The first thing that you learn in a Toxicology 101 class is the old saying coined by the Renaissance German scientist Paracelsus that: “All things are poison, and nothing is without poison; only the dose permits something not to be poisonous.” We’ve shortened that to: ‘the dose makes the poison”. Anyway… a key question for public health is to figure out how much exposure (dose) to the thousands of chemicals that we’re exposed to every day is safe.
Figuring out how toxic chemicals are and whether or not they cause cancer is really important- because without that kind of key information the international public health system can’t develop targeted interventions or inform regulatory policy makers as they develop regulations to limit human exposure. So who does the research and who decides how toxic things are and what causes cancer?
A combination of forces do the work. Most of the primary research is done in Academia using various funding sources. Collections of researchers and experts evaluate published data to come up with consensus opinions. Internationally- the published work is evaluated by an arm of the World Health Organization International Agency for Research on Cancer (IARC). For example, this week IARC classified diesel engine exhaust as “carcinogenic to humans”.
In the US- it’s the EPA’s job to decide how toxic things are and what causes cancer. Probably the best source of information is the EPA’s Integrated Risk Information System, which compiles and presents the data that comes out of their external peer review procedures that assess toxicity and carcinogenicity. Using these data sources, policy makers can develop better informed regulations to limit human exposure and improve health outcomes. The Agency for Toxic Substances and Disease Registry ATSDR- which is associated with the CDC- is the public health arm that works with EPA to apply toxicity information to practical matters at polluted sites etc. I started my career at ADHS in 1992 working in our ATSDR grant funded program.