 300,000. These staggering numbers are directly linked to increasing poverty levels. The government's response to homelessness has been "conflicted, sometimes bordering on outright neglect," and "has exacerbated efforts to reduce poverty in Canada." The report concludes:

If neglected, housing insecurity will continue to spread across Canada, fueling the relatively new phenomena of suburban homelessness, accelerating urban decay, and, in the face of record-setting housing prices, ensure the general economic erosion of millions of Canadians.

The Canadian government's new Homelessness Partnering Strategy began on April 1, 2007. It claims to be providing $269.6 million over two years to help communities across Canada combat homelessness. However, there is no housing in it, and it amounts to little more than a homelessness disaster relief program.

What of the response to the growing mental health crisis and its relationship to homelessness? On August 31 Prime Minister Stephen Harper announced the final selection of the Board of Directors for the newly created Mental Health Commission of Canada, which will receive funding of $55 million over five years. The Commission's goal is to help bring into being an integrated mental health system that places people living with mental illness at its centre. Sounds like more expense accounts and meetings, leading to more research.

Canadians are still waiting for an initiative that will include successful social housing as an integrated component of a broader social and economic policy to improve the health and welfare of the disadvantaged. Cathy Crowe of the Toronto Disaster Relief Committee wrote a powerful op ed piece last July about the Canadian housing crisis. She says: "Homelessness is our Katrina, but it wasn't caused by the weather." A public health nurse, Crowe is the author of Dying for a home: homeless activists speak out.


Meanwhile, our government does not see the irony in announcing last July that an American anti-virus software company is "donating security technology and expertise to 450 homeless shelters, which will help to ensure the protection of sensitive information on clients and operations." There are many excellent anti-virus and firewall programs available for free on the Internet. Here is the Canadian government crowing about supporting the work of shelters for the homeless, when all it is really doing is giving free feel-good publicity to a foreign corporation.

How does all this concern me as a librarian? The Diary of a Subversive Librarian highlights this quote from America Gone Wrong: A Slashed Safety Net Turns Libraries into Homeless Shelters:

In a democratic culture, even disturbing information is useful feedback. When the mentally ill whom we have thrown onto the streets haunt our public places, their presence tells us something important about the state of our union, our national character, our priorities, and our capacity to care for one another. That information is no less important than the information we provide through databases and books. The presence of the impoverished mentally ill among us is not an eloquent expression of civil discourse, like a lecture in the library’s auditorium, but it speaks volumes nonetheless.

Only a humanity to whom death has become as indifferent as its members, a humanity that has itself died, can inflict death administratively on innumerable people.

Theodor Adorno, Minima Moralia

Barriers to Best Practice

Just when I least expected it, I received a real stumper of a literature search request. A client from Public Health was looking for any recent research – actually anything at all – on the effectiveness of plastic wrap (a.k.a. shrink wrap, Saran Wrap) as a safe barrier for oral sex. That should be easy, I thought, an interesting little side trip through the web, visiting some well-known safer sex sites and gleaning any references on offer. Not one to shrink from a challenge, I plunged right in.

Little did I know what I was getting into: there is more to wrap than sandwiches. The web contains multitudes of safer sex sites, most of them offering opinions on the use of plastic wrap. Where advice is given it covers the range from squeamish acceptance to lukewarm approval. But not one of these sites offers evidence in support of its opinion. Not even the CDC.

Unrolling the Secret of Polyethylene

Disappointed, I initiated a formal literature search. I began, as usual, with PubMed. It offered very little, although I did discover the unfamiliar MeSH headings Rubber Dams, Cellophane, Permeability, Polyethylenes, and Polyvinyl Chloride. Most of what literature I could find on safe sex barriers is about latex. Some articles on non-latex barriers, which looked promising initially, were actually about the shelf life or resistance to tearing of the material, or its permeability to semen, not about its ability to withstand microbial penetration.

Google Scholar, as usual, was a mess, with everything from a goofy patent for a safe-sex mask to a study of oral gratification in Melville’s Typee. As I anticipated, just-plain-Google was able to produce, amidst the unavoidable prodigality of its porn links, reams of consumer health literature. Much of this had not been updated in years. Here is a representative sample:

• An undated web page from the www.iwannaknow.org site of the American Social Health Association mentions Saran Wrap in its discussion of dams.

