Improvements in evidence
appraisal, but not in
burden of proof
As the debate about how to identify of endocrine disruptors for regulation in the EU comes to a head, the EU Commission has published another draft of its proposed criteria for identification of EDCs. These will be discussed and potentially voted on by Member States on 21 December.
The previous draft was criticised in an open letter by a group of scientists for proposing a confused set of processes for assessing evidence of endocrine disrupting potential, and for setting too high a bar for classifying problematic chemicals as EDCs.
While the new draft resolves (at least on a generous reading) most of the technical issues identified in the letter (see points 1, 3 and 4 in the letter), the more contentious and political issues remain untouched (points 2 and 5).
Improvements in the draft:
- On a perhaps over-generous reading, the two-tier approach to evidence appears to have been eliminated: the criteria now seem to aim at ensuring that, in addition to data produced using standardised protocols, all relevant non-protocol data is systematically identified and assessed (see paras 2a and 2b). The suggestion that assessment of non-protocol data should happen in parallel or through a secondary process appears to no longer be present.
- The wording around how to apply the weight of evidence assessment is less muddled: there is now a relatively simple list of six things which need to be accounted for which seems comprehensive and flexible enough to allow SR methods, without being overly prescriptive about what the methods should be.
- The ambiguous language around “may cause adverse effects” appears to have been cleared up.
- There still needs to be introduction of categories of endocrine disruptor that reflect the strength of the available evidence. (Note that the French authorities are insisting that EDCs should be identified according to three distinct categories: known; presumed; and suspected.)
- There is still too high a burden of proof on identifying EDCs. Paragraph 1b of the new draft should simply read “alters the function of the endocrine system” (it being unclear what work the term “mode of action” is doing here), while paragraph 1c should read something like “the adverse effect is plausibly a consequence of altered function of the endocrine system”.
- The new draft has retained the wording which changes the regulation from being a hazard-based approach to a risk-based approach, i.e. “negligible exposure” to “negligible risk”.
Other groups have raised additional criticisms, including registering surprise at some new criteria relating to identification of EDCs as they affect wildlife populations.
Overall, in spite of the resolution of some important technical issues, it would appear there is still a long way to go before the criteria address the major points of controversy in identifying chemicals for regulation as endocrine disruptors.
December 2016 News Bulletin: Fire retardants – health hazard or life saver? Plus identifying environmental factors in breast cancerDecember 15, 2016 at 5:41 pm | Posted in News and Science Bulletins | Leave a comment
December 2016 News Bulletin
Fire retardant chemicals: health hazard or a life saver? Former civil servant and fire regulations expert Terry Edge says it’s time people in the UK were told just what chemicals are in our furniture and given the option to buy non-FR products if we want. (DecoMag) See also: UK to be challenged over furniture fire safety rules (ENDS Report)
Institutes in the Lead: Identifying Environmental Factors in Breast Cancer. In a way, it all started in Long Island, New York. The year was 1993. An apparent cluster of breast cancer cases had been discovered in Nassau and Suffolk counties, and some residents worried that pesticide applications on former farmland could be to blame. They demanded an investigation. The U.S. Congress soon agreed and asked the National Institute of Environmental Health Sciences (NIEHS) and the National Cancer Institute (NCI) to research the potential role of environmental exposures in these cases. In the decades since, these institutes have conducted and funded countless studies on potential environmental risk factors for breast cancer. (EHP)
The paradoxes of investigating potential harms from chemical substances – Professor Åke Bergman, Swetox. Firstly, governments, other research and monitoring bodies have spent enormous amounts of money, hiring professionals to search for environmental contaminants and detect and report on chemicals already known by the manufacturers. Secondly, resources that could have been invested in the safety of chemicals, through toxicological and ecotoxicological testing, have been used to search for unknown chemicals. How long will the EU and national governments accept this? (Chemical Watch)
“Let’s stop the manipulation of science.” Around a hundred scientists ask Europe and the international community to act against endocrine disrupting chemicals. They condemn the use of strategies for manufacturing doubt employed by industries in the climate change battle. (Le Monde)
EU court backs disclosure of pesticides information. The Court of Justice has made a ruling in response to two court cases questioning whether pesticides are covered under the Aarhus Convention. (ENDS Report)
December 2016 Science Bulletin: EDCs affect fetal development, may raise obesity risk; more detail on the “DOHaD Hypothesis”December 15, 2016 at 4:31 pm | Posted in News and Science Bulletins | Leave a comment
December 2016 Science Bulletin
EDCs, fetal development | Occupational Exposure to Endocrine-Disrupting Chemicals and Birth Weight and Length of Gestation: A European Meta-Analysis. Eleven percent of pregnant women were classified as exposed to EDCs at work during pregnancy, based on job title. Classification of exposure to one or more EDC group was associated with an increased risk of term LBW [odds ratio (OR) = 1.25; 95% CI: 1.04, 1.49], as were most specific EDC groups; this association was consistent across cohorts. Further, the risk increased with increasing number of EDC groups (OR = 2.11; 95% CI: 1.10, 4.06 for exposure to four or more EDC groups). There were few associations (p < 0.05) with the other outcomes; women holding job titles classified as exposed to bisphenol A or brominated flame retardants were at higher risk for longer length of gestation.
EDCs, obesity, neurodevelopment | Early-life exposure to EDCs: role in childhood obesity and neurodevelopment. The available epidemiological evidence suggest that prenatal exposure to several of these ubiquitous EDCs is associated with adverse neurobehaviour (BPA and phthalates) and excess adiposity or increased risk of obesity and/or overweight (PFAS). Quantifying the effects of EDC mixtures, improving EDC exposure assessment, reducing bias from confounding, identifying periods of heightened vulnerability and elucidating the presence and nature of sexually dimorphic EDC effects would enable stronger inferences to be made from epidemiological studies than currently possible.
Air pollution, asthma | Exposure to traffic-related air pollution and risk of development of childhood asthma: A systematic review and meta-analysis. The overall risk estimates from the meta-analyses showed statistically significant associations for BC, NO2, PM2.5, PM10 exposures and risk of asthma development. Our findings support the hypothesis that childhood exposure to TRAP contributes to their development of asthma. Future meta-analyses would benefit from greater standardization of study methods including exposure assessment harmonization, outcome harmonization, confounders’ harmonization and the inclusion of all important confounders in individual studies.
DOHaD Hypothesis | Review of developmental origins of health and disease publications in environmental epidemiology. We conducted a scoping literature review to describe the human evidence for the DOHaD hypothesis and to identify, 1) where there may be reasonable data to draw conclusions, and 2) areas warranting further research. Using PubMed and Web of Science we identified 425 publications through 2014 that met our criteria for evaluating the DOHaD hypothesis in environmental epidemiology. These publications covered 60 different chemicals. The majority of publications focused on neurological/cognitive outcomes, followed by cancer, and respiratory outcomes.
BPA, obesity, diabetes | Urinary bisphenol A is associated with insulin resistance and obesity in reproductive-aged women. Urinary BPA levels were positively correlated with BMI, waist circumference, fasting serum insulin and HOMA-IR. MEHHP, MEOHP and MnBP were not associated with any of the above parameters. In the multiple regression analysis, the BPA levels were significantly associated with BMI and waist circumference after adjusting for age, smoking and alcohol consumption status, triglycerides (TG), total cholesterol (TC) and high-density lipoprotein (HDL). Fasting insulin and HOMA-IR values were also significantly related to urinary BPA concentration after adjusting for confounding variables. Metabolically unhealthy women exhibited significantly higher levels of urinary BPA (P = 0·01) compared to metabolically healthy women.