LAUSR

Urban pollution is one of the main problems encountered worldwide with major impact on public health as well as the environment. Health impact of urban pollution is not limited to respiratory conditions but also encompasses major skin problems including irritation, skin ageing, and skin cancer. Toxic gases and particulate matter are the main pollutants and exhibit extensive local variability. The aforementioned pollutants are small particles that attach to the skin or penetrate into it, enhancing free radicals' production inside the inner skin layers. This urges the need to propose cosmetic products that help prevent and/or minimise pollutants' effects on the skin whether irritation, ageing and cancer. Furthermore, intrinsic and extrinsic factors contributed to skin irritation and ageing. Intrinsic factors are within skin factors and include genetic and physiological characteristics of individuals. Moreover, extrinsic factors comprise environmental factors such as humidity, temperature, and smoke. Subsequently active ingredients with antipollutant properties addressed the intrinsic and extrinsic factors by four mechanisms being: free radical neutralisation, film-forming ability, skin barrier enhancement and fortification. Such ingredients include vitamin A derivatives, vitamin C derivatives, carbohydrates, and plant-based products. Yet, very limited studies have evaluated the effectiveness of the aforementioned active ingredients against irritation or ageing and this should be considered in future work.