JACK WEINBERG. Greenpeace Toxics Campaign. References. 1. Thomas V, Spiro T. An estimation of dioxin emissions in the United States. Toxicol Envi-.
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pages 298 and 299 and the corresponding description of items is potentially confusing. What is depicted in the photo was collected in a red biohazardous waste bag, perhaps reflecting the ignorance and poor performance of the hospital in question. Had the items shown in the photo been segregated properly, most should not have been a part of the hospital's regulated medical waste stream, destined for incineration, but a part of its solid waste stream, or recyclable waste. Further, the items are not "dioxin-releasing," other than the suction canister. The majority of gloves used in hospitals are latex, not PVC, but some ofthe non-latex gloves on the Hospital Waste Dissected market use PVC or a chlorinated plasHealth care practitioners should be tic hybrid. Bedpans, if they are disposeducated about the by-products of able, are usually made from HDPE quality health care, and the article was (high density polyethylene). Plastic informative. Parts of the article, how- reusable bedpans are often made from PVC, stainless steel, or a biodegradable ever, are not entirely accurate. The headline implies that the issue paper material (Baxter Vernacare). is limited to hospitals. It is not. PVC is Trays used in packaging tend to be a component of the municipal solid made of a rigid thermoform polywaste stream as well, and is being styrene material (PS #6) or a polyethylburned in municipal incinerators daily. ene terphalate material (PET #1). The headline also implies that the There are a few companies, such as problem is with plastics in general, DAVOL, that continue to package when in fact it is limited to chlorinated some of their products in PVC blisters. vinyl plastics, which are not the most The red bags themselves are usually common plastic in health care wastes; made from low density polyethylene other plastics are more dominant in (LDPE #4 plastic) or LLDPE (low linear density polyethylene). the health care waste stream. Most of the waste from hospitals is After sorting thousands of pounds of hospital wastes, I can report that actually solid waste, not unlike that volumes of HDPE, PS, LDPE, and from a hotel, restaurant, or office PP plastics exceed that of PVC. For building, ofwhich 50% or more can be example, the thousands of trash can recycled, if managed well. A small perliners are most likely made of LDPE centage, 15% or less, is actually considand solution bottles of PP PVC prod- ered "biohazardous," "regulated meducts are primarily items such as IV ical waste," or "infectious waste." It will bags/tubing, respiratory therapy tub- be important to define these terms ings, patient ID bracelets and cards, because there is little agreement components of drainage bags, suction among the states, and four define medliners, surgical tubings, and some blis- ical waste as hazardous waste. The authors make several suggester packaging. The American Plastics Council (800-2-HELP/-90) has pub- tions in their Program of Action. I lished the Hospital Plastics Characteris- would offer alternative guidance, tics and Recycling Feasibility Study including: First, I suggest that in place describing hospital waste by resin type. of a "waste audit," a purchasingThe photo of "red bag" waste on focused audit would be more useful,
with that tenet and contend that to follow the authors' suggestions could threaten the health of people who will not be able to afford health care or might not have access to chlorinerelated products such as prescription and over-the-counter drugs; test kits and catheters; ophthalmic solutions and disinfectants; or oxygen tents and intravenous fluid bags. In the end, chlorine plays a major role in assisting the medical profession heal the sick. C.T. "Kip" HowLErr Managing Director Chlorine Chemistry Coundl
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keying in on supplies and products used. Often the vital information about the product, its composition, and manufacturer are on outer packaging and likely to be separated from the product in the waste stream. Moreover, sorting through waste materials is not a job for a rookie and can be a highly dangerous task. It takes much skill and experience to be able to identify the discarded health care products and their plastic resin composition. Information on how to implement waste minimization programs in health care facilities is available in two publications of the American Hospital Association, (which I co-authored): An Ounce of Prevention: Waste Reduction Strategies for Healthcare Facilities and Guidebook for Hospital Waste Minimization and Program Planning (800-
AHA-2626). HOLLIE SHANER, RN MSA
President CGH Environmental Strategies, Inc. Authors Respond
Mr. C.T. Howlett's letter continues a tradition of worry about the potential environmental toxicity of chlorinated compounds on the part of the trade association of chemical manufacturers who produce these substances. While we disagree with his characterization of our approach to the reduction of dioxin-generating compounds, we are happy to note his desire to promote a "scientific inquiry" into this issue. Medical Waste Incinerators (MWIs) are a primary source of dioxin in the environment. Mr. Howlett is quite correct when he states, as did our article, that the EPA has said that its original estimate ofMWI dioxin emissions may be too high. The evidence is clear nevertheless that medical waste incineration remains an important source of dioxin. The EPA!s continuing analysis of the sources of dioxins is not the only recent estimate appearing in the scientific literature. Thomas and Spiro found that MWIs are the second November/December 1996 * Volume Ill
