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Abstract: Extensive cadmium and lead contamination of water has been reported to occur locally as a result of human activities. Lactic acid bacteria have been reported to remove cadmium and lead from water. The aim of this work was to clarify the mechanisms of cadmium and lead removal from water. In addition, the effect of other metals, reversibility of binding and recyclability of the biomass was assessed. Based on our earlier data, the two most promising lactic acid bacteria, Lactobacillus fermentum ME3 and Bifidobacterium longum 46, were selected for these experiments. The results showed that the presence of other cationic metals and blocking of carboxyl and phosphoryl groups reduced cadmium and lead removal. These results suggest involvement of electrostatic interactions in cadmium and lead removal, and support our earlier findings. Transmission electron micrographs showed large deposits of lead on the bacterial surface suggesting formation of metallic lead precipitates. Both cadmium and lead removal were reversible processes established by full recovery of removed metal after desorption with dilute solutions of EDTA and HNO3. Resorption capacity of both biomasses tested was reduced after regeneration with 10 mM EDTA and 15 mM HNO3. Taken together, the results suggest involvement of several reversible mechanisms such as ion exchange and precipitation in cadmium and lead binding by lactic acid bacteria. The results show that specific lactic acid bacteria have the potential for removal of cadmium and lead from water although reduction in resorption capacity after regeneration of the biomass may form a problem. Since the studies so far have mainly focused on removal of single metals from pure water, metal removal in conditions of natural waters should be assessed in further experiments. [Copyright &y& Elsevier]

Maternal sensitivity behavior and infant behavior in early interaction were investigated among 57 Finnish mother–child pairs. Their interaction was video-recorded at home in free-play situation when the infants were 3 months and 12 months of age, and evaluated using the Parent–Child Early Relational Assessment Scale (PCERA). Maternal sensitivity behavior was mainly related to infant's positive aspects of mood, social and play behavior, and visual contact, both at 3 months and 12 months of age. Even though maternal sensitivity behavior correlated to infant behavior at 3 months and 12 months, infant behavior at 3 months of age contributed to later maternal sensitivity behavior. ©2001 Michigan Association for Infant Mental Health. [ABSTRACT FROM AUTHOR]