Prospective study of clinical symptoms and skin test reactions in medical students exposed to formaldehyde gas

Abstract

Previous investigators have reported the occurrence of both allergic and non-allergic systemic complications due to exposure to formaldehyde gas. However, little is known about the pathogenic link between formaldehyde-induced clinical symptoms and patch test results, or about the long-term effects of formaldehyde exposure. In the present study, a questionnaire was administered to 143 medical students, and 60 of them were tested by patch test for formaldehyde at the beginning and end of a human anatomy laboratory course. Another group of 76 students who had finished the course 2-4 years previously were administered another questionnaire, and the patch test was carried out on 58 of them. The frequencies of skin irritation, eye soreness, lacrimation, eye fatigue, rhinorrhea, throat irritation, general fatigue and mood swings increased after repeated exposure. Two (3.3%) of 60 students became positive to 1% formaldehyde at the end of the anatomy course (one male with allergic hand dermatitis due to direct contact with formaldehyde, and one female with an atopic background with unbearable physical symptoms) while the remaining 58 showed a negative reaction throughout the study period. The vast majority of students complained of various non-allergic, physical symptoms, and recovered from such symptoms without subsequent complications. No progression to multiple chemical sensitivity was found. Students with an episode of atopic dermatitis and allergic rhinitis were susceptible to formaldehyde exposure, and developed mucocutaneous symptoms, probably due to the impaired barrier function and remodeling of the skin and mucosa.

Health risk assessment of exposure to formaldehyde in dental materials

“…The irritant action of formaldehyde on eyes, upper respiratory tract and skin is well documented [4,[14][15][16][17][18][19][20]. Our results indicate increased incidence, with a high significance, and relative risk of manifestation of subjective symptoms from the upper respiratory tract, respiratory system and the skin in the group of dental professionals.…”

“…The irritant action of formaldehyde on eyes (watery, itchy eyes), upper respiratory tract (itchy, runny, or stuffy nose, sinus fullness, dry or sore throat) and skin (irritation and dermatitis) is well documented [4,[14][15][16][17][18][19][20].…”

Formaldehyde-related clinical symptoms reported by medical students during gross anatomy cadaver dissection

“…Prolonged exposure to formaldehyde is commonly associated with both allergic and non-allergic systemic complications [3]. Formaldehyde toxicity is related to mucosa irritation, particularly to the eyes and to the upper respiratory tract [4,5]. Acute clinical symptoms include headache, dermatitis, and asthma [6].…”

“…The course program includes fresh cadaver dissections or prosections [11,12]. During these dissection classes, medical and dental students are exposed to formaldehyde vapors emitted from cadavers [3,4]. Inhalation is considered to be the primary route of exposure; however, the area of formalin absorbance includes the lungs, gastrointestinal tract, and skin [13,14].…”

Toxicological effect of formalin as food preservative on kidney and liver tissues in mice model

“…However, it is inadequately absorbed following dermal contact. Its main routs of exposure in our environment are air (through occupational exposure like as formaldehyde and resin production), smoking (receiving about 0.38 mg/day) [7], dermal exposure [8], [9] and also through water. Formalin can also be administered through food and drinking water naturally and artificially when used as food preservative [10], [11].Annual production of this hazardous chemical varied from 6.4 to 8.1 billion pounds per years "between" 1991-1995 in the U.S [3].…”