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largest source of airborne dioxins in the United States,1 and according to Cohen, Commoner and others, who used a different approach, MWIs are the largest source of airborne deposition of pollutants to the Great Lakes, accounting for 48.7% of all known atmospheric inputs of dioxins and fiirans into that ecosystem.2 Further, as dioxins are extraorcinarily persistent in the environment, a background biologic burden has developed in each human on our planet. Due to the toxicity of dioxin at extremely low levels, any deliberate program that adds additional dioxin to this burden is unwise public health policy. As Mr. Howlett notes, regulations proposed by the EPA would reduce dioxin air emissions from MWIs by requiring the installation of costly pollution control devices. As we wrote, however, all of the dioxin that would be removed from stack gases by these methods would simply be transferred to soil or water. In contrast, the elimination of dioxin-generating materials such as PVC from health care use offers a less costly and more effective means to prevent the formation of these environmentally persistent pollutants. Burning PVC in incinerators does result in dioxin formation. Mr. Howlett's letter ignores the many studies cited in our article that have found a relationship between PVC input and dioxin emissions. We noted several negative studies as well, including that of Rigo et al.3 This study, as Mr. Howlett notes, was substantially funded by chlorine and vinyl plastics manufacturers. The Rigo study analyzed previously collected data from a host of incinerators of many different types, each burning different wastes under differing operating conditions. Few of these studies were designed to examine the impact of burning chlorinated wastes on dioxin emissions. Further, in Rigo's analysis, there was no ability to control for variations in equipment type, waste feed, and operating conditions, November/December 1996 * Volume III
all of which are clearly established factors in the amount of dioxin emissions. It is not surprising therefore, that due to the amount of "noise" in the data, the study could not identify a relationship between PVC input and dioxin emissions. In contrast, a host of well-designed studies discussed in some detail in our paper-from laboratory experiments, research-scale incinerators, and fullscale facilities-have produced compelling evidence to support the intuitive notion that formation of chlorinated dioxins is related to the input of chlorinated materials-especially PVC. As Thomas and Spiro (1995) show, this relationship is not confined to MWVIs but holds true across the spectrum of combustion facility types. As we pointed out, many PVC products are currently marketed at very low prices. However, as the needed PVC-free substitute health care products come to market and achieve economies of scale, most will quickly become cost-competitive. Further, we believe that when PVC's contribution to toxic pollution is factored into the equation, PVC products are, in fact, cost-prohibitive to society. Finally, we recognize, as does the American Public Health Association, that there are some health care uses for which no feasible alternative to PVC exists today; such uses, however, account for a small minority of current chlorinated plastic health care products. Hospitals and other health care institutions are being urged to institute policies that give purchase preference to PVC-free products thereby creating the incentive for suppliers to develop and produce
cost-competitive alternatives. The authors welcome Ms. Shaner's
comments and especially her suggestions, based on extensive experience, as to the probable composition of these common health care products. We agree, as well, that a standardized nomendature would be most helpful in this area. Finally, we appreciate her emphasis on purchasing audits rather than waste audits. It is just such an approach that we suggested, yet her wording is far more precise than our recommendations. We have reviewed the books cited by Ms. Shaner and would concur with her recommendation of them for the serious health professional who wishes to reduce dioxins and other persistent pollutants in medical waste. JOE THORNTON Center for Environmental Research and Conservation Columbia University
MICHAEL McCALLY, MD PHD Professor of Community Medicine Mt. Sinai School of Medicine PETER ORRIs, MD MPH Associate Professor of Medicine University of Illinois at Chicago JACK WEINBERG
Greenpeace Toxics Campaign
References 1. Thomas V, Spiro T. An estimation of dioxin emissions in the United States. Toxicol Environ Chem 1995; 50:1-37. 2. Cohen M, Commoner B, et al. Quantitative estimation of the entry of dioxins, firans, and hexachlorobenzene into the Great Lakes fiom airborne and waterborne sources. Flushing (NY): Center for the Biology of Natural Systems, Queens College, City University of New York; 1995. 3. Rigo HG, Chandler AJ, Lanier WS. The relationship between chlorine in waste streams and dioxin emissions from waste combustor stacks. Washington DC: American Society of Mechanical Engineers and Chlorine Chemistry Council; 1995.
comments and clarifications. We agree that we are not discussing "all plastics" in this article, though all chlorinated plastics are of concern in this setting. Additional letters received after deadline Though the pictures accompanying have been forward directly to the authors the artide were not of the authors' for response. selection, we appreciate Ms. Shaner's Public Health Reports
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