A total of 27 cleaning products, including surface, kitchen and floor cleaners as well as laundry and dishwashing liquid detergents, were obtained from a local supermarket. Due to the viscous nature of most of the analysed samples, and in order to facilitate their manipulation and introduction into the injection system, a dilution step was carried out. For sample dilution, 5 mL of methanol were added to about 200 mg of the sample previously weighed in a 15 mL glass vial. Anthracene was added as internal standard (80 ng mL−1), and the mixture was submitted to ultrasounds in a bath for 5 min in order to homogenise the solution.