Please select a topic to see a list of frequently asked questions, and Dow’s answers.
Animals in Research
Q: Why does Dow use laboratory animals for research?
A: Animal testing is not something Dow undertakes arbitrarily, but neither is it something Dow can discontinue, as this testing plays a critical role in enhancing Dow’s understanding about the safety of Dow’s products, thereby protecting public health and the environment. Indeed, in almost all cases the laws of the countries in which Dow operates require such testing to be conducted. As far Dow is able, Dow keeps its use of animal testing to an absolute minimum.
Dow is continually looking for reliable alternatives to animal testing that meet Dow’s product stewardship requirements. Dow supports the 3R’s — reduce the use of animals, replace them with non-animal test methods, or refine test procedures to eliminate animals’ pain and distress. Dow is working to integrate alternative methods into Dow’s product safety evaluations where their use will not compromise human health or safety and where they will gain acceptance from regulatory agencies.
Since 1968, Dow has voluntarily been audited by the Association for the Assessment and Accreditation of Laboratory Animal Care (AAALAC). Following each audit, Dow has been accredited by AAALAC.
For more information about Dow’s judicious use of laboratory animals in testing, visit Animal Research.
Chemical Exposure and Asthma
Q: There is a well-recognized increase in the prevalence of asthma in children. Meanwhile, more chemicals have entered commerce. What does Dow know about the alleged link between chemical exposure and asthma?
A: The use of manufactured chemical products has generally increased over the years and in turn has contributed to our improved lifestyle, from new medicines to cleaner water, more energy-efficient cars, and affordable housing. While the number of children and adults suffering from asthma has increased, there is no scientific consensus that chemicals are among the major causes. According to the US Centers for Disease Control and Prevention, smoke from tobacco products, dust mites, outdoor pollution, cockroaches, pets, and mold are important triggers for asthma. Strenuous exercise, adverse weather, certain food or food additives and other stimuli also can trigger asthma.
There are a limited number of manufactured chemical products that can trigger and/or worsen asthma and/or respiratory allergy. The uses of such chemicals are generally well controlled and regulated to limit the exposure. As a result, these substances are not usually associated with asthmatic reactions in the general public. Although a role for some types of chemical exposure cannot be ruled out, the direct contribution of chemicals is likely small compared with other lifestyle and environmental factors.
The knowledge that specific chemicals might bring about asthmatic conditions gives Dow cause for vigilance when it comes to product stewardship and the marketing of substances. In our role as a chemical manufacturer, we assess the hazards of our products. This is part of the overall evaluation using Dow's Product Safety Assessment process.
Credibility of Industry Science
Q: Why should we trust any science coming from the chemical industry, and especially from Dow?
A: Chemicals are among the most thoroughly evaluated and regulated materials in commerce. Chemicals are developed, manufactured, distributed and used under a strict and comprehensive set of government rules. Dow takes very seriously its responsibility to protect people and the environment throughout the life cycle of our products, from manufacturing to disposal/recycle. Commitment to this responsibility is evident in our 2015 Sustainability Goals. That commitment includes conducting research, modeling and laboratory studies to fulfill both product stewardship responsibilities (as outlined in the industry principles of Responsible Care®) as well as voluntary goals and objectives that enhance product safety. The research, modeling and testing conducted by our scientists provides required information for risk assessments to ensure that our chemical products can be used safely. This information is obtained in a manner which complies with international and local regulatory requirements further establishing the reliability and credibility of industry science.
In recent years some have questioned the reliability and credibility of public health and environmental research conducted and/or funded by the chemical industry in general and Dow, specifically. Such opinions, however, fail to recognize that studies conducted and funded by Dow have long been and continue to be recognized as valid and credible by government agencies, non-governmental organizations, and the scientific community at-large. Studies conducted and funded by Dow are necessary and valuable contributions to the understanding of potential public health and environmental effects related to the manufacture and use of its products. Several procedures have been established that authorize independent review of scientific studies, in order to assure that the quality and credibility of studies conducted or funded by Dow meet the highest scientific standards. The practices and procedures by which policymakers and the public can be assured that studies performed by or funded by Dow meet scientific high standards include:
- All studies required by governments are conducted in accordance with Good Laboratory Practice (GLP) regulations which require full availability of the recorded, quality-assured data files1 and which allow for unannounced audits by government authorities, such as the FDA or EPA. Dow also follows GLP requirements voluntarily for many other studies that it conducts.
- An internal Quality Assurance Group reports independently of day to day laboratory management and audits all studies conducted to ensure compliance with GLP regulations. Employees also undergo training to understand the requirements of GLP regulations.
