Health effects of lead

For an excellent, comprehensive review of the chemistry, environmental, and anthropogenic release, environmental fate, and environmental and human health effects of lead, see Air Quality Criteria for Eead, Vol. I—IV, EPA-600/8-83/028a-dF, U.S. Environmental Protection Agency, Washington, D.C., June 1986, -Msd Air Quality Criteria for Eead Supplement to the 1986 Addendum, EPA-600/8-89/049F, U.S. Environmental Protection Agency, Washington, D.C., Aug. 1990. 

Existing Information on Health Effects of Lead 5-1 Frequency of NPL Sites with Lead Contamination... 

As discussed in the introduction to Section 2.2, the bulk of the human data on the health effects of lead are expressed in terms of internal exposure, or PbB levels, rather than external exposure levels (i.e., mg/m3 or mg/kg/day). For the general population, exposure to lead occurs primarily via the oral route with some contribution from the inhalation route, whereas occupational exposure is primarily by inhalation with some oral. Therefore, it is difficult to distinguish specific routes and levels of exposure. For this reason, the human health effects data for lead will be presented in terms of PbB levels in this section. Health effects associated with human exposures to lead and internal lead doses are shown in Table 2-1. 

Studies in rodents, dogs, and non-human primates have demonstrated all of the major types of health effects of lead that have been observed in humans, including cardiovascular, hematological, neurodevelopmental, and renal effects (EPA 1986a). These studies also provide support for the concept of blood lead concentration as a metric of internal dose for use in dose-response assessments in humans. 

Section 104(i)(5) of CERCLA directs the Administrator of ATSDR (in consultation with the Administrator of EPA and agencies and programs of the Public Health Service) to assess whether adequate information on the health effects of lead is available. Where adequate information is not available, ATSDR, in conjunction with the National Toxicology Program (NTP), is required to assure the... 

Ongoing studies regarding the health effects of lead were reported in the Federal Research in Progress File (FEDRIP 1998) database. Table 2-13 presents a summary of these studies. 

The absorption, distribution, and subsequent health effects of lead illustrate the basic principles of toxicology. Foremost is the sensitivity of children to the adverse... 

Lead is one of the most intensively studied hazardous compounds of the twentieth century. The more toxicologists and other researchers investigated the health effects of lead, the more they realized that even very low levels of lead exposure were hazardous. The most common biomarker of lead exposure is the blood lead level, usually measured in micrograms (jig) per one hundredth of a liter of blood (dl) or jlg/dl. For example, many regulatory agencies set 40 jlg/dl as a level of concern for adult male workers. Typically, at this level workers would be removed from the environment responsible for the exposure and ideally some determination would be made as to the cause of the exposure. The blood level of concern for children has dropped steadily, as shown in Figure 7.1. 

Web site contains presentation material related to the health effects of lead. 

Health Canada provides information on the health effects of lead and remediation programs. 

Lead is highly toxic when absorbed into the body, especially for young children. A level of 10 micrograms of lead per decilitre of blood is cause for concern. Do research, then write a report describing the health effects of lead. Include information on the sources of this heavy metal and on how lead might be absorbed by a child. 

The health effects of lead have become much better understood since the middle of the 20th century. At one time, the metal was regarded as quite... 

Lead Lead is the most ubiquitous of the ne-phrotoxicant metals in the environment. Like mercury, the health effects of lead have been recognized for centuries with the nervous system as well as the kidney being a target for certain forms of these metals. Sources of exposure to lead include food ( 100pg or less per day for adults), lead-based paints, industrial emissions, lead dusts and lead-glazed pottery. 

U.S. EPA, Health Effects of Lead, fact sheet. Available at http //www.epa.gov/dclead/EPA Lead Health Effects FINAL%20 l2.pdf (accessed September 2004). 

The mounting concern in the last years on the negative health effects of lead in the environment has resulted in the reduction of the gasoline lead content and the promotion of the use of lead free gasoline. 

Human health effects of lead. In The Biogeochemistry of Lead in the Environment. J.O. Nriagu (ed). Elsvier, North-Holland. 

Of the range of metals encountered in lead and zinc plants, some are widely recognised to possess potentially harmful effects if absorbed into the body in too large a quantity. Lead and cadmium are probably the best known of these but others can be equally, or indeed more harmful. On the other hand, certain metals are generally regarded as benign zinc and copper are especially so since both arc essential for life. However, even essential elements can have harmful effects when absorbed in excessive quantities. The potential health effects of lead and zinc, and of all the metals most cotrtmonly found in conjunction with them, are outlined below. 

So what is known abont lead It is one of the few elements which seem to have no biological function, and its water soluble compounds are mostly toxic. In the human body, it accnmnlates in the bones as insoluble phosphates. Today s human bones contain about double the amount of lead that was measured in Stone Age skeletons, yet today s values are several times lower than it was in the bones of people who lived in the last two millennia. The health effects of lead remained im-known for a surprisingly long time in hrnnan history. 

A large body of literature on health effects of lead exposure and faetors that influence lead toxicity has been published sinee the 1978 OSHA standard was established. Most recently, the US National Toxicology Program (NTP) released a monograph on the health effects of low-level lead exposure, defined by the NTP as BLLs of under 10 gg/dL and in some eases under 5 gg/dL. The... 

The committee also considered studies that reported an association between cumulative lead dose, as assessed by cumirlative blood lead index (CBLI) or bone lead concentration, and adverse health outcomes. Associations of health outcomes with CBLI or tibia lead concentrations are probably representative of longer-latency, chronic health effects of cumulative dose. In considering CBLI and bone lead data, the committee used the following assumptions a BLL of 40 pg/dL over a 40-y working lifetime would be equivalent to a CBLI of 1,600 pg-years/dL, and this CBLI is roughly equivalent to a bone lead concentration of 40-80 pg/g (on the basis of the pubhshed relation that tibia lead can be estimated as 2.5-5% of the CBLI) (Hu et al. 2007 Healey et al. 2008). Thus, the committee examined evidence that suggested whether a CBLI of imder 1,600 pg-years/dL or a bone lead concentration of imder 40-80 pg/g may be associated with adverse health effects of lead exposure. 

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