Substance and Toxicity databases
From London Hackspace Wiki
If you find some chemical in a test tube and you don't know what it is. Then here are a good list of places to check the effects and considerations online.
Toxic substances lists
Agency for Toxic Substances & Diseases Registry http://www.atsdr.cdc.gov/substances/index.asp
Toxic substances portal
Access the most important information about toxic substances and how they affect our health
http://www.atsdr.cdc.gov/toxguides/index.asp
ToxGuides http://www.atsdr.cdc.gov/toxguides/index.asp
Food Safety
list of Food Safety Hazards Guidebook
Drugs and Medicine
US Food and Drug Administration http://www.accessdata.fda.gov/scripts/cder/drugsatfda/index.cfm
Drugbank is a searchable bioinformatics and chemoinformatics resource http://www.drugbank.ca/
Chemicals and substances
ChemSpider http://www.chemspider.com/