- Studies are conducted according to internationally agreed upon protocols and test guidelines.
- Scientists are encouraged to submit their results in the peer-reviewed scientific literature and to present them in scientific forums.
- All research involving human subjects is reviewed and conducted to comply with generally accepted ethical standards and requirements. This includes the Common Rule, the Nuremberg Code, the Declaration of Helsinki, and any other applicable local government requirements and guidelines which are at least equivalent to those provided by the Common Rule.
- All animal studies are conducted in full compliance with state and federal animal welfare regulations. In addition, Dow is accredited by the Association for Assessment and Accreditation of Laboratory Animal Care International, an achievement recognized as the highest attainable by the animal care profession.
- Studies that demonstrate adverse effects are made publicly available in a timely manner to comply with the U.S. laws of TSCA 8e and FIFRA 6a2 or similar equivalent regulations in other countries.
Dow firmly supports and has full confidence in these processes. Research studies that adhere to GLPs deserve the very highest degree of confidence regarding (1) the specific and detailed experimental protocol design, (2) the measurements taken, and (3) the accuracy of the reported results because all of these elements must meet GLP quality control and quality assurance requirements. Moreover, studies based on regulatory requirements use standardized methods that have been scientifically validated and approved by regulatory bodies. Finally, GLP studies facilitate transparency and the ability of others to reproduce the test results.
Dow is strongly committed to the safe manufacture, use, and disposal of its products. Our scientists have expert knowledge of the chemicals we manufacture, especially as this relates to the development and interpretation of the science needed to comply with the laws and regulations of the chemical industry on a global basis. As members of professional associations, our scientists adhere to both personal and professional commitments to act in accordance with codes of ethics of their professions2. Finally, research should be judged on the basis of scientific merit, without regard for funding source or where the studies are conducted (e.g. academia, government, or industry)3.
1Furthermore, of the various types of data and information employed in risk assessment, GLP derived data will most readily meet the requirements of the Information Quality Act (USEPA 260/R-02-008. Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility, and Integrity of Information Disseminated by the Environmental Protection Agency, October, 2002). See http://www.epa.gov/QUALITY/informationguidelines/
3Conolly, R.B., Beck, B.D., and Goodman, J.I. (1999). Stimulating research to improve the scientific basis of risk assessment. Toxicological Sciences, 49, 1-4.
Dose Response Assessment
Q: Some scientists are saying that very low doses of chemicals can have an even greater effect on our bodies and that the industry science that Dow practices isn’t picking that up. What do you say?
A: One of the basic tenets of toxicology is “the dose makes the poison.” That is, as a dose increases, the likelihood of a toxic response increases as well.
Recently, some scientists have challenged this well-established tenet with a new hypothesis, that low doses of chemicals — below those that have previously shown no hazardous effect — are actually causing previously unrecognized toxicity. They are arguing that there is a low-dose effect of chemical exposure.
However, their science has not held up to scrutiny. When the scientific methods followed by these scientists were subject to a repeated study, the results were unable to be replicated. Thus, the low-dose hypothesis remains just that — an hypothesis that should be subjected to the scrutiny of scientific peers.
An alternative hypothesis is that low doses of chemicals can actually have a beneficial effect. This hypothesis, called “hormesis,” suggests that a substance that is harmful at high exposure levels can be beneficial at low levels. Although there is some limited evidence to support the hypothesis of hormesis, this concept remains as controversial as the low-dose theories of toxicity.
Dow believes that the weight of evidence supports the idea that low exposures to chemical substances present in the environment do not pose a significant risk of adverse effect. We remain open to scientific advances that will help better inform the regulatory process so that human populations can be adequately protected, while taking advantage of the benefits that modern chemistry can provide.
Q: How much do you know about the use of your products or their foreseeable misuses? And how much do you know about how people are getting exposed to your chemicals?
A: Much of our information about exposure to our products comes from our experience with our own employees in our manufacturing facilities or in our customer facilities. Dow has had considerable experience conducting industrial hygiene surveys during the manufacture and use of our products. We also learn from the experience of government agencies and professional societies, as well as the experiences of other companies.
Dow seeks information about the use and potential misuse of our products through dialogue with our customers, distributors, and other downstream users of our products. Commensurate with product risk, Dow seeks to gather information about the use of its products. For products with higher hazard, we inquire about the end use, handling, storage, transport and disposal of substances to ensure that our customer is aware of the potential hazards and has appropriate risk management measures in place. Dow’s ongoing dialogue with downstream partners is an essential element to the continuous improvement of our product stewardship practices.
