No, lead levels are not accumulative. The body excretes lead from the blood stream in a process called "chelation". The body does this naturally but certain chemicals will speed up the process.
Here is a narrative taken from "Healthy Homes Collaborative Magazine " article on lead.
Is there treatment for lead poisoning?
There is chelation (pronounced key-la-tion) therapy, which is dangerous and generally reserved for cases of high level lead poisoning in order to rapidly lower the blood lead level. Chelation removes lead and other minerals from the blood, but it may also stimulate lead that has been stored in the bones to be released into the bloodstream, which can actually increase the level of lead in the blood. Chelation can also remove important minerals from the blood, which can be fatal.
Can the damage from lead poisoning be reversed?
Lead poisoning is essentially a permanent condition, which involves quasi-permanent damage in that little or no recovery occurs. It is generally accepted that the cognitive damage from lead poisoning is irreversible. Lead is also known to reduce recovery from all types of brain damage. Currently, the only viable "treatment" is to prevent lead exposure by removing the lead source.
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