• HIVInsite calls it "probably the most versatile barrier." No mention of the least versatile.

• Gay Men’s Health Crisis says that it stops HIV and advises: "Be careful not to turn the dam or plastic wrap inside-out while you use it."

• Some sites, such as the lgbthealthchannel, warn that ordinary plastic wrap can be used as a dental dam "as long as it is not the microwavable kind, which is porous." The question of which is which is left to the reader.

• A cautious admonition comes from the Centers for Disease Control and Prevention (HIV/AIDS among women who have sex with women, dated June 2006): "Plastic wrap may offer some protection from contact with body fluids during oral sex and thus may reduce the possibility of HIV transmission."

• Even more cautious is the 2006 Oral Sex pamphlet from the Canadian Public Health Association, which does not even mention plastic wrap, only dams. Did they check the literature and decide that the evidence simply wasn’t there?

• The men’s safe sex tips from Toronto’s Hassle Free Clinic also omit any mention of plastic wrap.

In none of the resources I found is there any evidence cited for the efficacy of plastic wrap in preventing the transmission of STIs. This is not purely an academic exercise. In a poster prepared by the Project START Study Group, Sexual behavior and substance use during incarceration (2004), we learn that 12% of incarcerated men in the United States are using Saran wrap and other plastic substances as a means of protection during consensual sex. Among lesbians and bisexual women, 2% report using plastic wrap for oral sex, according to a 2000 article in the Journal of the Gay and Lesbian Medical Association. What are heterosexuals doing? What about HIV-discordant couples?

I’m still looking for the evidence, and I have extended my search to other resources like Scopus and Web of Science. I have come across considerable research (and controversy) about the effectiveness of latex condoms, dams, and gloves, and polyurethane barriers such as female condoms. But the case for wrap is not transparent.

Safer Saran Wrap

The always surprising Wikipedia has articles on plastic wrap in general, and Saran in particular. It turns out this stuff is not the homogeneous thing I thought it was. Plastic wrap, known as cling film in Britain and cling wrap in Australia, was discovered by accident in 1953. In Canada, Saran Wrap is the genericized trademark. The original Saran Wrap was made of polyvinylidene chloride (PVdC). In 2004 the formulation was changed to low density polyethylene (LDPE). The manufacturer claimed that this change was a result of an initiative to look for more sustainable and environmentally acceptable plastic. The film in Saran Premium Wrap does not contain chlorine, which is a good thing. However, we are told that LDPE does not possess the same barrier qualities to oxygen, aroma, and flavour molecules as vinylidene chloride copolymers, making the new formulation a lower quality plastic wrap, less useful in protecting from spoilage or flavour loss. How would it deal with HIV or treponema pallidum pallidum?

I went to the official Saran website, http://saranbrands.com/. The manufacturer, SC Johnson & Son, calls itself a "family company." They have an online survey: "How do you use Saran products?" Wouldn’t they like to know. In the FAQ I discovered that Saran Wrap is microwaveable. I guess that would disqualify it from use in oral sex according to some so-called authorities. Beyond this, the website provides no assistance for the would-be barrier user. But believe me, the next time I’m putting away leftovers I won’t look at my roll of plastic wrap the same way ever again.

Plastic Wrap as Sex Accessory

To wrap up this discussion, there appears to be little scientific evidence for the safety of products like Saran or other plastic wraps when employed as barriers for oral sex. This is somewhat disturbing, given the near universal recommendation of plastic wrap – by officials of the state as well as community activists – for safer sex in the absence of preferred latex barriers like condoms or dental dams. In short, their reasoning is full of holes. Is this negligence or an excessively tolerant clinging to street-smart tradition? Could we also be dealing here with a coy, possibly sex-phobic reluctance to investigate the issue? Are we tempted to resort to lame humour in order to hide our embarrassment? Klingon safe sex: no bladed weapons!

