Localization of Contaminants in Onions and Garlic Compartments

The article studies the content of nitrates, radionuclides, salts of heavy metals in different botanical varieties of onion and garlic. It was found that the distribution of contaminants is determined, firstly, by transpiration stream, which in bulb vegetables is directed as follows: root → stem → buds covered with scales→ leaves. Of all the varieties of onion the excluders include such varieties as Globe, Yalta ruby, the accumulaters include Stirling F1, Kharkov-82, the indicators include Lubchik, Amphora, Bilyanka. Of all studied varieties of garlic, the excluders are such varieties as Kharkov purple, Manuylivskyy, the accumulaters - Merefa White, Prometheus, the indicators – Spas, Saki. Secondly, the distribution of contaminants in juicy scales is determined by the functioning of the barrier tissue - the epidermis. The epidermis covers every juicy scale on both sides. In this regard, the farther from the bud, the smaller contaminants accumulate in juicy scales. In addition, onion contained 2 times less nitrates, cesium and strontium radionuclides than garlic. Salts of copper and zinc accumulated in approximately equal amounts. The content of cadmium and lead in onion is much higher than that of garlic. Moreover, the excess of the maximum permittable amount is registered in onion of cadmium (all varieties except Amphora and Yalta Ruby), and in garlic excess of nitrates (Manuylivskyy varieties, Merefa White, Duchess, Prometheus