AOPs in chemical risk assessment - OECD webcast

Introduction to AOP framework, collaborative development, and application examples in chemical risk assessment. Speakers are Nathalie Delrue (OECD Secreteriat), Kate Willett (Humane Society International), Jason O’Brien (Environment Canada), Dan Villenueve (US EPA). Further information.

Send questions by 26 April to, to help determine the focus topics.

Chemical mixtures in food – EFSA guidance

People can be exposed to multiple chemicals from a variety of sources. Understanding how combined chemicals behave is complex and the number of combinations is potentially infinite. A new harmonised framework developed by the European Food Safety Authority EFSA will help scientists evaluate the potential ’combined effects’ of chemical mixtures in food and feed. Read the full story

7 New AOPs

The OECD Environment, Health and Safety Division requests review and endorsement of 7 Adverse Outcome Pathways (AOPs):

  • AOP 6: PPARα antagonism leading to body-weight loss
  • AOP 10: Blocking iGABA receptor ion channel leading to seizures
  • AOP 21: AhR mediated mortality
  • AOP 42: TPO Inhibition and Altered Neurodevelopment
  • AOP 54: NIS inhibition and learning and memory impairment
  • AOP 131: AhR activation-uroporphyria
  • AOP 150: AhR activation to ELS mortality, via VEGF

Deadline for comments is 29 March 2019. See further details.

EU-ToxRisk Update

EU-ToxRisk is a Horizon2020-funded European ‘Flagship’ Programme driving mechanism-based toxicity testing and risk assessment for the 21st century. The ultimate goal is to deliver testing strategies for reliable, animal-free hazard and risk assessment of chemicals. The latest newsletter can be found here.

EFSA lowers safe level for toxic dioxins in food by a factor of seven

The EFSA expert panel on contaminants in the food chain (CONTAM) set a new tolerable weekly intake (TWI) for dioxins in food of 2 picograms per kilogram of body weight, based on new epidemiological and animal data and more refined modelling approaches for predicting dioxin levels in the human body. See reference.

SCAHT on Twitter

You can now follow @SCAHTorg on Twitter.

SCAHT office

The SCAHT office will be closed from 22nd December 2018 until 1st January 2019.

Christmas Greetings

Dear partners and friends of SCAHT,

As the year ends, we have already completed the first half of our current financial period. Thanks to your support, we have had a successful year across all our activities, in research, in supporting the authorities, and in our training programmes.  

We would like to thank you for your valuable contributions this year and wish you and your family a very merry Christmas and a happy New Year.

                           Your SCAHT team

SCAHT AOP on developmental neurotoxicity and neurodegeneration

A newly published Adverse Outcome Pathway (AOP) from the SCAHT network (Florianne Tschudi-Monnet and Rex FitzGerald) links chemical effects during brain development (chronic NMDA receptor inhibition) to impairment of learning and memory and Alzheimer-like neurodegeneration. Such AOPs will be important for both researchers and regulators. Further information.

New publication on quantitative risk assessment model for evaluating the safety of skin sensitizing plant protection products

Fruit of a collaboration between Federal Authorities and SCAHT researchers, this paper discusses a novel approach for quantitative risk assessment of the skin sensitizing potential of plant protection products. The proposed methodology combines the derivation of substance-specific thresholds (so-called Derived No-Effect Level, DNEL) for skin sensitizers and an agricultural exposure model used for assessing chronic health risks of plant protection products in an occupational context. In particular, the approach aims to more fully account for both potency and frequency of exposure in addition to the dose applied, which is to date the main regulatory decision criterion considered when evaluating skin sensitizers safety.