There are other reasons for the lack of reliable information on plastic wrap. For one thing, this kind of research is unlikely to further any scientist’s career. Don’t expect generous government grants or a chirrupy announcement from the Bill and Melinda Gates Foundation. Another possibility, I suppose, is that either through innocence or denial this research topic has simply not yet occurred to anyone. Or is that stretching credibility till it snaps?

All I can say is that the next curious patron who comes to the library with this question will not find a barrier in me.

Selected, unsatisfactory references:

1. What's in store for non-latex barrier methods. Contracept Technol Update. 1998 Mar;19(3):40-1.

2. Carey RF, Lytle CD, Cyr WH. Implications of laboratory tests of condom integrity. Sex Transm Dis. 1999 Apr;26(4):216-20.

3. Cornish K, Lytle CD. Viral impermeability of hypoallergenic, low protein, guayule latex films. J Biomed Mater Res. 1999 Dec 5;47(3):434-7.

4. Drew WL, Blair M, Miner RC, Conant M. Evaluation of the virus permeability of a new condom form women. Sex Transm. Dis. 1990 17(2):110-2.

5. Free MJ, Srisamang V, Vail J, Mercer D, Kotz R, Marlowe DE. Latex rubber condoms: Predicting and extending shelf life. Contraception. 1996 Apr;53(4):221-9.

6. Frezieres RG, Walsh TL, Nelson AL, Clark VA, Coulson AH. Evaluation of the efficacy of a polyurethane condom: Results from a randomized, controlled clinical trial. Fam Plann Perspect. 1999;31(2):81-7.

7. Gallieni M. Transparent film dressings for intravascular catheter exit-site. J Vasc Access. 2004;5(2):69-75.

8. Imran D, Sassoon E, Lewis D. Protection of dressings and wounds by cling film [22]. Plast Reconstr Surg. 2004;113(3):1093-4.

9. Klein RC, Party E, Gershey EL. Virus penetration of examination gloves. BioTechniques. 1990 Aug;9(2):196-9.

10. Korniewicz DM. Effectiveness of glove barriers used in clinical settings. Medsurg Nurs. 1992 Sep;1(1):29-32.

11. Korniewicz DM, El-Masri M, Broyles JM, Martin CD, O'connell KP. Performance of latex and nonlatex medical examination gloves during simulated use. Am J Infect Control. 2002 Apr;30(2):133-8.

12. Korniewicz DM, Kirwin M, Cresci K, Sing T, Choo TE, Wool M, et al. Barrier protection with examination gloves: Double versus single. Am J Infect Control. 1994 Feb;22(1):12-5.

13. Lytle CD, Routson LB, Cyr WH. A simple method to test condoms for penetration by viruses. Appl Environ Microbiol. 1992 Sep;58(9):3180-2.

14. Lytle CD, Routson LB, Seaborn GB, Dixon LG, Bushar HF, Cyr WH. An in vitro evaluation of condoms as barriers to a small virus. Sex Transm Dis. 1997 Mar;24(3):161-4.

15. Macaluso M, Blackwell R, Jamieson DJ, Kulczycki A, Chen MP, Akers R, et al. Efficacy of the male latex condom and of the female polyurethane condom as barriers to semen during intercourse: A randomized clinical trial. Am J Epidemiol. 2007 Jul 1;166(1):88-96.

16. O'Grady NP, Alexander M, Dellinger EP, Gerberding JL, Heard SO, Maki DG, et al. Guidelines for the prevention of intravascular catheter-related infections. centers for disease control and prevention. MMWR Recomm Rep. 2002;51(RR-10):1-29.

17. Rego A, Roley L. In-use barrier integrity of gloves: Latex and nitrile superior to vinyl. Am J Infect Control. 1999 Oct;27(5):405-10.

18. Wiwanitkit V. Bloodborne viral pathogens and the feasibility of passing thorough the gloves: An appraisal and implication on infection control. Am J Infect Control. 2006 Aug;34(6):400.

19. Yip E. Consideration of barrier protection and latex protein allergy in the evaluation of medical gloves. J Infus Nurs. 2004 Jul-Aug;27(4):227-31.