Nature of the Material
Lead is a naturally occurring metal (element) that has been used by man since early times in such applications as water pipes because of its malleability and durability. It is poisonous in nearly all of its compounds, but despite its usefulness in many applications today which give little cause for concern, the presence of lead in paints (because it is resistant to corrosion) in addition to its being as antiknock additive to gasoline that have given rise to health and safety concerns.
Lead poisoning can result in brain damage or death, and while for adults it generally requires substantial cumulative exposures for harmful effects, in children brain damage occurs from much more limited exposure.
It is this fact that has caused regulations to focus on those lead applications, principally lead paint, which represent the greatest risk to be encountered by children, namely residential uses where lead contaminated paint can be ingested. A blood test is the general method for determining lead poisoning and the current definition, according to the Center for Disease Control, is 10ug/do of blood. In sharp contrast to asbestos where the latency for asbestos-caused diseases is 15 to 30 years, lead has no latency. Blood tests will indicate elevated blood levels of lead shortly after exposure by either ingestion or inhalation. This fact has significant implication in both the handling of contaminated material and the liability risks to abatement contractors.
Despite the fact that lead health risks as far back as Roman times, it was the Consumer Product Safety Commission in the late 1970’s that focused regulations on lead use and handling. Currently, laws and regulation governing the use, treatment and handling of lead have been promulgated on a federal level by EPA, OSHA, Consumer Product Safety commission, CDC, DOT and HUD. In Maine, regulations have come from the Bureau of Health and will soon come from the DEP. Some municipalities have also issued regulations, and Portland has done so through its Health Department and its Code Enforcement Department.
Methods of Abatement
The methods for lead abatement are the same as for asbestos encapsulation, enclosure, and removal; however, more than for asbestos economics tends to drive the method of abatement and removal is not always a priority. The same clean room technology utilized in asbestos work is also employed in lead abatement; although, when the removal process involves a wetting agent, as in chemical removal or water blasting, such elaborate containment is not required as the liquid prevents the contaminants from becoming airborne.
The removed material is bagged and tested for lead content. Depending on lead levels, the material may be classified as hazardous waste or solid waste (non hazardous). Concentrated paint scrapings might likely be classified as the former while wood trim pained with lead paint might be classified as the latter.
In the case of hazardous waste, licensed haulers are utilized to take the waste to licensed disposal sites, both of which are in ample supply.
Risks of Handling Lead vs. Asbestos
The largest and most significant difference between asbestos and lead abatement work is in the nature and immediacy of the risk. Asbestos abatement often involves commercial or industrial settings where it poses an occupational risk, but not a general health risk. To the extent that abatement involves a residential setting, the work, because of the nature of the building products involved, is usually confined to the utility areas of the dwelling, most often the cellar, or to the exterior and not to living space. This sharply reduces opportunity for exposure to residents. Moreover, the latency of diseases relating to exposure to asbestos is 15 to 30 years, making it difficult to pinpoint the time and place of exposure. As a result, liability accruing to the asbestos contractor for exposure to or illness by one of his clients is very low.
Lead on the other hand, while historically used extensively in paints for all applications, possesses the greatest risk in those areas where the paint can be ingested by children. Almost by definition, this is in the living areas of residential dwellings and in public buildings like schools frequented by children. Even within these areas, concern is generally limited to surfaces where the paint is deteriorated and peeling so that flakes could be ingested or on places where a child might actually chew the paint (mountable surfaces). As a result, abatement most often occurs in those areas where exposure for those most susceptible to lead poisoning is greatest. Of even greater concern and risk, latency is near zero. That is to say that elevated lead levels in blood occur shortly after ingestion (or inhalation in the case of airborne dust). These factors pose much higher levels of potential liability for the lead abatement contractor and will result in increasingly stricter regulations of the abatement process and more rigorous training and licensing for contractors.