Background
Methods
Mosquito coils
ID No. | Country of origin | Shape | Color | Mass per coil (g) | Active ingredient indicated on package | Burning time (h) |
---|---|---|---|---|---|---|
MC 1 | China | Spiral | Black | 16.5 | 0.25% esbiothrin | 7.50 |
MC 2 | China | Spiral | Black | 20.0 | 0.03% dimefluthrin | 9.67 |
MC 3 | China | Spiral | Black | 17.5 | 0.03% dimefluthrin | 8.00 |
MC 4 | Spain | Spiral | Black | 16.6 | 0.20% allethrin | 8.00 |
MC 5 | China | Spiral | Black | 17.0 | 0.08% meperfluthrin | 8.00 |
Sampling and rearing of mosquitoes
Experimental chambers
Room size (m3) | Ventilated condition | Poorly ventilated condition | ||
---|---|---|---|---|
Temperature (°C) | Relative humidity (%) | Temperature (°C) | Relative humidity (%) | |
8.5 | 28.37 ± 1.96 | 70.77 ± 5.07 | 30.08 ± 1.90 | 66.24 ± 3.15 |
19 | 28.56 ± 0.81 | 71.77 ± 4.30 | 30.62 ± 1.40 | 66.10 ± 4.33 |
34 | 28.65 ± 0.81 | 69.53 ± 3.96 | 27.90 ± 0.54 | 67.09 ± 4.29 |
Mosquito mortality test
Emissions from mosquito coils
Gaseous emissions
Gas | Sensor type | Sensor range (mg/m3) | Minimum detection limit (mg/m3) |
---|---|---|---|
CO | GSE | 0–123 | 0.25 |
TVOC | PID | 0–70 | 0.03 |
NO2 | GSE | 0–2 | 0.01 |
SO2 | GSE | 0–28 | 0.11 |
Particulate matter
Risk characterization
Results and discussion
Susceptibility of mosquitoes to lit coils
Emissions from mosquito coils
Carbon monoxide (CO)
Mosquito coil | Ventilated conditionb | Poorly ventilated conditionc | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
CO | TVOC | NO2 | SO2 | PM2.5 | PM10 | CO | TVOC | NO2 | SO2 | PM2.5 | PM10 | |
Room size: 8.5 m3 | Room size: 8.5 m3 | |||||||||||
MC 1 | 1.91 | 0.05 | 0.08 | 0.34 | 0.02 | 0.15 | 17.93 | 0.12 | 0.07 | 0.90 | 0.11 | 0.19 |
MC 2 | 1.95 | 0.05 | 0.07 | 0.16 | 0.07 | 0.04 | 7.56 | 0.13 | 0.07 | 0.66 | 0.16 | 0.15 |
MC 3 | 1.83 | 0.08 | 0.08 | 0.24 | 0.07 | 0.05 | 11.20 | 0.14 | 0.07 | 0.36 | 0.41 | 0.32 |
MC 4 | 2.51 | 0.04 | 0.07 | 0.29 | 0.08 | 0.18 | 8.12 | 0.16 | 0.07 | 0.43 | 0.63 | 0.67 |
MC 5 | 2.15 | 0.07 | 0.08 | 0.20 | 0.03 | 0.03 | 21.09 | 0.15 | 0.07 | 0.86 | 0.09 | 0.09 |
Average | 2.07 | 0.06 | 0.08 | 0.25 | 0.06 | 0.09 | 13.18 | 0.14 | 0.07 | 0.64 | 0.28 | 0.28 |
Control | BDL | BDL | 0.07 | BDL | 0.02 | 0.03 | BDL | 0.05 | 0.06 | 0.16 | 0.07 | 0.05 |
Room size: 19 m3 | Room size: 19 m3 | |||||||||||
MC 1 | 2.66 | 0.03a | 0.08 | 0.37 | 0.04 | 0.11 | 18.75 | 0.12 | 0.07 | 0.99 | 0.17 | 0.24 |
MC 2 | 1.99 | 0.04 | 0.08 | 0.19 | 0.06 | 0.06 | 12.09 | 0.18 | 0.06 | 0.68 | 0.23 | 0.20 |
