Soil and human health [articol]

Abstract

There is a set of properties which differentiate the soils among each other, such as the texture, the content of organic carbon, nitrogen, phosphorus, and potassium, and the content of minor nutrients (Mg, Ca, Fe) and micronutrients (Cu, B, Zn, Mn). The direct effects of soils on human health are from soils contribution to food production and human exposure to potentially toxic compounds and pathogens in soils. Humans may assimilate beneficial or toxic compounds in soil through direct or indirect pathways. The main pathways of direct exposure are: soil ingestion, inhalation dust, and dermal absorbtion. The main indirect exposure pathways of soil constituents are through the food chain or water. Soils are also a source of toxic inorganic and organic constituents, soil pathogen or antibiotics and other products that enhance human health. The study is based on a lot of soil survey reports. In order to improve human health it is necessary to reduce input of potentially toxic trace elements, pesticides and antibiotics better fertilizers with N, P, K and micronutrient, and efficient fertilizer usage. Among the macronutrients more problems puts the nitrogen in the shape of NO3, due to the risk of nitrate loss through leaching, surface runoff or denitrification. Soil can be a sink, interacting medium, or a source for many potential pollutants, such as heavy metals (Cu, Zn, Pb, Cd, Cr, Co, Hg, Mo, Se, Mn, Fe). Similar with macro-and microelements, soil pathogen can also be threat to the human health. The vast majority of pathogens resist from some days to some weeks. For example, for Escherichia coli, the span of survival is circa 60-70 days, for tuberculosis, bacillus is about 7-18 months.