My colleagues and I are pleased to comment on the recent Focus article on art materials published in
Environmental Health Perspectives [105:284-289 (1997)]. We believe that it is important for creative individuals to be encouraged in their expression. The driving force behind an artists' quest for new and innovative means to express his or her creativity should not be unnecessarily impeded. On the other hand, a proper understanding of the materials and their hazards when used in the creation of art is necessary. Since the proper expression of likely risks is vitally important, we are concerned that individual examples may have been presented in a manner that makes them appear sensational or of concern beyond the risks expected. In particular, we believe that formula review and supervision by a toxicologist is a sound means to prevent harm to the public. Such supervision and review should be more widely practiced for a greater variety of materials.
The toxic effects exhibited by improper or excessive exposure to art materials are as varied as the materials themselves. As toxicologists responsible for art materials labeling under the Labeling of Hazardous Art Materials Act (LHAMA), we know that certain toxic chemicals cause acute effects (immediate reaction after one exposure). These are easy to spot, and warnings about acute hazards are defined by the Federal Hazardous Substances Act (FHSA), among others. Other effects, more subtle or less timely, can be delayed, and these chronic reactions that occur after multiple periods of use constitute the area of chronic health concern mandated by LHAMA. Perhaps justifiably, the author cites Monona Rossol and Michael McCann in their expressions of concern for the chronic hazards in the artistic community. Both are known in the art hazard field and have been vocal advocates of art safety for many years.
As practicing toxicologists, we understand that some effects are reversible, while others may not be unless caught in time. Some materials provide intrinsic warnings, such as odor, indicating excessive concentration while others do not. This description could continue, but the audience of Environmental Health Perspectives is well versed in the toxicologist's litany, namely, "the dose makes the poison". However, artists are often solitary workers and, as individualists, they have been known to ignore printed warnings where their art is concerned. This characterization is clear from the article, but we judge it is not as widespread as the article implies.
Many artists acknowledge that daily exposure to some materials produce minor symptoms at low levels of exposure (headache, eye irritation, etc.), while others do not. Carcinogens and reproductive toxicants, although not acutely toxic, may manifest their effects much later when the damage has been done. Because the dose makes the poison, by inference, we know that the exposure forms the basis for the dose. Both rate and route are critical. Thus, if the words on a label prevent an exposure from happening, the harm has been mitigated.
If the right dose differentiates a poison from a remedy, can the same hold true for a label? What should the artist or consumer know, how should he or she be informed, and what role will the form of communication have in creative expression? Are more regulations needed? Except to extend coverage to more products, we believe that greater formality and the larger involvement of the agency, whether the Consumer Product Safety Commission (CPSC) or the EPA is not warranted.
Under current regulations, namely LHAMA, the toxicologist (whether as a consultant or company employee) has been delegated the task of premarket approval, a role not unlike the FDA where drugs and medical devices must be assessed for safety and efficacy. Based on the information available, the toxicologist provides or confirms a label consistent with that knowledge. Where uncertainty exists, we often call on structure-activity relationship (SAR) and analogy for help. In this regard, the article references di(2-ethylhexyl) phthalate (DEHP). While acutely nontoxic, DEHP, based on the results of chronic animal bioassays, is a known animal cancer risk. Based on an unstated similarity to DEHP, an alternative material identified as "untested complex glycol ethers" is suggested to present similar risks to DEHP. The impression is given that the untested replacement is labeled nontoxic due to a lack of data. It is also possible that the nontoxic label is based on the toxicologist's professional judgment and an understanding of its mechanism of action and not on a data gap. The subject and utility of SAR analysis and the risk posed by DEHP are subjects of considerable interest. It is our view that hazard posed to society by DEHP is small and the choice of an alternative may be forced more by a concern for market share and public relations image than by a concern for the avoided cancer hazard from this widely utilized polyvinyl chloride plasticizer. It is our view that artists should have the widest choice of materials. Such freedom of choice offers an outlet in the creative process and fosters the freedom of expression the artist seeks.
The Focus article gives examples of persons who have developed sensitivities to certain materials. In our view, it is unwise to treat any art material, toxic or not, with a cavalier attitude. Proper consideration must be given to the physical, chemical, and biological properties of all materials. This is clearly the toxicologist's task under LHAMA. A number of products, including consumer products and toys, are currently being reviewed by toxicologists with both FHSA and LHAMA guidelines in mind. In contrast to the impression created by the article, we have found that foreign manufacturers must conform to LHAMA or risk their shipments being held by U.S. Customs. More than once, we have responded to an importer in search of clearance for goods. Thus, the burden is placed on the U.S. distributer or importer to assure compliance. In this way, while somewhat after the fact, improperly labeled goods may be embargoed and kept out of the U.S. marketplace.