Dow educates and trains employees, based on their job function, on the proper handling, recycling, use and disposal of products and known product uses. We have a system that encourages employees, such as our sales force and technical service personnel, to feed back information on new uses, identified misuses or adverse effects for use in our product risk characterizations.
Q: Does Dow test its chemicals on people?
A: It is rare that Dow would undertake such testing. Human subjects research can, however, help to inform an understanding of the possible interactions that chemicals can have with humans. Human studies can be more representative and useful than animal tests in determining health outcomes, establishing no observed effect levels, and studying mechanisms of toxicity. However, human subjects research is accomplished only under strict protocols, after other testing methods have been utilized.
Human studies generally fall into two categories: (1) human clinical studies, in which volunteers are deliberately exposed to substances, and (2) field epidemiological or exposure studies, in which data are collected about populations measured under natural exposure conditions.
Ethical standards have been established by the US government and several international bodies to protect the participants in human subjects research and to convey that information to prospective test subjects prior to obtaining their consent.
Dow supports the American Chemistry Council’s “Policy on Human Subjects Research” which states: “All research involving human subjects will be conducted in accordance with either the Common Rule, the Declaration of Helsinki or the Guideline for Good Clinical Practice, depending on the entity or entities to which the research results may be submitted and other relevant factors.”
Q: Dow says that they are committed to understanding the possible risks of their products. But most of their tests are conducted on single chemicals, when everyone knows we’re exposed to a sea of chemicals — mixtures of chemicals — every day. Aren’t these mixtures more dangerous than the single chemicals?
A: Existing research indicates that mixtures of chemicals are unlikely to cause adverse effects when all of the individual chemicals are at safe levels. Dow therefore considers that a single chemical risk assessment approach – as required by existing regulatory schemes - is in most cases sufficiently protective of human health and the environment. However, in situations where screening assessments identify exceptions to this general rule, Dow supports the use of cumulative risk assessments to further evaluate the safety of the combination of chemicals. In fact, Dow researchers have contributed new methods to the scientific community to help prioritize mixtures for more detailed evaluation so that resources are applied where they are needed most.
Humans have been exposed to the effects of combinations of chemicals (so-called ‘mixtures’) from the beginning of our existence. The food we eat, the air we breathe, and the products which we come into contact with every day are complex mixtures containing various man-made and naturally occurring chemicals. Nonetheless, chemical safety for the majority of chemicals has been based on the evaluation of single chemicals for a variety of reasons including the infinitely large number of possible chemical combinations, which would make a complete description of individuals’ exposures difficult if not impossible to determine and would include many compounds with little or no toxicity. Ongoing questions about the potential toxicity of mixtures (also referred to as ‘cumulative risk’) have resulted in governments in the EU and North America addressing whether existing regulation is sufficient, and considering suitable alternatives.
For several years, Dow has been engaged in advancing science-based approaches to assess the potential effects of combined exposure to multiple chemicals, including addressing the question of potential additive and synergistic effects of chemicals. This has led to Dow scientists developing new tools and frameworks to assess mixtures, including the Maximum Cumulative Ratio (MCR) screening tool. The use of the MCR screening tool - using basic exposure data and very cautious default assumptions (e.g., dose additivity) - enables the identification of those mixtures of greatest concern for which a cumulative risk assessment would be needed. The MCR provides guidance on a mixture’s toxicity, or the cumulative risk missed by a single chemicals risk assessment approach. The MCR values also indicate the fraction of toxicity that comes from the most toxic component of the mixture.
In addition to the MCR screening tool, Dow has contributed to the science of mixture toxicity by developing economical designs for mixtures investigations including mixtures statistics, and cell culture techniques. Dow is currently working with various academic and industry organizations to apply the MCR approach to investigate real-world mixtures of chemicals to identify when exposure to mixtures of chemicals are a concern. The entire suite of tools has been organized into a tiered “Decision Tree” framework by the European Chemical Industry Association (Cefic). Dow continues to share the work on the MCR and on the Decision Tree framework with industry, government and other stakeholders in various science and policy forums.
Based on research conducted to date, it appears that the toxicity of many mixtures encountered by individuals in the real world is usually driven by one or just a few chemicals within the mixture.
Furthermore, it also seems that the toxicity of mixtures which pose harm to human health and/or to the environment, appear to be driven by the toxicity of a single chemical within the mixture. Based on these findings, it is possible to take targeted action on the individual chemical posing the problem, rather than attempting to take action on a multitude of potentially harmless substances.
