Sample collection and handling
A total of 200 samples of spices were taken from wholesalers and retailers in the Auckland (New Zealand) region over the period March–June 1999. The samples comprised pepper (n=80), cinnamon/cassia (23), chilli (12), curry powder (15), paprika (13) and mixed and miscellaneous (57). These spices were selected on the basis that they were known to be commonly consumed without undergoing cooking. Samples were sent overnight to an analytical laboratory (ESR, Gracefield Laboratory) and were frozen at 20C on receipt pending analysis. Analyses were carried out within 1 month, and experiments confirmed that the
samples were stable in the frozen state for this period