Here is a well written position paper by Karen Messana that we rely on for guidance regarding issues surrounding the use of contact lenses in our Research Laboratories. Al Muehlhausen Health, Safety, and Environmental Officer Corporate Headquarters and R&D CIBA Vision Corporation Years of lens use and research studies have settled the issue: Wearing contacts in a chemical environment or other environments doesn't increase the risk of injury. by Karen Messana Safety professionals should no longer take the position of prohibiting the wearing of contact lenses in the workplace, and the requirements to wear PPE for "eye hazardous" situations should be no different for wearers than non-wearers. Why can this be said? Because after 40 years of contact lens use, there is no well-documented information that wearing contacts increases the risk of injury over that of non-wearers and wearers of spectacles, whether we are talking about foreign bodies, or chemicals, or other eye hazard sources. Studies have looked at eye hazards such as flying metal/dust particles, chemicals, and radiant energy such as UV and IR. (1, 2, 3) Specific chemicals tested include acetone, ammonia, acetic acid, creosol, butylamine, toluene, xylene, diethyl ether, trichloroethylene, sodium hydroxide, sulfuric acid, hydrochloric acid, and tear gases.(4, 5, 6) In each instance, none documented a greater risk of injury to the contact lens wearer over the non-wearer--and in most, a protective effect was noted. In addition, there is a paucity of reported or anecdotal evidence of injuries resulting from contact lens use in the workplace.(7, 8) A review of 7,000 contact lens-related abstracts on the PubMed Web site spanning more than 30 years resulted in only a handful of studies or reviews regarding contact lenses in the workplace. None resulted in conclusions that wearing contacts in a chemical environment or other environments increased risk of injury. Studies show that for each instance of eye injury demonstrated to be more severe due to wearing contact lenses, there are about 30 instances where similar exposure circumstances prevented or reduced injuries, or at least did not increase the severity of the injury, when the person was wearing contact lenses.(9, 10, 11) Put another way: Every time we prohibit someone from wearing contact lenses in an eye hazardous environment, we increase our chances of that person experiencing an eye injury greater than would have occurred if an "accident" happens. Logic dictates that wearing contacts should be encouraged in such environments, not discouraged. The Seat Belt Analogy We all know it wouldn't be hard to find a study or two that indicated that some people suffer more injury from wearing a seat belt than from not wearing a seat belt when a collision occurs. However, the vast majority of the time, the seat belt user is either protected from any injury, the severity of the injury is reduced, or there is no difference in injury outcome when compared to a non-seat belt wearer. Knowing this, we choose to wear the seat belt because of its overall beneficial effect. Replace the words "seat belt" in this paragraph with "contact lenses," and the same substantiated statement of benefit can be made. So where have our concerns about contact lenses in the workplace come from? When contact lenses first became an issue of concern in the workplace, there were no guidelines or data to consider in assessing risk associated with their use. Based on worst case scenarios, perceived risks, and problems encountered by new wearers of contact lenses, conservative positions were taken by authoritative bodies that prohibited contacts lens use in industrial environments, even when additional eye protection was worn. At the time, the primary fears and perceived risks included statements such as: ? Foreign bodies, normally washed away with tears, could become trapped under the lens and thereby abrade the cornea (the cornea is the part of the eye we see through, and contacts fit directly over the cornea, hence the concern). ? Chemicals could absorb through the lens, resulting in subsequent injury to the cornea. ? Chemicals entering the eye could cause eyelid spasms that would prevent removal of the lens for flushing. In addition, two widely misreported incidents fueled concerns about the hazards of contact lenses and lent credibility to unsubstantiated beliefs. The first was the 1967 arc flash that supposedly fused the worker's contact lenses to his eyes, and when the lenses were removed, the cornea peeled off and he was blinded.