LETTERS PCBs from old paint? Dear Editor: A recent research article on indoor air concentrations of PCBs in your journal (Wallace, J. C. et al., Environ. Sci. Technol. 1996, 30, 273034) raised concerns regarding the low (~ 300 ng/m 3 ) but persistent background PCB levels found in buildings constructed before 1980. We believe that these trace PCB levels could be due to old paints present in these buildings. PCB-containing paints were commonly used in Canada and the United States from the 1930s until the late 1970s, when they were banned in both countries. During environmental assessment and remediation work at abandoned military sites in the Canadian Arctic, we found exterior and interior paint on buildings with PCB levels from 0 to 74,000 ppm (Gill, C. G. et al., Department of National Defence, Canada, 1997). We conducted several volatilization experiments on these paint samples. In one series of tests, paint removal, using a commercial forced hot air paint stripper, was found to volatilize significant (ug) levels of PCBs into the ambient air In other laboratory investigations the PCBs released by paint maintained at 70 °C and 400 ° C were trapped (-78 °C) using a flowing air (10 mL/min) The results of the 70 °C study indicated predominant volatilization of the 3-5 chloro PPR mr\op>nf*rs (GC/W*A in air levels
with total /
3 for a
0 56-g paint sample Although no direct comparison can be made with the observations presented in Wallace et al., it is clear that PCBs are volatilized from solid paint at 70 °C. In the 400 °C experiment, ug levels of PCBs were observed. The trapped volatiles did not contain chlorodibenzodioxins and furans. The principal reason we examined the issue of PCB use in paints was to determine the problems associated with the disposal of demolition debris coated with old paint. EPA has proposed amendments to 40CFR761 that allow for the disposal
of these old paints on demolition debris in engineered landfills. In ' contrast, there is currently no regulatory exemption under the Canadian Environmental Protection Act. Any solid containing 50 ppm or greater PCBs is considered a PCB solid, which is regulated for storage and ultimately destruction by complete combustion. Current demolition and landfilling practices in Canada and the United States do not screen for PCBs in old paints. At present, this waste is undoubtedly entering landfills. C. G. GILL,* B. KUIPERS, C. D. SIMPSON, V. W. M. LAI, K. J. REIMER,* W. R. CULLEN University of British Columbia Environmental Chemistry Group Vancouver, BC V6T1Z1 *Royal Military College Environmental Sciences Group Kingston, ON K7K 7B4
Certification program overlooked Dear Editor: I read the recent editorial on certifying environmental scientists (March 1997, p. 113A) with great interest and some chagrin. I am concerned that the existence of the Institute of Professional Environmental Practice (IPEP) and the Qualified Environmental Professional (QEP) credential is failing to reach out to the extent it should. There definitely is a viable and accredited certification program for environmental scientists. The Institute was incorporated as a 501 (c)3 organization several years ago as the result of member (and some nonmember) interest in a multimedia, multidisciplinary certification of the Air & Waste Management Association. Today over 700 individuals in North America, Asia, Africa, and Europe have been awarded a QER and several hundred more are waiting to take the examination. Third-party accreditation by the Council of Engineering and Scientific Specialty Boards was secured in
January 1996. Although the two-part written examination (general science and practice area) is the principal path for QEP certification, a cadre of senior professionals has been tested by oral examination while the written instrument was developed. In addition, we have instituted the Environmental Professional Intern (EPI) credential program for college graduates with no more than two years of experience. EPI candidates are given the general science written examination and can take the second practice area exam after five years' experience to become a QEP. For further information on the program, call (412) 232-0901. ROBERT L. EISENBACH, JR., QEP President, Institute of Professional Environmental Practice Pittsburgh, PA 15222
Corrections The feature article, "Phytoremediation on the Brink of Commercialization" (April 1997, pp. 182A-186A), incorrectly attributed research on selenium volatilization rates of crop species to G. Banuelos. The research mentioned on p. 184A was conducted by Norman Terry and colleagues at the University of California, Berkeley (Terry, N. et al. /. Environ. Qual. 1992, 21, 341-44). Our April 1997 news story, "MTBE water concentrations raise health concerns, research questions" (p. 176A), incorrectly stated the MTBE exposure level of EPA researcher James Prah's planned human inhalation study. The study will use 3 ppm MTBE, not 30 ppm. Readers are encouraged to comment on articles published in ES&T and on other issues facing the environmental community. Contributions are limited to 500 words. Send Letters to the Managing Editor within two months of the date of publication of the original article. Submissions are subject to editing for clarity and length.
VOL. 31, NO. 8, 1997 / ENVIRONMENTAL SCIENCE & TECHNOLOGY / NEWS • 3 4 3 A
