“Lists of EDCs”: Understanding Major Limitations of Many Chemical Lists – TEDX List, SIN List, Danish EPA List, and REACH SVHC List
Lists are among the simplest and most widely used tools today. Sometimes, we make lists ourselves, like to-do lists and grocery lists. The internet and health magazines especially are full of these “lists” that appear to be expert recommendations on things to avoid or use, like “10 foods to avoid” or “top 10 superfoods.”
Rather than take a list at face value, however, it’s important that we all ask some basic questions about the quality of information that goes into the lists; whether they’re kept up-to-date; and whether they’re actually being interpreted and used properly.
In 2016 United Nations Environment (UNE) commissioned the International Panel on Chemical Pollution (IPCP) to research and identify every “list of EDCs” that had been published to date. We highlight four chemical lists from the UNE-IPCP report that demand further scrutiny: The Endocrine Disruptor Exchange (TEDX) list; the SIN (Substitute It Now!) list from the International Chemical Secretariat (ChemSec); the Danish Environmental Protection Agency (Danish EPA) list; and the EU REACH Substances of Very High Concern (SVHC) list.
Developing lists of chemicals for regulatory purposes
Regulators can rely on lists, too. For example, in response to questions about whether certain environmental chemicals may interfere with the endocrine system and cause negative effects, government and scientific bodies have been working to distinguish between whether a substance is merely endocrine active, or whether, under certain exposure scenarios, a substance goes beyond a simple interaction that is reversible and causes no harm to one that results in adverse health effects – endocrine disruption.
Lists come into play by helping regulators prioritize chemicals to screen and test for endocrine activity and potential endocrine disruption. At the U.S. Environmental Protection Agency (EPA), for example, regulators rely on two lists to help the EPA implement its widely respected Endocrine Disruptor Screening Program (EDSP).
In publishing these screening lists, EPA has been careful to highlight several key points for policymakers and the public:
- The lists are not “lists of endocrine disruptors.” EPA selected and prioritized the chemicals based on exposure potential, or how our bodies might come into contact with the substances. EPA decided to start its screening process by looking at several chemicals based on the quantities manufactured annually. Many of the substances on EDSP List 1 are “High Production Volume” – they are produced or imported into the U.S. in quantities of at least 1 million pounds per year.
- EPA did not select the chemicals because they were suspected, suggested, or potential endocrine disruptors. As the EPA makes clear, the chemicals “should not be construed as a list of known or likely endocrine disruptors. Nothing in the approach for generating the initial list provides a basis to infer that by simply being on this list these chemicals are suspected to interfere with the endocrine systems of humans or other species, and it would be inappropriate to do so.”
The U.S. EPA in fact has no list of “endocrine disruptors” at all – preferring to assess chemicals on a case-by-case basis; taking into account the entire body of toxicological evidence available; and factoring in actual human exposure levels.
When “chemical lists” veer off course
Of course, not all chemical lists are explained with such care and clarity of purpose. Chemical lists can be created by politicians in legislation without a scientific basis at all. Lists can be created by regulators under different laws with different criteria. Yes, chemical lists can be created and published by virtually anyone with a computer or pen and paper – including non-scientists and non-regulators. Some chemical lists are misused and mischaracterized as definitive science on EDCs, or as definitive classifications of EDCs.
Here are some common issues with “chemical lists” that may or may not be clearly explained by their authors:
| Problem Area | Consequence |
|---|---|
| Inconsistent definitions and criteria | Inconsistent use of definitions and criteria across lists results in chemicals with endocrine activity only (or no endocrine activity at all) being “listed” as an EDC. In addition, when several different lists that use varying definitions and criteria are combined, the resulting data is tainted. |
| Hazard-only approach | Hazard-only approaches do not consider real-world exposure scenarios and factors like potency. Sunlight, soy and water are all hazards under some conditions, but that does not mean they pose a risk under all conditions. Lists that are informed by hazard only are not suitable for regulatory decision making. |
| Ignores scientific detail | Lists often carry a veneer of authority that masks the relatively unscientific methods by which they were created. As a result, the public and policymakers may wrongfully assume that each chemical listed was done so based on equally valid and robust science, and that each chemical is equally potent and poses equivalent risk, when the opposite might be true. |
| Causing regrettable substitutions | Lists are problematic not only for the substances they inappropriately reference, but also for the ones they don’t. Some might believe that the absence of a chemical from such lists is evidence that a chemical is safe, when in reality that substance may not have been assessed. This can lead to chemicals that have years of safety research being pulled from the marketplace and substituted with substances for which far less safety information may exist. |
One of the goals of this webpage is help the public, media and policymakers understand why many of the most often cited “lists of EDCs” lack credibility and authority – and therefore, are not suitable for use in private sector standards and certification programs, purchasing decisions, or in regulatory decision-making.
To the astonishment of many, IPCP found not 5, not 10, not 15… but 24 self-identified “lists of EDCs” floating around in the public sphere, essentially diluting the meaning or relevance of all of the lists.
