Re: Hazards of formaldehyde
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|From:||Mequita Praet <mdpraet@Bellsouth.net>|
Thanks for taking to time to remind many of the effects of formaldehyde. I
suffered throughout the 70's and 80's with contact dermatitis from
formaldehyde. It took working for a Dermatopathologist whos interest was
occupational hazards to finally develop a treatment plan for me, together with
increased awareness of safety precautions, to control the problem. We become
lax as things become familiar. We forget hazards can sometimes be cumulative.
I would appreciate your page on xylene. Refresher courses in safety are always
to our advantage.
Again, thank you
> For several months there have been recurring threads concerning health and
> safety issues that have troubled us greatly at Anatech Ltd. The general
> theme has been to make light of toxicity claims, provide anecdotal comments
> about having survived many decades of working in labs, and giving the
> impression that current health and safety regulations are at best a pain
> and probably are the cunning products of misguided governmental agencies.
> There are approximately 1100 HistoNet subscribers (HistoLogic 31(2):37).
> Twenty or so seem to be regular contributors whose comments are given
> considerable credence by many of the readers. Regretably these regulars
> are creating an impression that can only harm the great strides we have
> made in the last 20 years toward making our labs safe. I cannot change the
> attitudes of many of these regular contributors, so I address the following
> comments to the rest of you, the 1080 or so reader, whose minds may still
> be open to reason and documented fact.
> The great hazard of formaldehyde is not its proven carcinogenicity. Anyone
> interested in formaldehyde's effects on humans should read the preamble to
> OSHA's Formaldehyde Standard (Federal Register 52(233):46168-46312;
> December 4, 1987). According to studies cited therein, formaldehyde has
> been directly implicated in causing tumors in the lungs, naso- and
> oro-pharynx and nasal passages of humans occupationally exposed to levels
> of formaldehyde not unlike conditions existing in histology laboratories a
> few decades ago. Repeated and prolonged exposure increases the risk.
> True, the risk is small, and with the improved ventilation in most US labs
> (at least), one could justify ignoring the issue altogether. I personally
> do not care to increase my risk, but the significance is truly minor.
> However, Formaldehyde presents a vastly greater risk to histotechnologists
> by being a potent sensitizer. Once sensitized, you will probably
> experience worsening symptoms for the rest of your life even if you leave
> the field. You cannot get away from formaldehyde. It off-gasses from most
> building products except untreated lumber. It has been widely used in the
> permanent press treatment for fabrics (although glyoxal is replacing it
> there as it is in histological fixatives). It comes out of carpeting
> drapes and upholstery. You will get more colds, suffer with them longer,
> may develop asthma, or experience worsening asthmatic attacks. OSHA
> reported in 1982 that 79% of the histotechnologists studied showed
> respiratory and dermatological symptoms consistent with
> formaldehyde-induced sensitization, a 2-fold increase over the control
> group. Exposure levels for those histotechs were 0.2-1.9 ppm, levels that
> were really rather moderate for the time (pre-1987).
> The Formaldehyde Standard was written in great part because of the
> unacceptable conditions in pathology labs. Industry had long since cleaned
> up its act. The standard's preamble specifically singles out pathology
> labs as being among the worst for workplace exposure.
> Perhaps many of you do not remember or were not in the field before 1980.
> A few techs were concerned about chemical exposures, but were mostly
> stymied by glib administrators and uncaring co-workers whose attitudes were
> strikingly like those being aired on the HistoNet today. NSH struggled
> many years to bring these concerns to light, organizing a Health & Safety
> Committee, sponsoring studies of formaldehyde and xylene exposure,
> providing workshops and lectures on all aspects of health and safety, and
> compiling lists of resource materials and personnel. The real leaders of
> this field have taken the subject very seriously. Please don't go back
> down that road in reverse; if you do, do it alone.
> I want to set the record straight. Formaldehyde can be worked with safely.
> No histotech should ever need a respirator. Simple, properly designed
> ventilation can easily keep vapor levels below the OSHA Action level of 0.5
> ppm averaged over 8 hours. If you stay below that level (and the STEL of 2
> ppm over 15 minutes), you avoid almost all of the standard's requirements
> and have a safe workplace at least for the inhalation of formaldehyde
> Skin contact with formaldehyde is another issue altogether. Latex surgical
> gloves offer NO protection (breakthrough time is seconds to a few minutes).
> Very thin nitrile gloves are probably marginally better, but breakthrough
> times are not available. This form of exposure is the cause of most
> modern-day sensitization reactions to formaldehyde. Butyl and nitrile
> gloves comparable in thickness to dishwashing gloves will protect you for
> most histological tasks involving formaldehyde (Schope et al., 1987,
> Guidelines for the selection of chemical protective clothing, ACGIH,
> Cincinnati, OH). Unfortunately, grossing is difficult with these
> protective devices.
> Making your own formalin makes economic sense only until you factor in
> labor, overhead and compliance costs. Couple that with QC issues and
> suddenly the commercial product from a reputable vendor is a lot more
> attractive. As Randy Kline has ably pointed out, having it made by a
> company conforming to Good Manufacturing Practices and controlled by the
> FDA goes a long way toward providing you with peace of mind that the
> solution actually does contain 3.7% formaldehyde. You can buy it
> cheaply,but you will get exactly what you paid for...as always.
> Finally, concerning the assaying of formalin, there are several methods
> available but few will provide the specific concentration with a given
> level of precision and accuracy. Of the latter, only one is feasible for
> general use (the others require glassware and calibrated standards that you
> don't want to mess with). Anatech Ltd. and B/R Instruments have an assay
> kit that unambiguously determines the concentration in increments of 2
> percentage units (e.g., 9.0-10.9%). The test takes a minute or two to
> perform once you become familiar with it.
> Sakura recently came out with test strips, like pH dip sticks, which are
> much easier to use but may be difficult to interpret (the color differences
> between 7.5% and 10% are debatable, the colors are transient, and the
> important color develops in the center of the stick's patch, not the edge,
> making comparison with the picture difficult).
> If safety issues are of concern or interest to you, obtain a copy of our
> Hazmat Maunal (Dapson & Dapson, 1995, Hazardous materials in the
> histopathogy laboratory, 3rd edition, available from Anatech Ltd.). The
> answer to virtually every health, safety and disposal question that has
> ever appeared on the HistoNet can be found within its 253 pages.
> I could continue with another tiresome page on xylene, but I'll spare you.
> ANATECH LTD.
> 1020 Harts Lake Rd.
> Battle Creek, MI 49015
> E-mail: anatechnet-link.net
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