In summary, Dow considers that combined effects are unlikely when all of the chemicals of the mixture are at safe levels, which is often the case in real-world mixtures. Consequently Dow believes, as a general rule, a single chemical and source by source risk assessment approach to be an effective means for identifying the drivers of risk of a mixture. Dow also believes that existing regulations – such as EU REACH or global Plant Protection Regulations, which utilize large safety factors to keep exposure low - are sufficiently protective of human health and the environment. In those cases where tiered screening assessments such as the MCR identify exceptions to this general rule, a cumulative risk assessment should be used to further evaluate the safety of the mixture.
Below is a listing of selected Dow publications on this topic.
- Paul S. Price and Xianglu Han (2011). Maximum Cumulative Ratio (MCR): A Tool for Assessing the Value of Performing a Cumulative Risk Assessment, International Journal of Environmental Research and Public Health 8: 2212-2225; doi:10.3390/ijerph8062212
- Boobis A, Budinsky R, Collie S, Crofton K, Embry M, Felter S, Hertzberg R, Kopp D, Mihlan G, Mumtaz M, Price P, Solomon K, Teuschler L, Yang R, Zaleski R. (2011). Critical analysis of literature on low-dose synergy for use in screening chemical mixtures for risk assessment. Crit Rev Toxicol. 41:369-83.
- P.S. Price. Synergy a Risk Management Perspective. In The Principles and Practice of Mixtures Toxicology. Wiley-VCH. Ed. Moiz Mumtaz, 2010
- Carney, E.W., Woodburn, K. and Rowlands, J.C. (2010). Endocrine Active Chemicals. In: Principles and Practice of Mixtures Toxicology. Mumtaz, M. (ed.). Wiley-VCH Verlag GmbH & Co. KGaA, Germany. pp. 421-442.
- Price PS, Hollnagel HM, Zabik JM (2009). Characterizing the noncancer toxicity of mixtures using concepts from the TTC and quantitative models of uncertainty in mixture toxicity. Risk Analysis 29:1534-48.
- Price P, Wiltshire G. (2009). Modelling the chronic non-cancer effects of mixtures of migrants using Cramer classes and quantitative models of uncertainty. Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 26:1547-55.
- Stork, L.G., Gennings, C., Carter, W.H. Jr., Teuschler, L.K. and Carney, E.W. (2008). Empirical evaluation of sufficient similarity in dose-response for environmental risk assessment of chemical mixtures. J. Agric. Biol. Environ. Statistics 13:313-333.
- Charles, G.D., Gennings, C., Tornesi, B., Kan, L., Zacharewski., T.R., Gollapudi, B.B. and Carney, E.W. (2007). Analysis of the interaction of phytoestrogens and synthetic chemicals: An in vitro/in vivo comparison. Toxicol. Appl. Pharmacol. 218:280-288.
- Teuschler, L., Klaunig, J., Carney, E., Chambers, J., Conolly, R., Gennings, C., Giesy, J., Hertzberg, R., Klaassen, C., Kodell, R., Paustenbach, D. and Yang, R. (2002). Support of science-based decisions concerning the evaluation of the toxicology of mixtures: a new beginning. Reg. Toxicol. Pharmacol. 36:34-39.
Q: It seems as if the incidence of autism, ADHD, learning problems, and Alzheimer's disease are on the increase, while the number of industrial chemicals has also increased. Are chemicals causing this epidemic of neurobehavioral problems? What is Dow doing about it?
A: The rates of some neurobehavioral diseases in children and adults do appear to be increasing, while others have stayed the same or are decreasing. Scientists urge caution in interpreting any disease trends. Before concluding that such trends are real and investing in expensive research to determine the factors that may be causative, scientists must evaluate whether changes in diagnostic methods, disease classification or reporting practices might cause artificial changes in disease rates over time. Further investigation is especially important for diseases such as autism, for which the causes are still largely unknown. Dow supports efforts to strengthen and standardize health and environmental data collection efforts internationally so that trend data can be analyzed and used for further investigation, but we believe it is premature to link diseases such as autism and ADHD to chemicals without further rigorous scientific investigation.
POPs and PBTs
Q: I hear a lot about POPs and PBTs showing up in animals and people. How does Dow address this issue?
A: Certain substances are classified by different regulatory bodies as POPs (persistent organic pollutants) and/or PBTs (a broader category of substances that are persistent, bioaccumulative and toxic). These substances have generated a range of public health and environmental concerns. But in its Third National Report on Human Exposure to Environmental Chemicals, the Centers for Disease Control and Prevention (CDC) is careful to point out that the measurement of an environmental chemical in a person's blood or urine does not by itself mean that the chemical causes disease.
