Microplastics in Animals – A Global Concern to Food Safety and Human Health

Abstract

Throughout history, animals have been a vital source of protein and energy and have been utilized in agriculture to produce food for human consumption. The increasing global demands for protein are being met through the increased production of meat, milk, eggs, and other food items, and is facilitated by the rapid pace of industrialization. However, the increase in food production and new technologies has led to the release of novel environmental pollutants, including microplastics (MPs). Currently, MPs are found in diverse ecosystems, exerting adverse effects in both terrestrial and aquatic organisms. While scientific evidence supports that MPs can harm aquatic organisms, recent studies have also begun to investigate the effects of MPs on terrestrial ecosystems, marking a significant shift from the traditional focus on aquatic environments. This chapter aims to synthesize current knowledge on the occurrence and distribution of MPs in food and their presence in aquatic and terrestrial animals, in addition to discussing the potential consequences for human health. Evidence supports that plastic mulching and compost are prominent sources of MPs in agricultural fields, whereas irrigation channels act as vital sources of MP contamination in aquaculture systems. A high abundance of MPs has been found in soil-dwelling worms, livestock, companion animals, and wild animals. In Africa, the north Tunisian lagoons of Bizerte, Ghar El Mehl and Lake Victoria are prominent areas of MP contamination. In Asia, China contributes the highest abundance of MPs to the environment. Exposure to MPs cause oxidative stress, immunotoxicity, neurotoxicity, reproductive impairment, and endocrine disruption in both terrestrial and aquatic animals. Current evidence suggests the need for further investigation into the specific sources of MP exposure in animals and the routes through which it enters the human body. Legislators need to implement programs and collective actions to modify public behaviour and reduce MPs pollution in the natural environment.