A federal public health agency of the U.S. Department of Health and Human Services. Provides "toxicological profiles" for hundreds of toxic substances.
The Toxic Substances Portal https://www.atsdr.cdc.gov/substances/index.asp gives quick access to toxicological resources by health effect and chemical class.
Data, tools, and resources to conduct research, develop web and mobile applications, and design data visualizations. Includes data on climate, education, energy, health, science, and more.+
Data from the 193 World Health Organization (WHO) member states. Download sections in pdf. For more detail on any specific country, consult the Global Health Observatory (GHO).