We believe in appropriate labeling regarding conditions for safe use and reasonable disclosure of likely adverse health effects. We wish to avoid description of events that are unlikely. In our view, most consumer products, when used as intended, pose little to no increased risk of adverse health effects for the user. In fact, based on our experience, many Poison Control Center calls concern themselves with nontoxic exposures. Still, such public concerns deserve prompt and timely responses in order to allay the fears created by overly cautious labeling.
It is imperative that knowledge regarding the potential adverse effects be our ally and not our enemy. Use of potentially hazardous materials by artists under safe environmental/workplace conditions will enhance productivity and creativity. This has been demonstrated in the industrial workplace environment where materials are regulated by OSHA and precautionary measures are taken to ensure the safety of the workers. Regrettably, the article is correct when it describes some artists as solitary and unable to afford the required safety equipment.
In the community of toxicologists who actively certify art materials under ASTM D4236 and LHAMA , we believe that those materials certified under the CPSC guidelines for labeling are appropriate for their intended use and disclose the most likely potential adverse health effects. If the user (artist) adheres to the information provided, we judge that there is no increased risk of adverse health effects to the artist. Finally, when art materials are labeled appropriately, it becomes the responsibility of the consumers/users to comply with the supplied information.
Safety assessment and risk communication is a dynamic process. Our knowledge base is constantly increasing, and society's interpretation of what constitutes safety is an evolving process. As newer technology becomes available to better qualify and quantify the potential adverse effects of materials, safe and acceptable conditions for use become available and affordable for artists, whether their studios are located at homes, schools, or workplaces. Further, as toxicologists who certify compliance with LHAMA, we must reassess and recertify each unchanged art material every five years. Any changes that may have occurred in the product formulation or the state of knowledge since the initial certification are revisited. In this way, new information and concerns for safety are added to our knowledge base and to the label.
Arlene L. Weiss
Board Certified Toxicologist
Pharm-Tox, Inc.
Mahwah, New Jersey
Rudolph J. Jaeger
Board Certified Toxicologist
Environmental Medicine, Inc.
Westwood, New Jersey
I believe there are serious problems with fairness and incomplete reporting in the Focus article "Exposing Ourselves to Art," by Scott Fields [
EHP 105:284-289 (1997)].
I have three points to make. First, in this article, Fields did not adequately explore the artist's or the art faculty's responsibility for learning to use materials properly, let alone safely. His and his sources' implications are clear: there should be more regulation, and the manufacturers should be held accountable, even liable, for labeling. In fact, the American Society for Testing and Materials' Standard Practice for Labeling Art Materials for Chronic Health Hazards (ASTM D 4236) is codified as part of the Labeling of Hazardous Art Materials Act of 1988 (LHAMA). That's plenty of regulation, but both Monona Rossol and Michael McCann would have us believe that it's not sufficient. Rossol is a member of ASTM Subcommittee D01.57, Artists' Paints and Related Materials, which wrote the standard; both she and McCann were present during discussions leading to its publication. Moreover, Rossol has had every opportunity to comment and vote on subsequent revisions of D 4236. D 4236 labeling is quite sufficient, it is continually updated (unlike any law), and its success as hazard communication rests entirely in the hands of the artist or other user, whose responsibility it is to read the labels.
My second point is that neither the Consumer Product Safety Commission (CPSC) nor the ASTM have the budget to publicize the law or the standard incorporated into it. One of the ASTM's mantras is "We only write standards," as I am continually reminded by the staff manager. The ASTM does not enforce standards. The CPSC is charged with enforcing LHAMA, but has few resources to do that, let alone publicize it. The news media, including publications such as EHP, can help in publicizing the good labeling practices promulgated by the ASTM--but only if they get the complete story through thorough reporting. Again, the user of art materials must be made aware that labels on their products carry good information and that if they choose to use materials that are not marketed as art materials, it is their responsibility to find out about safe use--and not blame someone else when an adverse health effect arises from willful ignorance.
Finally, Rossol and McCann place the blame for all this in the laps of the manufacturers of art materials or consulting toxicologists. In fact, manufacturers of art materials have been bending over backwards since 1981 to deal in a scientific, timely, and accurate manner with ASTM recommendations and medical advice, to say nothing of moral or ethical issues. Furthermore, the toxicologists and other scientists who have worked with the ASTM, including numerous state departments of public health, representatives of the EPA, and the Society of Toxicologists, have all acted in the most responsible manner possible. For Fields to suggest otherwise ("Manufacturers could be compelled to test products more extensively and label them more accurately") is, I think, simply unfair.
Mark Gottsegen
Department of Art
The University of North Carolina Greensboro
Greensboro, North Carolina
I am surprised that Mark Gottsegen thinks that I should be satisfied with the art materials labeling law (LHAMA) because I have had "every opportunity to comment and vote on subsequent revisions of D 4236" and that "it [D 4236] is continually updated." He knows that no matter how we revise this standard, only the 1988 version is referenced in LHAMA. Subsequent versions have no affect on the law.
