Optical detection of microplastics in water

Area of Science:

• Environmental Science
• Analytical Chemistry
• Optical Engineering

Background:

• Plastic pollution is a growing global threat, significantly endangering marine ecosystems.
• Microplastics in drinking water pose potential risks to human health, as highlighted by the World Health Organization (WHO).
• There is a critical need for accessible, portable, and cost-effective microplastic detection systems.

Purpose of the Study:

• To develop and present a prototype for a low-cost, portable microplastic detection system.
• To demonstrate the system's capability in identifying microplastics in water samples.
• To provide a cost-effective solution for widespread environmental monitoring.

Main Methods:

• The system is designed as a low-cost Raman spectrometer, integrating a 5 mW collimated laser, sample holder, notch filter, diffraction grating, and CCD sensor.
• All components are housed within a 3D-printed case, emphasizing portability and ease of use.
• The device's optical system is optimized for microplastic detection in aqueous samples.

Main Results:

• The prototype system successfully detected microplastics in water samples.
• The detection limit achieved was less than 0.015% w/v concentration of microplastics.
• The total cost of the prototype device is under $370, making it highly accessible.

Conclusions:

• The developed portable Raman spectrometer offers a viable and cost-effective method for microplastic detection in water.
• This technology has the potential for widespread global application in monitoring microplastic contamination.
• The device addresses the urgent need for easier and more affordable tools to combat plastic pollution.