(12) In reality, the worker wore his lenses too long and suffered a corneal ulceration, which healed completely in a couple of days. He had been exposed to an electrical arc the same day without incident, hence the source of the rumor. The second incident involved a widely-read industrial ophthalmologist who, while proposing a restrictive contact lens use policy, used a chemical eye injury incident to support his position.(13) The incident involved a 50 percent caustic splash to an engineer's face while wearing contact lenses with goggles; although the engineer suffered eye injury, there was no documentation of how the contacts contributed to the injury, if at all, or what type of goggles were involved. Foreign Bodies, Chemicals With regard to the concern of foreign body being under a lens, studies and anecdotal situations have proven these beliefs to be unsubstantiated.(1, 2) The theory of what actually happens is that the normal adhesion force of the lens to the eye surface prevents a foreign body from entering the space under it, and particles are easily removed by normal tearing, blinking, and cleaning. Although studies have shown that some chemicals can be absorbed into certain soft lenses, the studies have not demonstrated that the chemicals reach the other side and injure the cornea. Typically, the contact lens initially acts as a sponge/vacuum, keeping the chemical in its core and away from its surfaces.(11, 14) In addition, studies imply that tears attract the absorbed chemical to come back out and away from the lens. Furthermore, it is unlikely chemicals of concern (corrosives) are absorbing into the lens fast enough to become trapped under the lens without plenty of notice ahead of time to the wearer. Imagine being splashed in the eye with a corrosive or vapors slowly accumulating their concentration in the lens. The eye pain and irritation would necessitate prompt flushing action, with subsequent removal of the lens. In addition, when the eye is chemically attacked, studies postulate that the eye spasms and literally sucks the lens against the corneal surface, preventing the chemical from entering that space for some period of time.(15) Meanwhile, the person would be flushing the eye with water, greatly diluting any residual chemical. The contact lenses would have protected the cornea from the immediate, direct contact of the highest concentration of the substance. What Do the Experts Say Today? The American Chemical Society's Committee on Chemical Safety: "In many workplaces, where hazardous chemicals are used or handled, the wearing of contact lenses is prohibited or discouraged. A good number of these prohibitions are traceable to earlier statements based on rumors and perceived risks. A careful study of the literature has refuted these risks. Recent studies and experience have suggested that, in fact, contact lenses do not increase risks but can actually minimize or prevent injury in many situations. It is the consensus of the committee that contact lenses can be worn in most work environments provided the same approved eye protection is worn as required of others in the area. It should be stressed that contact lenses, by themselves, do not provide adequate protection in any environment in which the chance of an accidental splash of a chemical can reasonably be anticipated."16 The American Optometric Association: "An evaluation of the published material, including laboratory and animal studies, and well documented case reports, indicates that contact lenses may be worn safely under a variety of environmental situations including those which, from a superficial evaluation, might appear hazardous. Indeed, some types of contact lenses may give added protection to spectacle lens and non-spectacle lens wearers in instance of certain fume exposure, chemical splash, dust, flying particles, and optical radiation. The evidence also refutes the claims that contact lenses negate the protection provided by safety equipment or make the cornea more susceptible to damage by optical radiation. . . . Regulations limiting the wearing of contact lenses in any given circumstances must be scientifically defensible and effectively enforceable. They should not be based on perceived hazards, random experience, isolated unverified case histories, or unsubstantiated personal opinions."(17) OSHA's preamble for the Final Rule on PPE in 1994 states: "OSHA believes that contact lenses do not pose additional hazards to the wearer and additional regulation is unnecessary." In summary, it is reasonable to allow the use of contact lenses in any area that the unaided eye is permitted. It is not necessary to require removal of contact lenses prior to entering eye hazardous environments. Instead, require the use of PPE and if PPE is to be worn, then, base it on the assessment that all persons need to wear the PPE, not just contact lens wearers. Overall, safety professionals can ensure that eye protection policies are in writing, a PPE hazard assessment is conducted, proper eye protection is designated, contact lens users are identified, emergency and first aid procedures are addressed, and contact lens wearers are educated and trained. In addition, these wearers should be encouraged to have a spare set of corrective lenses available on the job. References 1. Nilsson, S.E.G., P. Lovsund and P.A. Oberg: Contact Lenses and Mechanical Trauma to the Eye. Acta Ophthalmol . 