Table 7.

Comparison of various extraction techniques for pesticides in solid samples.

Extraction Technique	Cost, T, and P	Solvent Type/Solvent Consumption/Extraction Time	Advantages	Disadvantages	References
Soxhlet	low cost boiling point of solvent atm. pressure	organic solvent 60–500 mL 6–24 h	It does not require filtration; samples in large amounts; easy to operate; does not depend on the matrix	Extraction time is long; large consumption of solvents; sample must be preconcentrated after extraction	[47,48]
supercritical fluid extraction (SFE)	high cost 70–150 °C 15–50 MPa	CO2 10–40 mL 30–60 min	Friendly to the environment because it is not toxic; extraction is fast; uses little solvent; does not require filtration	Sample size limited; dependent on the matrix and analyte	[49]
ultrasonic-assisted extraction (UAE)	low cost 30–35 °C Atm. pressure	organic solvent 30–100 mL 30–60 min	Fast and easy to operate; large amount of sample; does not depend on the matrix	Risk of being exposed to the solvent vapour; large amount of solvent, labour intensive; requires filter	[45,46]
microwave-assisted extraction (MAE)	moderate cost 100–150 °C Atm. pressure	organic solvent 10–40 mL 20–30 min	Uses small solvent and is fast full control of extraction parameters	Filtration required; solvent must be polar; exhaustive extraction	[48]
Pressurized liquid extraction (PLE)	high cost 100–150 °C 7–15 MPa	organic solvent 10–60 mL 10–60 min	Uses small solvent and is fast; does not require filtration and is easy to use	Extraction efficiency dependent on matrix	[45,50]
subcritical water extraction (SWE)	moderate cost 200–300 °C 5 MPa	water 30–60 mL 30–60 min	Uses water, which is non-toxic, fast, friendly to the environment; uses little solvent	Optimization of operating conditions required	[45]

T = temperature, P = pressure, atm. pressure = atmospheric pressure.