The greatest threats to the children’s health are indeed where they should be safer: homes, schools and t communities. Every year, more than five million children of 0 to 14 years of age die directly because of diseases related to their surroundings, most of them in the developing countries. They die of diarrhoea, respiratory affections, malaria and other diseases of vectorial transmission, traumatisms, and other present environmental threats inside and around their homes.
The unhealthy water, a deficient hygiene and cleaning, the pollution of the air (even the caused one by dirty domestic fuels used to cook and to warm), the smoke of tobacco, dangerous chemical agents and other environmental threats affect the children’s health in a more or less acute form.
The impact of the environmental exposures on the development of the children is difficult to evaluate. The range of alterations is wide, just as it is the number and variety of exposures that can affect their growth and physical, intellectual, emotional and social development. In the developed countries, the degree of pollution is smaller than in the developing countries, and the effects derived from the environmental pollution are, therefore, subtler and difficult to discriminate considering the amount of agents and factors that take part in the development of the pathological processes.
The relation between some pollutants and health should not be considered as an isolated issue. The contamination is multicausal: this means that there are several sources of exposure to a polluting agent: diet, air and water consumption amongst others. And each one of these causes can lead to different effects. Besides, we must consider there may be multiple human answers to these exposures. Several factors determine the susceptibility of each person; factors that change throughout their lives, such as age, nutritional or genetic factors, pre-existing diseases, etc.
The alterations of the development can arise through a delay of the intrauterine growth, congenital malformations, functional problems of growth, lacks (neurobehavioral, immunological, reproductive) and greater predisposition to the development of chronic diseases in the adult life, such as diabetes, cardiovascular disease or cancer.
The exposure to substances that can alter the hormonal homeostasis (endocrine disruptors) is more acute during maternal-infantile and infantile exposure. There is proof of an increase in the last decades of many presumably hormone depending pathologies, such as alterations of the masculine genital maturation, alterations in the testicular function and testicle and prostate cancer.
The exposure to organochlorine compounds and metals is strongly related to low birth weight, prematurity and delay in the longitudinal growth. They may also alter to the thyroid function and the neurological development. We don’t know yet the mechanisms by which the environmental toxics would produce a cognitive delay. A light decrease of the number of nervous connections at the beginning of the life could be extended to maturity and remarkably advance the appearance of diseases like dementia.
Air pollution, specially the one caused by the automotive traffic, as well as the consumption of polluted tap water, would delay the intrauterine growth and would influence in the increase of certain congenital malformations. In addition, an important number of studies indicate that the exposure to elevated levels of atmospheric pollutants is associated to the increase of respiratory diseases such as bronchitis or crisis of asthma.