Cadmium Exposure in Children and its Impact on Health

Abstract

Ievads: Kadmija piesārņojums galvenokārt rodas metālrūpniecībā. Vispasaules līmenis vidē ir krasi pieaudzis cilvēka darbības dēļ. Tāpat kā citus smagos metālus, to ir grūti attīrīt no piesārņotajām vietām, un tas var ilgstoši negatīvi ietekmēt gan ekonomiku, gan veselību. Kadmiju cilvēka organisms var uzņemt caur gremošanas traktu vai elpošanas sistēmu. Pastāv noteiktas riska grupas, piemēram, cilvēki, kas strādā ar rūpnieciskām iekārtām vai dzīvo to tuvumā, vai smēķētāji. Cilvēki ar cinka vai dzelzs deficītu ir pakļauti riskam, jo palielinās uzsūkšanās zarnās. Dabā tas ir visuresošs, taču iedzīvotāju līmenī galvenie iedarbības avoti ir pārtikas produkti, piemēram, graudi, zaļie dārzeņi, jūras veltes. Mērķi: Šī zinātniskā pētījuma mērķis ir aplūkot jaunāko zinātnisko literatūru par kadmija ietekmi uz bērnu veselību un attīstību. Metodes: Šis darbs ir uzrakstīts, pamatojoties uz atlasītās literatūras apskatu. Raksti, grāmatas un publikācijas tika atrastas dažādās interneta meklētājprogrammās; tostarp ScienceDirect, Clinical Key, Cochrane Library, PubMed. Materiāls, uz kuru balstās šis darbs, ir atrodams šī darba bibliogrāfijas sadaļā.Cadmium pollution stems mainly from metal industry. Worldwide levels in the environment have risen drastically due to human activity. Like other heavy metals it is difficult to clean up from contaminated areas and can have long standing negative effects both on economy and health. Cadmium can be taken up by the human organism through the digestive tract or respiratory system. Certain risk groups exist, for example people working with or living close to industrial facilities or smokers. People with zinc or iron deficiency lie at risk due to increased intestinal absorption. It is ubiquitous in nature but seen on a populational level the main sources of exposure stems from food like grains, green vegetables, seafood.

Aims of this scientific research paper aims to look at recent scientific literature on the health and developmental effects of cadmium among children. The articles, books and publications to this thesis were found by different internet search engines; amongst them ScienceDirect, Clinical Key, Cochrane Library, PubMed.

Results: Children experience higher cadmium exposure in relation to their bodyweight. Children still developing and growing which means that negative consequences to health and wellbeing has an accumulative effect later in life. Harmful effects have been seen on especially tubular structures of kidneys and in skeletal system due to accumulation in bone. A correlation with cancers such as lung-, thyroid-, and prostate cancer has been seen. Mechanisms of damage are many. Cadmium can cause oxidative stress which can lead to altered DNA repair. Also, epigenetic alterations are seen. The commonly considered safe level of exposure has been lowered during the last 30 years due to observed adverse effects from decreasingly smaller exposure levels. Treatment from chronic exposure has been studied with chelating agents but show little clinical benefit. Human biomonitoring (HBM) can be done with certain markers mentioned in this thesis, no specific markers for cadmium monitoring has however been proposed. In children cadmium has been seen to cause decreased birth weight and placental changes. Hormonal changes as testosterone decrease have also been seen. Autoimmune disease like atopic dermatitis is associated with cadmium exposure. Neuropsychological, neurodevelopmental and cognitive impact has been studied in relation to cadmium exposure but the results are somewhat inconclusive. Some studies indicate no changes in neurodevelopment. Others saw decreased IQ scores in children with increased exposure. Other studies found IQ to be related not to cadmium but overall pollutant level instead. In animal studies cadmium has been shown to alter enamel formation during early development. Altered bone formation is also seen in animal studies through a decrease of stem cell proliferation.