Microbial communities and the interaction with heavy metals (and metaloids); impact and adaptations.

LIMA, A; URBIETA, M. S.; DONATI, E. R.

Heavy metals in the environment: microorganisms and bioremediation

Taylor & Francis Group

Año: 2017; p. 1 - 12

The millenary activity of extracting heavy metals (HM) is nowadays considered to be one of the main economic activities of the world with México, Chile, China and Australia being some of the countries with higher productions. Due to their particular properties, HM were and still are, used in many industries and production activities. Consequently, HM consumption has increased at a higher rate than population which has led to the generation and accumulation of tons of wastes. The inappropriate disposal of HM wastes has caused their mobility into the environment causing serious alterations in the ecosystems and triggering health problems in populations close to the polluted areas. The mobility of HM and metalloids into the environment also increases their distribution (especially in water systems) and bioavailability. The mobility and bioavailability of these pollutants are controlled by many chemical and biochemical processes such as precipitation/dissolution, sorption/desorption, complexation/dissociation and oxidation/reduction. The increase in HM and metalloids concentration in the environment directly affects microbial diversity, community structure and metabolic activity. It also causes the disappearance of susceptible species and the increase of tolerant species and/or the increase of the expression of resistance mechanisms (Zampieri et al., 2016).