In addition, the only major revision of D 4236 that I remember was proposed a year or two after the law became effective. The manufacturers mistakenly thought they could weaken the law by removing the requirement to include their phone numbers on the label from the revised D 4236. Once it was clearly understood that the law would be unaffected by this change, the revision was easily voted down.
Gottsegen also argues that I should be satisfied with the labeling law because I was involved in its passage. He has my permission to be even more critical of me than that: I enthusiastically supported the law at that time. This was before I learned how many ways there were around, under, and through the law. And my support of the law in 1988 is proof of my good will, trust of manufacturers and toxicologists, and outright naivete at that time.
Since then I have learned. For instance:
- Products containing untested chemicals for which there is no chronic data can be labeled nontoxic even if the chemicals are closely related to known toxic or carcinogenic chemicals.
- Products containing highly toxic chemicals including lead and cadmium were labeled nontoxic if they did not leach in an ASTM acid test, despite the fact that there were no in vivo studies demonstrating that this test was valid. Only after a nursing home resident's blood showed high lead levels after she accidentally ingested one of these nontoxic ceramic glazes did some certifying toxicologists reject this test for ceramic products.
- Another version of this unvalidated acid test for art paints (D 5517) was rammed though in 1995. I did assist in getting wording into the standard indicating that it was not a substitute for animal testing. But I am no longer naive enough to assume that this acid test is not being used at this moment somewhere to justify labeling language on paints.
As Gottsegen knows, I have many other complaints about labeling, but not many complaints about Gottsegen himself. I appreciate how hard it is to chair that ASTM committee, especially with me on it.
Monona Rossol
Arts, Crafts and Theater Safety
New York, New York
I would like to correct several misimpressions in Mark Gottsegen's letter. Gottsegen stated that the Focus article did not "adequately explore the artist's or art faculty responsibility for learning to use art materials properly," and that Monona Rossol and I didn't believe that the hazard labeling regulations for art materials were adequate. Gottsegen also states that Rossol and I "place the blame for all this in the laps of the manufacturers of art materials or consulting toxicologists."
Speaking for myself, I said in the Focus article that the Labeling of Hazardous Art Materials Act of 1988 improved labeling. My comments related to enforcement of labeling of imported art materials and the labeling of products from small companies. I agree with Gottsegen that the Consumer Product Safety Commission does not have an adequate budget for enforcement and education. However, that is not the fault of the users of art materials and does not take away from manufacturers the responsibility to follow existing regulations and to manufacture the safest possible art materials. Without adequate labeling, artists cannot know the hazards and needed precautions.
Concerning the responsibility of artists and faculty to use materials properly, an extensive part of the article deals with the responsibility of the art schools to provide a safe environment, a point ignored by Gottsegen. In addition, Gottsegen well knows that education of artists and art teachers has been the major thrust of my more than 20 years of experience in this field, as illustrated by the several books and hundreds of lectures I have done on art hazards. I agree with his statement that it is the responsibility of artists to find out about the safe use of materials that are not marketed as art materials. That is why I emphasize the need for education of art students and teachers about art hazards and the need to change existing attitudes.
Michael McCann
Industrial Hygiene Consultant
New York, New York
During the public meeting that followed the first phase of the NIEHS Predictive-Toxicology Evaluation Project (1), a discussion took place regarding the status of equivocal predictions of carcinogenicity in relation to equivocal classifications of carcinogenicity. The matter was not resolved at that time. The same question resurfaced in the recent letter by Bristol et al. (2) in relation to the second (current) collaborative study. Given that the public meeting that will follow the present study will have many issues to debate (2,3) it seems worth discussing in advance how equivocal predictions should be handled.
In situations where a predictive technique has been established as providing reliable indications of the carcinogenicity of chemicals, the mechanistic basis for that success will probably be apparent. That will elevate the technique from being empirical to rational. Such a technique may sometimes make an equivocal prediction of carcinogenicity that will reflect the true situation, i.e., after balancing the evidence used by the technique, the carcinogenicity of the agent under study will be considered uncertain and an equivocal prediction will be made. If it transpires that the agent is classified as equivocal for carcinogenicity, it could be accepted that the predictive technique had correctly anticipated that outcome, equivocal being snynonymous with ambiguous, uncertain, indeterminate, puzzling, obscure. Even in that optimum situation, a generally reliable technique may be requested to venture into an area of chemistry for which it is untrained, and an equivocal prediction made under such circumstances would simply reflect the ignorance of the technique in that area, as opposed to its genuine inability to come to a firm conclusion when faced with conflicting evidence. For example, the technique may be capable of making sound predictions of carcinogenicity for organic chemicals (some of which predictions may be genuinely equivocal), but be unable to predict the carcinogenicity of, for example, inorganic chemicals or organic arsenicals. In such situations the challenge will be to distinuish informed uncertainty from ignorant equivocation.
