Global MnP Observation Strategy

TL;DR

                  +---------------------------------+
                  |     Global MnP Observation      |
                  +----------------+----------------+
                                   |
                +------------------+------------------+
                |                                     |
   +--------------------------+         +---------------------------+
   |  A. Measurement Studies  |         |  B. Modelling Studies     |
   +------------+-------------+         +-------------+-------------+
                |                                     |
  +-------------+---------------+    +----------------+-----------------+
  | 1. Monitoring (Long-term)   |    | 1. Transport Modelling           |
  | - GAW stations              |    | - Air/ocean Movement Pathways    |
  | - Passive & active samplers |    +----------------------------------+
  | - Weekly/monthly samples    |    | 2. Source Modelling              |
  +-----------------------------+    | - Emission identification        |
  | 2. Exploration (Spatial)    |    +----------------------------------+
  | - Research vessels          |    | 3. Flux Modelling                |
  | - UAVs & aircraft           |    | - Emission → Transport → Deposit |
  | - Remote/offshore sampling  |    | - Policy Impact Simulation       |
  +-----------------------------+    +----------------------------------+
  | 3. Process Studies          |
  | - Emission/resuspension     |
  | - Ocean–air interface       |
  | - Deposition mechanisms     |
  | - Mass/particle count link  |
  +-----------------------------+

Overview

Objectives:

• Quantify emission, transport, deposition, and re-emission of MnP in the marine atmosphere.

• Integrate the atmospheric pathway into the global plastic pollution cycle.

• Reduce the wide uncertainty in MnP flux estimates (currently ranging from 0.013–25 Mt/year).

• Generate reliable, policy-relevant data for regulation, environmental management, and health risk assessments.

Analytical Methods:

Size Range	Method	Purpose
>10 µm	µFTIR, µRaman	Standard polymer identification
<1 µm (NP)	AFM-IR, Raman tweezers	High-resolution nanoplastic detection
All sizes	Py-GC-MS, TD-GC-MS	Mass-based quantification
Cross-method	N.A.	Bridge count and mass for comparability

Infrastructure for Reliable Monitoring

• Standardization & Quality Assurance (QA/QC)

  • Report limits of detection (LOD) and quantification (LOQ).

  • Use fine particle size bins (e.g., \(5 \mu m\)) for better resolution.

  • Include replicates, field/lab blanks, and contamination controls.

  • Ensure 10–30% of detected particles are chemically validated (e.g., spectroscopy or thermal degradation).

  • Distinguish between aerodynamic diameter (for transport/inhalation) and physical size (for ecological impact).

  • Promote harmonized sampling and analysis protocols across studies and regions.

• Global Observation Network

• Core Network: Leverage existing stations (e.g., WMO/GAW and EMEP) at sites like Mace Head, Cape Grim, and Mauna Loa.

• Geographic Expansion:

  • Add coverage in under-sampled regions (Africa, South Asia, Pacific, Southern Oceans).

  • Deploy offshore and mobile platforms in open ocean areas.

• Sampling Platforms

  • Active samplers: High-volume air filters (e.g., Tisch HiVol).

  • Passive collectors: Devices like NILU or Petri dishes for deposition.

  • Marine samplers:

    • BIMS for sea spray and bubble-burst particle ejection.

    • MWAC for larger airborne particles.

  • Aerial samplers: UAVs for near-surface and vertical air column measurements.

• Feedback Loop (once enough long-term data is collected)

  • Identify regional hot spots, dominant transport pathways, and temporal trends.

  • Evaluate mitigation policy effectiveness.

  • Prioritize pollution source interventions (e.g., tire wear, textile fibers, marine industry).

  • Refine climate and health risk assessments using real exposure data.

Back to Micro-nanoplastics.