Wild, Wild West: UN Environment Commissions IPCP to Corral Every Published “List of EDCs” For Review
In 2016 United Nations Environment (UNE) commissioned the International Panel on Chemical Pollution (IPCP) to research and identify every “list of EDCs” that had been published to date – including from governments, private groups, and others – and compile them into a single chemical database. The final report, dated July 2017, was published in July of 2018.
To the astonishment of many, IPCP found not 5, not 10, not 15… but 24 self-identified “lists of EDCs” floating around in the public sphere, essentially diluting the meaning or relevance of all of the lists.
One surprising finding of the project was that many of the chemical lists were not created independently of one another – meaning, some lists were based on other lists, which may have been based on other lists still, and so on and so forth.
The inter-dependent, almost “incestuous” nature of the lists might have initially given the impression that the creators of the lists independently reached the same conclusion about the substances appearing on those lists, when, in reality, the perceived agreement between separate sources doesn’t exist at all – it may all be the same original source.
Another finding of the project was the apparent failure of the lists to meet specific criteria that would indicate whether they were scientifically credible. For example, at least 9 issues contributed to the overall unreliability and lack of utility of the lists included for evaluation in the draft UNE-IPCP report:
- In many cases, the initial pool of chemicals from which the substances were selected was either not described explicitly, was overly broad or too narrow to be useful.
- The selection criteria for designating a compound as EDC or potential EDC were not consistent.
- The authors of some of the lists lacked the requisite training and expertise to accurately assess the quality and reliability of the available scientific studies.
- The underlying scientific studies on which some decisions to identify a substance as an EDC lacked the necessary quality and reliability.
- Many of the lists were redundant and self-referential (i.e., some lists were derived from other lists, giving a false impression of independence and concordance).
- The stated purpose of the lists differed (e.g., some were intended to consolidate knowledge, others to prioritize chemicals review, and still others to identify EDCs/potential EDCs).
- Some lists lacked the opportunity for multi-stakeholder input.
- Some lists were unable to be updated based on new scientific information.
While UNE’s intent was to use the report as an educational tool designed to serve policymakers and the public, the project essentially backfired when stakeholders from around the world submitted comments on the draft report, offering detailed explanations as to why several of the lists – including the REACH SVHC List and Danish EPA List – could not be relied upon for use outside their specific public (governmental) purpose. The SIN List – maintained by a private group called The Endocrine Disruptor Exchange (TEDX) – is so riddled with limitations that it should not be used at all.
The Endocrine Policy Forum (EPF), a consortium of scientific and regulatory experts coordinating industry participation in the EPA Endocrine Disruptor Screening Program, best summed up stakeholders’ critical comments on the project in general:
“The approach taken in the IPCP report does nothing to further the science or understanding of endocrine disruption. Compiling lists that were developed for different purposes, that are not specific for potentially endocrine active chemicals, that utilize different methodologies and criteria for designating a chemical as endocrine active or an endocrine disruptor, and do not require appropriate data quality or standard guidelines to conclude on endocrine activity serves no purpose, and is not a scientifically responsible means to educate regulatory authorities or the public.”
The final UNE-IPCP report addressed some, but not all of the criticisms that were leveled at the draft. Importantly, it does include the following cautionary statement about chemicals identified as EDCs from the Danish EPA List or the SIN list:
The chemicals which appear in this table have not been identified as known or suspected EDCs as part of a regulatory review which considers and weighs all available evidence, engages external peer review and is open and responsive to public review and comment.
In discussions with UNE staff it is clear that they understand that publication of “lists of EDCs” appearing in the UNE-IPCP report could do real damage, misleading the public by incriminating specific, high-profile chemicals and creating the impression of health risks with no scientifically reliable basis. Consequently, UNE staff insist that the UNE-IPCP report only identifies initiatives by others to identify substances that are either EDCs or Potential EDCs and not lists.
A Closer Look: Critiquing the TEDX List, SIN List, Danish EPA List, and EU REACH SVHC List
Although the authors of the IPCP report on EDCs rejected the utility of the majority of the lists it unearthed, they were unable to dismiss outright every list based on the concerns outlined above.
Below, we highlight four chemical lists from the UNE-IPCP draft report that demand further scrutiny: The Endocrine Disruptor Exchange (TEDX) list; the SIN (Substitute It Now!) list from the International Chemical Secretariat (ChemSec); the Danish Environmental Protection Agency (Danish EPA) list; and the EU REACH SVHC list.
We selected three of these lists — the SIN List, Danish EPA List, and REACH SVHC List – in light of the fact that the draft UNE-IPCP report considered that they had the “most justified and robust selection criteria and have conducted rigorous assessment to review chemicals using referenced scientific evidence.”
The lists give the illusion of scientific certainty on the designation of the 45 substances as possible EDCs. Such designations exceed the current state of the science on EDCs and outpace regulatory review and decisions on those substances.
Although the draft UNE-IPCP report accorded greater credibility to these three lists and recommended further scrutiny of the 45 chemicals it referenced, significant problems remain with using the chemical lists:
- The lists give the illusion of scientific certainty on the designation of the 45 substances as possible EDCs. Such designations exceed the current state of the science on EDCs and outpace regulatory review and decisions on those substances.
