Lead Poisoning: Effects and Causes

Lead was mined for the first time, in Turkey, around 6500 B.C and its toxicity was recognized by 200 B.C. This metal has been an active ingredient in paints, lead-glazed ceramic ware, water pipes, gasoline, metal jewelery, batteries, solder, cosmetics etc. During the seventies, the usage of this metal was curtailed to some extent through legislation.

Lead poisoning occurs due to the increased levels of this metal in the blood. This happens by the absorption of this metal, into the human body, through breathing or swallowing. Sometimes, even small amounts of lead can be toxic, especially for children. Lead poisoning can result in severe mental and physical disorders in small children. Even though, the toxicity of this metal affects both adults and kids, it is more severe and frequent in children below the age of six. Let us understand the various effects and causes of lead poisoning.

Effects of Lead Poisoning

Normally, a very small amount of lead is present in the human body. If the lead content is higher than normal, it can damage almost every organ, but the highly-affected parts are the kidneys, nervous system and the brain. A blood lead level of 10 ug/dL (micro grams per deciliter) or higher, in children, is a cause for concern. This can result in mental retardation and other cognitive and behavioral problems in kids. A blood lead level of 80 ug/dL and above, is fatal for adults, but lower lead content (25 ug/dL to 80 ug/dL) can also cause health problems.

Chronic lead poisoning leads to neurological disorders, like reduced cognitive abilities (perception, learning and reasoning). The peripheral and the central nervous system are affected by this metal. High blood lead level can result in peripheral neuropathy (nerve disorders of the peripheral nervous system), which is characterized by wrist drop (weakness of the extensor muscles of the hand). Low levels are associated with decrease in the neuro-cognitive function. In children, even low blood lead level can cause permanently reduced cognitive capacity (intelligence).

Lead poisoning can also cause insomnia, impotence, chest pain, headache, excess fatigue or hyperactivity, irritability, coma and sometimes death. It is also imputed to be one of the reasons for nausea, abdominal pain, constipation, vomiting, diarrhea, weight loss, anemia, kidney problems, blue lines along the gums and high blood pressure. Children may experience slow growth, hearing problems, staggering, behavior problems, learning problems, headaches, convulsions, drowsiness and confusion.

Causes of Lead Poisoning

Lead is present in the earth's crust in a very small quantity, but human activities like mining, manufacturing and usage of leaded gasoline have resulted in the widespread prevalence of lead poisoning. Regular usage of substances with a high lead content can lead to lead poisoning. It can be due to absorption of very low doses of lead over a stretch of time or high doses over a short period.

Adults, who work as welders, potters, metal smelters, etc, are at a greater risk of lead poisoning. Hobbies like shooting, working with stained glass, building lead-based models, etc, can also expose you to lead. Other than this, even tap water can also be contaminated with lead, if the water pipes are made of this metal, or if you are using brass plumbing fixtures and copper pipes soldered with lead. Even though, paints with lead are banned in the U.S., older homes and buildings have leaded paint on the walls and this can cause lead poisoning. Imported toys and pottery may contain lead. Soil contaminated with lead from gasoline and paint is another reason for lead poisoning. While household dust is another source, some imported canned foods may also contain lead. It has also been found that traditional medicines of some countries contain high levels of lead. In the case of cosmetics with a high lead content, 'kohl' is such an example.

Avoiding exposure to this metal can curtail the risk of lead poisoning. Don't allow your children to ingest paint flakes or soil. A little precaution can save you from this condition and help you lead a healthful life.