Determination of Nitrates Levels in Spinach and Lettuce in Albanian Market

Abstract
Vegetable consumption is constantly increasing since they provide substances such as minerals, vitamins, dietary fiber and bioactive substances useful for human health. At the same time their content of nitrates and nitrites has raise the consumer concern because when levels are in excess they can be a potential health risk. The purpose of this study was to analyze nitrate levels in spinach and lettuce produced in different regions of Albania and determines whether their estimated quantity exceeds allowed levels constituting a risk to human health and safety. Sampling of vegetables took place at random on retail market of Tirana and four other regions which are considered as the most important areas producing vegetables for consumption. The weight of the sample was at least 1 kg from different regions of the country. All the samples were put in paper bags and immediately submitted to the laboratory for analysis. In accordance with the procedure, the samples were homogenized within 24 hours of sampling. Most samples were prepared immediately after homogenization, while others were stored at low temperatures in the refrigerator. Highest nitrate levels were detected for both vegetables in Tirana and Berat markets compared to other regions. Taking into account the allowed levels of nitrate content in vegetables it was found that spinach and lettuce are within the permitted levels. Daily consumption of 100g of studied vegetables was found not to exceed acceptable daily intake (ADI) for nitrates. Our findings showed the need of further monitoring the content of nitrate and nitrite in vegetables in different regions, conditions and seasons.Keywords: nitrate, spinach, lettuce.