J. Nanopart. Res. 14, 878 (2012)

Two types of nanoparticles can enter the environment: unintentionally produced incidental nanoparticles from pollution or combustion products, and intentionally produced engineered nanomaterials such as carbon nanotubes. Epidemiological studies have shown a link between the number of ambient ultrafine particles and respiratory illnesses. Moreover, several cell culture and animal studies have shown that when inhaled, engineered particles with diameters of less than 100 nm can enter the lungs, circulate in the blood and cause harmful effects such as inflammation, cancer and heart problems. Now, researchers in Taiwan have shown that few adverse health effects are detected in factory workers who handle engineered nanoparticles.

Saou-Hsing Liou of the Division of Environmental Health and Occupational Medicine at the National Health Research Institute in Taiwan and co-workers from various institutes in Taiwan used a questionnaire to collect data on exposure status and demographics, and measured the urine and blood samples of the factory workers for biomarkers that could indicate health effects. Fourteen factories with a total of 227 exposed workers and 137 unexposed workers participated, and the risk level of each worker was categorized according to the nanotool risk-level matrix, where risk level is scored based on the severity of the toxicity of the nanomaterial and the probability of exposure. Exposed workers had lower levels of antioxidant enzymes and increased cardiovascular markers than unexposed workers. However, no differences were seen in lung function or markers for lung inflammation, oxidative stress or genotoxicity amongst all workers, suggesting little adverse response.