In the Experimental Station of the National Research Institute of Animal Production in Grodziec Slaski, situated on the territory of the Cieszyn Silesia, there was conducted research concerning the levels of soil and pasture land contamination with heavy metals, such as lead, cadmium, cooper and zinc, as well as milk, meat, liver and kidneys of the cows pastured on the pasture land situated along the DK1. The preliminary research, which was carried out in 1998, revealed that despite high emission of the industrial pollutants and heavy traffic, the environment contamination is only slight. Furthermore, the amount of cadmium in soil increased, but there was not direct relation between the amount of the chemical elements in the pasture land to their amount in soil. The content of lead and cadmium in milk was normal. In comparison to the year 1998, in 2003 there was an increase in the content of lead and zinc in soil, whereas, change in the level of cadmium and copper was only inconsiderable. In 2009, the content of the heavy metals decreased significantly in comparison with the level from the year 2003. In the pasture land, which consisted in 65% of grass and in 18% of leguminous plants with dominance of Trifolium repens, the level of metals in the plants decreased. There were not found any regular alterations in the content of the metals in the soil depending on the distance from the road from 0 to 50 m. The further we went, the lead content became smaller, whilst with regard to the remaining elements the differences were not in any way significant. Moreover, the further we went away from road, the more lead could be found in the pasture land. The content of the metals in the pasture land and soil was analysed during the growing season, and the samples of soil were taken in April, May, July and September. It turned out that differences were found only in cadmium, the amount of which was decreasing. The amount of lead was also slightly diminishing. The highest contamination in the pasture land was found in May and the lowest in autumn. In 2003, the content of lead in milk was higher than in 1998. Moreover, it was shown in the research that the cows are susceptible to contamination of the environment with the lead which deposits in meat and liver, especially at the beginning of the growing season. There was more lead in the cow's milk cheese than in milk with the difference being the highest in April and it was decreasing during the growing season. In May, the amount of cadmium was lower in milk. The cadmium and lead were depositing mostly in liver, and their amount in this organ was higher in autumn than in spring. Furthermore, the content of the cadmium in meat was much higher than the acceptable level. There have been found positive, although statistically insignificant, correlation coefficients between the content of the lead and cadmium in the pasture land and the animal products such as milk or meat. For the food safety, the green forage intended for the farm animals which grows in the vicinity of some traffic route should be tested for the presence of the heavy metals.
