Home and Top Tools

Improving toxicological hazard assessment

- A collection of links to useful tools 

Owned and maintained by Niels Hadrup, Toxicologist (ERT)

Location: Copenhagen, Denmark and Trondheim, Norway

This site describes R2P (research to practice) on the toxicology of spray-formulated chemicals (see the links above), and collects useful links for doing toxicological hazard assessment


Some quick links (for my top 6 tools) are here - Other tools can be found in the menus above


Danish QSAR Database:https://qsar.food.dtu.dk/

An excellent tool for getting an overview of the potential toxicity of organic substances




ECHA R8 guideline - the guideline used to make health-based recommendations for exposure limits by the National Research Centre for the Working Environment in Denmark 




WHO's IARC database




CLP / EU harmonised classifications (Annex VI




The Danish Work Authorities list of occupational exposure limits (Arbejdstilsynets

grænseværdiliste):




Calculation of ppm to mg/m3 in inhalation studies

It is highly useful to be able to do this quickly as most old tox papers give ppm - and usually you want the exposure dose to be in mg/m3


XXX mg/m3 = YYY ppm x Molecular weight / 24.45


Or use the calulator located at:





Review articles where you can find dose descriptors for you risk assessment - here is a link to our papers that are almost like a ready-meal from the supermarket - ready to use!






EFSA default values

You need to use these values when calculating oral doses in mg/kg bw (body weight) from feed or drinking water concentrations  




I hope the site is useful /Niels Hadrup



The dose makes the poison (Paracelsus)