- The organizations that created the lists do not appear to have had access to the full breadth of toxicological and epidemiological data that are needed to adequately assess the endocrine disrupting potential of the substances.
- In several cases, the organizations that created the three lists neither used the same approaches to evaluate data quality, nor used a systematic, weight-of-evidence analysis, which is the gold standard for evaluating a body of scientific evidence on a substance.
- The chemical lists mistakenly imply that each chemical listed was done so based on equally valid and robust science.
- The lists also mistakenly imply that each listed substance is an equally potent endocrine disruptor and poses equivalent risk of harm, when many of these substances can be used safely at current levels of exposure or by taking reasonable steps to minimize exposure.
We included the TEDX list because of the frequency with which it is cited by others and its potential influence on chemical purchasing decisions and consumers.
EU REACH SVHC LIST
The EU regulates industrial chemicals in commerce through a legislative act referred to as REACH (Registration, Evaluation and Authorization of Chemicals). At the request of the European Commission, a Member State or the European Chemicals Agency (ECHA) can propose a substance to be identified as a Substance of Very High Concern (SVHC). If identified, the substance is added to the Candidate List, which includes candidate substances for possible use restrictions and eventual phase-out.
As of this writing, there have been 168 chemicals nominated to the Candidate List, five of which were nominated based on their endocrine disrupting properties (Bis(2-ethyl)phthalate (DEHP), 4-(1,1,3,3-tetramethylbutyl)phenol, 4-(1,1,3,3-tetramethylbutyl)phenol ethoxylated, 4-Nonylphenol branched and linear, 4-Nonylphenol branched and linear ethoxylated).
SIN List of Suggested EDCs
The chemicals on the SIN List have been characterized by the private entity ChemSec as Substances of Very High Concern (SVHC) based on their interpretation of the criteria established by the EU chemicals regulation REACH. ChemSec claims to have developed their list in close collaboration with scientists and technical experts, as well as an NGO advisory committee of leading environmental, health, women and consumer organizations based mainly in Europe but also in the U.S.
The stated aim of the SIN List is to spark innovation towards products without particular targeted chemicals by accelerating the legislative processes and giving guidance to companies and other stakeholders on which chemicals to start substituting. A search done on October 6, 2016 of the SIN List yielded a total of 94 chemicals listed as suggested EDCs.
Danish EPA List of EDCs
The Danish Environmental Protection Agency in 2011 proposed a set of criteria for the European Commission to use to identify EDCs. In 2012, at the request of the Danish EPA, the Danish Centre for Endocrine Disruption conducted a study whereby it applied their proposed criteria to available evidence on 22 substances on the ChemSec SIN List 2.0. These substances had been identified by ChemSec as Substances of Very High Concern (SVHC) according to the criteria in REACH, solely due to their endocrine disrupting properties. A year later, without explaining why, the Centre expanded its evaluation with a second study of four fungicides.
The Danish Centre’s two studies identified 19 substances as “confirmed EDCs” and 10 substances as “suspected EDCs” using the proposed Danish criteria. Only 4 substances were identified as EDCs of very high regulatory concern when the Centre used the joint German-UK proposal which takes potency into consideration.
In 2016, the Danish EPA requested that the Centre reclassify 17 of the substances they had previously labeled as “confirmed EDCs” using only the WHO/IPCS definition of an EDC and ignoring the Danish EPA criteria. This resulted in only 10 of the 17 being classified as EDCs. In the judgment of the Centre, various limitations in the data for the remaining seven would make it difficult to achieve international agreement that they are EDCs.
In 2016, the Danish EPA also asked the Centre to identify an updated list of substances which meet the WHO/IPCS definition of an EDC from several thousands of substances included on various lists that have been compiled by authorities (i.e., the European Chemicals Agency and the Priority List of Chemicals from the European Commission) as well as by NGOs (ChemSec’s SIN list, TEDX, the Trade Union Priority List, and the 2012 WHO/UNE State of the Science report). After several rounds of prioritization of substances, they selected 13 for more thorough evaluation of the evidence and concluded that 9 fulfill the WHO/IPCS definition of an EDC, whereas 4 are suspected EDCs.
TEDX List of Potential EDCs
The Endocrine Disruption Exchange (TEDX) is a private entity dedicated to promoting the “endocrine issue” as a public health threat with policymakers, regulators, advocates and the public. TEDX does not use the WHO-IPCS definition of an EDC, which is widely accepted as the global standard; instead, TEDX assumes that, if a single peer-review study exists in the literature at any point in time that shows a chemical to have had any measurable interaction with the endocrine system, regardless of whether it causes an adverse health effect, the substance should be listed as a potential EDC. This assumption is completely inconsistent with weight-of-the evidence review and does not incorporate new evidence and the best available science.
To date, nearly 1,000 potential EDCs can be found on the TEDX List. This organization never “delists” a chemical even in the face of any new research findings which show a chemical is not an endocrine disruptor.