Binational survey of personal protective equipment (PPE) pollution driven by the COVID-19 pandemic in coastal environments: Abundance, distribution, and analytical characterization

Abstract

In the present contribution, two nationwide surveys of personal protective equipment (PPE) pollution were conducted in Peru and Argentina aiming to provide valuable information regarding the abundance and distribution of PPE in coastal sites. Additionally, PPE items were recovered from the environment and analyzed by Fourier transformed infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM) with Energy dispersive X-ray (EDX), and X-ray diffraction (XRD), and compared to brand-new PPE in order to investigate the chemical and structural degradation of PPE in the environment. PPE density (PPE m^-2) found in both countries were comparable to previous studies. FTIR analysis revealed multiple polymer types comprising common PPE, mainly polypropylene, polyamide, polyethylene terephthalate, and polyester. SEM micrographs showed clear weathering signs, such as cracks, cavities, and rough surfaces in face masks and gloves. EDX elemental mapping revealed the presence of elemental additives, such as Ca in gloves and face masks and AgNPs as an antimicrobial agent. Other metals found on the surface of PPE were Mo, P, Ti, and Zn. XRD patterns displayed a notorious decrease in the crystallinity of polypropylene face masks, which could alter its interaction with external contaminants and stability. The next steps in this line of research were discussed.

Keywords: Marine; Mask; Microplastic; Plastic; SARS-CoV-2.

Graphical abstract

Fig. 1

(a) Boxplot displaying individual PPE densities across sampling sites in Peru and Argentina. (b) Pie charts displaying the contribution of different types of PPE items in Peru (top) and Argentina (bottom).

Fig. 2

Map of Peru (a) and Argentina (b) displaying the spatial distribution and level of PPE pollution (PPE m⁻²) across sampling sites.

Fig. 3

Scatter plot diagrams and linear regression of the predictor and response variables in the datasets of Peru. P-values were determined by the Spearman correlation test.

Fig. 4

Scatter plot diagrams and linear regression of the predictor and response variables in the datasets of Argentina. P-values were determined by the Spearman correlation test.

Fig. 5

Box plot and individual values of PPE density grouped per coastal activity in Peru. ns: No significant differences (Kruskal-Wallis test). T/R: Tourism or recreational. NR: Natural reserve.

Fig. 6

Photographs of a white surgical face mask (top) and cloth mask (bottom) and their corresponding FTIR spectrum (outer face mask layer).

Fig. 7

(a) Photograph of white surgical face mask. a1. zoomed face mask image and its spectrum. a2. elastic cord spectrum. (b) Photograph glove and their corresponding ATR-FTIR spectrum and (c) photograph of the NPs-face mask. c1 ATR-FTIR spectrum from the inner layer of the NPs-face mask, and c2 ATR-FTIR spectrum from the elastic cord. Zoomed image of the inner layer of NPs-face mask image (small insert).

Fig. 8

(a-aII) SEM micrographs, EDX punctual spectra of PP-face mask pattern, and SEM-EDX elemental mapping of the weave of the layer of the PP-face mask pattern. (b-bI) SEM micrographs and SEM-EDX elemental mapping of the weave of the PP-face mask sample.

Fig. 9

(a-aI) SEM micrographs and EDX punctual spectra of NPs-face mask pattern, and (b-bI) SEM micrographs and SEM-EDX elemental mapping of NPs-face mask sample.

Fig. 10

(a) SEM micrographs and (b) EDX punctual spectra of gloves found in coastal areas.

Fig. 11

The X-ray diffraction (XRD) spectra of (a) PP-face mask pattern and the PP-face mask sample, and (b) NPs-face masks pattern and NPs-face masks found during sampling in coastal areas.