Table 2.
Recent studies on littered PPE in metropolitan locations worldwide.
| Study location | Environment | Area surveyed (m2) and number of days | Sampling location | Methods | Key findings | Reference |
|---|---|---|---|---|---|---|
| Kenya | City | NR; 30 | Streets | 1) A distance between 200 m and 2000 m was surveyed 2) PPE litter was picked from a width of 2 m on both sides of the street |
1) 0–5.6 × 10−2 PPE m−2 | Okuku et al., 2021 |
| South Africa | Urban | NR; 50 | Streets | 1) Litter was collected from 400 m of street margins | 1) Face masks and gloves contributed <1% of total mass 2) Found wet wipes amid other PPE |
Ryan et al., 2020 |
| Ghana | City | NR | Streets | 1) Survey by transects covering a distance of 100 m to 200 m of different areas like township, suburb, institution, municipal and community 2) Visually identified, counted and photographed |
1) Total of 535 face masks along 1720 m stretch 2) Density range 0.04 m to 0.42 m |
Amuah et al., 2021 |
| Canada | City | 245,190; 34 | Street, under cars, residential areas, grocery, and hospital zones | 1) Collected debris that was 1 m and 5 m from the closest edge of the sidewalk | 1) Face masks constituted 31% (n = 274) of total plastic debris 2) 95% of disposable face masks, 3% reusable masks, and only 2 high-grade masks such as N95 and KN95 3) Disinfecting wipes constituted 25% of total plastic debris 4) 0–8.22 × 10−3 PPE m−2; mean density: 1.01 × 10−3 ± 1.55 × 10−3 PPE m−2 |
Ammendolia et al., 2021 |
| Canada | City | 750,000; 10 | Streets, Highway Montreal-Quebec | 1) 3 m wide ground surface survey by walking covering urban, town, and rural areas | 1) 0.0001 ± 0.00005 items m−2; 2) Per day total range 4 to 10 masks 3) 76% Surgical masks and 24% cloth masks |
France, 2021 |
| Turkey | City | 40,000; NR | Streets | 1) A perimeter of 1 km2 in three cities was surveyed and the masks found within these perimeters were collected. | 1) 30 to 96 face masks km2 2) Total 210 for Adana, 170 for Mersin, and 166 for Niğde region |
Akarsu et al., 2021 |
| Mexico | City | 36,536; 8 | Streets, under cars, and camping areas | 1) Surveyed 6 km radius of the pilgrimage site. 2) PPE litter was monitored along both sides of the road and pilgrimage camping sites. 3) Visually identified, counted, and photographed |
1) Abundance: 4.1 × 10−3–13.9 × 10−3 items m−2; mean density: 7.8 × 10−3 items m−2 2) White and colored (black, blue, pink, yellow and green) face masks were observed 3) 81% surgical face masks, 8% KN95, 5% cloth and 6% others (gloves, face shields) |
This study |
NR: Not reported; PPE: Personal Protective Equipment.