Health implications of mercury exposure in children

Abstract

Mercury is a ubiquitous environmental toxin that can produce a wide range of health effects in humans. It is found in three chemical forms: organic, inorganic and elemental (mercury). The sources of exposure are also markedly different for the different forms of mercury. Diet, especially fish and other seafood, is the main source of exposure of the general public to organic mercury. Dental amalgam is the most important source for elemental mercury vapour in the general population. Inorganic mercury compounds are known as 'mercuric salts', which are sometimes used in skin-lightening creams and as antiseptic creams and ointments. Though its use has been banned in some countries, these products are still available on the world market. Each mercury form possesses a different risk to human health. Mercury can be transferred prenatally to the developing foetus via the placenta or postnatally from breast milk to the nursing infant. Children are potentially more susceptible to mercury than adults due to differences in the stages of brain development and organ growth that occur during the foetal, infant and childhood developmental periods. The objective of this paper is to review the relevant literature concerning transplacental and lactational exposure to mercury, taking into account mercury speciation, in order to have a critical assessment of its adverse health effects. Attention is also given to available studies in Saudi Arabia where skin-lightening creams, dental amalgam and thimerosal are still in use.