This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Borganelli, G.N. Articles by Henry, R.J. Search for Related Content PubMed PubMed Citation Articles by Borganelli, G.N. Articles by Henry, R.J. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Medline Plus Health Information Indoor Air Pollution Occupational Health Hazardous Substances DB NITROUS OXIDE Social Bookmarking                         What's this?

Operatory Ventilation and Scavenger Evacuation Rate Influence on Ambient Nitrous Oxide Levels

Department of Pediatric Dentistry, University of Florida College of Dentistry, PO Box 100426, JHM Health Center, Gainesville, Florida 32610-0426

R.E. Primosch

Department of Pediatric Dentistry, University of Florida College of Dentistry, PO Box 100426, JHM Health Center, Gainesville, Florida 32610-0426

R.J. Henry

Department of Pediatric Dentistry, University of Florida College of Dentistry, PO Box 100426, JHM Health Center, Gainesville, Florida 32610-0426

Investigations have shown that greater than Federally-recommended levels of ambient nitrous oxide often exist in the dental workplace. The purposes of this investigation were to examine the influences of (1) operatory ventilation rate and (2) scavenger evacuation rate on ambient nitrous oxide concentrations within a closed dental operatory. This laboratory investigation utilized a scavenging nasal mask assembly (Porter/Brown) to deliver 40% nitrous oxide in oxygen, at a total flow rate of 5 L/min, to a mannequin positioned supinely in a dental chair. Eight experimental groups were assigned based on combinations of operatory air exchange rates (0, 5, 10, or 15 room air changes per hour) and scavenger evacuation rates (18.8 L/min and 21.4 L/min). Ambient nitrous oxide levels were monitored at four locations (0, 15.3, 30.7, and 61.4 cm) from the nasal mask by means of an infrared spectrophotometer (Miran 1B). The operatory air exchange rate was measured with a flow hood (Short Ridge) and manipulated to one of the desired ventilation rates. Time-weighted average (TWA) concentrations of ambient nitrous oxide (ppm) were continuously recorded at 15-second intervals with a microprocessor (DL332F Datalogger) connected directly to a microcomputer. The results demonstrated that significantly reduced (p < 0.05) ambient nitrous oxide levels were achieved with increasing room air exchange rates and the high scavenger evacuation rate. It was concluded that operatory ventilation and scavenger evacuation rates were significant control measures available for reduction of ambient nitrous oxide to Federally recommended levels.

