Much epidemiological data on the effects of environmental pollution and nanomaterials manufactured in large quantities (carbon black, titanium dioxide, silica fume, for example) are available. But, nanomaterial data don’t allow any conclusions.For more sophisticated nanomaterials (recent sector), knowledge of the toxicity will come as a first step from experimental toxicology.

Numerous epidemiological studies on environmental pollution have highlighted health effects (notably respiratory and cardiac) on already fragile people. These studies provide arguments for the role of fine and ultra-fine particles, but must be interpreted cautiously considering factors of confusion: associated chemical pollution, etc.

In industries that manufactured nanomaterials "in mass" for several decades with tens of thousands of employees, several epidemiological studies have been carried out. The short term health effects (for example, respiratory diseases) have been observed, but pathologies of cancerous type have not been clearly identified. In august 2009, in a Chinese production workshop, there was the first suspicion of implication of “nano” in a professional accident. But, no evidence for a causal relation was found between nanoparticles and serious pleuropulmonar effects observed with rugged women.