Unveiling the toxicity of micro-nanoplastics: A systematic exploration of understanding environmental and health implications

Abstract

The surge in plastic production has spurred a global crisis as plastic pollution intensifies, with microplastics and nanoplastics emerging as notable environmental threats. Due to their miniature size, these particles are ubiquitous across ecosystems and pose severe hazards as they are ingested and bioaccumulate within organisms. Although global plastic production has reached an alarming 400.3 MTs, recycling efforts remain limited, with only 18.5 MTs being recycled. Currently, out of the total plastic waste, 49.6 % is converted into energy, 27 % is recycled, and 23.5 % is recovered as material, indicating a need for better waste management practices to combat the escalating pollution levels. Research studies on micro-nanoplastics have primarily concentrated on their environmental presence and laboratory-based toxicity studies. This review critically examines the sources and detection methods for micro-nanoplastics, emphasising their toxicological effects and ecological impacts. Organisms like zebrafish and rats serve as key models for studying these particle's bioaccumulative potential, showcasing adverse effects that extend to DNA damage, oxidative stress, and cellular apoptosis. Studies reveal that micro-nanoplastics can permeate biological barriers, including the blood-brain barrier, neurological imbalance, cardiac, respiratory, and dermatological disorders. These health risks, particularly relevant for humans, underscore the urgency for broader, real-world studies beyond controlled laboratory conditions. Additionally, the review discusses innovative energy-harvesting technologies as sustainable alternatives for plastic waste utilisation, particularly valuable for energy-deficient regions. These strategies aim to simultaneously address energy demands and mitigate plastic waste. This approach aligns with global sustainability goals, providing a promising avenue for both pollution reduction and energy generation. The review calls for further research to enhance detection techniques, assess long-term environmental impacts, and explore sustainable solutions that integrate energy recovery with pollution mitigation, especially in regions most affected by both energy shortages and increased plastic waste.

Keywords: Environmental pollution; Humans; Micro-nanoplastics; Rats; Toxicity; Zebrafish.

Graphical abstract

Fig. 1

(a) A Geographic View of Plastic Pollution: Mapping Production and Waste by Region, (b) Distribution of global plastics production by polymer type, (c) Origins of Micro and Nanoplastics Pollution.

Fig. 2

(a) Uptake and accumulation of micro-nanoplastics in adult zebrafish, larvae, and embryos. (b) PS-NPs distribution in the chorionic membrane or in vivo of F1 embryos/larvae (8–120 hpf) post exposure to various particle sizes of PS-NPs (Reproduced with permission from Zhou et al. , Elsevier).

Fig. 3

(a) Illustrates micro-nanoplastics uptake and accumulation in rats. (b) Shows effects of PS-NPs and Cd exposure, highlighting: (A) Heart pathologies, (B) body weight changes, (C) heart weight, (D) heart coefficients (%), (E) Ultrastructural findings: broken myofilaments, swollen mitochondria, (F) H&E staining, (G) Masson's trichrome staining, (H-I) Western blot analysis for CTnT protein levels, and (I) Proportion of fibrosis area (%). (Reproduced with permission from Ye et al. [85]).

Fig. 4

Sources and Accumulation of micro-nanoplastics in Human.

Fig. 5

(a) Arterial sample microplastic concentration and (b) Estimation of total microplastic loads in human bodies using current and online data. Tissues used for total microplastic abundance estimation include lungs, spleen, kidney, small intestine, large intestine, and liver; tissues for microplastic mass estimation include lungs, small intestine, large intestine, and blood (Reproduced with permission from Zhu et al. respectively).