REFERENCES

• American Dental Association (ADA) Council on Dental Materials, Instruments, and Equipment (1980). Council position on nitrous oxide scavenging and monitoring devices. J Am Dent Assoc 101:62.[Medline] [Order article via Infotrieve]
• Brown JP, Bell S. ( 1984). Efficiency of three nitrous oxide relative analgesia scavenging systems. Dent Anaesth Sedat 13:5-7.[Medline] [Order article via Infotrieve]
• Christensen JR, Vann WF, Linville DR (1985). Measurement of scavenged nitrous oxide in the dental operatory. Pediatr Dent 7:192-197.[Medline] [Order article via Infotrieve]
• Cleaton-Jones P., Austin JC, Moyes DG, Shaw R., Crichton R. (1978). Nitrous oxide contamination in dental surgeries using relative analgesia. Br J Anaesth 50:1019-1024.[Abstract/Free Full Text]
• Cohen EN, Brown BW, Wu ML, Whitcher CE, Brodsky JB, Gift HC, et al. (1980). Occupational disease in dentistry and chronic exposure to trace anesthetic gases. J Am Dent Assoc 101:21-31.[Abstract]
• Donaldson D., Orr J. (1989). A comparison of the effectiveness of nitrous oxide scavenging devices. J Can Dent Assoc 55:535-537.[Medline] [Order article via Infotrieve]
• Eger EI ( 1985). Nitrous oxide/N2O. New York: Elsevier, 259-279.
• Gutmann L., Johnsen D. (1981). Nitrous oxide induced myeloneuropathy: report of cases. J Am Dent Assoc 103:239-241.[Abstract]
• Henry RJ, Jerrell RG (1990). Ambient nitrous oxide levels during pediatric sedations. Pediatr Dent 12:87-91.[Medline] [Order article via Infotrieve]
• Henry RJ, Primosch RE (1991). Influence of operatory size and nitrous oxide concentration upon scavenger effectiveness. J Dent
• Res 70:1286-1289.
• Henry RJ, Primosch RE, Courts FJ (1992). The effects of various dental procedures and patient behaviors upon nitrous oxide scavenger effectiveness. Pediatr Dent 14:19-25.[Medline] [Order article via Infotrieve]
• Jacobs BS, Middendorf PJ (1986). Control of nitrous oxide exposures in dental operatories using local exhaust ventilation: a pilot study. Anesth Prog 33:235-242.[Medline] [Order article via Infotrieve]
• Kugel G., Norris LH, Zive MA ( 1989). Nitrous oxide and occupational exposure: it's time to stop laughing. Anesth Prog 36:252-257.[Medline] [Order article via Infotrieve]
• McGlothlin JD, Jensen PA, Todd WF, Fischbach TJ, Fairfield CL (1989). In depth survey report: control of anesthetic gases in dental operatiries. DHHS (NIOSH) publication no. ECTB;166-llb.
• Middendorf PJ, Jacobs DE, Smith KA, Mastro DM (1986). Occupational exposure to nitrous oxide in dental operatories. Anesth Prog 33:91-97.[Medline] [Order article via Infotrieve]
• Millard RI, Corbett TH (1974). Nitrous oxide concentrations in the dental operatory. J Oral Surg 32:593-594.[Medline] [Order article via Infotrieve]
• National Institute of Occupational Safety and Health (NIOSH) (1977). Criteria for a recommended standard, occupational exposure to waste anesthetic gases and vapors. DHEW publication no. 77-140.
• Rowland AS, Baird DD, Weinberg CR, Shore DL, Shy CM, Wilcox AJ (1992). Reduced fertility among women employed as dental assistants exposed to high levels of nitrous oxide. N Engl J Med 327:993-997.[Abstract]
• Scheidt MJ, Stanford HG, Ayer WA ( 1977). Measurement of waste gas contamination during nitrous oxide sedation in a non-ventilated dental operatory. Anesth Prog 24:38-42.[Medline] [Order article via Infotrieve]
• Sher AM, Mallett J., Cleaton-Jones PE (1987). A comparison of the cyprane and samson nasal mask scavengers during relative analgesia. Br Dent J 163:111-115.[CrossRef][Medline] [Order article via Infotrieve]
• Ship JA( 1987). A survey of nitrous oxide levels in dental offices. Arch Environ Hlth 42:310-314.[Medline] [Order article via Infotrieve]
• Sweeney B., Boingham RM, Amos RJ, Petty AC, Cole PV ( 1985). Toxicity of bone marrow in dentists exposed to nitrous oxide. Br Med J 291:567-569.[Abstract/Free Full Text]
• Tannenbaum TN, Goldberg RJ (1985). Exposure to anesthetic gases and reproductive outcome. J Occup Med 27:659-668.[Medline] [Order article via Infotrieve]
• Vieira E., Cleaton-Jones P., Moyes D. (1983). Effects of intermittent 0.5% nitrous oxide/air on the fertility of male rats and the postnatal growth of their offspring. Anaesthesia 38:319-323.[CrossRef][Medline] [Order article via Infotrieve]
• Whitcher C., Zimmerman DC, Piziali RL (1978). Control of occupational exposure to nitrous oxide in the oral surgery office. J Oral Surg 36:431-440.[Medline] [Order article via Infotrieve]

Journal of Dental Research, Vol. 72, No. 9, 1275-1278 (1993)
DOI: 10.1177/00220345930720090301


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Borganelli, G.N. Articles by Henry, R.J. Search for Related Content PubMed PubMed Citation Articles by Borganelli, G.N. Articles by Henry, R.J. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Medline Plus Health Information Indoor Air Pollution Occupational Health Hazardous Substances DB NITROUS OXIDE Social Bookmarking                         What's this?