The techniques being evaluated in the present study (1) are probably best regarded, at least initially, as being both equal and only partially validated. That will enhance their objective evaluation. In that situation the optimum conditions outlined in the above paragraph will not hold, and a healthy skepticism will be in order. Thus, to polarize the issue, it will be inappropriate to classify a technique as 100% predictive of carcinogenicity should it transpire that all of the chemicals under study are equivocal for carcinogenicity, and all of the predictions made by the technique are equivocal.
The need for this discussion is illustrated by the 17% incidence of equivocal and/or no-predictions made in the current study [87 of the toal of 510 predictions made for the 30 chemicals (3)]. Over half of this equivocal predictions emanate from 5 of the 17 techniques used, and 36% of them are associated with the four inorganic chemicals included in the study (3). Such nonrandom groupings indicate that some of the predictive techniques presently under evaluation are either under-developed, invalid, or are not generally applicable.
John Ashby
Zeneca Central Toxicology Laboratory
Alderley Park, Cheshire, United Kingdom
References
1. Bristol DW, Wachsman JT, Greenwell A. The NIEHS Predictive-Toxicology Evaluation Project. Environ Health Perspect 104(suppl 5):1001-1010.
2. Bristol DW, Wachsman JT, Greenwell A. Response. Environ Health Perspect 105:467 (1997).
3. Ashby J. Comparison of 17 methods of predicting the carcinogenicity of 30 chemicals. Environ Health Perspect 105:466-467 (1997).
In the paper titled "Is Sperm Motility Maturation Affected by Static Magnetic Fields?" (1), the authors conclude that "sperm production is unaffected because no changes were observed in testicular or epididymal weights after exposure to static magnetic fields."
This conclusion, however, is not supported by the data presented. With five animals per group and the standard deviations (SD) given (Table 2 of their paper), a calculation of the power of such comparisons is possible. With values of * = 0.05 and ß = 0.80, the minimal detectable difference (DD) is larger than the maximal observed difference (OD), for each parameter (see Table 1).
The results of the study are therefore unable to prove the nonexistence of an effect of static magnetic fields, at least with respect to the weight data.
Alexander Lerchl
Institute of Reproductive Medicine and
WHO Collaboration Centre for Research in Human Reproduction
University of Münster
Münster, Germany
Reference
1. Tablado L, Pérez-Sánchez F, Soler C. Is sperm motility maturation affected by static magnetic fields? Environ Health Perspect 104:1212-1216 (1996).
Alexander Lerchl has stated that our inference of a lack of effect of static magnetic fields on body, testis, and epididymis weights is not supported by statistical evidence. In his argument, he has calculated the power of the analytical method used for comparison between control and exposed animals and argues that the minimal difference detectable by the statistical procedure is larger than the differences found in our study. It should be clarified that his calculations are based on the assumption that a parametric test was used for comparison; the test that was actually performed was nonparametric (Kruskall-Wallis test) because the validating assumptions needed to perform a parametric test were not fulfilled. Concretely, none of the weight variables considered was normally distributed (as checked by the Kolmogorov-Smirnov test) and, moreover, for testis weight values, the variance was not homogeneous (Bartlett test, p = 0.003). In our opinion, calculating the power of a nonparametric test by using methods reserved for parametric statistical tests is inappropriate and, to the best of our knowledge, there is no reliable model for estimating the power of the former. We accept that, to avoid misinterpretation, we should have mentioned which of the variables used in our study were analyzed with each of the two tests mentioned in the statistical analysis section. In addition to the variables mentioned above, differences in percentage of sperm motility, percentage of progressive sperm motility, and wobble were also tested by the Kruskall-Wallis test. For the remaining variables a MANOVA was used.
Independently of the statistical question, we mention in the discussion section of our paper our reservations to the implications of the results concerning testis and epididymis weights based on the inconsistency of the findings reported in several works with respect to these endpoints. This led us to qualify the implications of our results concerning weight data in the abstract by expressing that "it appears that sperm production is unaffected because no changes were observed in testicular or epididymal weights after exposure to static magnetic fields," which constitutes the entire sentence quoted by Lerchl in his letter. This conclusion is enunciated in similar wording in the discussion section of the paper.
Notwithstanding this, we have also examined the testes from animals exposed prenatally and postnatally to static magnetic fields and we have failed to find alterations in their ultrastructure or in the proliferative activity of germ cells (unpublished results). This would seem to further support our findings.
Francisco Pérez-Sánchez
Department of Animal Biology
School of Biological Sciences
University of Valencia
Burjassot, Spain
Last Update: July 31, 1997