Nanomaterial toxicity, hazards, and safety

Abstract

Manufactured nanoparticles of different chemical compositions are now widely commercially applied. They are found in places as diverse as food packaging and automotive bumpers, where their special nanoscale properties help to lower cost while improving performance. Given these widespread applications, the unintended effects of manufactured nanomaterials on workers, consumers, and the environment have become a focal point for international research. Initially, the human health effects of nanoscale materials were of most interest, but more recently identification of nanoscale particles in wastewater sludge has turned attention towards their environmental impacts. Though the topic of nanomaterial safety has received substantial attention in the literature, many basic questions about nanoparticle transport, fate, and toxicology remain unanswered. A central challenge for researchers has been the definitive characterization of particular manufactured nanomaterials, particularly in commercial products that have significant human or environmental exposure. Careful determination of the physical size, surface chemistry, internal structure, and intermediate stability of manufactured nanomaterials helps investigators compare results, as well as link unwanted biological outcomes to particular material features. This chapter provides an overview of the current exposure and toxicity studies of manufactured (e.g., engineered) nanomaterials. A special emphasis in this chapter is the practice used for nanomaterial characterization as it relates to their biological and environmental properties.