MINERAL OIL LUBRICANTS CAUSE RAPID DETERIORATION OF LATEX CONDOMS Bruce Voeller*, Anne H. CoulSOn? Gerald S. Bernstein', Robert M. Nakamura3 1Mariposa Foundation, 3123 Schweitzer, Topanga CA 90290 'UCLA School
of Public Health
3Dept. of Obstetrics and Gynecology, USC School of Medicine, Los Angeles
ABSTRACT As little as sixty seconds' exposure of commercial latex condoms to mineral oil, a common component of hand lotions and other lubricants used during sexual intercourse, caused approximately 90% decrease in the strength of the condoms, as measured by their burst volumes in the standard IS0 Burst (International Standards Organization) Air Burst Test. pressures were also reduced, although less dramatically. Lubricants such as Vaseline Intensive [email protected]
Johnson's Baby Oil? each containing mineral oil, also affected condom integrity. Five min. exposure of condoms to glycerol, a frequent component of hand lotions and 'personal lubricants', did not significantly Aqueous nonoxynol-9 spermicide affect burst volume or pressure. did not affect either burst index. The implications of these results for contraception protection from sexually transmitted diseases, including are discussed.
INTRODUCTION Condom users have long been admonished that oil-based lubricants weaken latex condoms! However, a literature search, as well as extensive discussion with senior researchers at British and American condom manufacturers, at the U.S. Food and Drug Administration (FDA), and at the Consumers Union, indicates that little experimental data exist to substantiate this warning. Industrial experience -- that prolonqed exposure of latex goods to petroleum products causes deterioration -- justifies concern about oils and condoms. But it is unclear how relevant Submitted for publication October Accepted for publication November
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7, 1988 1, 1988
such information is to condom use. On the one hand, condoms are thin latex films with large surface-to-volume ratios which offer ease of attack by gases, fluid agents, and deleterious wavelengths such as ultra violet. On the other hand, the duration of exposure of condoms to lubricants during sexual activity usually is rather brief compared with most industrial exposures of latex; industrial exposure is commonly measured in While sexual intercourse may continue for days, weeks or months. 15 minutes or longer, Kinsey et al. document that on averaae, intercourse lasts less than 2 min.' The question thus becomes, do lubricants used during intercourse interact with latex quickly enough to cause condoms to break or leak during the averaqe duration of sexual intercourse -- or even during marathon sex? Mineral oil causes visible blisters to appear in latex condoms within three to four minutes? and Voeller et al.4 reported that 15 min. exposure of condoms to mineral oil allowed leakage of the AIDS virus, HIV-l [12 of 23 condoms]. Fifteen min. exposure to diverse oils recently has been reported to induce striking loss of the tensile strength in condoms.5 In the present study we treated latex condoms with mineral oil or other lubricants for periods ranging from 60 sec. to one We measured the change in condom integrity by monitoring hour. decreases in burst volumes and pressures in the standard IS0 (International Standards Organization) Air Burst Test. While this is a quality control test of condom strength, required in many countries as a manufacturing standard, it may also predict the performance of condoms during actual use.617 METHODS Generic, non-lubricated condoms were supplied by Schmid Laboratories, Inc. These condoms were loose packed [not in foil Two manufacturing lots were employed, wraps) and non-rolled. differing in age by approximately 9 months. Customary IS0 Air Burst Tests were conducted utilizing purified nitrogen gas, rather than In the Air Burst Test, the open rim air, as the inflating gas. of a condom is fitted over the opening atop the Air Burst Instrument, and the condom is inflated at a standard rate of 24.5 Burst pressure is measured L per minute until the condom bursts. in kilo-Pascals (kPa) and burst volume in liters. In the present tests, the outer surfaces of eleven replicate condoms were individually wetted by immersion in a beaker of test fluid to one half their length (measured from the closed tip of the condom). The condoms were laid out upon filter paper for designated time intervals. Near the end of the interval, they were patted with filter paper to remove excess fluid, and tested on the Air Burst Designated time Instrument for burst time, volume and pressure. periods were measured from the start of immersion of the exposed
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portion of the condom, until the beginning of the inflation of the treated condom on the Air Burst Instrument. All lubricant operations were conducted at room temperature. All tests were run with and compared controls.
