Lead toxicology: Implication of toxicity in pregnancy, infants, and children

Lead is a bluish-grey metal with a low melting point, high malleability occurring naturally in the earth's crust. Lead is mostly found in a combined state i.e. in combination with two or more elements to form lead compounds. As lead is non-biodegradable in nature, it is used in many manufacturing industries like ammunition, paint, storage batteries, smelting, alloy, pottery, cosmetics, etc. The effects of lead on the human body are devastating. The amount of lead in the environment is increasing exponentially due to human activities. Researchers said that the environmental level of lead has increased more than 1,000 fold over the last three centuries. There are many sources by which lead can enter the human body like occupational exposure, cosmetics, smoking, lead-glazed ceramic potteries, and many more. Toxicity can enter the body from pathways of ingestion, inhalation, and direct contact by the skin. Usually, lead quantity in populations above 20–30 µg/dL and in children above 40µg/dL is considered toxic. Maternal lead exposure is the main concern as it can result in structural deformities in the baby born. This review focuses on lead toxicokinetics and its metabolic pathway, its effects on the fetus, and prenatal exposure to lead. As toxicant lead mixes with the blood making every function of the body difficult, it mainly affects neuropsychological, hematopoietic, cardiovascular ocular, behavioral, renal, gastrointestinal, musculoskeletal, and endocrine phenomenon resulting in many disorder related to body functioning depending on the period of exposure like anemia, ataxia, impaired consciousness, abdominal pain, muscular pain, memory loss, osteoporosis, hypertension, and even cancer.