59:402-408 (1981). 2. Nilsson, S.E.G., H. Lindh and L. Andersson: Contact Lens Wear in an Environment Contaminated with Metal Particles. Acta Ophthalmol . 61:882-888 (1983). 3. Owen C.G, T.H. Margrain T.H., E.G. Woodward: Use of Contact Lenses by Firefighters: Part 2. Clinical Evaluation. Ophthalmic Physiol Opt . May; 17 (3):205-15 (1997). 4. LaMotte, J., G. Smith, A. Chang Smith: "Absorption of Ammonia by High Water Content Hydrogel Lenses: An Inexpensive Method of Analysis"; Optometr y and Vision Science , 72:605-607 (1995). 5. Aalphen, C.C. Kok-van, W. van der Lindern, R. Visser and A.H. Bol: Protection of the Police Against Tear Gas with Soft Lenses. Mil Med . 150(8 ):451-453 (1985). 6. Hejkal T.W., R.E. Records, C. Kubitschek, C. Humphrey: Diffusion of Volatile Organics Through Contact Lenses. CLAO J . Jan 18(1):41-45 (1992). 7. Hirschfelder, D.: Contact Lenses in the Workplace: The Dilemma. Sight Sa v. Rev . 52(1):14-18 (1983). 8. Contact Lens Association of Ophthalmologists, Inc.: "Position Paper--Industrial Safety." New Orleans , LA , 1979. 9. Blais, B.R.: "The Use of Contact Lenses in an Industrial Environment" (unpublished manuscript). Bethesda , Maryland : Uniformed Services University of the Health Sciences, April 1985. 10. Wesley, N.K.: Chemical Injury and Contact Lenses. Contacto . 10(3):15-2 0 (1966). 11. Nilsson, S.E.G. and L. Andersson: The Use of Contact Lenses in Environments with Organic Solvents, Acids, or Alkalis. Acta Ophthalmol . 60 :599-608 (1982). 12. Contact Lens Association of Ophthalmologists, Inc.: Policy Statement on Arc Welding and Contact Lens Wear. Cont. Intraocular Lens Med. J . 9(4): 343 ( July 23, 1983 ). 13. Kuhn, H.S.: Contact Lenses-Threat to Vision? Nat. Saf. News . June:23 ( 1961). 14. Tredici, T. J. and W.J. Flynn: The Use of Contact Lenses by USAF Aviators. Avia., Space, Environ. Med . 58:438-443 (1987). 15. Guthrie, J.W. and G.F. Seitz: An Investigation of the Chemical Contact Lens Problem. J. Occup. Med . 17(3):163-166 (1975). 16. www.pubs.acs.org/cen/safety/19980601.html 17. www.aoanet.org/ia-cl-ind-environ.html Karen Messana ( kmessana**At_Symbol_Here**trinitymfg.com ), CSP, MS Industrial Hygiene, has 21 years of safety experience. She currently is the EHS Manager for a chemical manufacturer. Messana wrote her master's degree technical paper on the workplace use of contact lenses in 1989 and has continued to follow the issue. http://www.safetydirector.com/ http://www.safetydirector.com/ =A9 Copyright 2001 Stevens Publishing Corporation 5151 Beltline Road, 10th Floor, Dallas, Texas 75240 ACTSNYC**At_Symbol_Here**CS.COM Sent by: DCHAS-L Discussion List11/14/2004 02:59 PM Please respond to ACTSNYC To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU cc: (bcc: Al Muehlhausen/CV/Novartis) Subject: Re: [DCHAS-L] Goggles and Contact Lenses I agree with use of contact lenses as well. We mustn't oversimplify splash goggles either. There are vented, indirect vented, and unvented splash goggles. I need to recommend even different types of splash goggles for different purposes in my work. Eye protection is not Monona Rossol In a message dated 11/13/04 6:21:08 PM Eastern Standard Time, Labsafe**At_Symbol_Here**AOL.COM writes: > Phil is absolutely right. Chemical splash does need goggles. But the > problem is that many folks can't, don't, or won't distinguish between impact > and > chemical splash goggles. > > So, saying goggles in simply insufficient. One must say chemical splash > goggle for a chemical splash. And ANSI/ASSE could do us all a big favor by > asking > the manufacturer to put the selection chart letter after the Z-87.1 to > indicate the type of device. > > Concerning contact lenses, they do it for good reason. Six years ago, after > five years of study, the ACS Council Committee on Chemical Safety joined > other > major organizations (Prevent Blindness America, American Optometric > Association) and many companies (Dow, 3M, and DuPont) by agreeing that > contact lenses > are acceptable as long as all the other necessary eye protection is worn. > > So, I for one am not the least bit upset about contact lens use and very much > agree with the ACS position. ... Jim > >
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