Background
Methods
Study design
Sample treatment and detection
Preparation of standard curve
Quality control
Statistical analysis
Results
Pesticides | Recovery (%) | RSD (μg/mL) | R2
| LOD (mg/kg) | LOQ (mg/kg) | MRLb (mg/kg) |
---|---|---|---|---|---|---|
Acephate | 87.5 | 0.04–20 | 0.9996 | 0.005 | 0.017 | 0.02 |
Carbaryl | 89.3 | 0.10–20 | 0.9996 | 0.025 | 0.083 | 1 |
Carbofuran | 89.8 | 0.10–20 | 0.9997 | 0.025 | 0.083 | 0.5–2 |
Chlorpyrifos | 96.1 | 0.04–20 | 0.9995 | 0.005 | 0.033 | 0.5 |
Cyhalothrin | 106.4 | 0.02–20 | 0.9994 | 0.005 | 0.017 | 0.2 |
Cypermethrin | 93.2 | 0.02–20 | 0.9996 | 0.005 | 0.017 | 0.5 |
Decamethrin | 101.7 | 0.02–20 | 0.9993 | 0.005 | 0.017 | 0.2 |
Dichlorvos | 93.6 | 0.04–20 | 0.9995 | 0.005 | 0.033 | 0.02 |
Dicofol | 106.9 | 0.04–20 | 0.9995 | 0.005 | 0.017 | 0.01–1 |
Dimethoate | 104.7 | 0.04–20 | 0.9996 | 0.005 | 0.017 | 1 |
Ethion | 93.8 | 0.04–20 | 0.9991 | 0.01 | 0.033 | 0.05 |
Ethoprophos | 82.4 | 0.04–20 | 0.9994 | 0.01 | 0.017 | 0.01 |
Fenitrothion | 88.5 | 0.04–20 | 0.9992 | 0.005 | 0.017 | 0.2 |
Fenthion | 88.4 | 0.04–20 | 0.9994 | 0.01 | 0.017 | 0.05–1 |
Fenvalerate | 109.1 | 0.02–20 | 0.9992 | 0.005 | 0.017 | 0.05 |
Isazofos | 83.1 | 0.04–20 | 0.9991 | 0.005 | 0.017 | 0.03 |
Malathion | 85.6 | 0.04–20 | 0.9994 | 0.01 | 0.017 | 0.5 |
Methidathion | 86.6 | 0.04–20 | 0.9993 | 0.005 | 0.017 | 0.02 |
Methomyl | 87.1 | 0.10–20 | 0.9991 | 0.025 | 0.083 | 1 |
Metolcarb | 81.4 | 0.10–20 | 0.9995 | 0.025 | 0.083 | 0.05–1.0 |
Monocrotophos | 93.7 | 0.04–20 | 0.9998 | 0.005 | 0.017 | 0.01 |
Omethoate | 84.6 | 0.04–20 | 0.9997 | 0.005 | 0.033 | 0.02 |
Parathion | 94.2 | 0.04–20 | 0.9996 | 0.005 | 0.033 | 0.05 |
Parathion-methyl | 91.9 | 0.04–20 | 0.9997 | 0.01 | 0.033 | 0.1–0.5 |
Permethrin | 92.7 | 0.02–20 | 0.9997 | 0.005 | 0.017 | / |
Phorate | 90.2 | 0.04–20 | 0.9995 | 0.005 | 0.017 | 0.2–0.5 |
Phosmet | 91.7 | 0.04–20 | 0.9992 | 0.005 | 0.017 | 0.5 |
Phoxim | 89.4 | 0.04–20 | 0.9996 | 0.005 | 0.017 | 0.05 |
Pirimicarb | 89.3 | 0.10–20 | 0.9995 | 0.025 | 0.083 | 0.02 |
Propoxur | 76.9 | 0.10–20 | 0.9993 | 0.025 | 0.083 | 0.01 |
Quinalphos | 91.6 | 0.04–20 | 0.9997 | 0.01 | 0.033 | 0.2 |
Trichlorfon | 92.3 | 0.10–20 | 0.9995 | 0.01 | 0.017 | 0.01 |
Vegetables | Samples | Number of samples | Samples with residues above MRLs | ||||
---|---|---|---|---|---|---|---|
Total | 2011 | 2012 | 2013 | NO. | Rate (%) | ||
Leafy vegetables | Baby cabbage | 12 | 4 | 4 | 4 | 1 | 8.3 |
Brassica chinensis
| 28 | 8 | 10 | 10 | 4 | 14.3 | |
Cabbage | 28 | 8 | 10 | 10 | 4 | 14.3 | |
Cauliflower | 25 | 6 | 9 | 10 | 2 | 8 | |
Celery | 30 | 8 | 10 | 12 | 7 | 23.3 | |
