Chemistry

Ecology

Materials science

Particulates

Toxicity

Human health

Aerodynamic diameter

Pollution

Particle (ecology)

Air pollutants

Environmental health

Pollutant

Nanotechnology

Organic chemistry

Biology

Ultrafine particle

Environmental chemistry

Air pollution

Environmental science

Medicine

Environmental engineering

Geoscience Frontiers

Air pollution by particulate matter (PM) is one of the main threats to human health, particularly in large cities where pollution levels are continually exceeded. According to their source of emission, geography, and local meteorology, the pollutant particles vary in size and composition. These particles are conditioned to the aerodynamic diameter and thus classified as coarse (2.5–10 μm), fine (0.1–2.5 μm), and ultrafine (<0.1 μm), where the degree of toxicity becomes greater for smaller particles. These particles can get into the lungs and translocate into vital organs due to their size, causing significant human health consequences. Besides, PM pollutants have been linked to respiratory conditions, genotoxic, mutagenic, and carcinogenic activity in human beings. This paper presents an overview of emission sources, physicochemical characteristics, collection and measurement methodologies, toxicity, and existing control mechanisms for ultrafine particles (UFPs) in the last fifteen years.

Sources, characteristics, toxicity, and control of ultrafine particles: An overview