Lubricant fluids tested were: . triple glass distilled water . mineral oil, light (E.H. Sargent & Co, Lot #F&?. Viscosity 80-90 Saybolt) I Squibb Mineral Oil@ . Johnson's Baby Oil@ . Vaseline Intensive [email protected]
. glycerol [glycerin] (Mallinckrodt, analytical grade) . an aqueous, generic spermicidal gel containing: 1.5% hydroxyethylcelluose (Union Carbide) 30% glycerol (Emery Industries) 1% nonoxynol-9 (GAF Corporation) The effect of water was tested both to see if it had an effect per se on condom strength and to evaluate whether the physical manipulations involved in lubricating the test condom affected test results. RESULTS The results are presented in Table I and Fig. 1. Table I includes data from two lots of test condoms, one approximately 10 months old (from date of manufacture), and the other approximately one month old. Means and standard deviations (S.D.) for burst pressure and burst volume for each lot and treatment are presented. The lower limit of the IS0 value [that limit below which a condom is counted as a failure) is given in the same units for comparison. Control condoms from the two lots showed different volume values as well as different pressure values, which probably were due to the difference in age of the condoms. For example, the older condoms (Lot 1) had a mean burst volume only 58.6% that for Lot 2. Thus, for purposes of comparing the effects of lubricants between the two series of experiments, the data are presented in Fig. 1 as percentages of the relevant control values. Preliminary mineral oil studies revealed that no significant differences existed among results from 60 min., 15 min., 5 min. and 1 min. exposure times. Thus the data depicted in Table I and Fig. 1 represent 60 sec. exposures, with the exception of Vaseline Intensive [email protected]
glycerol, each with exposure times of 5 min.
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CONDOI AIR BURST TEST VOLUMES AND PRESSURES WITH CONDOMS (10 mo. and 1 mo. old) TREATED SECONDS OR 5 I4INUTES (+) - MEAN f S.D. pressure JkPa)
Condom Lot 1 (10 mos.
OF TWO LOTS OF LUBRICANTS FOR
Control + Glycerol + Vaseline Intensive Care@ Squibb Mineral Oil@ Sargent Mineral Oil"
1.60 1.40 1.22 0.85 0.85
f0.12 f0.23 iO.10 f0.03 f0.04
NS <.05 <.OOOl <.OOOl
28.9 24.4 22.5 4.2 2.8
f2.4 zt5.9 NS f3.3 <.OOl f1.4 <.OOOl f0.6 <.OOOl
1.98 1.93 2.01 0.80 0.76
fO.10 NS kO.08 NS *0.05 zlzO.05 <.OOOl kO.02 <.OOOl
49.3 46.2 50.6 15.1 7.0
f3.6 f2.3 f2.5 f2.1 f2.0
Condom Lot 2 (1 mos. old1 Control Distilled Water Spermicide Squibb Mineral Oil@ Johnson's Baby Oil@ IS0 MINIMUM
NS NS <.OOOl <.OOOl
Both types of mineral oil, and Johnson's Baby Oil@, significantly reduced the burst pressure and burst volume of the condoms tested. While the means (volume and pressure) for glycerol were lower than those for the controls, they were Vaseline Intensive Care@ not siqnificantly different. Lotion significantly decreased both the burst volume and the burst pressure. Burst pressures for the distilled water and spermicide The results treated condoms were not different from controls. with distilled water also demonstrate that the mechanics of lubricant application employed in these studies is not a significant source of the damage to the tested condoms, compared with untreated controls.
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Air Burst Test Results for Lubricants %Control Control
L 0 T
Miner 81 Oil
M~rwrel Oil@ UJlfll 0%
1 0 +
I UlIN Volume
Burst volumes and pressures of year-old condoms treated with lubricants for 60 sec.