Chinese cabbage | 24 | 6 | 8 | 10 | 2 | 8.3 | |
Leek | 30 | 8 | 10 | 12 | 5 | 16.7 | |
Lettuce | 27 | 8 | 9 | 10 | 0 | 0 | |
Pakchoi | 26 | 8 | 8 | 10 | 2 | 7.7 | |
Spinach | 28 | 8 | 10 | 10 | 2 | 7.1 | |
Melon and fruit vegetables | Cowpea | 30 | 8 | 10 | 12 | 8 | 26.7 |
Cucumber | 30 | 8 | 10 | 12 | 2 | 6.7 | |
Eggplant | 28 | 8 | 10 | 10 | 0 | 0 | |
Green pepper | 28 | 8 | 10 | 10 | 0 | 0 | |
Kidney bean | 28 | 8 | 10 | 10 | 0 | 3.6 | |
Pumpkin | 26 | 8 | 8 | 10 | 0 | 0 | |
Tomato | 26 | 8 | 8 | 10 | 0 | 0 | |
Root vegetables | Carota | 26 | 8 | 8 | 10 | 0 | 0 |
Potato | 26 | 8 | 8 | 10 | 0 | 0 | |
Ternip | 12 | 4 | 4 | 4 | 1 | 8.3 | |
Total | 518 | 148 | 174 | 196 | 40 | 7.7 |
Vegetables | Samples | Samples with residues above MRL | χ2
|
P
| |
---|---|---|---|---|---|
NO. | Rates (%) | ||||
Leafy | 258 | 29 | 11.2 | ||
Melon And Fruit | 196 | 10 | 5.1 | 9.907 | 0.007 |
Roots | 64 | 1 | 1.6 |
Sale sites | Samples | Samples with residues above MRL | χ2
|
P
| |
---|---|---|---|---|---|
NO. | Rates (%) | ||||
Supermarket | 246 | 9 | 3.7 | 12.031 | 0.002 |
Wholesale market | 135 | 13 | 9.6 | ||
Trade market | 137 | 18 | 13.1 |
Types | Sample numbers | Samples with residues above MRL | χ2
|
P
| |
---|---|---|---|---|---|
NO. | Rates (%) | ||||
Vegetables in winter and spring | 224 | 13 | 5.8 | 2.038 | 0.153 |
Vegetables in summer and autumn | 294 | 27 | 9.2 | ||
Anti-seasonal Vegetables | 124 | 12 | 9.7 | 0.875 | 0.350 |
Seasonal Vegetables | 394 | 28 | 7.1 | ||
Organic Vegetables | 98 | 1 | 1.0 | 7.619 | 0.006 |
Conventional Vegetables | 420 | 39 | 9.3 |
Pesticides | Maximum value detected (mg/kg) | Samples with residues above MRLs | Pesticides | Maximum value detected (mg/kg) | Samples with residues above MRL | ||
---|---|---|---|---|---|---|---|
NO. | % | NO. | % | ||||
Malathion | 2.256 | 14 | 9.4 | Dicofol | 7.129 | 4 | 2.6 |
Dichlorvos | 2.226 | 13 | 8.7 | Trichlorfon | 1.546 | 3 | 2 |
Dimethoate | 4.496 | 12 | 8.1 | Fenvalerate | 0.856 | 3 | 2 |
Omethoate | 3.922 | 10 | 6.7 | Acephate | 2.542 | 2 | 1.3 |
Carbofuran | 0.186 | 9 | 6.1 | Methidathion | 0.038 | 2 | 1.3 |
Ethoprophos | 0.028 | 9 | 6 | Quinalphos | 0.468 | 2 | 1.3 |
Isazofos | 0.031 | 8 | 5.4 | Propoxur | 5.566 | 2 | 1.3 |
Monocrotophos | 0.11 | 8 | 5.4 | Pirimicarb | 1.858 | 2 | 1.3 |
Metolcarb | 8 | 5.4 | Permethrin | 2.566 | 2 | 1.3 | |
Cypermethrin | 1.738 | 7 | 4.7 | Cyhalothrin | 1.438 | 2 | 1.3 |
Phorate | 1.432 | 6 | 4 | Fenitrothion | 0.13 | 1 | 0.7 |
Parathion-methyl | 0.884 | 6 | 4 | Fenthion | 0.03 | 0 | 0 |
Parathion | 1.658 | 4 | 2.7 | Phoxim | 0.025 | 0 | 0 |
Chlorpyrifos | 1.884 | 4 | 2.7 | Phosmet | 0.168 | 0 | 0 |
