Microplastic Exposure: Time-Dependent Effects on Oxidative Stress, Apoptosis, and Cellular Internalization in...

Area of Science:

• Environmental Science
• Toxicology
• Cell Biology

Background:

• Microplastics (MPs) are pervasive environmental contaminants with largely unknown effects on human health.
• Polyethylene terephthalate (PET) is a common plastic raising public health concerns, particularly regarding its impact on skin.
• The toxicological profile of PET MPs in skin cells requires thorough investigation.

Purpose of the Study:

• To evaluate the toxicological effects of PET MPs on fibroblast cells.
• To assess the impact of exposure duration (24h vs. 48h) on PET MP toxicity.
• To investigate cellular responses including oxidative damage, lipid accumulation, apoptosis, and cellular interaction.

Main Methods:

• Fibroblast cell cultures exposed to varying concentrations of PET MPs.
• Cell viability assessed using water-soluble tetrazolium salt (WST-1) and lactate dehydrogenase (LDH) assays.
• Oxidative stress markers (ROS, MDA), lipid accumulation, apoptosis/necrosis rates, and cellular internalization were measured.

Main Results:

• PET MPs exhibited cytotoxic effects, with significantly higher toxicity observed at 48-hour exposure compared to 24-hour.
• Cell viability decreased in a dose- and time-dependent manner.
• Apoptosis and necrosis rates increased significantly after 48-hour exposure, alongside elevated ROS, MDA levels, and lipid droplet accumulation.
• Time-dependent internalization of PET MPs into fibroblast cells was confirmed.

Conclusions:

• PET microplastics pose potential health risks to skin cells.
• Exposure duration is a critical factor influencing PET MP toxicity.
• Further toxicological evaluations are essential, especially for longer exposure times, before widespread biomedical or environmental application.