DISCUSSION The results presented demonstrate that mineral oil acts very The rapidly to damage the latex condoms used in this study. rapidity of this dramatic effect, which occurs within 60 sec., is an order of magnitude faster than is suggested from other recent studies in which condoms were exposed to lubricants for 15 min. or longer.4p5 While yet briefer exposure periods will be tested, times less than 30 sec. are difficult to measure accurately
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because of the several physical manipulations of the condoms required in studies such as those reported here. Moreover, a these short time periods are distinct from the longer term ones typically characterizing deterioration of nonfilm latex products. The rapid effects seen here upon condoms fall in the same time range as the duration of sexual intercourse, where condoms are commonly used with lubricants. As noted
and his colleagues
"For perhaps three-quarters of all males, orgasm is reached within two minutes after the initiation of the sexual relation, and for a not inconsiderable number of males the climax may be reached within less than a minute or even within ten or twenty seconds after coital entrance." * Nearer the upper end of the range for the duration of sex, intercourse lasting over a quarter of an hour (with constant penile penetration) has been observed repeatedly.8 The use of a single condom during even more prolonged sexual activity doubtless occurs. With respect to such periods -- seconds to an hour -- the Air Burst Test results presented here underscore concern that combining the use of condoms with the use of products containing mineral oil is risky. This concern should not be limited to 'marathon' sex, but includes even the briefest sexual intercourse. Interviews with 25 men who consistently broke latex condoms during post-penetration sexual intercourse indicated that 23 of the 25 men regularly used either Johnson's Baby Oil, Vaseline Intensive Care or Nivea hand lotions to facilitate sexual intercourse.8 Mineral oil was found to be a common component of each of the lubricants used, as well as of many others employed during sexual intercourse. Moreover, a survey of a geographically diverse sampling of 1275 American males indicated that Vaseline Intensive Care was the most frequently used sexual lubric;nt (61% who ever used), and the highest ranked lubricant Baby oil or other oil-based lubricants also were the (19%). first choice of over half of 145 British males (82 men out of 145, or 57%) .lO,ll Johnson's Baby Oil is nearly pure mineral oil, Vaseline The results in Fig. Intensive Care lotion contains mineral oil. 1 demonstrate that Johnson's Baby Oil especially quickly affects condom strength and that Vaseline Intensive Care, while less rapidly destructive, has an effect within five minutes' exposure. When persistent
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evident that the probable source of their breakage was that t&ey mista&enly thought [email protected]
as Vaseline Intensive Care, Nivea, and Johnson's Baby Oil, were water-based, because they washed off fairlv readilv with water, compared with Vaseline (petrolatum) or Crisco (hydrogenated vegetable oil).* Only the latter were perceived as proscribed oil-based lubricants. The one generic spermicidal gel which was tested caused no significant reduction in the strength of the test condoms, These results, and those from distilled water controls, add support to the belief that water-based lubricants, including spermicidal This observation is of gels, are safe for use with condoms. importance because of the increasing emphasis placed upon this surfactant's use in AIDS prevention recommendations, such as those of the Surgeon General.12 While further kinetic studies of the effects of a wider range of lipid and non-lipid chemicals, and of different brands of condoms, are needed, the present results demonstrate that some Use oils cause extremely rapid and profound damage to condoms. of such oils poses clear danger to those employing condoms for contraception or the prevention of sexually transmitted diseases, including AIDS. REFERENCES
Consumer Reports. Condoms: a report based on laboratory tests and on detailed questionnaires filled out by nearly 1900 readers. PP. 583-588. (1979) Kinsey, A C, Pomeroy, W B, and Martin, C E. Sexual Behavior in the Human Male. W.B. Saunders Company, Philadelphia, 1948 Voeller, B. In: Minutes of the Roundtable Meeting on New Condom Design, National Institute of Child Health and Human Development; National Institutes of Health. (April P. 7 20, 1988) Voeller B, Hicks D, Coulson AH, Bernstein GS, Nakamura Browdy B, Detels R: Testing HIV leakage through condoms [Abstr. #6508, p. 273].IV International Conference on AIDS, Stockholm (1988) White, N, Taylor, K, Lyszkowski, Morris, C. Dangers of lubricants Nature 335:19 (1988)
A, Tullett, J, used with condoms.
Free, M J, Skiens, E W, Morrow, M M. Relationship between condom strength and failure during use. Contraception 22:31-37 (1980)
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Free, M JI Hutchings, J, Firman, L, Natakusumah, R. An assessment of burst strength distribution data for monitoring quality of condom stocks in developing countries. Contraception 33: 285-299 (1986).
Walker and Struman Research, Inc. Advocate, Los Angeles, CA, 1981
Sonnex,C, Howard L C, Samarasinghe PL. Sexual behaviour [Abstr. and condom usage by homosexual men in London #WP.173]. III International Conference on AIDS. Washington, D.C. (1987)
Koop, C.E. Physician leadership in preventing AIDS [editorial].J.A.M.A. 258:2111 (1987)
unpublished. The Advocate Survey.
Personal Communication to B. Voeller.
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