| Popis: |
Tobak (Nicotiana tabacum) je eden izmed vodilnih produktov potrošniške družbe. Njegova uporaba predstavlja grožnjo javnemu zdravju, saj lahko tobak zaradi kopičenja potencialno nevarnih kovin (PNK) poleg katrana, ogljikovega monoksida in nikotina škodljivo vpliva na človeško telo. Namen diplomskega dela je na osnovi znanstvenih virov predstaviti najpogostejše vire PNK v tobaku, vsebnosti kovin v tleh, kjer pridelujejo tobak, mehanizme privzema PNK iz tal v tobak ter dejavnike vpliva, kot so talne lastnosti, sorte tobaka in kmetijske prakse. Skozi pregledane raziskave je bilo ugotovljeno, da je najpogostejši vir PNK v tobaku uporaba fosfatnih gnojil. Mehanizmi kopičenja kovin v tobaku omogočajo prenos PNK iz tal v korenine, nato v nižje ležeče liste, čemur sledi prehajanje v višje rastoče liste tobaka. Prisotnost PNK v tleh se razlikuje glede na onesnaženost območij, kjer gojijo tobak. Največ PNK se nahaja v tobaku, ki ga gnojijo z gnojili z večjo vsebnostjo PNK. Nanašanje fitofarmacevtskih sredstev (FFS) preko tal povzroči manjše vsebnosti PNK v tobaku v primerjavi s pršenjem na vršičke tobaka. Sorta tobaka prav tako lahko vpliva na sprejem PNK v rastlino. Vendar v nobeni raziskavi ni bila ugotovljena problematična vsebnost kovin v tobaku. Tobacco (Nicotiana tabacum) is one of the leading articles of human consumption. Its use represents a threat to public health, due to its ability to accumulate potentially hazardous metals (PHM) as well as tar, carbon monoxide and nicotine, which can have a harmful effect on the human body. The purpose of the bachelor’s thesis was to review of previous publications on the most common sources of PHM in tobacco, the content of metals in soils where tobacco is grown, the mechanism of PHM uptake from soil into tobacco, and the influencing factors (soil properties, type of tobacco, agricultural practices). Review of research results showed that the most common source of PHM in tobacco is the use of phosphate fertilizers. The mechanisms of PHM accumulation in tobacco allow the transfer of PHM from soils to the lower leaves, and then the PHM transfers to the higher growing tobacco leaves. The presence of PHM in soil varies depending on the contamination of the tobacco growing areas. More PHM is found in tobacco fertilized with a higher PHM content in fertilizers. The application of plant protection products (PPPs) on the soil results in lower PHM values in tobacco compared to spraying of tobacco tops. Tobacco variety also affects PHM uptake into the plant. Several studies were conducted, however none of them detected problematic metal content in tobacco. |