We are committed to promoting a science- and risk-based approach to manage the risks associated with PBTs throughout the product life cycle. We work hard to ensure our products are manufactured, stored, transported, used, disposed and recycled in a manner that shows high regard for human health, safety and environmental stewardship.
Dow’s business decisions are based not only on the anticipated benefits of the product, but also on a careful assessment of potential effects on human health or the environment with respect to exposures. Our Business Environment, Health & Safety (EH&S) Risk Review Work Process has been designed to meet, among other obligations, various management practices of the American Chemistry Council’s Responsible Care® program. It also helps Dow to meet requirements of the Responsible Care codes of chemical industry associations in countries outside of the U.S.
Dow's approaches for evaluating P, B and T characteristics of substances are consistent with those proposed internationally, regionally, and nationally. We are collaborating with governments and other scientists on research to refine and improve upon these approaches.
Dow strongly supports the Stockholm Convention. We are actively involved in other international and regional PBT efforts being addressed by multi-stakeholder, international groups through the United Nations Environmental Programme (UNEP), United Nations Economic Commission for Europe (UNECE) and the U.S./Canada Great Lakes Bi-national Toxics Strategy.
Q: Risk assessment seems to say that it’s okay to cause cancer among a few people. Doesn’t Dow support preventing bad things from happening?
A: Dow supports taking precautionary action to protect human health and the environment.
Dow supports a precautionary approach as set out in Principle 15 of the Rio Declaration on Environment and Development: “In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities. Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation.”
The Rio Declaration was amended at the Johannesburg summit to include health impacts, in addition to environmental impacts.
Dow believes that measures should be risk-based and cost-effective. Additionally, the selected chemicals management measure should be:
- proportional to the objective being pursued
- the least burdensome option that provides adequate protection from the risk
Q. How do you prioritize the products for your product safety assessments (PSA's) and your goal timeline?
A. Products are prioritized for this goal according to the following order (subject to change as conditions warrant):
- Products subject to a deadline in a regulatory program such as those that are a priority under REACH (produced in volumes greater than 1000 tonnes annually); all products subject to an existing European Union or U.S. Environmental Protection Agency (EPA) risk assessment; all products on the U.S. Integrated Risk Information System (IRIS) Priority List; any substances likely to be subject to authorization under REACH (e.g., carcinogens, mutagens or reproductive toxicants (CMRs), persistent organic pollutants (POPs), persistent, bioaccumulative and toxic compounds (PBTs), compounds that are very Persistent or very Bioaccumulative (vPvB), and Endocrine disruptors).
- Products produced in volumes greater than or equal to 100 tonnes annually; products sold into applications with greater potential for exposure; or more hazardous products.
- The company wants to elevate the priority of a material for other reasons.
- All products produced and sold in volumes greater than or equal to 1 tonne annually.
It is Dow's intent to complete PSAs for all products that fall into category 1 by year end 2010 and all other products by 2015.
Layers of Protection for Children
Q: Because children are known to be more vulnerable to chemical exposures, shouldn't we automatically impose higher levels of safety to protect them?
A: Dow supports the accumulation of information to support risk-based decision making to protect the health and safety of all populations, including children (and others considered to be more sensitive sub-populations). That is why Dow is participating in the US EPA Voluntary Children's Chemical Evaluation Program (VCCEP). This tier-based risk assessment program is focused specifically on ensuring adequate protection for children from certain substances to which children may be exposed.
Current risk assessment practice incorporates precautionary (or safety) factors to accommodate scientific uncertainties. Typically, a 10-fold safety factor is applied to accommodate the uncertainty of extrapolating findings from studies conducted in laboratory animals to humans. An additional 10-fold safety factor may then be applied to allow for variability or unique sensitivities among humans.
Scientists have examined the question of unique or greater vulnerability of children and have concluded that, while there are some examples of chemicals and exposure scenarios where children are more vulnerable, there are many more examples where they are not. Their conclusion is that because we cannot automatically conclude that children are more vulnerable to the effects of chemicals, decisions to impose additional safety factors, beyond the two ten-fold safety factors discussed above, should be made on a case-by-case basis, taking into account the inherent hazards of the chemical, exposure scenarios and the weight of the scientific evidence.
Dow supports efforts to strengthen and standardize health and environmental data collection efforts internationally so that children's disease trend data can be analyzed and used for further scientific investigation. We support continued research into the causes of childhood morbidity and mortality using rigorous scientific methods, such as those outlined in the US National Children's Study. We caution against drawing “cause and effect” conclusions from studies that are intended to merely link health and environmental databases.