MC 3 | 5.04 | 0.03a | 0.08 | 0.16 | 0.09 | 0.05 | 10.15 | 0.19 | 0.06 | 0.38 | 0.31 | 0.44 |
MC 4 | 1.30 | 0.04 | 0.08 | 0.26 | 0.13 | 0.24 | 12.85 | 0.25 | 0.06 | 0.51 | 1.02 | 1.20 |
MC 5 | 3.10 | 0.06 | 0.08 | 0.13 | 0.04 | 0.03 | 32.60 | 0.19 | 0.07 | 1.00 | 0.23 | 0.10 |
Average | 2.82 | 0.04 | 0.08 | 0.22 | 0.07 | 0.10 | 17.29 | 0.19 | 0.06 | 0.71 | 0.39 | 0.44 |
Control | BDL | BDL | 0.07 | BDL | 0.02 | 0.02 | BDL | 0.05 | 0.05 | 0.25 | 0.06 | 0.06 |
Room size: 34 m3 | Room size: 34 m3 | |||||||||||
MC 1 | 2.33 | 0.03a | 0.07 | 0.23 | 0.04 | 0.15 | 14.21 | 0.12 | 0.06 | 0.96 | 0.09 | 0.19 |
MC 2 | 2.61 | 0.06 | 0.08 | 0.15 | 0.04 | 0.04 | 7.73 | 0.12 | 0.07 | 0.64 | 0.13 | 0.17 |
MC 3 | 4.91 | 0.06 | 0.07 | 0.26 | 0.06 | 0.10 | 9.86 | 0.12 | 0.07 | 0.44 | 0.23 | 0.33 |
MC 4 | 3.13 | 0.06 | 0.08 | 0.23 | 0.08 | 0.15 | 8.25 | 0.12 | 0.07 | 0.38 | 0.58 | 0.63 |
MC 5 | 2.42 | 0.05 | 0.08 | 0.25 | 0.06 | 0.02 | 22.15 | 0.11 | 0.08 | 0.86 | 0.15 | 0.14 |
Average | 3.08 | 0.05 | 0.08 | 0.22 | 0.06 | 0.09 | 12.44 | 0.12 | 0.07 | 0.66 | 0.24 | 0.29 |
Control | BDL | BDL | 0.07 | BDL | 0.03 | 0.02 | BDL | 0.06 | 0.06 | 0.15 | 0.05 | 0.04 |
Total volatile organic compounds (TVOCs)
Sulfur dioxide (SO2)
Nitrogen dioxide (NO2)
Particulate matter (PM)
Risk–benefit analysis of mosquito coil application
Pollutant | Min | Max | Mean | Std dev | 5th percentile | 95th percentile |
---|---|---|---|---|---|---|
CO | 5.0 × 10−14 | 2.9 × 10−8 | 2.7 × 10−9 | 2.4 × 10−9 | 1.7 × 10−10 | 7.4 × 10−9 |
TVOC | 4.1 × 10−16 | 3.5 × 10−10 | 5.0 × 10−11 | 4.3 × 10−11 | 3.3 × 10−12 | 1.4 × 10−10 |
NO2 | 8.6 × 10−16 | 3.5 × 10−10 | 7.7 × 10−11 | 6.0 × 10−11 | 5.4 × 10−12 | 1.9 × 10−10 |
SO2 | 2.7 × 10−15 | 2.4 × 10−9 | 2.3 × 10−10 | 2.1 × 10−10 | 1.5 × 10−11 | 6.3 × 10−10 |
PM2.5 | 0 | 9.1 × 10−10 | 6.2 × 10−11 | 6.0 × 10−11 | 3.5 × 10−12 | 1.8 × 10−10 |
PM10 | 1.7 × 10−15 | 2.0 × 10−9 | 9.0 × 10−11 | 1.2 × 10−10 | 3.5 × 10−12 | 3.1 × 10−10 |
Pollutant | Min | Max | Mean | Std dev | 5th percentile | 95th percentile |
---|---|---|---|---|---|---|
CO | 1.3 × 10−13 | 3.6 × 10−6 | 1.7 × 10−8 | 3.7 × 10−8 | 8.3 × 10−10 | 4.8 × 10−8 |
TVOC | 1.4 × 10−15 | 4.9 × 10−9 | 1.5 × 10−10 | 1.4 × 10−10 | 10.0 × 10−12 | 4.0 × 10−10 |
NO2 | 7.8 × 10−16 | 3.8 × 10−10 | 7.1 × 10−11 | 5.6 × 10−11 | 4.9 × 10−12 | 1.8 × 10−10 |
SO2 | 1.0 × 10−14 | 4.7 × 10−9 | 6.9 × 10−10 | 6.0 × 10−10 | 4.3 × 10−11 | 1.9 × 10−9 |
PM2.5 | 2.4 × 10−15 | 8.5 × 10−6 | 8.5 × 10−10 | 3.1 × 10−8 | 1.3 × 10−11 | 1.6 × 10−9 |
PM10 | 1.4 × 10−15 | 7.6 × 10−9 | 3.3 × 10−10 | 1.4 × 10−10 | 1.4 × 10−11 | 1.1 × 10−9 |