Ethion | 0.082 | 4 | 2.7 | Carbaryl | 0.28 | 0 | 0 |
Methomyl | 3.974 | 2 | 2.7 | Deltamethrin | 0.045 | 0 | 0 |
Vegetables | No. of samples | No. of samples exceeding the MRLs | Name of pesticides detected above the MRLs |
---|---|---|---|
Spinach | 28 | 2 | (1):Dichlorvos, Ethoprophos |
(2):Malathion | |||
Leek | 30 | 5 | (1):Dichlorvos, Malathion, Omethoate, Trichlorfon |
(2):Dichlorvos, Dimethoate, Isazofos, Fenvalerate | |||
(3):Malathion, Dimethoate, Monocrotophos | |||
(4):Dimethoate, Ethoprophos, Cypermethrin | |||
(5):Omethoate, Carbofuran, Phorate | |||
Cabbage | 28 | 4 | (1):Dichlorvos, Ethoprophos, Trichlorfon, Acephate |
(2):Dichlorvos, Omethoate, Monocrotophos | |||
(3):Malathion, Metolcarb, Dicofol | |||
(4):Dimethoate, Isazofos, Chlorpyrifos | |||
Celery | 30 | 7 | (1):Dichlorvos, Malathion, Ethoprophos, Cypermethrin, Parathion |
(2):Dichlorvos, Dimethoate, Carbofuran, Parathion-methyl | |||
(3):Cypermethrin, Parathion-methyl, Phorate, Parathion, Methidathion | |||
(4):Dichlorvos, Omethoate, Isazofos, Ethion | |||
(5):Malathion, Dimethoate, Monocrotophos, Parathion, Cyhalothrin | |||
(6):Dimethoate, Carbofuran, Cypermethrin, Ethion | |||
(7):Omethoate, Metolcarb, Parathion-methyl, Dicofol, Methidathion | |||
Green pepper | 28 | 4 | (1):Dichlorvos, Metolcarb |
(2):Malathion, Fenvalerate | |||
(3):Dimethoate, Monocrotophos | |||
(4):Metolcarb, Propoxur | |||
Cauliflower | 25 | 2 | (1):Dichlorvos, Isazofos, Propoxur, Permethrin |
(2):Malathion, Ethoprophos, Carbofuran | |||
Chinese cabbage | 24 | 2 | (1):Malathion, Metolcarb, Monocrotophos, Fenitrothion |
(2):Chlorpyrifos, Isazofos, Dicofol, Methomyl | |||
Pakchoi | 26 | 2 | (1):Omethoate, Carbofuran, Ethion |
(2):Malathion, Metolcarb, Cypermethrin | |||
Baby cabbage | 12 | 1 | (1):Malathion, Ethoprophos, Monocrotophos, Parathion-methyl, Methomyl |
Cucumber | 30 | 2 | (1):Dichlorvos, Carbofuran, Metolcarb, Isazofos |
(2):Malathion, Ethoprophos, Phorate, Pirimicarb | |||
Cowpea | 30 | 8 | (1):Dichlorvos, Malathion, Omethoate, Cypermethrin, Ethion, Fenvalerate |
(2):Dichlorvos, Dimethoate, Carbofuran, Phorate, Chlorpyrifos, Acephate | |||
(3):Omethoate, Ethoprophos, Parathion-methyl, Trichlorfon | |||
(4):Malathion, Dimethoate, Monocrotophos, Phorate, Pirimicarb | |||
(5):Dimethoate, Carbofuran, Cypermethrin, Parathion, Quinalphos | |||
(6):Dimethoate, Ethoprophos, Parathion-methyl, Chlorpyrifos | |||
(7):Omethoate, Carbofuran, Monocrotophos, Dicofol, Cyhalothrin | |||
(8):Phorate, Omethoate, Isazofos, Quinalphos, Permethrin | |||
Ternip | 12 | 1 | (1):Metolcarb, Isazofos |
Total | 518 | 40 | 149 |