Endocrine Disruption
Our work
The human endocrine system is a complex and interlinked series of organs and glands producing hormones critical for normal growth and development, metabolic homeostasis and reproduction. Endocrine-active chemicals that have the ability to disrupt this intricate and well-balanced system, or endocrine disruptors (EDs), are of significant toxicological, and current regulatory, concern.
Current focus is on those compounds that disrupt the Estrogenic, Androgenic, Thyroid and/or Steroidogenesis (EATS) axes. Comprehensive guidance on testing frameworks for endocrine disrupting chemicals acting on these axes have been published by the OECD and by ECHA/EFSA, with the joint ECHA/EFSA guidance also providing strategies for gathering evidence on, and evaluation and interpretation of the endocrine disruption hazard.
Our toxicologists are skilled in the use of high-throughput screening tools, such as the US EPA’s ToxCast, and in the evaluation and interpretation of in silico and in vitro New Approach Methodologies (NAMs) as well as extracting relevant data from existing laboratory animal and epidemiological studies.
Every day exposures to Endocrine Disrupting Chemicals
How people are exposed
- Children's toys (phthalates)
- Plastic drinking bottles (BPA, BPS, BPF)
- Cleaning products (phthalates, triclosan)
- House dust (flame retardants, pesticides)
- Home furniture (flame retardants, PFAS)
- Building materials (flame retardants, phthalates, PFAS)
- Fragrances (phthalates)
- Food (pesticides such as chlorpyrifos)
- Food packaging (BPA, PFAS, phthalates)
- Thermal cash register receipts (BPA, BPS)
- Drinking water (arsenic, lead, perchlorate)
- Personal care products (parabens, phthalates, triclosan)
ED Assessment under BPR and PPPR
Bibra toxicologists have extensive experience of evaluating the ED properties of active substances and non-active co-formulants under the Biocidal Products Regulations (BPR) (EU 2017/2100) and active substances under the Plant Protection Products Regulations (PPPR) (EU 2018/605). We work within the ECHA/EFSA guidance, utilising our long-established expertise in conducting comprehensive literature searches, selecting relevant studies, and judging their scientific adequacy and quality. We enter relevant data into the Appendix E1 Excel template and critically assess the resultant “Lines of evidence” for adversity and endocrine activity.
ED Assessment under EU CLP and REACH
On 31 March 2023, the European Commission adopted the Commission delegated regulation (EU) 2023/707 which added new Endocrine Disruption hazard classes to Regulation (EC) No 1272/2008 on the classification, labelling and packaging (CLP) of substances and mixtures. As such, in regard to human health and/or the environment, known or presumed EDCs must be classified as Category 1 and suspected EDCs as Category 2. Our toxicologists can evaluate existing REACH registration dossier study summaries for ED-relevant endpoints and, as part of a Weight-of-Evidence (WoE) assessment, advise on the need for additional testing.
ED Assessment in other areas
Evaluation of Endocrine Disruption potential forms a key part of our human health risk assessments for extractables and leachables. We have also conducted bespoke Endocrine Disrupting Chemical assessments for the food and food contact industries, and for consumer products.
Some of our Endocrine Disruption case studies
NAMs for NGRAs
Blog articles
Traditionally, toxicological risk assessment has involved identifying a point of departure (PoD) such as a NOAEL or LOAEL in a study of small creatures, adjusting it to be relevant to humans (to derive, for example, a TI or DNEL), and then calculating the margin of safety to a measured or estimated external exposure. As part of this process, toxicologists have to account for the uncertainties that arise in moving from the species, route and duration of the laboratory animal study to the real human world.
FDA memoranda: genotoxicity and carcinogenicity assessments of ENDS
Blog articles
As discussed in a previous blog post, the U.S. Food and Drug Administration (FDA) Center for Tobacco Products (CTP) has issued several “scientific policy memoranda” that provide some great insights into the Agency’s evaluation process. In June 2024, the FDA made two new memos available that relate to the genotoxicity and carcinogenicity assessment of chemical constituents of Electronic Nicotine Delivery Systems (ENDS).
FDA memoranda: shedding light on health risk assessment of ENDS in PMTA submissions
Blog articles
In 2016, the United States (US) Food and Drug Administration (FDA) ruled that Electronic Nicotine Delivery Systems (ENDS) were to be regulated just like more traditional tobacco products, meaning that ENDS (e-cigarettes and e-liquids) are subject to premarket review requirements, despite containing no tobacco. ENDS manufacturers must therefore submit a Premarket Tobacco Product Application (PMTA) to the FDA Center for Tobacco Products (CTP) in order to have any chance of legally marketing their products in the US.
