The Content of Cd and Pb in Herbs and Single-Component Spices Used in Polish Cuisine

Abstract

Spices and herbs play an important role in the human diet, mostly due to the presence of essential oils and high antioxidant activity. Therefore, the toxicity of metals raises concerns about the safety of consumption of spices and herbs. This paper examines the content of Cd and Pb in fresh and dried herbs and single-component spices that are the most popular in Polish cuisine: 100 samples of nine kinds of dried herbs, 184 samples of 15 kinds of fresh herbs and 148 samples of 14 kinds of loose single-component spices. The level of Cd and Pb was determined using the GF AAS method. The safety of herbs and spices for consumption was estimated based on the percentage intake of Cd and Pb compared with the tolerable intake (% TWI, % BMDL), chronic daily intake (CDI), target hazard quotient (THQ), hazard index (HI) and comparisons of the results of chemical analyses with the maximum admissible levels of Cd and Pb in Poland and in the European Union. Calculated per fresh weight of the product, dried herbs on average contained 0.134 ± 0.168 mg of Cd and 0.548 ± 0.161 mg of Pb per kg^-1, fresh herbs on average contained 0.004 ± 0.007 mg of Cd and 0.039 ± 0.033 mg of Pb per kg^-1, and the mean content of Cd in spices was 0.017 ± 0.019 mg per kg^-1 and 0.064 ± 0.050 mg of Pb. The % TWI, % BMDL, CDI, THQ and HI (Cd + Pb) for all the analysed products were lower than 1. The results do not imply a risk due to the supply of Cd and Pb with the diet to the human body, primarily due to the small intake of these products. However, it should be highlighted that the content of Cd in dried coriander and estragon and that of Pb in watercress, jiaogulan, celery, basil and dill exceeded the acceptable limit. Thus, their consumption for people from particularly sensitive groups such as babies, pregnant and breastfeeding women and people should be carefully limited.

Keywords: Cadmium; Herbs; Lead; Safety; Spices.

Fig. 1

Comparison of Cd (a) and Pb (b) levels in dried herbs, fresh herbs and spices, mg kg⁻¹ dry matter ^a,b,cMeans with different superscripts differ significantly at P < 0.05 by Duncan’s test

Fig. 2

Mean level of Cd (a) and Pb (b) in analysed dried herbs (leaves and stems), mg kg⁻¹ fresh matter; MPL, maximum permissible level [38] ^a,b,c,d,eMeans with different superscripts differ significantly at P < 0.05 by Duncan’s test

Fig. 3

Mean level of Cd (a) and Pb (b) in analysed fresh herbs, mg kg⁻¹ fresh matter; MPL, maximum permissible level [38] ^{a,b,c,d,e,f,g,h,i,j}Means with different superscripts differ significantly at P < 0.05 by Duncan’s test

Fig. 4

Mean level of Cd (a) and Pb (b) in analysed spices, mg kg⁻¹ fresh matter; MPL, maximum permissible level [38] ^{a,b,c,d,e,f,g,h,i,j}Means with different superscripts differs significantly at P < 0.05 by Duncan’s test