Accumulation and Depletion of Cadmium in the Blood, Milk, Hair, Feces, and Urine of Cows During and After Treatment

Effects of Heavy Metal Exposure from Leather Processing Plants on Serum Oxidative Stress and the Milk Fatty Acid Composition of Dairy Cows: A Preliminary Study

This study investigated whether unsaturated fatty acids in milk and the oxidative status of cows are affected by heavy metal exposure due to leather processing. The blood lead (Pb) concentrations in cows from two farms in the polluted area were 16.27 ± 8.63 μg/L, respectively, which were significantly (p < 0.05) higher than the blood Pb concentrations in cows from an unpolluted farm (6.25 ± 3.04 μg/L). There were significantly (p < 0.05) lower levels of glutathione S-transferase (GST), glutathione peroxidase (GPX), and glutathione (GSH) in the serum of cows from the polluted area compared to the levels in cows from an unpolluted area. The linoleic acid (C18:2n6c) content in milk from the polluted area was 15% lower than in the control area. There was a significant correlation between linoleic acid in milk with the blood Pb and serum GSH levels. Heavy metals can alter fatty acid synthesis through oxidative stress, which may be the mechanism by which heavy metals affect fatty acid synthesis in milk.

Heavy metals in blood, milk and cow's urine reared in irrigated areas with wastewater

The aim of this work was to determine the content of lead (Pb), chromium (Cr), cadmium (Cd), arsenic (As), copper (Cu), strontium (Sr) and thallio (Tl) in blood, milk and urine from cows fed forage irrigated with sewage water and cultivated in the vicinity of the Popocatépetl volcano and determine the rate of transfer of these elements from blood to milk and urine. Digestion was performed in a microwave oven (CEM-MarsX). The determination was made using an ICP -OES. The Cd in the blood was significantly higher than in milk and urine. The Cr in the blood was higher than in the urine. In milk the content of Pb and Cu was significantly higher than in blood. Sr and Tl concentration in the urine was higher than that detected in milk and blood and Pb in blood. Milk transfer Index revealed a significant difference in relation to the TI values found in the urine and only in the case of Cu in milk was TI > 1. In urine, the values found of Sr and Tl were higher than milk TI. It is concluded that when metals are ingested by cows in fodder, they are easily transferred to milk and urine through the blood. Presence of heavy metals in the different matrices determines the degree of environmental and trofic chain contamination with which we can consider the cow a biomarker.

Trace elements bioaccumulation in liver and fur of Myotis myotis from two caves of the eastern side of Sicily (Italy): A comparison between a control and a polluted area

Environmental pollution is a topic of great interest because it directly affects the quality of ecosystems and of all living organisms at different trophic and systematic levels. Together with the global climate change, the long-term surviving of many species of plants and animals is threaten, distributional patterns at global and regional levels are altered and it results in local assemblages of species that are quite different from those that currently constitute coevolved communities. .For this study, the species Myotis myotis was used as bioindicator and it was sampled from two caves in the south-east of Sicily, Pipistrelli chosen as control area and Palombara chosen as polluted area, to measure the concentrations of trace elements in fur and liver tissues. Results showed higher content of essential elements in fur in bats sampled from Pipistrelli. Conversely, higher concentrations of toxic metals in liver such as As, Cd, Pb and Hg were measured in bat samples in Palombara cave, where specimens have a hunting area extended within the boundaries of the petrochemical plant. Nevertheless, we cannot consider Palombara population as polluted by metal contamination since their tissue concentrations are overall lower than toxic thresholds values suggested for small mammals. Likewise, we cannot exclude other kind of pollutants as potential stressors of the examined population, contributing with the decreasing of bat colonies in Sicily.